1985

REFINEMENT OF TECHNOLOGY FOR EXTRACTION AND UTILIZATION OF APRICOT KERNEL OIL AND

PRESS CAKE

ThesisThesisThesisThesis

by

HIMANSHU SHARMA

Submitted in partial fulfilment of the requirements for the degree of

MASTER OF SCIENCE

FOOD TECHNOLOGY

COLLEGE OF HORTICULTURE

Dr Yashwant Singh Parmar University of Horticulture and Forestry, Nauni,

Solan - 173 230 (H.P.), INDIA 2013

Dr. P.C. Sharma Depar tment of Food science and Technology Sr. Horticultural Technologist Dr. Y. S. Par mar University of Horticulture

and Forestry, Nauni-Solan--173 230 (H.P. )

CERTIFICATE – I This is to certify that the thesis entitled, “Refinement of technology for

extraction and utilization of apricot kernel oil an d press cake” submitted in

partial fulfilment of the requirements for the award of degree of

MASTER OF SCIENCE FOOD TECHNOLOGY to Dr Y S Parmar University of

Horticulture and Forestry, Nauni, Solan (H.P.) is a record of bonafide research work

carried out by Mr. Himanshu Sharma (H-2010-22-M) under my guidance and

supervision. No part of this thesis has been submitted for any other degree or

diploma.

The assistance and help received during the course of investigations has

been fully acknowledged.

______________________ Place: Nauni, Solan Dr. P.C. Sharma Date: (Chair man, Advisory Committee)

CERTIFICATE – II This is to certify that the thesis entitled, “Refinement of technology for

extraction and utilization of apricot kernel oil an d press cake” submitted by Mr.

Himanshu Sharma to Dr. Y S Parmar UHF, Nauni, Solan (H.P.) in partial fulfilment

of the requirements for the award of degree of Master of Science Food

Technology has been approved by the Student’s Advisory Committee after an oral

examination of the same in collaboration with the internal examiner.

_________________________ ___________________ Dr. P.C. Sharma Internal Examiner (Chairman, Advisory Committee) Dr. Girish Shar ma

Members, Advisory Committee

____________________ __________________ Dr. (Mrs.) Devina Vaidya Dr. (Mrs.) Manisha Kaushal ______________________ Dr. (Mrs.) Monika Sharma

_______________________________ Dean’s Nominee

Dr. S. K. Patiyal

________________________ Professor and Head

Department of Food science and Technology

________________________

Dean College of Horticulture

CERTIFICATE – III

This is to certify that all the mistakes and errors pointed out by the

external examiner have been incorporated in the thesis entitled, “Refinement

of technology for extraction and utilization of apr icot kernel oil and

press cake” submitted by Mr. Himanshu Sharma (H-2010-22-M) to Dr.

Yashwant Singh Parmar University of Horticulture and Forestry, Nauni, Solan

(Himachal Pradesh) in partial fulfilment of the requirements for the award of

degree of MASTER OF SCIENCE in Food Technology.

__________________________________________

(Dr. P.C. Sharma) Sr. Horticultural Technologist

Chairman, Advisory Committee

__________________________________________

Dr. V.K. Joshi (Professor & Head)

Department of Food Science Technology Dr. Y. S. Parmar UHF, Nauni, Solan – 173 230 (HP)

ACKNOWLEDGEMENT

Every result arrived at is a modest beginning for a higher goal. My work in the

same spirit is just a step in the ladder. It is a drop of ocean. No work can be turned as

a one man show. It needs the close cooperation of friends, colleagues and the guidance

of experts in the field to achieve something worthwhile and substantial.

Sheer words cannot help articulate my most candid gratitude to the chairperson

of my advisory committee, Dr. P.C. Sharma, whose superb guidance, critical analysis,

constructive criticism, constant enforcement & unparallel execution of the essential

requisites during the entire course are beyond the reach of my formal words. I would

remember him more as a guardian than as a guide.

I emphatically extend my heartfelt thanks to the worthy members of my

advisory committee Dr. (Mrs.) Devina Vaidya, Dr. (Mrs.) Manisha Kaushal and Dr. (Mrs.)

Monika Sharma for their constant help, encouragement and valuable suggestions during

the investigation and manuscript preparations.

I would like to avail this chance to extend my thanks to Dr. V.K. Joshi (Professor

and Head, Department of Food Science and Technology) for their wise guidance and

suggestions.

Nostalgia prevails over me as I recall the amiable, ineffable, unforgettable

company and youthful insouciance of my friends without which life would have been

insipid and devoid of hue.

Special thanks are due to my seniors Reena, Vikas Chopra, Vinay Chandel, Manish

Thakur and Prem Prakash, the faculty, office, field and Laboratory staff are thankfully

acknowledged.

I also extend my sincere thanks to the Keerti kaundal, kajal khattri and Sita

sharma for their help & cooperation.

Above all, the utilitarian asset, of course, my adorable and esteemed Dadiji,

Papa, Mumma, Chachaji, my elder brother and bhabhiji, didi and jiju, deserve my

ravishing thanks, whose benignant advice and abiding hallowing, always stood by me in

tough times.

Last but not the least; I thank almighty God for everything, who continues to

look after despite our flaws and limitations.

Needless to say, errors and omissions are mine.

Date: 06-01-2013 Place: Nauni, Solan (Himanshu Sharma)

CONTENTS

Chapter Title Page (s)

1 INTRODUCTION 1-3

2 REVIEW OF LITERATURE 4-17

3 MATERIALS AND METHODS 18-28

4 EXPERIMENTAL RESULTS 29-45

5 DISCUSSION 46-57

6 SUMMARY AND CONCLUSION 58-61

7 REFERENCES 62-67

• ABSTRACT 68

• APPENDICES I-IV

LIST OF TABLES

Table Title Page No.

1 Soaking treatments of apricot stones and kernels to optimize kernel separation efficiency in mechanical separator

20

2 Detail of pretreatments of apricot kernels prior to extraction of oil

20

3 Detail of pretreatments of press cake followed by extraction of volatile oil

22

4.1 Effect of soaking treatments of decorticated apricot stone fractions on the angle of static friction (θ) of stones, kernels, shells and mixture of shells and kernels on different rolling surfaces

30

4.2 Effect of soaking treatments on the moisture and size parameters of apricot stones and kernels.

31

4.3 Effect of soaking treatments on the efficiency of kernel separation in mechanical separator

33

4.4 Effect of soaking, steaming and oil extraction methods on the yield and quality of apricot oil and press cake

36

4.5 Effect of soaking, steaming and oil extraction methods from apricot kernels on the Tintometer colour units of extracted oil

38

4.6 Effect of soaking, steaming and oil extraction methods from apricot kernels on the quality characteristics of extracted oil

39

4.7 Effect of soaking, steaming and oil extraction methods from apricot kernels on the Fatty acid composition (% w/w) of extracted oil

42

4.8 Standardization of method for extraction of hydro-distillate/volatile oil from apricot kernel press cake

43

4.9 Effect of different concentrations (%) of apricot press cake volatile oil on the mycelial growth rate of some plant pathogenic fungi

44

4.10 Inhibitory effect of apricot press cake volatile oil against some plant pathogenic fungi

45

LIST OF PLATES

Plate Title Between

Pages

1. Mechanical separator for separation of apricot kernels from decorticated stone mass

32-33

2. Apricot kernel oil extracted through Table oil expeller 36-37

3. Volatile oil from apricot kernel press cake 44-45

4. Mycelial growth inhibition caused by volatile oil from apricot kernel press cake after 7 days of incubation in different fungi

44-45

LIST OF FIGURES

Figure Title Between

Pages

1. Effect of soaking pre-treatment on angle of static friction (θ) of apricot stones, kernels, shells and shells+kernels on different surfaces

30-31

2. Effect of soaking pre-treatment on sphericity (%) of apricot kernels

30-31

3. Effect of pre-treatment on separation efficiency of apricot kernels in mechanical separator 34-35

4. Effect of pre-treatment of apricot kernels on yield (%) of extracted oil for table oil expeller 34-35

5. Effect of pre-treatment of apricot kernels on the HCN content (mg/100g) of extracted oil and press cake 40-41

6. Effect of pre-treatment of apricot kernels on the tocopherol content (µg/g) of extracted oil 40-41

7. Benzaldehyde content of volatile oil from apricot kernel press cake 44-45

CHAPTER–1

INTRODUCTION

The apricot (Prunus armeniaca L.) a member of Rosaceae family is one

of the most important temperate fruit grown in India. Among stone fruits, apricot

ranks next only to plum and peach. Apricot has wide climatic adaptability and

grows well between elevations of 900-2000 meter above mean sea level. In India

it is grown in the states of Himachal Pradesh, Jammu & Kashmir and Uttrakhand.

Total production of apricot in the country has reached to be 16,739 tonnes from

an area of 4,886 ha during the year 2011 (FAO, 2011).

In Himachal Pradesh, it occupies an area of 3483 hectare with annual

production of 2,447 m tons (Anonymous, 2012). Beside cultivated apricots, a

substantial quantity of wild apricots commonly known as Chulli, Chullu is also

found growing in various parts of HP, Uttarakhand and J&K.

Both cultivated and wild apricots are used in processing for conversion

into different value added products. During these processing operations, a large

quantity of stones/pits are left after utilization of edible portion are thrown as

waste, the kernel of which can serve as good source of oil. Locally, small

quantity of stones is used for extraction of oil, but the method of oil extraction is

quite unhygienic and result in low oil yield with poor quality. The developed

method of apricot oil extraction consisting of mechanical decortication of stones,

separation of kernels by dipping in salt solution, extraction of oil in table oil

expeller, filtration in oil filter press followed by packaging ( Sharma et al., 2005)

further needs refinement to improve the yield and quality of oil.

After decortication of stones, the kernels are generally separated by

dipping the crushed shell as well as kernels in the salt solution, which helps in

separation of kernels (Sharma et al., 2005). However, the adoption of method is

limited due to apprehension of presence of salt in the kernels and oil. The

development of mechanical separator is required for separation of kernels. The

mechanical separator works on the principle of rolling of spherical kernels on the

moving belt. The roundness of kernel is used to allow them to roll on the belt.

2

Soaking of stones or kernels result in their swelling (Fathollahzadeh et al., 2008).

This property can be utilized for making the kernel spherical to allow them to roll

on the upward moving belt, to help in their separation. However, soaking also

affects the oil yield and quality which needs detailed scientific investigations.

Physical properties of apricot kernel are necessary for the design of

equipments of processing, transportation, sorting, kernel separation and oil

extraction. Fathollahzadeh et al. (2008) described the physical properties of

apricot kernels as a function of moisture content. The physical parameter like

length, breadth, thickness, geometric mean diameter and surface area of stones as

well as kernels are known to affect quality as well as yield of the oil. Thus

optimization of this parameter is also helpful in designing the equipment for

kernel separation.

The extraction of oil from apricot kernels is dependent upon many factors

such as moisture content in the kernels, extent of release of oil from the kernels,

temperature used during oil extraction and pressure used in the expeller for oil

extraction, etc. Most of the factors also affect the quality and quantity of the oil.

Thus, there is a need to optimize the method for extraction of oil from apricot

kernels.

The press cake left after extraction of oil from bitter kernels of almond is

the source of volatile oil commercially known as bitter almond volatile oil. The

volatile oil does not exist as such in the kernels but in the form of cyanogenic

glucoside-amygdalin (C20 H27 NO11- mandelo nitrile genitobioside). In the

presence of inherent β-glucosidase (emulsin) enzyme, the amygdalin is

hydrolyzed in to benzaldehyde, HCN and glucose. Upon completion of the

hydrolysis, the material is steam distilled to collect the volatile portion of the

benzaldehyde. The press cake of bitter almond yields about 1 per cent volatile oil

corresponding to about 0.5 per cent from kernels. The residue, which is free from

HCN, can be used as an animal feed or for isolation of proteins. Generally, two

types of kernels i.e. sweet and bitter are found in both cultivated and wild

apricots. Volatile oil, which is identical with bitter almond oil, can be distilled

from bitter apricot kernel and press cake which is cheaper and give higher yield

(0.8-1.6%) than that of bitter almond kernels. The press cake from bitter apricot

3

kernels is known to yield 1.6 per cent volatile oil. Thus, after extraction of oil

from the kernel, the press cake can be used for extraction of volatile oil after

steam distillation. After removing the HCN from the volatile oil, the

benzaldehyde, which is the chief constituent in the volatile oil, can be used as a

flavourant in food industry as well as in cosmetic industry. Further the

benzaldehyde and HCN are reported to possess good antimicrobial properties

which can be used against many bacterial and fungal diseases. The available

information on development of Mechanical kernel separator, improved oil

extraction method and commercial method for extraction and utilization of

volatile oil from left over press cake is scanty. Thus, the present study has been

undertaken to meet the following broad objectives:

� To optimize method for separation of kernels from decorticated apricot

stones mass.

� To standardize pre-treatment for improving yield and quality of apricot

oil.

� To develop method for extraction and utilization of volatile oil from

apricot kernel press cake.

CHAPTER–2

REVIEW OF LITERATURE

In Himachal Pradesh large area is under wild apricot plantations, whose

fruits are mainly utilized for making country liquor while stones are used for oil

extraction purposes. Owing to its perishable nature, majority of apricot fruits are

utilized as fresh as well as in drying and processing for preparation of different

value added products. After processing, large quantity of stones/pits are left and

are thrown as a waste which can be utilized for oil extraction and preparation of

different value added products. Except for few solitary reports on chemical

characteristics of oil from apricot fruit kernels and utilization of oil for value

addition, no systematic work has been reported in the literature. Besides, very

little work has been conducted on utilization of press cake left after kernel oil

extraction in preparation of value added products. Nevertheless the work

conducted on different aspects of extraction and utilization of kernel oil and press

cake for preparation of different products has been reviewed as under.

According to Dwivedi and Dwivedi (2007) chulli fruits are sour in taste

and cannot be used for table purpose. Also, the kernels, which is obtained from

the wild apricot, is bitter and sour and cannot be consumed as dry fruit. For this

reason, it is used primarily for oil extraction and left over meal is used as animal

feed after it is boiled. The apricot oil has immense medicinal properties and is

used for joint pain etc. Besides, the oil is used for cooking after it has been boiled

properly and also for cosmetic use (Parmar and Sharma, 1992).

2.1 Composition of fruits

Physical character of apricot fruits grown in different area are reported to

vary. According to Sharma (1994) fruit weight of apricot grown in Kinnaur

district of Himachal Pradesh ranged from 4.0 to 29.3 g with fruit weight and

diameter varying between 1.9 to 3.6 cm. Average weight of stones from different

fruits in Kinnaur in Himachal Pradesh varied between 0.5 to 2.9 g while other

parameter were recorded as flesh stone ratio of 2.7 to 15.5 and kernel weight of

0.2 to 0.7 g.

5

Sharma et al. (2005) reported that apricot grown in Solan has stone

weight ranging between 1.106 to 1.150 g with shell thickness of 1.19 to 2.01 mm.

while the pulp/stone ratio of 9.9:1.0 to 13.3:1.0 and kernel weight of 0.35 to 0.42

g. While most of the fruits grown in kumaon region of Uttarakhand were found to

be larger in size with size parameter varying between 3.13 to 5.55 cm in length

and 3.16 to 4.87 cm diameter (Rodriquez et al. 1971). The average share of

kernel in the total weight of the fruit is 26 per cent while that of endocarp is 74

per cent. Based on the chemical composition and percentage of kernel, apricot is

considered as similar to almond.

2.2 Stones/pits

The pits/stones of wild apricot fruits are considered as waste and are

thrown away by the farmers. Mean fruit weight of bitter and sweet kernelled

apricots ranged between 8.0 to 15.1 g and 16.0 to 18.3 g with the stone recovery

of 12.7 to 22.2 per cent and 11.7 to 13.3 per cent respectively (Gupta and

Sharma, 2009).

Sharma et al. (2005) reported that the stone weight in apricot however

ranged between 1.16 g (chulli) to 1.50 g (Newcastle), whereas the thickness of

shell was recorded to be 1.19 mm. Gupta and Sharma (2009) reported stone

weight in wild apricot ranged from 1.78 to 1.92 g while, stone weight of sweet

kernelled stones were ranging from 1.88 to 2.43 g. However, the percentage of

kernel and pits in various stone fruits is also known to vary with the variety, agro-

climatic condition, location etc.

2.3 Kernels

Hallabo et al. (1985) found that the apricot seeds represent about 15 per

cent of the fruit and kernel constitutes about 34 per cent of seed. Similarly,

Iordanidow et al. (1999) found that the pulp, resulting after processing of apricot

mainly comes from the flesh of the fruit and it consists of 55 per cent of the total

fruit. The seeds contain kernels at 13.5 to 38.0 per cent of their weight. Sharma et

al. (2005) recorded length of apricot kernels as 3.58 to 4.52 mm and kernel

thickness as 5.27 to 6.42 per cent.

6

2.4 Physical properties of apricot stones and kernels

According to Fathollahzadeh et al. (2008), the physical properties of

stones are necessary for the design of instrument for processing, transportation,

sorting and separating. The physical properties of apricot kernels have been

evaluated as a function of moisture content varying from 3.19 to 17.46 per cent.

With increase in moisture content, kernel length, width, thickness, geometric

mean diameter and surface area increased. The sphericity varying from 59.79 to

62.21 per cent; while mass (g), thousand grains mass (g), volume (cm3) and true

density (kg/m3) ranged between 0.380 to 0.448 g, 381.6 to 447.9 g, 0.442 to

0.463 cm3 and 882.588 to 983.383 kg m-3 respectively in different samples of

apricot stones. The porosity and bulk density decreased from 52.68 to 51.33 per

cent and 471 to 406.8 kg m-3 respectively as varying moisture contents. The

coefficient of static friction on all surfaces increased as the moisture content

increased and the rupture strength in weakest direction (through length) decreased

from 23.443 to 16.620 N. Thus, moisture exerted a decisive role on the size

parameter of apricot stones and kernels.

Technological properties such as dimensions, geometric mean diameter,

sphericity, surface area, bulk density, true density, porosity, volume, mass, 1000-

unit mass, coefficient of static friction on various surface and rupture force in

three-axis, were determined at 82.34, 16.48 and 13.03 per cent moisture contents

for apricot fruits, apricot pits and apricot kernels, respectively (Fathollahzadeh et

al. 2008). Bulk densities of fruits, pit and kernels were reported to be 443.2,

539.4 and 540.1 kg m-3, the corresponding true densities were 940.7, 1045.5 and

1023.6 kg m-3 and the corresponding porosities were 52.87, 48.40 and 47.21 per

cent, respectively. Further, it was found that values for volume, mass and surface

area of fruits were larger than those of pits and kernels. Static coefficient of

friction of fruit on all surfaces (wood, glass, galvanize sheet and fiber glass sheet)

were measured and static coefficient of friction was less bout for pits and

kernels on glass and their value were 0.474 and 0.188, respectively. Rupture

force of fruit, pit and kernel were 10.11, 497.79 and 18.92 N through length,

7.98, 322.59 and 41.97 N through width and 7.01, 337.21 and 99.58 N through

thickness. Results showed that rupture force through length were minimum and

7

this result is very important factor in designing post harvest machines, especially

for apricot pit crusher machine (Ahmadi et al., 2009).

Polat et al. (2007) studied the effects of heating process and warping

effect on breaking of apricot pits and obtaining of its kernel without damage. For

this aim, heating process (350 oC) was applied to apricot pits. Heated pits were

fallen onto the rotating disc and they were warped to warping wall by centrifuge

effect. Three different disc revolution namely 400, 500 and 600 min-1 and four

different moisture contents of apricot pits namely 6.7, 15.5, 22.2 and 31.5 per

cent were used. The study revealed that increasing the moisture content caused

increase in amount of breaking with sound kernel. Increasing of disc revolution

increased ratio of damaged kernel. The highest breaking amount was determined

with heated pits that had 31.5 per cent moisture content and warped with 400

min-1 disk revolution. Haciseferogullari et al. (2007) studied physical and

chemical characteristics of the six samples of apricot (Prunus armeniaca L.)

fruits. These properties are necessary for the design of equipments for harvesting,

processing, and transportation, separating and packing. Technological properties

such as length and diameter of fruit, mass, volume of fruit, geometric mean

diameter, sphericity, bulk density, fruit density, porosity, projected area, static

and dynamic coefficient of friction were determined at 83.27 per cent (Zerdali),

77.79 per cent (Cataloglu), 82.1 per cent (Hacihaliloglu), 79.79 per cent

(Hasanbey), 82.31 per cent (Soganci) and 77.37 per cent (Kabaasi) moisture

content. The values of length, mass, geometric mean diameter and sphericity of

six different apricot fruits were established between 29.26 mm and 46.98 mm,

14.35 to 41.48 g, 28.99 to 41.15 mm, 0.876 to 0.991 per cent, respectively. Thus,

detailed bioengineering properties of fruit, stones and pits can be utilized for

designing of machine for their decortication.

2.5 Decortication of apricot stones

Decortication is the method of breaking nuts/stones to separate the

kernels. Reddy et al. (1995) developed a hand operated decorticator for apricot

nuts in Oil Technology Research Institute, Anantpur. However, the possibility of

using the decorticator in extraction of kernels from hardy stones of wild apricot is

8

yet to be explored. Similarly, for decortication of apricot stones decorticator has

been designed and developed which has been reported to decorticate 42 kg

pits/hour as against 2.25 kg pits/hour by manual decortication (Sharma et al.,

2005). The clearance between the two rollers for stones of different fruits has

been reported to be 8.25 to 9.11 mm for apricots and 6.58 to 7.28 for plum stones.

Gupta and Sharma (2009) reported that use of mechanical decorticator is most

appropriate for crushing of stones/pits with respect to ease of handling, efficiency

and economy of the operation. According to Dixit et al. (2010) mechanical

decortication and separation could not only save time and money but also reduce

women drudgery (due to manual breaking of stones to separate kernel). The

technology was reported to be suitable for promotion of entrepreneurship on the

processing of apricot oil from apricot kernel in the production catchment.

2.6 Kernel separation

The separation of kernels from the crushed mass is quite laborious and

time consuming operation. The kernel separation method using 20 per cent salt

solution has been optimize by Sharma et al. (2005) with the kernel separation

efficiency of 4.47 kg/hr in apricot, 2.783 kg/hr in peach kernel and 1.633 kg/hr in

plum kernels. Gupta and Sharma (2009) reported that dipping of crushed shells

and kernels in 25 per cent salt solution is optimum for separation of kernels.

However, dipping of kernels in salt solution is also likely to affect the taste and

quality with the apprehension of salt in the oil. Thus, there is need for further

standardization of the method for kernel separation using mechanical separation

beside other considerations.

2.7 Oil extraction

Traditionally, wild apricot oil is extracted manually by crushing the

kernels on pastle and mortar as well as pressing in between the hands. The quality

of this oil is considered better by the local tribal’s with a good pharmaceutical

significance. However, the method of oil extraction is quite cumbersome with

low yield. Thus, the use of oil press (power operated ghani) has been practiced

for oil extraction from stone fruit kernels. The oil yield from wild apricot by

using oil press method was found to be 40.42 per cent in apricot (Aggarwal et al.,

9

1974), against the oil recovery of 50.90 per cent obtained through the solvent

extraction method (Abd El Aal et al., 1986) while, Sharma et al. (2005) recorded

an oil yield of 34.5 per cent by using oil press against the value of 45.03 per cent

in solvent extraction.

Gupta and Sharma (2009) found that the oil yield from bitter kernelled

wild apricot obtained from Mandi, Shimla and Kinnaur areas in Himahcal

Pradesh ranged between 45.6 to 46.3 per cent and sweet kernelled resulted in oil

yield of 46.9 to 47.6 per cent. The use of table oil expeller was optimized for

extraction of oil from separated kernels with an oil yield of 38 to 40 per cent in

wild apricot fruit kernels (Gupta and Sharma, 2009). The available information

indicates that only cold extraction method comprising of passing of apricot

kernels in the oil press or oil expeller without any pre-treatment for extraction of

oil is used. However, pretreatment of raw material like soaking as well as

steaming is known to affect the yield and quality of oil and then calls for detailed

investigation.

2.8 Oil yield

Sherin (1994) recorded a yield of 46.5 per cent oil in apricot cultivar NJA

13 in Pakistan. According to Femenia et al. (1995) sweet apricot kernels

contained more oil (53g/100g kernels) than bitter kernels (43g/100g kernels). The

oil yield in apricot kernels was recorded as 43.03 per cent in chulli and 44.36 per

cent in new castle cultivar (Sharma et al. 2005).

According to Dwivedi and Dwivedi (2007) when the temperature of the

oil extraction apparatus reaches above 100 oC, the dough prepared on the oil

extraction apparatus, is spread at one end of the extraction rock and wetted with

about 50 to 75 ml water. This is the most important step, because the oil can be

extracted only as water suspension. The use of table oil expeller was optimized

for extraction of oil from separated kernels with an oil yield of 38 to 40 per cent

in wild apricot fruit kernels (Gupta and Sharma, 2009).

10

2.9 Physico-chemical characteristics of oil

2.9.1 Colour

The colour of oil besides visual appearance is usually compared in a

Lovibond Tinto meter using a 1 inch or 51/4 inch cell or by measuring the optical

density. Cruess (1958) reported that bitter apricot kernel oil obtained after

refining were light pale yellow in colour. Kamboj (2002) reported that the kernel

oils of apricot, peach and plum were yellow except Santa Rosa which was

reddish yellow in colour. Abd El Aal et al. (1986) showed that apricot kernel oil

was light yellow in colour having 35Y and 5R Tintometer Colour Units (TCU).

Gupta (2006) showed that the kernel oil from bitter apricot was deep yellow

whereas sweet kernel oil was light yellow in colour. The Tintometer colour unit

(TCU) also reflected the yellowness as predominant colour (6.4 to 6.9 TCU) in

bitter kernel oil followed by oil from sweet kernelled apricot with yellow as

predominant colour units (5.7 to 5.8 TCU) and red colour units ranged between

0.1 to 0.3 TCU in bitter kernel oil and 0.1 to 0.2 TCU in sweet kernel oils.

2.9.2 Composition of oil

Iordanidow et al. (1999) reported that apricot kernels contained 27.7 to

51.6 per cent oil 20.3 to 45.3 per cent protein. The kernels also contained sugar

(4.1 to 12.9 %), crude fibers (2.2 to 14.3 %) and minerals. The fatty acid

composition of apricot oil resembled to that of olive oil. The oil is reported to

contain 13.7 per cent saturated, 86 per cent unsaturated fatty acid,

linoleic/linolenic acid fraction (64.6 %) was reported to be comparable with

quality of the oil obtained in soyabean oil (Ciulei et al. 1973). Similarly, Alam

(2001) reported that the saturated and unsaturated fatty acid in apricot oil ranged

from 10.53 to 20.34 per cent and 79.66 to 89.47 per cent, respectively. Oleic acid

was found to be the predominant fatty acid (45.72 to 73.10 %) followed by

linoleic acid (15.21 to 42.57 %).

Similarly, Fatma et al. (2010) reported that the apricot seeds contained

high proportions of oil rich in α-tocopherol and oleic acid, an unsaturated fatty

acid. Genetic variation were also found among the cultivars, however bitterness

or sweetness was not significant. On the basis of two years data, total oil content

11

in different cultivars ranged between 42.77 to 54.92 per cent; oleic acid content

65.81 to 71.40 per cent; linoleic acid content 21.27 to 25.64 per cent; palmitic

acid content 5.29 to 6.66 per cent; stearic acid content 1.10 to 1.48 per cent and

palmitolic acid content 0.58 to 0.88 per cent. Oleic acid was negatively correlated

with linoleic acid, palmitic acid, palmitolic acid and α- tocopherol, which was

also correlated with α-tocopherol.

2.9.3 Lipid profile of extracted oil

The kernel oil from wild apricot have been traditionally used by local

tribal as a oil for cooking, body massaging oil and hair oil as it is known good for

eye sight, relief from joint pains etc. Therefore, to conform utility of the extracted

oil it should be evaluated for their fatty acid profile. According to Sharma et al.

(2003) the fatty acid composition of extracted oil shows significantly higher

proportion of unsaturated fatty acid comprising 91.08 to 91.73 per cent while

saturated fatty acid accounting for only 8.58 to 8.91 per cent of total fatty acid

thus exhibiting unsaturated/saturated ratio of 10.22 to 10.65:1. Therefore, the

kernel oil from apricot possesses special dietary importance.

Savage et al. (2001) reported that vitamin E isomers provide some

protection against oxidation of the lipids. So, a measurement of vitamin E

isomers is important due to their anti-oxidative effect and their positive

nutritional effects in human metabolism.

2.9.4 Acid value

The acid value of an oil or fat is defined as the number of mg of

potassium hydroxide required for neutralizing the free acid in 1 g of the sample

and expressed as the percentage of free acid (Ranganna, 2009). Generally, the

acid value is a measure of the extent to which the glycerides in the oil have been

decomposed by the action of enzyme lipase. The decomposition is accelerated by

heat and light. Rancidity is usually accompanied by free fatty acid formation and

the determination is often used as a general indication of the condition and

edibility of oils (Mayer, 1987).

Eckey (1954) reported an acid value of 0.2 to 4.0 (mg KOH/g) in apricot

kernel oil. The range of acid value in different samples of apricot oil has been

12

reported to be 1.07 mg KOH/g (Dhar & Chauhan, 1963); 0.12 mg KOH/g (Abd

El Aal et al., 1986); 3.6 mg KOH/g in wild apricot oil (Aggarwal et al., 1974). In

refined, bleached and deodorized (RBD) oil, the acid value however has been

found to be less than 4.0 mg KOH/g (Anonymous, 2012a). According to Indian

Food Laws, the acid value of almond oil shall not exceed 4.0 mg KOH/g (FSSA,

2006). Sharma et al (2005) reported an acid value within the range of 2.26 to 4.31

mg KOH/g in apricot kernel oils whereas; Gupta and Sharma (2009) reported that

the acid value ranged within 2.27 to 2.78 mg KOH/g in bitter kernelled apricot oil

and 4.27 to 4.35 mg KOH/g in sweet kernelled oils. Further, Bachheti et al.

(2012) reported acid value of 4.05 mg KOH/g in wild apricot oil from Gharwal

region of Uttarakhand.

2.9.5 Iodine value

The iodine value of an oil or fat is defined as number of grams of iodine

absorbed by 100 grams of sample. The glycerides of the unsaturated fatty acids

present (particularly of oleic acid series) unite with a definite amount of halogen

and the iodine value is therefore a measure of the degree of unsaturation. It is

constant for a particular oil or fat, but the exact figure obtained depends on the

particular technique employed. According to Pearson (1976) the range of iodine

value in different fats vary between 30 to 70 g I2/100 g in animal fats (butter, lard

etc); 80 to 110 g I2/100 g in non drying oils (olive oil, almond oil etc); 80 to 140

g I2/100 g in semi drying oils (cotton seed oil, sesame oil, soya oil) and 125 to

200 g I2/100 g in drying oils (linseed oil, sunflower oil etc.).

The iodine value is often the most useful index for identifying oil or at

least placing it into a particular group. It is reported that the less unsaturated fats

with low iodine values are solid at room temperature, or conversely oils that are

more highly unsaturated are liquids (thus representing a relationship between the

melting points and the iodine values). Besides, the degree of unsaturation (i.e. the

higher the iodine value), the greater is the liability of the oil or fat to go rancid by

oxidation (Thimmiah, 1999). A direct fall in iodine value of oil was also observed

by Handoo et al. (1992). Eckey (1954) reported an iodine value of 97 to 109 g

I2/100 g in apricot kernel oils. Dhar and Chauhan (1963) recorded only 87.2 g

I2/100 g as iodine value in apricot oil.

13

Further, Morpankha and Chawaru cultivars of apricots in Kumaon and

Ladakh region were reported to contain 109.9, 99.58 and 80.82, 123.0 g I2/100 g

iodine values respectively (Dang et al., 1964 and Kapoor et al., 1987). The wild

apricot kernel oil had an iodine value of 104.1 g I2/100 g (Aggarwal et al., 1974).

In refined, bleached and deodorized (RBD) apricot oil, the iodine value ranged

from 104 to 112 g I2/100 g (Anonymous, 2012a) and 98 to 110 g I2/100 g

(Chakaraborty and Talapatra, 1965). Abd El Aal et al. (1986) reported an iodine

value of 103.8 g I2/100 g in apricot kernel oil, while Kamboj (2002) recorded the

iodine value of 95.5 g I2/100 g in wild apricot kernel oil. Similarly, Sharma et al.

(2005) reported iodine value of 100.2 to 112.9 g I2/100 g in kernel oil from

apricots grown in Himachal Pradesh. Gupta and Sharma (2009) recorded 110.4 to

112.7 g I2/100 g iodine value in sweet kernelled apricot oil and 100.2 to 100.4 g

I2/100 g in bitter kernelled apricot oil. Bachheti et al. (2012) reported iodine

value of 102.0 g I2/100 g in oil from wild apricot kernels.

2.9.6 Peroxide value

Peroxides are the main initial product of auto-oxidation and can be

measured by various methods based on their ability to liberate iodine from

potassium iodide or to oxidize ferrous to ferric ions. Peroxide number is a

measure of oxidative rancidity, which is expressed as milli equivalent of peroxide

per kg of lipids. Various successful attempts have been made to correlate

peroxide value with development of rancid flavour. According to Jacob (1958)

high peroxide value is the indicator of spoilage in unsaturated fatty acids and

shall not exceed 125.0 meq/kg. However, the amount of oxygen that must be

absorbed and formed to produce rancidity also vary with composition of oil,

presence of antioxidant and condition of oxidation (Nawar, 1985). Generally, the

more unsaturated a fat is, the faster it will go rancid (Anonymous, 2012a).

In apricot oil, the peroxide value has been found to be 0.12 meq/kg by

Abd El Aal et al, 1986. In different samples of commercial apricot oil the

peroxide value has been reported to be 10.0 meq/kg (Anonymous, 2012a); 5.39 to

6.63 meq/kg (Kamboj, 2002) and 4.38 to 5.39 meq/kg (Sharma et al., 2005).

Further, Gupta and Sharma (2009) reported that peroxide value ranged between

5.12 to 5.27 meq/kg in bitter kernelled oil and 4.32 to 4.40 meq/kg in sweet

14

kernelled oil. Ozcan et al. (2010) recorded peroxide value in between 0.83 to 8.29

meq/kg in oil from different cultivars of apricot.

2.9.7 Saponification value

The saponification value of an oil or fat is defined as the number of mg of

potassium hydroxide required to neutralize the fatty acids resulting from the

complete hydrolysis of l g of the sample. The low molecular weight esters of the

fatty acids require more alkali for saponification, therefore the saponification

value is inversely proportional to the molecular weights of the fatty acids in the

fat/oil (Pearson, 1976). As many oils have somewhat similar values (e.g. those in

the olive oil series fall within the range 188 to 196 mg KOH/g), thus, the

saponification value is not, as useful for identification purposes as the iodine

value .The saponification value is of most use for detecting the presence of

coconut oil (255 mg KOH/g), palm kernel oil (247 mg KOH/g) and butter fat

(225 mg KOH/g) which contain a high proportion of the lower fatty acids.

Paraffin with a negligible saponification value, can also be detected and

estimated if present as an adulterant.

According to Eckey (1954) the saponification value in apricot oil ranged

between 188 to 200 mg KOH/g, while, Abd El Aal et al. (1986) recorded a value

of 189.7 mg KOH/g in apricot oil. Similarly, Morpankha and Chawaru cultivars

in Kumaon region were found to contain 191.3 and 193.8 mg KOH/g

saponifiation value (Dang et al., 1964). While, wild apricot oil showed the

presence of slightly lower (188.8 mg KOH/g) level of saponification value

(Aggarwal et al., 1974). Kamboj (2002) reported saponification value of 194.9

mg KOH/g in apricot kernel oil whereas Sharma et al. (2005) recorded a range of

190.2 to 194.4 mg KOH/g in apricot kernel oils. In refined, bleached and

deodorized (RBD) apricot oil, the saponification value ranged from 185 to 195

mg KOH/g (Anonymous, 2012a). According to Gupta and Sharma (2009) the

saponification values of sweet and bitter apricot kernel oils ranged from 193.4 to

193.6 mg KOH/g and 189.8 to 191.3 mg KOH/g respectively. Bachheti et al.

(2012) reported saponification value 190.0 mg KOH/g in wild apricot oil from

Gharwal region of Uttarakhand.

15

2.9.8 Hydrocyanic acid (HCN)

The kernels of stone fruits are reported to contain a cyanogenic glucoside which

upon hydrolysis yield HCN. The lethal dose of HCN for human being is estimated to be

0.5 to 3.5 mg/kg of body weight. In different fruit kernels varying levels of amygdalin and

HCN has been recorded. According to Winton and Winton (1959), an HCN content of

0.06 per cent was recorded in plum kernels where as apricot kernels also contain 0.06 per

cent. Stosic et al. (1987) conducted toxicological test on mice and found that apricot

contain 8.1 mg/kg of HCN as toxic compound. Amygdalin, a cyanogenic glucoside ranges

from 2.5 to 3.5 per cent (dry wt.) of bitter almond seeds. Amygdalin has also been detected

at low levels in some sweet almond cultivars (Mc Carty et al., 1952). Amygdalin is an

association of genitiobiose and mandelic acid (β-gentiobiose of the nitrate of α-

hydroxyphenyl acetic madelo nitrate acid). On the hydrolysis, it is split by the inherent

enzyme β-glucosidase (emulsin) into two molecules of glucose, benzaldehyde and HCN

(Brower, 1969). However, Amar cultivar of apricot did not show the presence of any HCN

in its kernel (Abd EI Aal et al., 1986). Sharma et al. (2005) recorded as 6.47 mg/kg HCN

in apricot oil. Femenia (1995) observed that amygdalin content was very high (5.59

mg/100mg) in bitter apricot kernels. According to Gupta and Sharma (2009) dipping of

kernels in 25 per cent salt solution prior to oil extraction brought about complete removal

of bittering component, HCN in oil. Further, blanching of kernels in boiling water for 40 to

50 min helps in complete detoxification of apricot kernels from the HCN content. Among

different methods of detoxification the use of 10 per cent sodium thiosulphate was found to

be most effective for complete detoxification.

Therefore, it is essential to detoxify this toxic compound before utilization of

kernel oils and press cake as edible and pharmaceutical purposes.

2.10 Utilization of kernel press cake

The press cake left after oil extraction contains amygdalin which yields

about 0.06 per cent HCN (hydrocyanic acid), upon hydrolysis. It is known to be

utilized as fuel and fertilizer as it is considered unfit for cattle feed due to

presence of HCN. Chemically it contains nitrogen (6.64 per cent), phosphoric

acid (2.2 per cent) and potash (1.64 per cent). The seed cake of bitter apricot is

reported to yield about 1.6 per cent of volatile oil. Iordanidow et al. (1999)

reported that the kernel meal can be used for protein isolation by protein

16

extraction, iso-electric precipitation and freeze drying. The protein products at a

75 per cent yield had low protein content (up to 53.5 %), were light coloured and

had comparable functional properties to commercial soya isolate.

2.11 Volatile Oil

Volatile oils are extracted from stone fruit kernels and left over press cake after oil

extraction. The benzaldehyde is the chief constituent of these oils and extraction is done by

steam or water distillation. Gildemeister and Holfmann (1974) reported that bitter almonds

yield from 0.5 to 0.7 per cent, apricot kernels from 0.6 to 1.8 per cent of volatile oil.

According, to Tilakratne (2007) diluting press cake with water (1:10) followed by

immediate distillation yielded about 30 ml. of volatile oil, which contained about 40 per

cent of benzaldehyde, but the essential oil also contained appreciable amount of HCN

(152 mg/100g). In order to remove HCN from the distillate, the volatile oil obtained after

distillation of slurry (press cake + water in the ratio of 1:10) without maceration was re-

distillate with 3 per cent each of CaO and FeSO4, which resulted in 3.3 per cent of volatile

oil with 75 per cent benzaldehyde without HCN.

2.12 Anti-fungal activity of volatile oil

According to Tilakartne (2007) the anti microbial activity of apricot

kernel oil and volatile oil was evaluated against both Escherichia coli and

Staphyloccocus aureus. It was found that volatile oil extracted from press cake

exhibited good anti-microbial activity against both the micro organisms i.e.

Staphyloccocus aureus and Escherichia coli. The inhibition zone developed by

the volatile oil against Staphyloccocus aureus and Escherichia coli measured to be

3.4 cm and 1.2 cm diameter respectively. Apricot oil, however did not exhibit any

anti-microbial activity against Staphyloccocus aureus. While apricot oil showed

good anti-microbial activity against Escherichia coli with the development of

inhibition zone of 2.0 and 1.4 cm diameter respectively. In contrast to these

observations Hammer et al. 1999, recorded no inhibitory effect on Escherichia

coli and Staphyloccocus aureus which might be due to low concentration in the

study. Yigit et al. (2009) also tested the apricot kernel extract against human

pathogenic micro-organism using a disc-diffusion method and evaluated the

minimal inhibitory concentration (MIC) values. The most effective antibacterial

17

activity was observed in the methanol and water extracts of bitter kernels and in

the methanol extract of sweet kernels against the gram-positive bacteria

(Staphylococcus aureus). Additionally, the methanol extracts of the bitter kernels

were very potent against the gram-negative bacteria with a MIC value of 0.312

mg/ml for Escherichia coli. Similarly, significant anti-candida activity was also

observed with the methanol extract of bitter apricot kernels against Candida

albicans consisting of a 14 mm in diameter of inhibition zone and a 0.625 mg/ml

MIC value. Thus, volatile oil from apricot kernels need to be evaluated for

antimicrobial activity against different micro-organisms.

CHAPTER–3

MATERIALS AND METHODS

The present investigation entitled, "Refinement of technology for

extraction and utilization of apricot kernel oil and press cake" was conducted in

the Department of Food Science and Technology, Dr. Y.S. Parmar University of

Horticulture and Forestry, Nauni-173230, Solan (H.P.) during the years 2010-

2013. The experimental details and technique used in these studies are described

under following heads:

3.1 Raw material

Wild apricot stones in bulk left after utilization of edible portion were

processed from Karsog area in Mandi district of Himachal Pradesh (1850 meter

above mean sea level) and brought to the department of Food Science and

Technology, UHF Nauni for experimentation. The stones were utilized for

conducting following three studies

1. Development of method for mechanical separation of apricot kernels after

decortication.

2. Optimization of parameter for oil extraction.

3. Extraction and utilization of volatile oil from apricot kernel press cake.

3.2 Development of method for mechanical separation of apricot kernels after decortication

The suitability of mechanical separator was evaluated for simultaneous

separation of kernels from the crushed apricot stone mass. The mechanical

separator consisted of inclined belt moving in upward opposite direction to allow

rolling of kernels and carrying forward the shells. The inclination angle of the

belt was optimized on the basis of angle of static friction of apricot stones and

kernels on different surfaces. Four surfaces (wood, glass, paper and rubber) were

evaluated to optimize the surface on belt for development of inclined plane type

mechanical separator for apricot kernels. Angle of static friction of apricot stones,

19

kernels and shells on four surfaces was determined with the help of inclined plane

instrument with adjustable slope. In order to make moving inclined plane, the

rubberized belt was optimized on a moving surface for separation of apricot

kernels. The suitability of rubber for its use as a belt was used in the mechanical

separator placed in inclination position about 22.5o from base and move in

opposite direction from the flow of decorticated stones (shells and kernels) which

are dropped from the height to allow the kernels to roll on the belt while shells

being coarse are carried by the moving belt to other end of the separator. The

length of the belt was kept 6 feet with speed of 5 rpm which was found optimum

to achieve separation. The belt was moving with the help of 2 hp motor. The

assembly was provided with forced air fan facility to allow separation of dust and

fine shells/kernels particles while moving on the belt. The efficiency of kernel

separation was compared with the kernel separated by using gravity separation

method (Gupta and Sharma, 2009) which served as the control.

3.2.1 Effect of soaking treatments on the efficiency of kernel separation in mechanical separator

Effect of soaking of apricot stones/kernels in water on the efficiency of

kernel separation in mechanical separator was optimized. Four treatments viz.

mechanical decortication without soaking followed by separation in salt solution

(control) (S1), soaking of apricot stones in water for overnight followed by

decortication and kernel separation in mechanical separator (S2), soaking of

decorticated apricot stones mass in water for overnight followed by kernel

separation in mechanical separator (S3) and mechanical decortication of pre-

soaked apricot stones followed by further soaking of decorticated stone mass

prior to separation in mechanical separator (S4) were studied to standardize

optimum soaking treatment (Table 1). The effect of soaking on change in

physical parameter of apricot stones as well as kernels was studied. The treatment

giving optimum rolling of the kernels on the moving belt was rated as most

appropriate.

20

Table 1: Soaking treatments of apricot stones and kernels to optimize kernel separation efficiency in mechanical separator

Treatment No.

Particulars

S1 Mechanical decortication without soaking followed by separation in salt solution (control).

S2 Soaking of apricot stones in water for overnight followed by mechanical decortication and kernel separation in mechanical separator.

S3 Soaking of mechanically decorticated apricot stones mass in water for overnight followed by kernel separation in mechanical separator.

S4 Mechanical decortication of pre-soaked apricot stones for overnight followed by further soaking of decorticated stone mass for another 12 hours prior to separation in mechanical separator.

3.3 Optimization of parameters of apricot kernel for improving yield and quality of oil

Apricot kernels after separation in mechanical separator were used for

extraction of oil through Table oil expeller. Suitability of soaking apricot kernel

in different proportion of water with or without steaming prior to oil extraction

was standardized as per treatments shown in Table 2. The yield and quality of oil

extracted through Table oil expeller after different pretreatments was compared

with the oil extracted through Soxtec oil extraction apparatus. Treatment showing

maximum oil yield was optimized for the extraction of oil.

Table 2: Detail of pretreatments of apricot kernels prior to extraction of oil

Treatment No.

Particulars

O1 Oil extraction in Soxtec oil extractor from apricot kernels without adding water.

O2 Oil extraction in Table oil expeller from apricot kernels without adding water (Control).

O3 Oil extraction in Table oil expeller after soaking by addition of 5% (w/w) water in apricot kernels.

O4 Oil extraction in Table oil expeller after soaking by addition of 10% (w/w) water in apricot kernels.

O5 Oil extraction in Table oil expeller after steaming of apricot kernels (5 psi) for 15 min without prior soaking in water.

O6 Oil extraction in Table oil expeller after soaking by addition of 5% water in apricot kernels followed by steaming (5 psi) for 15 min.

O7 Oil extraction in Table oil expeller after soaking by addition of 10% water in apricot kernels followed by steaming (5 psi) for 15 min.

21

3.3.1 Solvent extraction

The apricot kernels were ground to a coarse powder in a household mixer

cum grinder prior to its use for oil extraction purposes. 20 g of powdered sample

was weighed in respective thimbles and placed in Soxtec Oil Extraction

Apparatus (M/S Velps Scientifica, SRL, Italy) preprogrammed (Temperature 130

°C, immersion time 360 minutes; washing time 30 minutes; recovery time 20

minutes) for oil extraction using petroleum ether (40-60 oC Boiling Point) as a

solvent. After six hours of extraction process, the crude oil was collected after

recovering about 90% of the solvent and allowing the rest to evaporate in the

oven (Ranganna, 2009). The extracted oil was then packed in pre-sterilized glass

bottles for its later use in analytical purposes.

3.3.2 Table oil expeller (Y2K)

Table oil expeller (Y2K) is a 24 patti screw type oil expeller (M/S Sardar

Engineering Company, Kanpur, India) driven by 5HP motor. In the experiment

the kernels were fed from the hopper at a predetermined flow rate, which were

pressed in between the screw roller (worm) and sidewalls of the expeller. The

kernels were passed 3-4 times until a very thin slip of press cake was obtained.

The extracted oil was filtered through a filter press, which consisted of different

layers of thick nylon cloth through which oil was pumped from the motor for

filteration. The clear oil was then packed in amber coloured plastic bottles (200

ml capacity) and kept in cool dry place until used for further experimentation.

3.4 Extraction and utilization of volatile oil from apr icot kernel press cake

Hydro-distillation apparatus consisted of stainless steel heating unit

capacity 10 litres. The heating pan was provided with a false bottom for placing

solid residue to avoid burning during heating. The vapours were carried through a

vertical tube which was cooled in a horizontally placed stainless steel condenser

and collected in vapour collection tube. The volatile oil containing hydro-

distillate floating in the glass tube was collected periodically. After collection of

about 1 % of the distillate, the diluted cake was removed and another batch was

fed. The press cake left after oil extraction was utilized for extraction of volatile

22

oil in hydro-distillaion apparatus and clevenger’s apparatus. The method was

optimized for separation of benzaldehyde from the mixture of volatile oil

containing HCN. Four treatments T1 (Diluting press cake with water (1:10)

followed by distillation to collect 1 % distillate), T2 (Diluting press cake with

water (1:10) maceration at 50°C for 12 hours followed by distillation to collect 1

% distillate), T3 (Re-distillation of distillate (100 ml) from T1 with 3% each of

CaO and FeSO4 to collect 50 % of volatile oil), T4 (Re-distillation of distillate

(100 ml) from T2 with 3% each of CaO and FeSO4 to collect 50 % of volatile oil)

were used for extraction of volatile oil from the kernel press cake Table 3. Best

treatment with maximum yield of benzaldehyde was optimized for the extraction

of volatile oil from apricot kernel press cake.

Table 3: Detail of pretreatments of press cake followed by extraction of volatile oil

Treatment No.

Particulars

T1 Diluting press cake with water (1:10) followed by distillation to collect 1 % distillate (100 ml)

T2 Diluting press cake with water (1:10) maceration at 50°C for 12 hours followed by distillation to collect 1 % distillate (100 ml)

T3 Re-distillation of distillate (100 ml) from T1 with 3% each of CaO and FeSO4 to collect 50 % of volatile oil

T4 Re-distillation of distillate (100 ml) from T2 with 3% each of CaO and FeSO4 to collect 50 % of volatile oil

3.5 Analysis of stones and kernels

3.5.1 Size of stones and kernels

Size parameters comprising of length, breadth and thickness of stones and

kernels were recorded with the help of Digital Vernier Caliper and

expressed in mm.

3.5.2 Geometric Mean Diameter, Sphericity and Coefficient of Static Friction

Ten apricot stones randomly selected and their kernel were analyzed for

their size parameters like length (l), breadth (b), thickness (t), geometrical mean

diameter (Dg) in mm and sphericity (O). Geometrical dimensions were measured

by using Vernier Calliper with accuracy of 0.01mm. On the basis of three

23

dimensions [length (l), breadth (b) and thickness (t)], geometrical mean diameter

and sphericity of the apricot stones/kernels was calculated by using following

equations (Mohsenin, 1970; Jain and Bal, 1997).

Dg= (l.b.t) 1/3 (1) Dg: Geometric mean diameter

O = [(l.b.t)1/3/l]x100 (2) O: Sphericity

The angle of static friction of apricot stones, kernels and shells on four

surfaces including wood, glass, paper and rubber was determined using inclined

plane instrument. For determining Angle of static friction (θ), the sample (stones,

kernels, shells) was placed on the respective surface with adjustable slope

(Inclined plane instrument). The angle, at which the kernels started to slip, was

indicated as angle of static friction (θ).

3.6 Physico-chemical characteristics of extracted oil

3.6.1 Colour

Instrumental colour of oil was measured in a Lovibond Colour Tintometer

Model E, AF-900 (Tintometer Ltd., Salisbury, U.K.) using one inch cell. The

Lovibond Tinotometer is a subtractive colourimeter based on direct observation

of illuminated sample through a viewing tube. The instrument is provided with

sets of red, yellow and blue glass slides to be used as permanent standards

(Ranganna, 2009). The results were then expressed as red, yellow and blue colour

units (TCU) and discussed on the basis of dullness. The value of colour, which is

lowest, expressed the amount of dullness. The lowest value was then combined

with equal values of other two colours to form a like value of neutral tint or

dullness. The remaining two colours were combined in equal values of the lower.

Thus, red and yellow formed equal units of orange, yellow and blue formed green

and red and blue resulted in violet. The balance of units of the remaining colour

staying unchanged was referred to as predominant colour.

3.6.2 Acid value

Acid value of apricot kernel oil was estimated by titrating a known weight

of sample (10g) containing 50 ml neutral solvent (25 ml ether + 25 ml 95 %

alcohol + 1% phenolphthalein) against 0.1N KOH solution using phenolphthalein

24

as an indicator (FSSAI, 2012). The acid value was calculated by using following

expression:

Titre x Normality of KOH x 56.1 Acid value (mg KOH/g oil) = -------------------------------------------------

Weight of sample (g)

3.6.3 Iodine value

Iodine value was estimated according to Wijs (carbon tetrachloride-acetic

acid solvent) method (FSSAI, 2012). The oil sample (0.26-0.32 g) was mixed

with carbon tetrachloride (25 ml) followed by addition of Wijs solution and then

stored in dark for one hour. After addition of 15 ml of 15 per cent Kl and 100 ml

distilled water, the solution was titrated against 0.1 N sodium thiosulphate using

starch solution as an indicator. The iodine value was then calculated by

subtracting the sample titre from the blank titre using following expression:

(Blank titre - Sample titre) x Normality of Na2S2O3 x 12.69 Iodine value = ------------------------------------------------------------ (g l2 /100 g oil) Weight of sample (g)

3.6.4 Peroxide value

Peroxide value was estimated by taking the sample (5g) mixed with 30ml

Acetic acid- chloroform solution containing saturated KI solution and titrated

against 0.1 N sodium thiosulphate using starch as an indicator and calculated as

milli-equivalent peroxide per kg sample (FSSAI, 2012). The peroxide value was

calculated by using following expression:

(Sample titre- Blank titre) x Normality of Na2S2O3 Peroxide Value = ----------------------------------------------------------- x 1000 (meq/kg oil) Weight of oil (g)

3.6.5 Saponification Value

Saponification value of apricot kernel oils was estimated according to

standard method (FSSAI, 2012). The known weight of sample (1 g) was mixed

with alcoholic potassium hydroxide (25 ml) and the mixture was refluxed for 30

minutes to completely saponify the sample and then titrated against 0.5 N HCI

using phenolphthalein as an indicator. Blank titration was carried out along with

25

the sample. Saponification value of the oil was then calculated by using the

expression as under:

(Blank titre- Sample titre) x 28.05 Saponification value = -------------------------------------------- (mg KOH /g oil) Weight of oil (g)

3.6.6 Hydro-Cyanic Acid (HCN)

3.6.6.1 Qualitative method

To pre-weighed sample (10 g apricot kernels or 10 ml apricot kernel oil),

2 ml freshly prepared 3 per cent FeS04.7H20 solution was added followed by

addition of single drop of 1 per cent FeCI3.6H20 solution. After proper mixing, 10

per cent NaOH solution was added drop wise until no further precipitate formed

followed by dissolving of precipitates by adding diluted H2SO4 (1+9) solution.

The development of Prussian blue colouration indicated the presence of HCN

(AOAC, 1995).

3.6.6.2 Quantitative method (Alkaline-titration method)

Alkaline-titration method was followed for quantitative estimation of

hydro-cyanic acid in apricot kernels and oil. 20 g sample was mixed with 200 ml

water and allowed to stand for 2 hours for complete hydrolysis of amygdalin to

HCN. The mixture was then steam distilled to collect 150-160 ml of distillate in

NaOH solution (0.5g in 20 ml H20) followed by its dilution to 250 ml. 100 ml

aliquot containing 8 ml 6N NH4OH and 2 ml 5 per cent Kl (Pottasium Iodide)

solution was then titrated against 0.02 N AgNO3 to a faint permanent turbid

colour (AOAC, 1995). The HCN content (mg/100g) in the sample was then

calculated using following expression:

Titre x 1.08 x Volume made up x Aliquot taken HCN (mg/100g) = ----------------------------------------------------------- x 100 Sample taken x Distillate taken 3.6.7 Lipid profiling/fatty acid composition

The fatty acid estimation of the apricot kernel oil was determined

according to the method of Metcalfe et al. (1966) by converting them in to

respective fatty acid methyl esters and by using gas liquid chromatography

26

(GLC). Methyl esters of the fatty acids were dissolved in hexane and analyzed by

Gas Chromatograph (GC) on a 2 meter column packed with either 3% SE/30 or

10% DEGS on 80-100 mesh Gas-Chrom Q. Retention times and peak areas were

determined by comparison with respective standards. Methyl esters of the fatty

acids (FA) were formed with BF3-methanol. A known amount of internal

standard (C15:0) was added prior to derivatization of standards and samples. Peak

areas were measured with a Shimadzu CR1A® recording integrator. Recovery

values and constants were determined and used as correction factors.

3.6.8 Vitamin E (Tocopherols)

Sample for estimating of vitamin E (tocopherols) was prepared by

refluxing 1 g of oil containing 10 ml absolute alcohol and 20 ml 1M acidic alcohol in 100 ml flask fitted with reflux condenser for 45 min. Upon cooling, the

sample was transferred to separating funnel along with 2x50 ml water to extract the unsaponifiable matter with 5x30 ml di-ethyl ether, followed by evaporation of combined extract at low temperature under the stream of nitrogen. The residue

obtained was dissolved immediately in 10 ml absolute alcohol.

To aliquot of the sample and standard (0.3-3.0 mg vitamin E) in 20 ml

volumetric flasks, 5 ml absolute alcohol and 1 ml concentration nitric acid was

added drop wise with constant swirling followed by heating at 90 °C for 3

minutes. Upon rapid cooling, the volume was adjusted to 20 ml with absolute

alcohol. The absorbance of samples and standard was measured at 470 nm

against a blank containing 5 ml absolute alcohol and 1 ml conc. nitric acid treated

in a similar manner (Pearson, 1976). The vitamin E in the sample was calculated

from the standard curve and expressed as µg/g.

3.6.9 Benzaldehyde content in volatile oil

A known volume of sample was pipetted out into distillation flask. After

addition of water, 100 ml distillate was collected. Aliquot of distillate was then

diluted with 10 per cent ethyl alcohol to produce absorbance (A) of sample at 249

nm, using 10 per cent of ethyl alcohol blank. Absorbance of standard

benzaldehyde solution was determined at 249 nm against blank (A') of 10 per

cent ethyl alcohol and standard curve was plotted (AOAC, 1995). Benzaldehyde

27

concentration from absorbance (A) was determined at 249 nm and standard curve

and average of 1 ppm benzaldehyde (A) was calculated from following

expression:

Concentration of benzaldehyde in ppm = (A/ A') x F

Where, F is dilution factor.

3.6.10 Antifungal activity of volatile oil

Apricot volatile oil extracted from press cake was evaluated for its

antifungal property against different fungi namely Fusarium sp., Sclerotium sp.

and Macrophomina sp. obtained from Department of Plant Pathology, Dr.

Yashwant Singh Parmar University Nauni. The active cultures of fungi were

maintained and multiplied on potato dextrose agar medium. The apricot volatile

oil was tested in vitro by using the Poisoned Food Technique in Completely

Randomized Design (CRD) to study the inhibitory effect of these oils on mycelial

growth of different fungi. These oils were evaluated at different concentrations

i.e. 5 per cent, 10 per cent, 15 per cent and 20 per cent against the pathogenic

fungi.

Double strength potato dextrose agar medium was prepared in distilled

water and sterilized in autoclave at 1.05 kg/cm3 pressure and 121oC for 20

minutes. Simultaneously, double concentrations of volatile oil were also prepared

in sterilized distilled water. Oil suspensions were added separately to equal

quantities of double strength potato dextrose agar medium aseptically before

pouring into petri plates. After the solidification of medium, these plates were

then inoculated with 2 mm diameter mycelial bit of different pathogenic fungi

taken from actively growing 5 days old culture. A control treatment was also

maintained in which only plain sterilized distilled water was added to double

strength medium. Each treatment was replicated thrice. The inoculated plates

were incubated at 28±1oC. The observation was recorded in the form of radial

growth of pathogenic fungi in millimeter (mm) daily until the control plates were

fully covered with the mycelium. Per cent inhibition was calculated as described

by Vincent (1947):

I = C-T x 100 T

28

Where, I = Per cent inhibition.

C = Growth of fungus in control (mm).

T = Growth of fungus in treatment (mm).

3.7 STATISTICAL ANALYSIS

The data on physico-chemical characteristics of apricot stones, kernels, oil

and volatile oil were analyzed statistically by using Factorial Completely

Randomized Design (CRD Factorial) (Cochran and Cox, 1967) and Logarithmic

Transformation (Gomez and Gomez, 1984). Triplicate determinations were made

for each parameter.

CHAPTER–4

EXPERIMENTAL RESULTS

The present investigation entitled “ Refinement of technology for

extraction and utilization of apricot kernel oil and press cake” was conducted in

the Department of Food Science and Technology, Dr Y S Parmar University of

Horticulture and Forestry, Nauni, Solan (H.P.) during the year 2010-2013. The

results of the study presented in tables 4.1-4.10 are described as under:

4.1 Development of method for mechanical separation of apricot kernels after decortication for development of mechanical separator

4.1.1 Optimization of coefficient of static friction

The angle of static friction of apricot stones and kernels on different

surfaces was found to vary between 20.0 to 22.8o on wood, 9.6 to 14.0o on glass,

13.8 to 16.8o on paper and 22.2 to 25.3o on rubber surface. The highest angle was

found on rubber (25.3o). Soaking of apricot stones brought about significant

improvement on the angle of static friction of stones and kernels. The mean value

of angle of static friction of soaked kernels was recorded as 21.0o on wood, 10.2o

on glass, 14.5o on paper and 22.5o on rubber against 19.0o on wood, 9.0o on glass,

13.0o on paper and 22.0o on rubber in un-soaked material (Table 4.1). Thus, on

the basis of angle of static friction of soaked apricot kernels on rubber, the

inclination angle of rubberized belt in mechanical separator was optimized as

22.5o from the base.

4.1.2 Effect of soaking treatments on moisture and size parameter of apricot stones and kernels

Data presented in Table 4.2 represent the effect of soaking treatments on

the moisture content and size parameters of apricot stones and kernels. As

expected, soaking of apricot stones prior to decortication (D2), soaking of

decorticated stone mass (D3) as well as soaking of stones before and after

decortication (D4) brought about significant increase in moisture content of

stones as well as kernels.

30

Table 4.1: Effect of soaking treatments of decorticated apricot stone fractions on the angle of static friction (θ) of stones, kernels, shells and mixture of shells and kernels on different rolling surfaces

Stone Fraction

Angle of static friction (θ)

Stones/Pits Kernels Shells Shells+Kernels

Unsoaked Soaked Mean Unsoaked Soaked Mean Unsoaked Soaked Mean Unsoaked Soaked Mean

Wood 21.0 22.0 21.5 19.0 21.0 20.0 22.0 22.5 22.3 22.0 23.5 22.8

Glass 11.5 12.5 12.0 9.0 10.2 9.6 12.5 13.0 12.8 12.0 13.0 12.5

Paper 14.0 16.0 15.0 13.0 14.5 13.8 15.5 17.0 16.3 16.0 17.5 16.8

Rubber 23.0 24.0 23.5 22.0 22.5 22.3 24.0 25.5 24.8 24.5 26.0 25.3

CD(0.05) 0.98 1.01 0.78 0.83 1.09 0.68 0.96 0.68 0.69 1.15 0.76 0.66

Fig: 1. Effect of soaking prekernels, shells and shells+kernels on different

Fig: 2. Effect of soaking pre-

0

5

10

15

20

25

30

Un

soa

ke

d

So

ak

ed

Me

an

Un

soa

ke

d

Stones

70.5

71

71.5

72

72.5

73

73.5

74

74.5

75

D1

Sphericity (%)

Effect of soaking pre-treatment on angle of static friction (θ) of apricotkernels, shells and shells+kernels on different surfaces

-treatment on sphericity (%) of apricot kernels

So

ak

ed

Me

an

Un

soa

ke

d

So

ak

ed

Me

an

Un

soa

ke

d

So

ak

ed

Me

an

Kernels Shells Shells+Kernels

Angle of static friction (θ)

D2 D3 D4

Treatment

SPHERICITY (%)

[(l.b.t)1/3/l]x100

apricot stones,

kernels

Wood

Glass

Paper

Rubber

SPHERICITY (%)

[(l.b.t)1/3/l]x100

31

Table 4.2: Effect of soaking treatments on the moisture and size parameters of apricot stones and kernels.

NOTE: - * 20 kg of stones were used for each batch of experimentation Figure in parentheses indicate per cent weight gain after soaking treatment

Treatment*

Particulars Weight after

soaking (kg)

MOISTURE (%)

LENGTH (mm)

BREADTH (mm)

THICKNESS (mm)

GEOMETRIC MEAN

DIAMETER (mm) (l.b.t)1/3

SPHERICITY (%) [(l.b.t)1/3/l]x100

Stone Kernel Stone Kernel Stone Kernel Stone Kernel Stone Kernel Stone Kernel

D1 Mechanical decortication of apricot stones without soaking (control)

- 7.8 4.4 20.0 12.0 15.9 9.0 10.3 6.0 14.8 8.6 74.3 72.1

D2 Soaking of apricot stones in water for overnight followed by mechanical decortication

22.1

(10.5)

15.7 17.0 20.5

12.1

16.4

9.1

10.6

6.1

15.3 8.7 74.5 72.4

D3 Soaking of mechanically decorticated apricot stones mass in water for overnight

23.0

(15.2)

18.4 28.5 -

12.2

-

9.3

-

6.2

- 8.9 - 72.9

D4 Mechanical decortication of pre-soaked apricot stones followed by further soaking of decorticated stone mass for overnight

23.4

(17.0)

20.6 30.4 - 12.6 - 9.4 - 7.0 - 9.4 - 74.6

CD(0.05) - 0.21 0.63 - 0.07 - 0.07 - 0.07 - 0.08 - 0.014

32

Maximum moisture content in stones (20.6 %) and kernels (30.4 %) was

found in treatment S4 as compared to the initial moisture content of apricot stones

(7.8 %) and kernels (4.4 %) without soaking of apricot stones (control).

Consequently, the weight of stones and decorticated mass also exhibited increase

from original weight of 20 kg.

Soaking treatments also brought about significant improvement in

geometrical dimensions of apricot kernels, such as length (12.0 to 12.6 mm),

breadth (9.0 to 9.4 mm) and thickness (6.0 to 7.0 mm). Further with the increase

in the moisture content, the geometric mean diameter of kernels also increased

from 8.6 to 9.4 mm. Sphericity, which is a measure to define the shape of kernels

also exhibited increase from 72.1 to 74.6 per cent (Table 4.2). The increase in the

size parameter like geometric mean diameter and sphericity are expected to make

the kernels more rolling on the belt, which will improve their separation from the

shells.

4.1.3 Optimization of treatments for designing mechanical separator for apricot kernels

On the basis of optimized rubber surface and angle of inclination of belt,

the design parameters of mechanical separator for apricot kernels were worked

out. Out of different surfaces, the use of rubberized belt, it’s placement in

inclination position of 22.5o angle from the base and allowing it to move in

opposite direction was optimized. This arrangement allowed rolling of kernels on

the belt and carrying away shells and undecorticated stones to the other end. The

speed of moving belt was optimized at 5 rpm, as increasing the speed of belt

caused mixing of the kernels and shells. The use of hopper with mixing assembly

allowed uniform discharge of the decorticated stone mass on the moving belt for

separation. Forced air draft on the moving belt provided separation of dust

particles as well as directed the flow of the shells towards the upper end for easy

separation (Plate 1). Data in Table 4.3 reveal that soaking of apricot stones or

decorticated stone mass brought about significant improvement in separation of

kernels through mechanical separator.

33

Table 4.3: Effect of soaking treatments on the efficiency of kernel separation in mechanical separator

Treatment*

Particulars

Time taken for separation

(min/kg)

Quantity of kernel separated (kg)

Rate of kernel

separation (Kg/min)

% Separation

1st

Pass 2nd

Pass 3rd

Pass Total in

mechanical separator

4th** Pass

Total

S1 Mechanical decortication without soaking followed by separation in salt solution (control)

0.60 5.80 5.80 0.48 100.0

S2 Soaking of apricot stones in water for overnight followed by decortication and kernel separation in mechanical separator

2.41 1.91 1.36 0.12 3.99 1.72 5.71 0.12 69.9

S3 Soaking of decorticated apricot stones mass in water for overnight followed by kernel separation in mechanical separator

2.50 2.30 1.20 0.12 4.20 1.58 5.78 0.13 72.7

S4 Mechanical decortication of pre-soaked apricot stones followed by further soaking of decorticated stone mass prior to separation in mechanical separator

2.12 2.58 1.34 0.14 4.60 1.25 5.85 0.14 78.6

CD (0.05) 0.06 - - - - - 0.057 0.024 0.19

NOTE: - * 20 kg of stones were used for each batch of experimentation. ** 4 th separation was carried out in 20% salt solution as in control.

34

Out of 20 kg apricot stones, 5.8 kg apricot kernels were obtained by using gravity

separation i.e. dipping decorticated stone mass in 20 per cent salt solution

followed by separation of kernels (control). For separation through mechanical

separator, the stones and decorticated mass after different soaking treatments

were placed in the hopper and allowed to roll on the rubberized belt moving in

the opposite direction. The material was passed through the belt for three times

(three passes). It was evident from the data that maximum separation of kernels

was obtained in first two passes (3.27-3.92 kg) and least (0.12 to 0.14 kg) in the

third pass to achieve complete separation. The left over material was separated by

dipping in salt solution, which was referred to as 4th pass. The soaking treatment

(S4) comprising of decortication of presoaked stones and further soaking of

decorticated stone mass exhibited higher quantity (4.60 kg) of kernels separated

through mechanical separator followed by S3 and S2 treatments. The efficiency of

kernel separation in S4 treatment was found to be 78.6 as against 72.7 per cent

and 69.9 per cent obtained in S3 and S2 treatments. Further, the time taken

(min/kg) for kernel separation through mechanical separator was the lowest in S4

treated stones (2.12 min/kg). Consequently, rate of kernel separation (kg/min)

was highest (0.14 kg/min) as compared to other two treatments. In comparison to

S2 and S3 soaking treatments, the decortication of presoaked stones followed by

further soaking (S4) exhibited highest amount of kernel separation (78.6 %)

through mechanical separator. Soaking of apricot stones prior to decortication

and re-soaking of decorticated mass brought about significant improvement in

kernel separation efficiency and reduced the time taken for separation of kernels

through the mechanical separator. The optimized method for mechanical

separation of kernels consisted of soaking of apricot-stones in water for overnight

followed by soaking of decorticated mass and separation through mechanical

separator having rubberized belt placed on 22.5o inclination for 1 to 3 passes

(Plate 1).

Thus, the mechanical separator can be used for separation of kernels from

mixed stones/ shells/kernel mass after soaking pretreatments of apricot

stones/kernel.

Apricot stones

Soaking in water (Overnight)

Removal of surface moisture

Decortication using mechanical decorticator

Further soaking of decorticated mass for overnight

Removal of surface moisture

Separation in mechanical separator

Fig. 1: Standardization of method for separation of apricot kernels from decorticated mass using mechanical separator

Fig: 3. Effect of pre-treatment on separation efficiency of apricot kernels in mechanical separator

Fig: 4. Effect of pre-treatment of apricot kernels on yield (%) of extracted oil for table oil expeller

100

0

20

40

60

80

100

120

S1

0

5

10

15

20

25

30

35

40

45

50

O1

46

treatment on separation efficiency of apricot kernels in separator

treatment of apricot kernels on yield (%) of extracted oil for

69.972.7

S2 S3 Treatment

O2 O3 O4 O5 O6

3840 41

3942

treatment on separation efficiency of apricot kernels in

treatment of apricot kernels on yield (%) of extracted oil for

78.6

S4

O7

43

35

4.2 Optimization of pretreatments of apricot kernels for improving yield and quality of oil

The effect of soaking of apricot kernels in water (5 and 10 % w/w) with or

without steaming on the yield of kernel oil through Table oil expeller was studied

and compared with oil yield obtained through Soxtec oil extractor using

petroleum ether as organic solvent. The data in Table 4.4 reveal that with the

increase in proportion of water in the kernels, the oil yield exhibited an increase

(40.0 and 41.0 %) at 5 and 10 per cent moisture content. The oil yield through

Table oil expeller from kernels without soaking (control) was found to be 38 per

cent which increased significantly to 40 and 41 per cent when water (5 to 10 %

w/w) was used for soaking of kernels. Further, steaming of kernels prior to oil

extraction brought about significant improvement in oil yield from the steamed

kernels (42.0 and 43.0 %). However, the difference in oil yield between 5 and 10

per cent water soaking was not significant. The press cake left after oil extraction

was proportional to the oil yield from respective treatments. Further, the residual

oil in the press cake ranged between 2.5 to 7.0 per cent with maximum oil

remaining in the press cake left after oil extraction of apricot kernels (7.0%)

without prior soaking and steaming (control). The treatment having minimum

(2.5 %) quantity of residual oil in cake and maximum (43.0 %) quantity of oil

expelled from Table oil expeller was considered optimum and most appropriate.

Thus, soaking of kernel by addition of 10 per cent water followed by steaming

(5 psi) for 15 minutes was considered optimum for achieving higher yield (43.0

%) of expressed oil with minimum (2.5 %) amount of residual oil in the press

cake. The moisture content in the kernels exhibited an expected pattern of

increase with the increase in addition of water content for soaking. However, the

kernels evaluated after steaming showed higher moisture content (13.5 %) than

those without steaming. The extracted oil also showed similar pattern of moisture

content ranging between 0.40 to 1.40 per cent in different treatments (Table 4.4).

However, the difference in oil yield by using 5 per cent or 10 per cent water for

soaking (Treatments O6 and O7) was not significant, as such even soaking of

kernels by using 5 per cent water can be considered appropriate.

36

Table 4.4: Effect of soaking, steaming and oil extraction methods on the yield and quality of apricot oil and press cake

Treatment

Particulars OIL YIELD (%)

PRESS CAKE YIELD

(%)

RESIDUAL OIL IN PRESS CAKE

(%)

MOISTURE

KERNELS (%)

OIL (%)

O1 Oil extraction in Soxtec oil extractor from apricot kernels without adding water

46.0 54.0 - 3.8 -

O2 Oil extraction in Table oil expeller from apricot kernels without adding water (control)

38.0 62.0 7.0 4.0 0.30

O3 Oil extraction in Table oil expeller after soaking by addition of 5% (w/w) water in apricot kernels

40.0 60.0 5.5 4.5 0.38

O4 Oil extraction in Table oil expeller after soaking by addition of 10% (w/w) water in apricot kernels

41.0 59.0 4.5 5.0 0.40

O5 Oil extraction in Table oil expeller after steaming of apricot kernels (5 psi) for 15 min without prior soaking in water

39.0 61.0 6.0 9.0 1.25

O6 Oil extraction in Table oil expeller after soaking by addition of 5% water in apricot kernels followed by steaming (5 psi) for 15 min

42.0 58.0 4.0 12.0 1.30

O7 Oil extraction in Table oil expeller after soaking by addition of 10% water in apricot kernels followed by steaming (5 psi) for 15 min

43.0 57.0 2.5 13.5 1.40

CD(0.05) 1.05 1.34 0.77 0.60 0.03

Wild apricot kernels (5 kg)

Addition of 10 per cent water (50 ml.)

Steaming (5 psi) for 15 min.

Cooling at room temperature to remove surface moisture

Extraction of oil in Table oil expeller

Oil filtration in oil filter press

Storage in coloured bottles for analysis

Fig 2: Standardization of method for extraction of oil from wild apricot kernels through Table oil expeller

37

4.2.1 Effect of pretreatments of apricot kernels on Physico-chemical characteristics of extracted oil

Data in Table 4.5 indicate that the visual colour of extracted oil after

different soaking and steaming treatments remained deep yellow, thus indicating

not much change in visual colour appearance with the use of treatments.

However, according to Tintometer colour evaluation, the yellow colour units in

different oils exhibited a decline (6.4 in control to 5.2 in O7). The oil extracted

after adding water showed lower yellow colour units (5.7) and slightly higher red

(0.3) and blue colour units (0.1). Further, steaming of apricot kernels also caused

decrease in yellow colour units (5.3-5.2) with increase in red (0.6-0.7) and blue

colour units (0.1). Thus, the study indicates that soaking and steaming treatments

did cause some change in colour units as compared to petroleum ether extracted

oil (control). However, broadly, the visual appearance of oil remained deep

yellow in colour.

The apricot kernel oil exhibited low acid value ranging from 2.27 to 2.77

mg KOH/g of oil. The oil extracted from solvent extraction method (O1)

possessed minimum acid value of 2.27 mg KOH/g of oil, while acid value was

found maximum in oil extracted after steaming treatment of kernels (O7). Thus,

extraction of oil in Table oil expeller with or without soaking and steaming

caused some increase in acid value as compared to solvent extracted oil. Iodine

value of apricot oil by using solvent extraction or Table oil expeller with or

without soaking and steaming treatments ranged between 100.2 to 100.6 gI2/100g

thus exhibiting no appreciable effect of different treatment combinations. Iodine

value representing degree of unsaturation of oil being an inherent character is not

expected to change with the method of extraction. Peroxide value representing

the quality of oil ranging between 5.12 to 5.27 meq/kg was affected by the

pretreatment of apricot kernels and method of extraction. Oil extracted through

solvent extraction had the minimum peroxide value (5.12 meq/kg) which

increased significantly to 5.18 meq/kg when the oil was extracted by using Table

oil expeller. Soaking of kernels in 5 to 10 per cent water prior to oil extraction

also caused increase in peroxide value of oil (5.21-5.22 meq/kg). Further,

steaming of kernels with or without soaking also brought some increase in

peroxide value of oil. However, the effect of using 5 or 10 per cent water for

38

Table 4.5: Effect of soaking, steaming and oil extraction methods from apricot kernels on the Tintometer colour units of extracted oil

Treatment Particulars Tintometer colour units (TCU) Visual colour appearance

Yellow Red Blue

O1 Oil extraction in Soxtec oil extractor from apricot kernels without adding water

6.4 0.2 0.0 Deep Yellow

O2 Oil extraction in Table oil expeller from apricot kernels without adding water (control)

5.8 0.4 0.1 Deep Yellow

O3 Oil extraction in Table oil expeller after soaking by addition of 5% (w/w) water in apricot kernels

5.7 0.3 0.1 Deep Yellow

O4 Oil extraction in Table oil expeller after soaking by addition of 10% (w/w) water in apricot kernels

5.7 0.3 0.1 Deep Yellow

O5 Oil extraction in Table oil expeller after steaming of apricot kernels (5 psi) for 15 min without prior soaking in water

5.3 0.6 0.1 Deep Yellow

O6 Oil extraction in Table oil expeller after soaking by addition of 5% water in apricot kernels followed by steaming (5 psi) for 15 min

5.2 0.7 0.1 Deep Yellow

O7 Oil extraction in Table oil expeller after soaking by addition of 10% water in apricot kernels followed by steaming (5 psi) for 15 min

5.2 0.7 0.1 Deep Yellow

39

Table 4.6: Effect of soaking, steaming and oil extraction methods from apricot kernels on the quality characteristics of extracted oil.

Treatment

Particulars

Quality attributes

Acid Value (mg KOH/g)

Iodine Value

(gI2/100g)

Peroxide Value

(meq/kg)

Saponification value

(mg KOH/g)

HCN in oil

(mg/100g)

HCN in press cake

(mg/100g)

Tocopherol content

(µg/g)

O1 Oil extraction in Soxtec oil extractor from apricot kernels without adding water

2.27 100.2 5.12 189.7

0.0

99.8 277.0

O2 Oil extraction in Table oil expeller from apricot kernels without adding water (control)

2.52 100.4 5.18 190.2

26.5

32.5 286.0

O3 Oil extraction in Table oil expeller after soaking by addition of 5% (w/w) water in apricot kernels

2.64 100.4 5.21 190.4

29.2

30.2 286.7

O4 Oil extraction in Table oil expeller after soaking by addition of 10% (w/w) water in apricot kernels

2.67 100.4 5.22 190.6

32.5

28.8 289.0

O5 Oil extraction in Table oil expeller after steaming of apricot kernels (5 psi) for 15 min without prior soaking in water

2.71 100.6 5.24 191.5

0.0

0.0 273.7

O6 Oil extraction in Table oil expeller after soaking by addition of 5% water in apricot kernels followed by steaming (5 psi) for 15 min

2.74 100.6 5.26 191.6

0.0

0.0 272.7

O7 Oil extraction in Table oil expeller after soaking by addition of 10% water in apricot kernels followed by steaming (5 psi) for 15 min

2.77 100.6 5.27 191.7

0.0

0.0 272.0

CD(0.05) 0.016 0.03 0.014 0.13 0.20 0.17 1.64

40

soaking was found non-significant with respect to its peroxide value.

Saponification value of apricot oil extracted by using solvent extraction or Table

oil expeller with or without soaking and steaming treatments ranged between

189.7 to 191.7 mg KOH/g. Statistically, though the difference in values were

significant between solvent extraction (control) and table oil expelled oil yet the

difference within soaking and steaming were not appreciable. Thus, the

saponification value was not affected much with the pretreatment of apricot

kernels. HCN content in the oil was also variable in different treatments. The use

of different pretreatments of apricot kernels brought about change in presence of

hydro-cyanic acid (HCN) in the extracted oil. Oil extracted through Soxtec oil

extraction apparatus did not show the presence of HCN while press cake left after

oil extraction exhibited highest content (99.8 mg/100g) of HCN. Similarly, in

case of oil extracted through Table oil expeller, the level of HCN content varied

according to the type of treatments used for oil extraction. Oil and press cake

obtained after steaming of kernels at 5 psi for 15 min did not show any presence

of HCN. While, the oil extracted through Table oil expeller after soaking of

kernels without steaming showed the presence of HCN. The HCN content in oil

and press cake from un-soaked kernels was 26.5 and 32.5 mg HCN/100 g

respectively and kernels soaked by using 5 and 10 per cent water exhibited 29.2

and 32.5 mg HCN/100g in oil and 30.2 and 28.8 mg HCN/100g in press cake

respectively (Table 4.6). Thus, steaming of kernels prior to oil extraction through

Table oil expeller was effective in removing the HCN content from oil as well as

press cake. The vitamin E content in oils ranged between 272 to 289 µg/g in oil

obtained from kernels after using different pre-treatments. Maximum tocopherol

content (289.0 µg/g) was found in oil obtained from expelling of pre-soaked

kernels in 10 per cent water (O4). As expected, steaming of kernels caused some

loss in vitamin E content of the extracted oil. Thus, on the basis of complete

removal of HCN content and minute changes in quality attribute of oil, the

extraction of oil through Table oil expeller after soaking and steaming of kernels

was found optimum for apricot oil extraction.

Fig: 5 Effect of pre-treatment of apricot kernels on the HCN content (mg/100g) of extracted oil and press cake

Fig: 6. Effect of pre-treatment of apricot kernels on the tocopherol content (µg/g) of extracted oil

0

26.5 29.232.5

0 0 0

99.8

32.5 30.2 28.8

0 0 00

20

40

60

80

100

120

O1 O2 O3 O4 O5 O6 O7

HCN in oil (mg/100g) HCN in press cake (mg/100g)

277

286 286.7

289

273.7272.7 272

260

265

270

275

280

285

290

295

O1 O2 O3 O4 O5 O6 O7

41

4.2.2 Effect of pretreatment of apricot kernels on the Fatty acid composition (% w/w) of extracted oil

Data presented in Table 4.7 indicate that apricot oil irrespective of

pretreatments and methods of extraction contained appreciable proportion of

unsaturated fatty acids (90.48-91.52 % w/w) as compared to only (8.61-8.87 %

w/w) saturated fatty acids. Among unsaturated fatty acids, monounsaturates

comprising of palmitoleic acid (C16:1) and oleic acid (C18:1) accounted for 62.34

to 64.79 per cent (w/w) in apricot oil from different treatments. Oleic acid (C18:1)

was the predominant monounsaturated fatty acid in the apricot oil (61.93-64.16 %

w/w). The oil was found to be good source of poly-unsaturated fatty acids

comprising of 25.66 to 27.61 per cent (w/w) linoleic acid (C18:2) and 1.02 to 1.47

per cent (w/w) linolenic acid (C18:3). The soaking and steaming treatments of

apricot kernels followed by oil extraction through Table oil expeller did cause

some change in the fatty acid composition of extracted oil. Among the oil

extracted through Table oil expeller (O2-O7), the level of palmitic acid (7.82-7.84

% w/w), palmitoleic acid (0.52-0.58 % w/w), stearic acid (0.97-1.03 % w/w) and

oleic acid (63.13-63.18 % w/w) was higher in oil extracted after soaking and

steaming of kernels (O5-O7 treatments). Thus, soaking and steaming of apricot

kernels prior to oil extraction was considered appropriate for extraction of oil

through Table oil expeller.

4.3 Standardization of method for utilization of apricot kernel press cake for extraction of volatile oil

The method for recovery of volatile oil from press cake left after oil extraction

from apricot kernel was standardized. On the basis of preliminary screening

dilution of press cake in water in 1:10 proportion was found most appropriate and

used for hydro-distillation in 10 litre capacity distillation apparatus. Further, out

of different fractions of distillate (100 ml, 200 ml, 300 ml, 400 ml and 500 ml)

collected from 10 litres of diluted press cake, it was found that maximum volatile

oil fragrance was found only in the first 100 ml distillate and used for further

experimentation. Data in table 4.8 reveal that 1.0 per cent distillate from 10 litres

of diluted press cake (1:10) contains 12 per cent benzaldehyde (Table 4.8).

42

Table 4.7: Effect of soaking, steaming and oil extraction methods from apricot kernels on the Fatty acid composition (% w/w) of extracted oil

Σ SFA - Sum of Saturated fatty acid Σ MUFA - Sum of Monounsaturated fatty acid Σ PUFA - Sum of Polyunsaturated fatty acid Σ UFA - Sum of Unsaturated fatty acid U:S Ratio - Unsaturated:Saturated ratio O1-O7 - Details of soaking, steaming and oil extraction methods shown in Table-2 (Chapter-3)

Sr. No. Fatty Acid Soaking, steaming and oil extraction method CD(0.05)

O1 O2 O3 O4 O5 O6 O7 1 Palmitic C16:0 7.61 7.69 7.70 7.73 7.82 7.83 7.84 0.012 2 Palmitoleic C16:1 0.63 0.41 0.42 0.46 0.52 0.56 0.58 0.013 3 Stearic C18:0

1.14 0.92 0.92 0.95 0.97 0.97 1.03 0.014 4 Oleic C18:1

64.16 61.93 61.95 61.97 63.13 63.17 63.18 0.030 5 Linoleic C18:2

25.66 27.71 27.65 26.63 26.55 26.51 26.49 0.021 6 Linolenic C18:3

1.02 1.47 1.45 1.42 1.16 1.15 1.12 0.015 7777

Σ SFA (1+3) 8.75 8.61 8.62 8.68 8.79 8.79 8.87 -

8888 Σ MUFA (2+4)

64.79 62.34 62.37 62.43 63.65 63.73 63.76 -

9999 Σ PUFA (5+6)

26.68 29.18 29.10 28.05 27.71 27.66 27.61 -

10101010 Σ UFA (2+4+5+6)

91.47 91.52 91.47 90.48 91.36 91.39 91.37 -

U:S Ratio (10/7) 10.45:1 10.63:1 10.61:1 10.42:1 10.39:1 10.39:1 10.30:1 -

43

Allowing the diluted press cake to macerate at 50 oC for overnight (T2) increased

the yield of benzaldehyde to 17.0 per cent in the first 100 ml distillate of

fractions. However, volatile oil also contained hydrocyanic acid (45.0 to 51.2

mg/100g) which is an undesirable. Data in Table 4.8 further indicate that re-

distillation of distillate up to 50 per cent of original volume in the laboratory

scale Clevenger’s apparatus resulted in appreciable improvement in benzaldehyde

content of the volatile oil. The benzaldehyde content increased after re-distillation

of distillate in treatments, T3 and T4 to 26.7 and 29.8 per cent from initial

concentration of 12.0 to 17.0 per cent.

Table 4.8: Standardization of method for extraction of hydro- distillate/volatile oil from apricot kernel press cake

Treatment Particulars Volatile oil yield

(ml)

Benzaldehyde (%)

Residual HCN (mg/100 ml)

Specific gravity of Volatile oil

T1 Diluting press cake with water (1:10) followed by distillation to collect 1 % distillate (100 ml)

100.0 (1.0%)*

12.0 45.0 1.042

T2 Diluting press cake with water (1:10) maceration at 50 °C for 12 hours followed by distillation to collect 1 % distillate (100 ml)

100.0 (1.0%)*

17.0 51.2 1.042

T3 Re-distillation of distillate (100 ml) from T1 with 3% each of CaO and FeSO4 to collect 50 % of volatile oil

50.0 (50%)*

*

26.7 0 1.045

T4 Re-distillation of distillate (100 ml) from T2 with 3% each of CaO and FeSO4 to collect 50 % of volatile oil

50.0 (50%)*

*

29.8 0 1.046

CD (0.05) 0.35 0.27 0.002

* Figure represents per cent of volatile oil obtained from distillation of total volume (10 litre)

** Figure represents per cent of volatile oil obtained after re-distillation of distillate T1 & T2 - 10 litre of diluted press cake (1:10) was used for distillation in

commercial distillation unit T3 & T4 - 100 ml of distillate was re-distilled in Clevenger’s apparatus

The highest concentration of benzaldehyde (29.8 %) was found in distillate

obtained after maceration of diluted press cake for 12 hours followed by mixing

of 3 per cent each of CaO and FeSO4 prior to re-distillation (T4). Further, addition

44

of 3 per cent (w/v) each of CaO and FeSO4 caused complete removal of residual

HCN in the re-distilled volatile oil. The volatile oil exhibited a specific gravity of

1.042 to 1.046. Thus, collection of 1 per cent distillate from the diluted press cake

(1:10) obtained after maceration (at 50 oC for 12 hours) and further collection of

50 per cent fraction (v/v) after re-distillation of distillate containing 3 per cent

each of CaO and FeSO4 was optimized for extraction of volatile oil from the

apricot press cake.

4.3.1 Anti-fungal activity of apricot volatile oil

Suitability of volatile oil from apricot kernel press cake was evaluated for

use as antimicrobial agent against different plant pathogenic fungi. Mycelial

growth rate of different plant pathogenic fungi was assayed by Poisoned Food

Technique in presence of different concentration of volatile oil to evaluate the in-

vitro fungicidal effect. Data in Table 4.9 indicate mycelial growth rate (mm/day)

of different plant pathogenic fungi as affected by different concentration of

volatile oil from apricot kernel press cake. The mycelial growth of Fusarium sp.,

Sclerotium sp. and Macrophomina sp. was recorded as 9.7, 9.0 and 9.8 mm/day

with mean value of 9.5 mm/day in control medium having no volatile oil. Use of

different concentration of volatile oil from apricot kernel press cake (5-20 %)

brought about significant effect on the mycelia growth rate of different fungi.

Table 4.9: Effect of different concentrations (%) of apricot press cake volatile oil on the mycelial growth rate of some plant pathogenic fungi

Volatile oil Concentration

(%)

Average mycelial growth (mm/day) Fusarium

sp. Sclerotium

sp. Macrophomina

sp. Mean

0.0 %

9.7 (18.1)

9.0 (17.5)

9.8 (18.2)

9.5 (17.9)

5.0 %

8.4 (16.8)

5.5 (13.6)

6.1 (14.3)

6.6 (14.9)

10.0 %

0.0 (0.0)

1.0 (5.7)

1.3 (6.5)

0.7 (4.1)

15.0 % 0.0 0.0 0.0 0.0 20.0 % 0.0 0.0 0.0 0.0 CD(0.05) 0.08 0.27 0.13 -

Values in parentheses indicate transformed values.

Left over press cake after oil extraction (1 kg)

Addition of water (10 kg)

Maceration at 50 oC for 12 hrs

Water distillation in volatile oil extraction apparatus

Collection of volatile oil (100 ml)

Addition of 3% each CaO and FeSO4

Re-distillation of distillate in Clevenger’s apparatus

Collection of volatile oil (50 ml) without HCN

Fig 3: Standardization of method for extraction of apricot volatile oil from left over press cake

Fig: 7. Benzaldehyde content of volatile oil from apricot kernel press cake

12

17

26.7

29.8

0

5

10

15

20

25

30

35

T1 T2 T3 T4

Benzaldehyde (%)

45

The mean growth rate (mm/day) at 5 per cent volatile oil concentration was found

to be 8.4 mm/day in Fusarium sp., 5.5 mm/day in Sclerotium sp. and 6.1 mm/day

in Macrophomina sp. While at 10 per cent volatile oil concentration the growth

rate was significantly reduced to 0.0 mm/day in Fusarium sp., 1.0 mm/day in

Sclerotium sp. and 1.3 mm/day in Macrophomina sp. Mycelial growth rate in

volatile oil concentration to be going 10 per cent i.e. 15 to 20 per cent was

recorded to be 0.0 mm/day. Statistically, the difference in growth rate at different

concentration of volatile oil found to be significant.

Further, it was revealed from the data (Table 4.10) that use of volatile oil

from apricot press cake exhibited a significant inhibitory effect on the mycelia

growth of different plant pathogenic fungi. Even 10 per cent concentration of

volatile oil was effective in bringing about 100 per cent inhibition in mycelia

growth of Fusarium sp. followed by 83.5 per cent in Macrophomina sp. and

98.06 per cent in Sclerotium sp. However, 100 per cent inhibition in mycelial

growth of all the three plant pathogenic fungi was observed when 15 per cent and

20 per cent concentration of volatile oil was used. Thus, it can be concluded that

15 per cent concentration of apricot press cake volatile oil can significantly be

used for inhibiting growth of Fusarium, Sclerotium and Macrophomina fungi.

The antifungal property of volatile oil of apricot press cake could be a potential

source of new antifungal agent and can be used as natural antifungal agent for

treatment of various skin diseases as well as for control of plant pathogenic fungi.

Table 4.10: Inhibitory effect of apricot press cake volatile oil against some plant pathogenic fungi

* Mycelial growth inhibition was measured after 7 days of incubation. Growth inhibition

was measured by using different concentration of apricot press cake volatile oil. Values in parentheses indicate transformed values.

Fungus sp.

Mycelial growth inhibition (%) at different concent rations after 7 days

5% 10% 15% 20% Fusarium sp. 31.8

(34.3) 100

(90.0) 100 100

Sclerotium sp. 61.4 (51.6)

83.5 (66.0)

100 100

Macrophomina sp. 52.44 (46.4)

98.06 (82.0)

100 100

CD (0.05) 0.07 0.10 - -

CHAPTER–5

DISCUSSSION

The present investigation entitled “Refinement of technology for

extraction and utilization of apricot kernel oil and press cake” was conducted in

the Department of Food Science and Technology, Dr. Y S Parmar University of

Horticulture and Forestry, Nauni, Solan, (H.P.) during the years 2010-2013. The

result of this study presented in tables 4.1-4.10 are discussed as under:

5.1 Development of method for mechanical separation of apricot kernels after decortication

The parameters like angle of static friction of apricot stones and kernels

on different surfaces of rolling belt and effect of soaking of kernels on size

parameters of kernels were standardize to design a mechanical separator for

separation of kernels from the decorticated apricot stone mass.

5.1.1 Optimization of coefficient of static friction

Angle of static friction (θ) of un-soaked and soaked wild apricot stones,

kernels, shells and decorticated mass (shells+kernels) was evaluated on four

surfaces viz. wood, glass, paper and rubber. On different surfaces, the angle of

static friction of apricot stones and kernels was found to be 20.0 to 22.8o on

wood, 9.6 to 14.0o on glass, 13.8 to 16.8o on paper and 22.2 to 25.3o on rubber

surface (Table 4.1). It was clear that the angle of static friction for all fractions of

apricot stones after soaking was more than the un-soaked stones. Soaking of

apricot stones brought about significant improvement on the angle of static

friction of stones and kernels. Earlier, Fathollahzadeh et al. (2008) also found

increase in angle of static friction on wood, fiberglass, glass and galvanize sheet

with the increase in moisture content of the apricot stones as well as kernels. The

mean value of soaked kernels was recorded as 21.0o on wood, 10.2o on glass,

14.5o on paper and 22.5o on rubber against 19.0o on wood, 9.0o on glass, 13.0o on

paper and 22.0o on rubber in un-soaked material. Similar to these findings,

Ahmadi et al. (2009) recorded lower angle of static friction on glass for apricot

shells and kernels as compared to wood, galvanize sheet and fiberglass sheet.

47

Jafari et al. (2011) also observed increase in angle of static friction of sunflower

seed with increase in moisture content from 5 to 25 per cent on mild and

galvanized steel sheet. Therefore, soaking of apricot stones and kernels prior to

separation was considered optimum. Further, in view of flexibility and static

friction, the use of rubberized belt with an inclination angle of 22.5o from base

was found appropriate for the mechanical separator. Thus, at 22.5o inclination

angle of the rubberized belt it was expected to allow the kernels to roll down on

opposite upward moving belt thereby separating kernels from the crushed stone

mass (kernels, shells and undecorticated stones).

5.1.2 Effect of soaking treatments on moisture and size parameter of apricot stones and kernels

As expected soaking thought about increase in moisture and size

parameters of the apricot stones and kernels (Table 4.2). Soaking of apricot

stones for overnight followed by re-soaking after decortication caused increase in

moisture content from 7.8 per cent to 20.6 per cent in stones and 4.4 per cent to

30.4 per cent in kernels. Initial moisture content was 7.8 per cent in stones and

4.4 per cent in kernels without soaking (control). Due to inhibition of moisture,

the size parameters like length, breadth, thickness, geometric mean diameter and

sphericity of stones and kernels also increased. The length of stones and kernels

before soaking (Control) was 20.0 mm and 12.0 mm which were found to

increase to 20.5 mm and 12.6 mm respectively after soaking treatment. Further,

the breadth of stones (15.9 mm) and kernels (9.0 mm) before soaking increased to

16.4 mm and 9.4 mm respectively after soaking. Thickness of stones and kernels

before soaking was 10.3 mm and 6.0 mm which increased to 10.6 mm and 7.0

mm after soaking respectively. With increase in length, breadth and thickness the

geometric mean diameter of stones and kernels after soaking was found as 15.3

mm and 9.4 mm respectively from initial value of 14.8 mm and 8.6 mm

respectively before soaking. Consiquently, with the increase in various size

parameters the sphericity of kernels also increased to 74.6 per cent after soaking

from the initial value of 72.1 per cent before soaking. The improvement in size

parameters of soaked apricot kernels was attributed to cellular inflation and

penetration of water in the porous area of kernels. In conformation to these

48

studies, Haciseferogullari et al. (2007) also found improvement in technological

properties of apricot fruits like length, diameter, geometric mean diameter,

sphericity, bulk density and static coefficient of friction with increase in moisture

contents.

Fathollahzadeh et al. (2010) recorded increase in sphericity of apricot

kernels from 62.2 to 62.9 per cent with increase in moisture content from 2.86 to

13.03 per cent.

Jafari et al. (2011) also found increase in surface area of sunflower seeds

of Shamshiri variety with the increase in moisture from 6.3 to 20 per cent.

Improvement in size parameters of kernels like length, breadth, thickness,

geometric mean diameter and sphericity after soaking are expected to make the

kernels more rolling on the upward moving rubberized belt, which will improve

their separation from the shells. Thus, soaking of apricot stones for overnight

followed by re-soaking after decortication was optimized for improving the size

parameters of apricot kernels to help in their separation through the mechanical

separator.

5.1.3 Mechanical separator for apricot kernels

Keeping in view the optimized rubber surface for allowing rolling, angle

of inclination of belt and improvement in physical properties of stones and

kernels by soaking, the mechanical separator for separation of apricot kernels was

developed. Out of different surfaces, the use of rubberized belt and it’s placement

in inclination position of 22.5o angle from the base was found optimum allowing

it to move in opposite direction. This arrangement allowed rolling of kernels to

lower end on the belt and carrying away shells and undecorticated stones to the

upper end. The speed of movement of belt on the mechanical separator was

optimized at 5 rpm, as increasing the speed of belt caused mixing of the kernels

as well as shells. The use of hopper with mixing assembly allowed uniform

discharge of the decorticated stone mass on the moving belt for separation.

Forced air draft on the moving belt provided separation of dust particles as well

as directed the flow of the shells towards the upper end for easy separation (Plate

1). Further, soaking of apricot stones followed by re-soaking of decorticated

stone mass significantly improved the separation of kernels.

49

Though, separation of kernels by dipping in 20 per cent salt solution

(gravity separation) yielded 5.8 kg kernels from 20 kg decorticated stone mass,

considered as complete separation. Yet, the kernels are known to absorb salt,

which is not considered appropriate for oil extraction purposes. Thus, mechanical

method was standardized for kernels separation.

For separation through mechanical separator, the stones and decorticated

mass after different soaking treatments were placed in the hopper and allowed to

roll on the rubberized belt moving in the opposite direction. The material was

passed through the belt for three times (three passes). It was evident from the data

that maximum separation of kernels was obtained in first two passes (3.27-3.92

kg) and least (0.12 to 0.14 kg) in the third pass to achieve complete separation.

The left over material was separated by dipping in salt solution, which was

referred to as 4th pass. The soaking treatment comprising of decortication of pre-

soaked stones and further soaking of decorticated stone mass (S4) exhibited

higher quantity (4.60 kg) of kernels separated through mechanical separator

followed by other two treatments viz. soaking of apricot stones prior to

decortications (S2) or soaking of decorticated stone mass (S3). The efficiency of

kernel separation in S4 treatment was found to be 78.6 as against 72.7 per cent

and 69.9 per cent obtained in S3 and S2 treatments. The increase in separation

efficiency was alternated to the improvement in size parameters of the kernels

viz. sphericity, geometric mean diameter, etc. which allow the kernels to roll on

the surface. Further, the time taken (min/kg) for kernel separation through

mechanical separator was the lowest in S4 treated stones (2.12 min/kg).

Consequently, rate of kernel separation (kg/min) was highest (0.14 kg/min) as

compared to other two treatments. Thus, mechanical separator can be used

successfully for separation of about 78.6 per cent kernels from decorticated

apricot stones to replace the use of gravity separation using salt solution.

Therefore, the optimized method for mechanical separation of kernels consisted

of soaking of apricot stones in water for overnight followed by re-soaking of

decorticated mass and separation through mechanical separator having rubberized

belt placed on 22.5o inclination for 1 to 3 passes was considered most

appropriate.

50

5.2 Optimization of parameters of apricot kernel for improving yield and quality of oil

Pre-treatment of apricot kernels like soaking in water with or without

steaming was evaluated for improving yield and quality of oil through Table oil

expeller. Out of different considerations, soaking of apricot kernels in 5-10 per

cent water followed by steaming (5 psi) for 15 minutes prior to oil extraction in

Table oil expeller brought about significant improvement in oil yield (43 %) as

compared to only 38 per cent oil found in untreated kernels. However, soaking

alone also caused increase in extracted oil (40-41 %) than without soaking but the

yield was lower than the oil extracted after soaking and steaming of kernels. The

residual oil in press cake left after oil extraction was found to be minimum (2.5

%) as compared to the other treatments. In conformation to these results Gupta

and Sharma (2009) recorded only 39-40 per cent oil in apricot kernels, extracted

without using pre-treatments. Sharma et al. (2005) obtained 43.03 per cent in

wild apricot kernels (chulli). The increase in oil recovery thought be attributed to

the releasing of oil from the oil bearing cells caused by soaking and steaming of

the kernels. Oil extracted through Table oil expeller (43 %) and oil actually

present in kernels (46 %) obtained by solvent extraction indicate that soaking and

steaming pre-treatments were capable to extract about 91.30-93.48 per cent oil

from kernels through Table oil expeller. Thus, soaking of kernels by addition of

10 per cent water followed by steaming at 5 psi for 15 minutes was optimized for

extracting higher oil yield (43 %) through Table oil expeller with minimum

amount of residual oil (2.5 %) in the press cake.

5.2.1 Physico-chemical characteristics of apricot kernel oil

The visual appearance of apricot oil extracted from kernels with or

without soaking and steaming treatments recorded deep yellow, thus indicating

not much change in appearance with the use of pre-treatments. Earlier, Sharma et

al. (2005), Gupta (2006) and Tilakaratne (2007) also observed visual yellow

colour in kernel oil from different apricot cultivars and in wild apricot kernel oil.

The tintometer colour units (TCU) also reflected yellowness as predominant

colour which ranged from 5.2 to 6.4 (TCU) in different treatments. Gupta (2006)

51

recorded yellow colour ranging between 5.7-6.9 TCU in apricot kernel oil from

different cultivars from different areas of Himachal Pradesh. Tilakaratne (2007)

recorded 6.8 TCU in bitter kernel oil and 5.7 TCU in sweet kernel oil. However,

soaking and steaming of kernels did cause some decrease in yellow colour units

and slightly higher red and blue colour units in the extracted oil. However,

broadly the visual appearance of oil was deep yellow and acceptable.

The acid value represents the amount of free fatty acid present in the oil

which is also used as an indicator of hydrolytic rancidity. The wild apricot kernel

oil after different pre-treatments exhibited low acid value (2.27 to 2.77 mg

KOH/g oil). Sharma et al. (2005) reported acid value ranging between 2.26-4.31

mg KOH/g oil in apricot kernel oil. Gupta (2006) and Tilakaratne (2007) also

recorded low acid value (2.27 to 2.78 mg KOH/g oil) and (2.28 mg KOH/g oil),

respectively. While Gupta (2006) recorded high acid value in sweet kernelled

apricot oil ranged between 4.27 to 4.35 mg KOH/g oil. According to FSSA

(2006) the acid value of oil shall not exceed 6.0 mg KOH/g oil. Therefore, the

acid value of apricot kernel oil obtained after soaking and steaming of kernels

was found well below the specified limit.

Iodine value defined as number of grams of iodine absorbed by 100 g of

the oil represents the degree of unsaturation in the oil. More the iodine value

more will be the unsaturation. The iodine value of oil extracted from apricot

kernel after different pre-treatments was ranged between 100.2 to 100.6 gI2/100 g

oil. Earlier, Gupta (2006) recorded iodine value in sweet and bitter apricot kernel

oils, ranging between 100.2 to 112.7 gI2/100 g oil. Tilakaratne (2007) also

observed the iodine value ranging between 100.3 to 110.4 gI2/100 g oil in apricot

kernel oil. Further, commercially sold refined, bleached and deodorized (RBD)

apricot oil also contained iodine value within the range of 100 to 112 gI2/100g

(Anonymous, 20012a). Therefore, the iodine value of oil obtained after soaking

and steaming of apricot kernels remained within the specified limit for apricot oil.

The peroxide value of apricot oil obtained after different pre-treatments of

kernels varied between 5.12 to 5.27 meq/kg oil. Similar to these results,

Tilakaratne (2007) recorded peroxide value of 5.28 meq/kg oil and 4.3 meq/kg oil

in bitter and sweet kernelled apricot oil. Gupta (2006) found peroxide value in

52

range of 5.12 to 5.26 meq/kg oil in bitter kernelled oil and 4.32 to 4.40 meq/kg in

sweet kernelled oil. However, soaking of apricot kernels followed by steaming

caused some increase in peroxide value. The level of peroxide value was found

well below the critical value of peroxides (125 meq/kg) specified for unsaturated

fatty acids (Jacobs, 1958). The commercially sold refined, bleached and

deodorized (RBD) apricot kernel oil was reported to have peroxide value of 8 to

10 meq/kg oil (Anonymous, 20012a). Therefore, soaking and steaming of apricot

kernels did not cause any adverse effect on the peroxide value of the extracted

oil.

Further, the saponification value of apricot kernel oil extracted by using

Solvent extraction or Table oil expeller with or without soaking and steaming

pre-treatments ranged between 189.7 to 191.7 mg KOH/g oil. Thus, in view of

the range of saponification value, the soaking and steaming did not cause any

adverse effect on the quality of the oil. Earlier, Tilakaratne (2007) and Gupta

(2006) recorded saponification values as 190.3 mg KOH/g oil and 189.8 mg

KOH/g oil in bitter and 190.3 mg KOH/g oil in sweet kernel oil, respectively.

According to FSSA, 2006 (Food Safety and Standard Act), the saponification

value of almond oil should be in the range of 186 to 195 mg KOH/g oil

(Anonymous, 2012a). Thus, the saponification value of the oil extracted after

soaking and steaming of apricot kernels remained well within the specified limit

of almond oil.

Wild apricot kernels are known to contain cyanogenic glucoside-

amygdalin which upon hydrolysis in presence of β-glucosidase yield hydrocyanic

acid (HCN) and cause bitterness in the kernels (Cheeke, 1998). Sharma et al.

(2005) recorded a value of 72 mg/100g in wild apricot kernels. However, oil

extracted from the apricot kernel contains comparatively very less value of the

bittering compounds on HCN is reported to be water soluble. In the present

investigations, oil and press cake obtained after passing the un-soaked apricot

kernels through Table oil expeller showed the presence of 26.5 and 32.5 mg

HCN/100g respectively. Soaking of kernels in 5-10 per cent water prior to oil

extraction through Table oil expeller exhibited increased level of HCN in oil

(29.2-30.2 mg/100g) and press cake (28.8-32.5 mg/100g). Increased level of

53

HCN in soaked apricot kernel oil was attributed the activation of inherent β-

glucosidase enzyme in the soaked kernels to cause hydrolysis of amygdalin to

release HCN. However, the oil extracted through solvent extraction did not show

the presence of HCN in oil while, press cake contained as high as 99.8 mg/100g

which was attributable to the volatile nature of HCN thus remaining only in the

press cake. Further, oil and press cake obtained after steaming of kernels at 5 psi

steam pressure for 15 minutes were completely free of HCN. This might be

attributed to the loss of HCN by steaming as HCN is reported to be water soluble.

Thus, steaming of apricot kernels can be considered a necessary pre-treatment for

extraction of oil which is completely free of bittering component (HCN).

Tocopherol (vitamin E) content in apricot kernel oil varied between 272.0

to 289.0 µg/g. Different workers found different levels of tocopherol in different

cultivar of apricot kernel oil. Tilakaratne (2007) reported the tocopherol content

varied between 430 to 438 µg/g in bitter and sweet kernelled apricot oil. Earlier,

Dutta et al. (1999) recorded the tocopherol content in apricot oil in the range of

268.5 to 436.0 µg/g. As expected, steaming of kernels caused some loss in

vitamin E content of the oil.

On the basis of physico-chemical characteristics and complete removal of

HCN in the oil method consisting of soaking apricot kernels in 5 to 10 per cent

water followed by steaming (5 psi) for 15 minutes prior to oil extraction through

Table oil expeller was found most appropriate.

5.2.2 Effect of pre-treatment of apricot kernels on the Fatty acid composition (% w/w) of extracted oil

The fatty acid present in the apricot kernel oil (Table 4.6) were found to

be as palmitic (7.61 to 7.84 %), palmitoleic (0.41 to 0.63 %), stearic (0.92 to 1.14

%), oleic (61.93 to 64.16 %), linoleic (25.66 to 27.71 %) and linolenic acid (1.02

to 1.47 %). It was found that apricot kernel oil irrespective of pre-treatments and

method of extraction possessed an appreciable proportion of unsaturated fatty

acid which comprised of 62.34 to 64.79 per cent monounsaturated fatty acid and

26.68 to 29.18 per cent polyunsaturated fatty acid. While saturates were only

ranging from 8.61-8.87 per cent thus the ratio between unsaturates and saturates

(U/S) was ranging from 10.45 to 10.63. Among the unsaturated fatty acids, oleic

54

acid (C18:1) and linoleic acid (C18:2) were the predominant acids in apricot kernel

oil. Soaking and steaming treatments of apricot kernels followed by oil extraction

through Table oil expeller did cause some changes in the fatty acid composition

of extracted oil. However, the ranges of fatty acids in the present investigation

were in agreement with earlier workers.

Tilakaratne (2007) recorded a value of 62.07 per cent oleic acid and 27.76

per cent linoleic acid in apricot kernel oil. Sherin et al. (1994) recorded a value of

68.88 per cent oleic acid and 15.77 per cent linoleic acid in kernel oil of NJA-13

apricot cultivar grown in Pakistan. According to Kapoor et al. (1987) the oleic

and linoleic acid content of different cultivars of apricot grown in Ladakh region

ranged between 50.95-83.33 per cent and 9.62-45.90 per cent respectively.

Similarly, kernel oil from Amar cultivar of apricot grown in Egypt was reported

to contain 66.29 per cent and 28.64 per cent of oleic and linoleic acid respectively

(Abd El-Aal et al. 1986). In wild apricot kernel oil presence of oleic and linoleic

acid was found 74.3 per cent and 21.6 per cent respectively (Aggarwal et al.

1974). The oil rich in polyunsaturated fatty acid have been shown to reduce the

risk of cardio vascular disease (Agar et al. 1995). Linoleic and linolenic acid are

essential fatty acids and are important for maintenance of skin, hair growth,

regulation of cholesterol metabolism and maintenance of cell integrity (Sardesai,

1997). Therefore, apricot kernel oil possesses special dietary importance and can

be used for edible and pharmaceutical purpose.

Thus, a method consisting of soaking (5-10 %) and steaming (5 psi, 15

min.) of apricot kernels prior to oil extraction in Table oil expeller resulting in

higher oil yield with no adverse effect on the quality and completely free from

HCN was optimized for apricot oil extraction at commercial scale.

5.3 Method for extraction and utilization of volatile oil from apricot kernel press cake

5.3.1 Standardization of method for extraction of volatile oil from apricot kernel press cake

Process protocol for extraction of volatile oil from press cake left after

expelling of apricot kernel oil through Table oil expeller was standardized.

Process optimization consisted of standardization of pre-treatment of press cake

55

slurry to allow maximum hydrolysis of inherent amygdalin to benzaldehyde and

HCN, collection of appropriate proportion of distillate having volatile oil and

removal of HCN from the distillate. On the basis of preliminary screening, the

dilution of press cake in water in 1:10 proportion was found appropriate for use

in distillation as lower dilution resulted in slurry of very thick consistency and

most suitable for distillation purpose. Out of different fractions of distillate (100

ml, 200 ml, 300 ml, 400 ml and 500 ml) obtained from distillation of press cake

slurry, collection of first 100 ml (1 % of slurry) contained the maximum volatile

oil with 12 per cent benzaldehyde (T1). Allowing the diluted press cake slurry to

macerate at 50 oC for overnight (T2) followed by distillation caused increase in

benzaldehyde to 17 per cent is in first 100 ml distillate (Table 4.8). However, the

distillate also contained hydrocyanic acid (45.0-51.2 mg/100g) which is an

undesirable component in the volatile oil. This increase in benzaldehyde along

with HCN in distillate upon maceration of slurry was attributable to the activation

of amulsin (an inherent β-glucosidase enzyme) known to be present in the press

cake slurry, which react upon the amygdalin during maceration and released

benzaldehyed, HCN and glucose (Liener, 1966). Therefore, first distillate

contained both benzaldehyde as well as HCN. Re-distillation of distillate up to

first 50 per cent of original volume in Clevenger’s apparatus was found

appropriate in increasing the concentration of benzaldehyde in the distillate (T3)

to 26.7 to 29.8 per cent (T3 & T4) from initial concentration of 12 to 17 per cent.

As expected the highest concentarion of benzaldehyde (29.8 %) with no residual

HCN was found in the distillate obtained after maceration of diluted press cake

for 12 hours followed by mixing of 3 per cent each of FeSO4 and CaO prior to re-

distillation (T4). According to Gildmeister and Holfmann (1974) the addition of 3

per cent (w/v) each of FeSO4 and CaO in the distillate caused precipitation of

HCN as insoluble calcium ferro-cyanide, thereby making the re-distilled volatile

oil completely free of HCN.

In conformation to these results, Tilakaratne (2007) reported that re-

distilling of 3.31 per cent volatile oil after addition of CaO and FeSO4 in distillate

contained as high as 89.0 per cent benzaldehyde without any HCN. Gildmeister

and Holfmann (1974) also recorded 0.5 to 0.7 per cent volatile oil from bitter

56

almond and 0.6 to 1.8 per cent from apricot kernels. Thus, the method consisting

of maceration of press cake slurry (1:10) at 50 oC for overnight followed by

distillation of 10 litres slurry in volatile oil distillation apparatus to collect 1 per

cent distillate and re-distillation of distillate in Clevenger’s apparatus (50 %) after

addition of 3 per cent each of FeSO4 and CaO was optimized to obtain volatile oil

completely free of HCN for use as flavourant.

5.3.1 Antifungal activity of apricot volatile oil

The volatile oil obtained after hydro-distillation of macerated apricot

kernels press cake slurry (1:10) for overnight at 50 oC was evaluated for anti-

microbial properties. It was found that volatile oil considerably checked the

mycelial growth rate (mm/day) of different fungi. The initial mycelial growth rate

of Fusarium sp. (9.7 mm/day), Sclerotium sp. (9.0 mm/day) and Macrophomina

sp. (9.4 mm/day) without use of volatile oil (Control) was reduced to 8.4 mm/day

(Fusarium sp.), 5.5 mm/day (Sclerotium sp.) and 6.8 mm/day (Macrophomina

sp.) when 5 per cent volatile oil was used in the growing medium. Significant

reduction in mycelial growth rate ranging between 0.0-1.3 mm/day was observed

when 10 per cent volatile oil was used while use of volatile oil beyond 10 per

cent brought about complete check in the mycelial growth (Table 4.9). In view of

statistically insignificant difference in 15 and 20 per cent concentration, the use

of 15 per cent volatile oil was considered optimum for checking the growth of

three used fungi. Reduced mycelial growth rate of different fungi by use of

volatile oil was probably attributed to the presence of HCN content in the volatile

oil. In conformation to these observations Lechtenberg and Nahrstedt (1999)

reported the discovery of structure of HCN-librating compounds in bitter

almonds by Robiquet and Boutron-Chalard in 1830 which possessed anti-

microbial activity. This compound was named as amygdalin as it was isolated

from Prunus amygdalus. According to Franks et al. (2005) diglucosidase

amygdalin was the first measure to be isolated as a natural product called as

cyanogenic glucosides found in many plant species, upon disruption of plant

tissue containing cyanogenic glucosides, these are hydrolysed by β-glucosidase

with concomitant release of glucose, an aldehyde or ketone and hydrocyanic acid

(HCN). Thus, the presence of HCN content in the apricot press cake volatile oil

57

might be attributed to the inhibition of mycelial growth in plant pathogenic fungi.

It was further revealed from the study (Table 4.10) that the one of volatile oil

exhibited significant inhibitory effect on the mycelial growth of different fungi.

Application of 10 per cent volatile oil brought about 100 per cent inhibition in

mycelial growth in Fusarium sp. followed by 83.5 per cent in Macrophomina sp.

and 98.06 per cent in Sclerotium sp. However, complete inhibition of mycelial

growth of the three plant pathogenic fungi was found when 15 per cent or more

concentration of volatile oil was used. According to Espinel-Ingroff et al. (2002)

and Dellavalle et al. (2011) the minimum fungicidal concentration (MFC) refers

to the lowest concentration that inhibits the fungal growth on the solid medium.

Thus, the use of 15 per cent volatile oil is considered to be the minimum

fungicidal concentration (MFC) of apricot volatile oil for all the three plant

pathogenic fungi. In conformation to these results Feminia et al. reported that

bitter apricot seed posses stronger and broader spectrum of anti-microbial activity

due to the presence of some metabolic toxins or broad spectrum anti-biotic

compounds. Thus, it can be concluded that 15 per cent concentration of apricot

kernel press cake volatile oil can significantly be used for inhibiting growth of

Fusarium, Sclerotium and Macrophomina sp.

Therefore, the anti-fungal property of volatile oil of apricot press cake

could be potential source of new and natural anti-fungal agent for treatment of

various skin diseases as well as control of plant pathogenic diseases.

CHAPTER–6

SUMMARY AND CONCLUSION

Studies on “Refinement of technology for extraction and utilization of

apricot kernel oil and press cake” were conducted in the Department of Food

Science and Technology, Dr. Y S Parmar University of Horticulture and Forestry,

Nauni, Solan (H.P.) during the years 2010-2013. Wild apricot stones left after

utilization of edible portion were procured in bulk from Karsog area in Mandi

district of Himachal Pradesh (1850 meter above mean sea level) and brought to

the Department of Food Science and Technology. The wild apricot stones before

or after pretreatments were decorticated using mechanical decorticator with

separating sieves (M/S Kisan Krishi Yantra Udyog Kanpur, India), specially

designed and modified for decortication of apricot stones. Mechanical separator

was developed by optimizing parameters like rolling surface of belt, soaking

pretreatments of apricot stones/kernels, speed of rolling belt, feeding conveyer

and forced air draft for separation of kernels and shells from the decorticated

stone mass. Steaming pre-treatments of apricot kernels with or without addition

of water was optimized for extraction of oil through Table oil expeller (M/S

Sardar Engineering Co, Kanpur, India). The press cake left after oil extraction

was utilized for extraction of volatile oil after pretreatment of press cake slurry.

The method for extraction of volatile oil from press cake was standardized using

Volatile oil distillation unit and Clevenger’s apparatus. The anti-microbial

properties of press cake based volatile oil were studied against Fusarium sp.,

Sclerotium sp. and Macrophomina sp. The results of these studies on various

aspects are summarized briefly as under:

1. Angle of static friction (θ) of soaked stones, kernels, shells and mixture of

shells as well as kernels on different rolling surfaces was more than the

un-soaked stone fractions. The highest angle of static friction was found

on rubber based rolling surface. Thus, the use of rubberized belt and

soaking of stones/kernels with an inclination angle of 22.5o was optimized

59

and adopted for use in development of mechanical separator for apricot

kernels.

2. Soaking of apricot stones/kernels affected the length, breadth, thickness,

geometric mean diameter and sphericty of stones and kernels. As the

moisture content of stones and kernels increased, the size parameters of

stones and kernels also increased. Size parameters of kernels such as

length (12.0 mm), breadth (9.0 mm), thickness (6.0 mm), geometric mean

diameter (8.6 mm) and sphericity (72.1 %) were increased to 12.6 mm,

9.4 mm, 7.0 mm, 9.4 mm and 74.6 per cent respectively, after soaking

treatments. Study of physical properties of apricot stones and kernels were

used in designing of equipments for kernel separation.

3. Soaking of stones/kernels before and after decortication improved the

efficiency of kernel separation in mechanical separator. Decortication of

pre-soaked apricot stones followed by further soaking of crushed stone

mass was found optimum for separation of apricot kernels with 4.60 kg of

kernels from 20 kg of crushed mass out of 5.85 kg of total kernel yield in

three passes. The kernel separation efficiency of Mechanical separator

was worked out to 78.6 per cent.

4. Steaming of apricot kernels with or without addition of water brought

about improvement in yield and quality of oil extracted through Table oil

expeller. Soaking of kernels by addition of 10 per cent water followed by

steaming (5 psi) for 15 min was considered optimum for achieving higher

yield (43.0 %) of expressed oil with minimum (2.5 %) amount of residual

oil in press cake.

5. Visual colour of extracted oil after different soaking and steaming

treatments remained deep yellow, thus indicating not any adverse change

in visual colour. However, according to Tintometer colour evaluation, the

yellow colour units in different oils exhibited a decline (6.4 in control to

5.2 in oil from moistened and steamed kernels). Apricot kernel oil

exhibited low acid value ranging from 2.27 to 2.77 mg KOH/g of oil.

Iodine value of extracted oil by using solvent extraction or Table oil

expeller with or without soaking and steaming treatments ranged between

60

100.2 to 100.6 g I2/100 g. Peroxide value ranged between 5.12 to 5.27

meq/kg was affected by the pretreatment of apricot kernels and method of

extraction. Steaming of kernels with or without soaking brought some

increase in peroxide value in the oil (5.24-5.27 meq/kg). Saponification

value of apricot oil extracted by using solvent extraction or Table oil

expeller with or without soaking and steaming treatments ranged between

189.7 to 191.7 mg KOH/g.

6. Oil extracted through soxtec oil extraction apparatus did not show the

presence of hydrocyanic acid (HCN) while press cake left after oil

extraction exhibited highest content (99.8 mg/100g) of HCN. Oil and

press cake obtained after steaming of kernels at 5 psi for 15 min did not

show any presence of HCN. However, oil extracted through Table oil

expeller after soaking of kernels without steaming showed the presence of

HCN.

7. The vitamin E content in oils ranged between 272-289 µg/g. Maximum

tocopherol content (289.0 µg/g) was found in oil obtained from expelling

of pre-soaked kernels in 10 per cent water. As expected, steaming of

kernels caused some change in vitamin E content of the extracted oil.

8. The soaking and steaming treatments of apricot kernels followed by oil

extraction through Table oil expeller did cause some change in the fatty

acid composition of extracted oil. Among the oil extracted through Table

oil expeller, the level of palmitic acid (7.82-7.84 % w/w), palmitoleic acid

(0.52-0.58 % w/w), stearic acid (0.97-1.03 % w/w) and oleic acid (63.13-

63.18 % w/w) was higher in oil extracted after soaking and steaming of

kernels.

9. Collection of 1 per cent distillate from 10 litres of diluted press cake

(1:10) obtained after maceration at 50 oC for 12 hours followed by

collection of 50 per cent distillate after re-distillation of distillate

containing 3 per cent each of CaO and FeSO4 was optimized for

extraction of volatile oil from the apricot press cake which contained

29.77 per cent benzaldehyde without HCN.

61

10. The volatile oil exhibited inhibitory properties against mycelial growth of

some plant pathogenic fungi viz. Fusarium sp., Sclerotium sp. and

Macrophomina sp. The antifungal property of volatile oil of apricot press

cake could be a potential source of new antifungal agent against plant

diseases. Thus, 15 per cent concentration of apricot press cake volatile oil

can significantly be used for inhibiting growth of Fusarium sp.,

Sclerotium sp. and Macrophomina sp.

CONCLUSION

It can thus, be concluded from the present investigations that mechanical

separator having rubberized belt placed at an inclination angle of 22.5o moving in

upward opposite direction can be used for separation of kernels from pre-soaked

wild apricot kernel mass with about 78.6 per cent separation efficiency with no

apprehension of presence of salt in the kernels. Further, overnight soaking of

apricot kernels in 10 per cent water followed by steaming (5 psi) for 15 min can

be used as a pretreatment for extraction of oil through Table oil expeller with

about 43 per cent oil yield with complete removal of HCN from the oil. The press

cake left after oil extraction can also be utilized for extraction of volatile oil with

29.8 per cent benzaldehyde for its use in various formulations viz. flavourant,

antifungal agent etc. The method consisting of maceration of press cake slurry

(1:10) at 50 oC for 12 hrs followed by distillation to collect 1 per cent distillate

and its maceration along with 3 per cent each of CaO and FeSO4 to obtain about

50 per cent of the distillate was optimum for hydro-distillation of volatile oil. The

anti-fungal property of volatile oil of apricot kernel press cake could be a

potential source of new natural anti-fungal agent against plant diseases caused by

Fusarium sp., Sclerotium sp. and Macrophomina sp.

Thus, use of mechanical separator for separation of apricot kernels,

soaking and steaming of apricot kernels for extraction of oil in Table oil expeller

to improve yield and quality of oil and extraction and utilization of volatile oil

from left over press cake can be adopted by the entrepreneurs on a cottage scale.

CHAPTER – 7

REFERENCES

Abd El Aal M H, Khall N K M and Rehman E H. 1986. Apricot kernel oil

characterization, chemical composition and utilization in baked products.

Journal of Food Chemistry. 19(4): 287

Agar I I, Sarminato C, Ciarces R, Kaska N, Kafkas S and Ali B E. 1995. Compositional changes of fatty acids during the development of embryo in Pistana vera. Acta Horticulturae. 419: 405-410

Aggarwal K K, Bedi K L and Khalid M. 1974. Commercial utilization of wild

apricot kernels. Journal of Oil Technology Association, India. 6(3): 67-69

Ahmadi H, Fathollahzadeh H and Mobli H. 2009. Post harvest physical and

mechanical properties of apricot fruits, pits and kernels (cv. Sonnati Salmas)

cultivated in Iran. Pakistan Journal of Nutrition. 8(3): 264-268

Alam S M. 2001. Physico-chemical characteristics, fatty acid composition and

oxidative stability of some seed kernel oils of Prunus. Journal of Agricultural

Sciences. 32(1): 37-47

Anonymous. 2012. Area and production of fruits in Himachal Pradesh. Department of Horticulture, H.P. Shimla-2

Anonymous. 2012a. Important information on rancidity and vegetable oils. The Nutrition Farm. www.nutritionfarm.com

AOAC. 1995. Official methods of analysis. Association of Official Analytical Chemists, 16th ed. (Cd. 41). Association of Official Analytical Chemists, Washington DC. pp 1-53

Bachheti R K, Rai I, Joshi A and Rana V. 2012. Physico-chemical study of seed oil of Prunus armeniaca L. grown in Garhwal region (India) and its comparison with some conventional food oils. International Food Research Journal. 19 (2): 577-581

Brower L P. 1969. Ecological Chemistry. Scientific American. 220 (2): 22-29

63

Chakaraborty M M and Talapatra K. 1965. Oils and Fats: General method for oil and fats. Indian Journal of Chemistry. 3 (11): 518.

Cheeke P R. 1998. Natural Toxicants in Foods, Forages and Poisonous Plants. Interstate Publishers, Inc. Danvilla, IL.

Ciulei I, Ghihaia A and Betiu N. 1973. Chemical study of the seeds of Prunus armeniaca var. communis. Farmacia. 21(6): 356

Cochran W G and Cox C M. 1967. Experimantal Designs. John Willey and Sons. Inc; New York.

Cruess W V. 1958. Commercial Fruit and Vegetable Products. McGraw Hill Co.,

New York. pp. 734-767

Dang R L, Narayanan R and Rao P S. 1964. Kumaon apricot kernel oil; its composition and utilization. Indian Oil Seed Journal. 8 (2): 110-115

Dellavalle P D, Cabrera A, Alem D, Larranaga P, Ferreira F and Rizza M D. 2011. Antifungal activity of medicinal plant extracts against phytopathogenic fungus Alternaria spp. Chilean Journal of Agricultural Research 71 (2): 231-239

Dhar K L and Chauhan R N S. 1963. Oil from seed kernels of Prunus armeniaca. Agricultural University Journal Research. 12: 1-9

Dixit A K, Sharma P C, Nanda S K and Kudos S K. 2010. Impact of processing

technology in hilly region: a study on extraction of apricot kernel oil.

Agricultural Economics Research Review. 23: 405-410

Dutta P C, Savage G P and Mcneil D L.1999. Fatty acids and Tocopherol contents and and oxidative stability of walnut oils. Journal of American Oil Chemists Society. 76(9): 1059-1063

Dwivedi D H and Dwivedi S K. 2007. Traditional method of chuli oil extraction in Ladakh. Indian Journal of Traditional Knowledge. 6 (3): 403-405

Eckey E W. 1954. Vegetable Fats and Oils. Reinhold Publishing Corporation, New York. pp. 1-458

Espinel-Ingroff A A, Fothergill J, Peter M G, Rinaldi and Walsh T J. 2002. Testing conditions for determination of minimum fungicidal concentrations of new and established antifungal agents for Aspergillus sp: NCCLS Collaborative Study. Journal of Clinical Microbiology 40: 3204-3208

64

FAO. 2011. FAO Production Yearbook. Food and Agriculture Organization, Rome. www.fao.org.in

Fathollahzadah H, Mobli H, Beheshti B, Jafari A and Borghei A M. 2010. Effect of moisture content on some physical properties of apricot kernels (cv. Sonnati Salmas). Agricultural Engineering International: the CIGR Ejournal. 08: 08

Fathollahzadeh H. Mobli H. Jafari A. Rafiee S and Mohammadi A. 2008. Some physical properties of tabarzeh apricot kernel. Pakistan Journal of Nutrition. 7(5): 645-651

Fatma A Y, Yildirim A N, Askin M A and Kankoia A. 2010. Total oil, fatty acid composition and tocopherol content in kernels of several bitter and sweet apricot cultivars from Turkey. Journal of Food, Agriculture and Environment. 8(3-4): 196-201

Femenia A, Rossello C, Mulet A and Canellas J. 1995. Chemical composition of bitter and sweet apricot kernels. Journal of Agriculture and Food Chemistry. 43(2): 356-361

Franks T K, Hayasaka Y, Choimes S and Heeswijck R. 2005. Cyanogenic glucosides in grapevine: Polymorphism, identification and development patterns. Phytochemistry. 66: 165-173

FSSA. 2006. FSSAI Regulations. Ministry of Health and Family Welfare. Government of India, New Delhi.

FSSAI. 2012. Oils and Fats. In: Manual of methods of analysis of foods. Ministry of Health and Family Welfare. Government of India, New Delhi.

Gildmeister and Hoffmann. 1974. “ Die Atherichen ole”. 3rd edition, Vol-II. p. 844

Gomez K A and Gomez A A.1984. Statistical Procedures for Agricultural Research. 2nd ed. John Willey and Sons, New York. pp 1-240

Gupta A and Sharma P C. 2009. Standardization of technology for extraction of wild apricot kernel oil at semi-pilot scale. Biological Forum – An International Journal, 1(1): 51-64

Gupta A. 2006. Standardization of method for oil extraction from apricot kernels. M.Sc. Thesis, Dr. Y. S. Parmar University of Horticulture and Forestry, Solan (H.P.), India. pp. 1-95

65

Haciseferogullari H, Gezer I, Ozcan M M and Asma M B. 2007. Post harvest

chemical and physical-mechanical properties of some apricot varieties

cultivated in Turkey. Journal of Food Engineering. 79: 364-373

Hallabo S A S, Wakeil F A, Morsi M K S and Wakeil F A El. 1985. Chemical and physical properties of apricot kernel oil and almond kernel oil. Egyptian Journal of Food Science. 3(1-2): 1-6

Hammer K A, Carson C F and Riley T V. 1999. Anti-microbial activity of essential oil and other plant extracts. Journal of Applied Microbiology. 6(8): 985-989

Handoo S K, Bagga K K and Aggarwal T N. 1992. Properties of ground nut mustard and sunflower mustard oil blends. Journal of Oil Technologists Association of India. 24 (4): 123-136

Iordanidow P, Voglis N, Liadakis G N and Tzia C. 1999. Utilisation of apricot processing wastes. Acta Horticulturae. 488: 609-614

Jacob M B. 1958. The chemical analysis of Food and Food Products. 3rd ed. D Van Nastrand Co; Inc, Princeton, Toronto, New York. p. 970

Jafari S, Khazaei J, Arabhosseini A, Massah J and Khoshtaghaza M H. 2011. Study on mechanical properties of sunflower seeds. Electronic Journal of Polish Agricultural Universities. 14 (1): 06

Jain R K and Bal S. 1997. Physical properties of pearl millet. Journal of Agricultural Engineering Research. 66: 85-91

Kamboj P. 2002. Extraction and evaluation of stone fruit kernel oils. M.Sc. Thesis, Dr. Y. S. Parmar University of Horticulture and Forestry, Solan (H.P.).

Kapoor N, Bedi K L and Bhatiya A K. 1987. Chemical composition of varieties of apricot and their kernels grown in Ladakh region. Journal of Food Science and Technology. 24: 141-142

Lechtenberg M and Nahrstedt A. 1999. Cyanogenic Glucosides. In: Naturally Occuring Glucosides. Ikan, R.(Ed), John Wiley and Sons, Chichester, UK, ISBN:978-0-471-98602-7. pp. 147-191

Liener I E. 1966. Cyanogenic glucosides. In: Toxicants Occurring Naturally in Foods. NRC Publishers, Washington D C. pp. 1-58

Mayer L H. 1987. Food Chemistry. CBS Publishers and Distributers, New Delhi. pp. 12-64

66

McCarty C D, Lesley J V and Frost H B. 1952. Bitterness benzaldehyde content of kernels of Almond-Peach fruit hybrids and their parents. Proceedings of American Society for Horticultural Journal of Science Food and Agriculture. 59: 254-258

Metcalfe L D, Schmitz A A and Pelker J R. 1966. Rapid preparation of fatty acid for gas chromatographic analysis. Analytical Chemistry. 33: 363-364

Mohsenin N N. 1970. Physical properties of plant and animal material. Gordon and Breach Science Publication, New York.

Nawar W W. 1985. Lipids In: Food Chemistry. (ed. O R Fernnema) Marcel Dekker Inc, New York. pp. 139-244.

Ozcan M M, Ozalp C, Unver A, Arslan D and Dursun N. 2010. Properties of apricot kernel and oils as fruit juice processing waste. Food and Nutrition Sciences. 1: 31-37

Parmar C and Sharma A K. 1992. ‘Chuli’ – a wild apricot from Himalayan cold desert region. Fruit Varieties Journal. 46(1): 35-36

Pearson D. 1976. The Chemical Analysis of Foods. J. A. Churchill, London.

Polat R, Aktas T, Gezer I, Atay U and Bilim H I C. 2007. Breaking of apricot

pits by using a mechanical system. Journal of Applied Sciences. 7(8): 1158-

1163

Ranganna S. 2009. Handbook of Analysis and Quality Control for Fruit and Vegetable Products. 3rd edn. Tata McGraw Hill Pub. Co. Ltd., New Delhi, India.

Reddy D V, Azeemoddin G and Reddy D. 1995. A hand operated decorticator for

apricot nuts. Journal of Oil Technology Association, India. 27(4): 225-228

Rodriquez R, Aggarwal P C and Sana N K. 1971. Physico-chemical charactaristics of apricot varieties of Kumaon region and their suitability for canning. Indian Food Packer. 25: 5-10

Sardesai H. 1997. The essentials fatty acids. Nutritional Clinical Practical. p. 179

Savage G P, McNeil D L and Datta P C. 2001. Some nutritional advantages of Walnut. Acta Horticulturae. 544: 557-560

67

Sharma P C, Kamboj P, Kaushal B B Lal and Vaidya D. 2005. Utilization of stone fruit kernels as a source of oil for edible and non-edible purpose. Acta Horticulturae. 696: 551-557

Sharma P C, Sharma R and Kamboj P. 2003. Methodology for extraction of kernel oil. Practical Manual (NATP), Dr. Y. S. Parmar UHF, Nauni, Solan (H.P.)

Sharma, S.D. 1994. Variation in local apricots in district Kinnaur of Himachal Pradesh. Fruit Variety Journal. 48(4): 225-228

Sherin I, Azra Y, Khan M R and Sufi N A. 1994. Fatty acid composition of

apricot kernel oil. Sarhad Journal of Agriculture Science. 9(2): 113-116

Stosic D, Gorunovic M and Popovic B. 1987. Preliminary toxicological study of the kernel and oil of several species of the genus Prunus. Planter Medicinales-el-Phytotherapie. 21(8): 8-13

Thimmaiah S K. 1999. Lipids and Fats. In: Standard methods of Biochemical Analysis. Kalyani Publishers, New Delhi. pp. 130-150

Tilakratane B M K S. 2007. Studies on utilization of kernel oil and press cake of apricot for value addition. M.Sc. Thesis, Dr. Yashwant Singh Parmar University of Horticulture and Forestry, Solan (H.P.).

Vincent J M. 1947. Distortion of fungal hyphae in the presence of certain inhibitors. Nature. 150: 850

Winton A L and Winton K S. 1959. The structure and composition of foods. New York: John Wiley. p. 482

Yigit D, Yigit N and Mavi A. 2009. Anti-oxidant and anti-microbial activities of bitter and sweet apricot kernels. Brazilian Journal of Medical and Biological Research. 42: 346-352

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Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan (HP) Department of Food Science and Technology

Title of Thesis : Refinement of technology for extraction and

utilization of apricot kernel oil and press cake Name of student : Himanshu Sharma Admission number : H-2010-22-M Major advisor : Dr. P. C. Sharma Major Field : Food Technology Minor Field(s) : i) Food Sci. & Tech. (Group-I)

ii) Food Sci. & Tech. (Group-II) Degree Awarded : M.Sc. Food Technology Year of Award of Degree : 2013 No. of pages in Thesis : 68+ No. of words in Abstract : 465

ABSTRACT

Technology for mechanical separation of apricot kernels, improvement in oil extraction and utilization of volatile oil from press cake for control of plant pathogens was evaluated and refined. Out of different rolling surfaces, the use of 22.5o inclination angle on rubberized belt was found optimum for separation of kernels in mechanical separator. The size parameters of apricot kernels after soaking increased. Geometric dimensions such as length (12.0 mm), breadth (9.0 mm), thickness (6.0 mm), geometric mean diameter (8.6 mm) and sphericity (72.0 %) of apricot kernels was recorded to increase to 12.6 mm, 9.4 mm, 7.0 mm, 9.4 mm and 74.6 per cent respectively after soaking treatment. Besides, soaking of stones or decorticated stone mass brought about significant improvement in separation of kernels through mechanical separator with 78.6 per cent separation efficiency. Steaming of kernels at 5 psi for 15 min after addition of 10 % water brought about significant improvement in oil yield extracted through Table oil expeller. Further, the quality characteristics of oil from steamed kernels ranging between 2.27-2.77 mg KOH/g acid value; 100.21-100.63 g I2/100g iodine value; 5.12-5.27 meq/kg peroxide value and saponification value 189.67-191.73mg KOH/g oil, were found within the specification as laid under Food Safety and Standard Act for almond oil. Besides, steaming of kernels caused complete removal of residual HCN from extracted oil and left over press cake. The oil also contained 272.0-277.0 µg/g vitamin E, which is regarded as natural anti-oxidant and make the oil suitable for cosmetic and pharmaceutical purpose. The oil was found rich in unsaturated fatty acid containing oleic (61.93-64.16 % w/w) and linoleic (25.66-27.71 % w/w) as the major fatty acid, fractions with only 8.61 to 8.87 per cent saturated fatty acids. The press cake left after oil extraction was found suitable for the extraction of volatile oil for various purposes. For extraction of volatile oil, the method consisting of maceration of press cake in water (1:10) at 50 oC for 12 hrs followed by extraction of 1 % distillate and re-distillation of distillate in 3 % each of CaO and FeSO4 followed by collection of 50 % of volatile oil with 29.8 % benzaldehyde was optimized. The volatile oil possessed good anti-fungal properties against some plant pathogenic fungi like Fusarium sp, Sclerotium sp and Macrophomina sp. At 15 % volatile oil concentration, 100 % mycelial growth inhibition was recorded in all the three fungi. Therefore, anti-fungal property of volatile oil of apricot kernel press cake could be a potential source of new natural anti-fungal agent against plant diseases caused by Fusarium sp, Sclerotium sp and Macrophomina sp. Thus, complete technology for mechanical separation of kernels, steaming of kernels for oil extraction and hydro-distillation of volatile oil from press cake can be adopted at commercial scale for utilization of apricot stones by the entrepreneurs.

Signature of Major advisor Signature of student

Countersigned

\

Professor and Head Department of Food Science and Technology

Dr. Y. S. Parmar University of Horticulture and Forestry Nauni, Solan-173 230 (H.P.)

AP

PE

ND

IX-I

AN

OV

A fo

r ef

fect

of s

oaki

ng tr

eatm

ents

of d

ecor

ticate

d ap

ricot

sto

ne fr

actio

ns o

n th

e an

gle

of s

tatic

fric

tion

(θ)

of s

tone

s, k

erne

ls, s

hells

an

d m

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f she

lls a

nd k

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ollin

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of

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F

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Mea

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m o

f squ

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Sto

nes/

Pits

K

erne

ls

She

lls

She

lls+

Ker

nels

Un-

soak

ed

Soa

ked

Mea

n

Un-

soak

ed

Soa

ked

Mea

n

Un-

soak

ed

Soa

ked

Mea

n

Un-

soak

ed

Soa

ked

Mea

n

Tre

atm

ent

3 15

1.15

14

1.15

14

5.83

17

1.25

16

4.55

16

7.41

14

5.83

15

5.83

15

0.42

16

1.15

17

2.50

166

.74

Err

or

16

0.53

0.

56

0.34

0.

38

0.64

0.

26

0.50

0.

25

0.26

0.

72

0.3

1 0.

23

Tot

al

19

- -

- -

- -

- -

- -

- -

AN

OV

A fo

r ef

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of s

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on

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19

- -

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-

ii

AN

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A fo

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of s

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effici

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167

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Tot

al

19

- -

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AP

PE

ND

IX-I

I

AN

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A fo

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oil e

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and

pre

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il

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atm

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6 21

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49

.810

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986

Err

or

14

0.35

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7 0.

111

0.00

2

Tot

al

20

- -

- -

-

ii

i

AN

OV

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of s

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team

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and

oil e

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from

apr

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of e

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oil.

Sou

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De

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ares

Aci

d

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valu

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Per

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Sap

onifi

catio

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lue

HC

N in

oil

HC

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pre

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ophe

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cont

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Tre

atm

ent

6 0.

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Tot

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atm

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Tot

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20

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2 23

5.14

7 44

7.40

6 E

rror

6

0.00

1 0.

003

Tot

al

8 -

-

CURRICULUM VITAE

Name : Himanshu Sharma

Father’s Name : Sh. Ved Prakash

Date of Birth : 31st Dec, 1987

Sex : Male

Marital Status : Unmarried

Nationality : Indian

Educational Qualifications:

Certificate/ degree Class/ grade

Board/ University Year

10+2 First HP Board of School Education.

2006

B.Sc. (Horticulture) First Dr.Y.S.P. Univ. Of Horticulture & Forestry

Nauni- Solan

2010

Whether sponsored by some state/ : NA

Central Govt./Univ./SAARC

Scholarship/ Stipend/ Fellowship, any : University Stipend

other financial assistance received

during the study period

(Himanshu Sharma)