Ph D. Thesis Abstracts Name of student : Bal Vipan Chander (H-87-11-D) Year of completion of degree : 1991 Name of Major Advisor : Dr. S K Chopra Title of the thesis : Studies on ethylene management and storage of packaged apple (Malus domestica Borkh) cv. Red Delicious.

Abstract The present studies on ethylene management and storage of packaged apple (Malus

domestica Borkh.) cv. Red Delicious, were conducted in the Department of Post Harvest Technology, Dr YS Parmar University of Horticulture and Forestry, Solan (H.P.) during 1989-90 and 1990-91.The study was divided into three experiments. Experiment 1 relates to the effect of preharvest sprays of ethylene inhibitors/fungicide and experiment 2 and 3 to the post harvest application of fungicides, wax coating and ethylene scrubbers on fruit quality at harvest and during extended storage. The preharvest sprays were given 10 and 15 weeks after full bloom.The physiological loss in weight (PLW) and volume during storage were the lowest in fruits given preharvest sprays of AgNO3 100 ppm and Benzothiadiazole 100 ppm; or post harvest dip in Frutox 6% + DPA 1500 ppm. Fruits packed in CFB carton alongwith the sachets of Purafil/KMnO4 crystals also recorded the lowest PLW and volume loss. Similarly, the retention of flesh firmness during and at the end of 210 days storage was highest in these treatments. Control fruits on the other hand recorded the highest loss in weight, volume and flesh firmness.The ethylene evolution and respiration rates of the fruits reached a peak value at 60 to 90 days of storage under different treatments. However, the pack as more prominent and was achieved earlier (after 60 days) in control fruits as compared to the treatments with AgNO3 (50, 100 ppm), Benzothiadiazole (50, 100 ppm); post harvest application of Frutox 6% + DPA 1500 ppm and in fruits packed alongwith Purafil or KmnO4 sachets, in which the peak was recorded after 90 days in storage.The total soluble solids (TSS), total sugars, and reducing as well as non-reducing sugars, in general, increased with the advance in storage period upto 150 days and thereafter a continuous decline was observed towards the close of sampling. In experiment 1, the highest TSS content at the end of 210 days storage was observed in fruits treated with cycloheximide 50 ppm in experiment 2 and 3 fruits treated with Rovral 500 ppm or enclosed with the sachets of vermiculite impregnated with KmnO4 recorded the highest TSS contents.The titratable acidity in general declined with the advance ins torage period. The preharvet application of Bavistin 1500 ppm; or propylgattate 300 ppm; or the post harvest application of Frutox 6% + DPA 1500 ppm or the use of sachets containing Purafil/KmnO4 crystals resulted in the highest titratable acidity in fruits at the end of storage. The pH of the juice registered an increase with the advance in storage period. The electrical conductivity (EC) of the fruit, in general was low in the beginning, increased during the early period of stoage to reach a peak at 150 days and declined thereafter till the end of 210 days storage.Preharvest application of

AgNO3 (100 ppm) or Benzothiadiazole (100 ppm) or post harvest application of Frutox (6%) + DPA (1500 ppm) or enclosing fruits with sachets of Purafil/KmnO4 crystals resulted in higher pectin and juice content as compared to control. Total phenols showed a declining trend commensurate with the advance in storage period. Fruits given preharvest sprays of Bavistin (1500 ppm) or post harvest application of Bavistin (1500 ppm) or DPA (1500 ppm) and those enclosed with the sachets of Al-silicate impregnated with KmnO4 recorded the highest content of total phenols on all the sampling dates. These treatments also reduced the percent rotting of fruits during storage.The preharvest application of cyclohemimide (75 ppm) or post harvest dip in Frutox (6%) + DPA (1500) or fruits enclosed with the sachets of Purafil recorded a gradual, rather steady increase or decrease, in soluble protein content compared to control. The preharvest application of ethylene inhibitors or the post harvest application of fungicides and the use of sachets containing KmnO4 impregnated porous material suppressed the activity of fruits softening enzymes (Polygalacturones, Pectin metholesterage, cellulase) and respiratory enzyme (Malic dehydrogenage).In general, the preharvest apploication of AgNO3, Benzothiadiazole and postharvest application of Frutox (6%) + DPA (1500) or the use of Purafil and KmnO4 sachets proved quite effective in extending the shelf life of Red Delicious apple fruit by about a month or more over the control.

Name of student : Narayan Singh Thakur (H-88-12-D) Year of completion of degree : 1993 Name of Major Advisor : Dr B B Lal Kaushal Title of the thesis : Evaluation studies on commercial varieties and promising hybrids of Tomato grown in Himachal Pradesh for processing.

Abstract The present investigations were carried out to screen out the commercial varieties and

new promising hybrids of tomato grown in Himachal Pradesh for processing on the basis of their fruit characteristics, after preparation of different products and their storage behaviour. Six commercial varieties like Solan Gola, Yashwant, Money Maker, Punjab Chhuhara, Roma and Pusa Ruby and six new promising F1 hybrids like Vaishali, Rupali, Rajani, ARTH-4, MTH-6 and MTH-15 were grown in the vegetable research farm of the University at Pandah. All the package of practices were followed to raise the crop as recommended by the University. Fruits after harvesting at tree ripe stage were brought to the laboratory where different physico-chemical characteristics were determined and the products like juice, puree, paste, ketchup and whole fruit canning were determined from different varieties/hybrids and were evaluated on the basis of different physico-chemical, microbiological and sensory characteristics as fresh as well as at different storage intervals at ambient temperature storage.Among all the varieties/hybrids MTH-6 proved its superiority over other treatments with respect to most of the physico-chemical characteristics of the fruits. However, on the basis of these desirable chemical characteristics the

preferene in decreasing order for remaining varieties/hybrids was Yashwant, Rupali, Solan Gola, Pusa Ruby, Vaishali, ARTH-4, Roma, MTH-15, Rajani, Punjab Chhuhara and Money Maker. On the basis of physico-chemical, micro biological and sensory evaluation point of view different products as fresh as well as after storage at ambient temperature in different containers, Solan Gola, MTH-6, Rupali and Yashwant varieties/hybrids were found to be suitable for juice making, MTH-6, Rupali, Rajani, MTH-15 and Vaishali gave ketchup of best quality. However, the fruits of Rupali, MTH-6, Rajani, MTH-15, Roma and Vaishali could successfully be canned. Products quality was retained better and for longer period in glass bottle as compared to laminated pouch and HDPE container. From economic point of view, MTH-6 and Rupali were the best hybrids which could give the best products with minimum cost.

Name of student : Sanjay Chadha (H-88-13-D) Year of completion of degree : 1993 Name of Major Advisor :         Dr. S K Chopra Title of the thesis : Standardization of maturity indices of some cultivars of Olive (Olea europaea L.) in relation to oil extraction and table use in processed form.

Abstract The present investigations on the standardization of maturity indices of four olive

cultivars-Balenquat, Coratina, Manzanillo and Pendolino in relation to oil extraction and table use were carried out in the Department of Post Harvest Technology, Dr Y.S.Parmar University of Horticulture and Forestry, Solan during the year 1990 and 1991. Fruit was obtained from the Olive Development station, Panarsa (1300 msl) in Mandi District. The investigations were carried out in an experiment assigned to a block of twelve 17 year old trees (three for each cultivar). The fruits were picked on nine dates at weekly intervals progressively, commencing from 8th September and ending on 3rd November.The days from full bloom to harvest and fruit colour proved to be fairly reliable indices of maturity for oil extraction in all the four cultivars studied. The fruits accumulated optimum quantity of oil when the surface colour changed from green to black. The DFFB to harvest for oil extraction from the fruits of the cultivars Balenquat, Coratina, Manzanillo and Pendolino ranged from 195/192 to 202/199, 172/177 to 179/184, 194/196 to 201/203 and 166/171 to 180/185 respectively during 1990/91.The oil quality was not found to vary significantly with picking maturity. After one year storage of oil, however, acid and peroxide values registered a marked increase. Oil obtained from green fruits was observed to be more susceptible to oxidative deterioration in comparison to oil from coloured olives.Fruit colour proved to be the most reliable maturity index fro table olives. Green olives pickled when the fruit colour changed to light green recorded the highest organoleptic scores. Black olives were best pickled when the colour change fromg reen to purple or violet, depending on the cultivar, took place. Fruit size, pulp; stone ratio and oil content also proved to be fairly reliable indices of maturity for harvesting table olives.The fruit acidity, pH, ash, total protein and moisture content however, were not found to be dependable indices of maturity.Among the

cultivars studied, Manzanillo, Coratina and Pendolino were found suitable for both oil extraction and table use. However, Balenquat fruits were not suited for table purposes.

Name of student : Nardev Kumar Thakur (H-91-8-D) Year of completion of degree : 1997 Name of Major Advisor : Dr B B Lal Kaushal Title of the thesis : Debittering of kinnow juice on pilot scale for preparation of concentrate and its evaluation.

Abstract The present investigations were undertaken in the Department of Post Harvest

Technology, Dr Y.S.Parmar University of Horticulture and Forestry, Nauni, Solan during 1993-94 and 1994-95. The bitterness in kinnow juice was attributed to the presence of limonin and naringin. The highest limonin content was observed in seed, whereas, naringin content was more in peel than juice and seed. For clarification purpose treatment of juice with 0.8% pectinolytic enzyme at 40+1oC for 4 hours was found best. Of the different methods used for debittering adsorptive method of bitterness removal was found most successful. Amberlite XAD-16 debittered kinnow serum was reconstituted into debittered juice having good consumers acceptability by addition of 15% pulp and the juice was blended to 16oB with sugar alongwith orange essence @0.015%. The debittered kinnow serum was successfully converted into concentrate of 72oB and this concentrate packed in glass container with or without SO2 was stored upto 6 months at 18+1oC without much changes in its quality. After 6 months of storage the concentrate was converted into juice, calcium fortified juice and carbonated beverage successfully. The cost of production of debittered juice was found lowest for juice from fruits treated with 20 ppm ethylene, followed by XAD-16. Of the different juice/RTS beverages prepared from concentrate, carbonated beverage had the lowest cost of production.

Name of student : Anju Bhat (H-95-8-D) Year of completion of degree : 2000 Name of Major Advisor : Dr S N Tripathi Title of the thesis : Evaluation of Post Harvest Handling Methods for Carnation and Gladiolus Cut Flowers.

Abstract Cut flowers have always remained an integral part of social fabric of human life. Since

cut flowers have a limited shelf life, pulsing polyethylene packaging, refrigerated storage and transportation contribute to extension of shelf life besides regulating market supply of quality material. Pulsing treatment of cut flowers with silver thiosulfate and sucrose significantly increased vase life, fresh weight and diameter reduced weight loss, delayed ethylene production

and improved quality. Addition of 50 ppm BA to 4mm STS + 10% sucrose further improved vase life to 14.60-14.52 days in carnation compared to 8.40-8.52 days in control. In gladiolus also the vase life (12.43-12.60 days) and number of fully open florets (15.20-15.16) was maximum in the same pulsing treatment. STS acts as an ethylene antagonist, BA maintains petal turgidity for an extended period and sucrose fulfills the requirements for a carbohydrate source. Packaging of pulsed flowers of carnation in 300 gauge PE maintained flowers in acceptable condition in refrigerated storage upto 23 and even after 5 days of storage flower quality was like of unstored ones. Likewise in gladiolus floer spikes remained in acceptable condition in refrigerated storage upto 15 days. However flower quality deteriorated after 3 days of storage in ZECC and only after 1 day under ambient condition. When placed in holding solutions after removal from different storages at periodic intervals there was reduction in subsequent vase life and diameter of flowers as the storage period advanced. Further there was reduction in total sugar content and increase in PLW. Flowers transported after pulsing and packaging were of better quality with no mechanical injury as compared to conventional ones.

Name of student : Jagdish Chand Bhardwaj (H-95-9-D) Year of completion of degree : 2000 Name of Major Advisor : Dr V K Joshi Title of the thesis : Evaluation of some plum cultivars for production of sparkling wine by “Methode Champenoise” using biological deacidification and foam stability.

Abstract Six plum cultivars viz. Green Gage, Methley, Kanto-5, Santa Rosa, Frontier and

Meriposa were investigated for production of sparkling wine and standardization of various parameters and characteristics desirable for evaluation. On the basis of the analysis of plum wine prepared by using Schiz.pombe yeast, it can be concluded that pectinase enzyme can be added at any state as preclarifying agent for must or at the time of fermentation but adding at later stage is economically viable. A concentration of 200 ppm sodium benzoate as antimicrobial agent was found best for moderate rate of fermentation, optimum concentration of TSS, reducing sugars, ethanol and anthocyanin in the wine. Immobilization of yeast did not significantly affect the chemical characteristics of wine but had the advantage over liquid culture as it can be removed when desired. Addition of immobilized S. cerevisiae followed by Schiz. Pombe was found best treatment for production of base wine on account of chemical and sensory analysis. Addition of yeast extract during secondary fermentation gave better sparkling plum wine over control on account of higher foam life, foam expansion, higher soluble proteins and anthocyanin content and higher sensory evaluation score. Although Meriposa, Santa Rosa and Frontier were found superior cultivars over others for sparkling wine production on the basis of chemical characteristics and sensory evaluation scores, yet none was found unsuitable.

Name of student : Shashi Bhushan (H-97-30-D) Year of completion of degree : 2002 Name of Major Advisor : Dr V K Joshi Title of the thesis : Apple Pomace Utilization for the Production of Baker’s Yeast: Process Optimization, Evaluation and Performance.

Abstract Industrialization of horticulture sector no doubt assured economic prosperity but brought

along with it a huge quantity of fruit processing waste, whose disposal in the environment caused not only extensive pollution but also the loss of natural wealth. Apple pomace is a left-over residue after apple juice extraction amounting to about 20-30 per cent of the total processed apple fruits. To utilize this waste, the present study was undertaken to produce baker’s yeast (Saccharomyces cerevisiae var. diastaticus) with the objective of standardization of fermentation process, optimization of the growth parameters, performance evaluation of produced haker’s yeast is standardized along with different process parameters, with a Bio-Flow Fermentor-2000, NBS, having Advanced Fermentation Software. Among the different sugar concentration, 5 per cent was found optimum for higher biomass yield. A concentration of 20 per cent dissolved oxygen (DO) with agitation between 50-450 rpm, temperature of 30oC and pH of 4.5 in the medium gave the highest biomass yield during variable fed batch cultivation. About seven to nine times multiplication of initial inoculum of baker’s yeast was observed in apple pomace medium. The specific growth rate (u) of 0.24 hr-1 and average cellular yield coefificient (CYC) of 0.48g/g sugar consumed was achieved with the optimized parameters. The overall biomass yield recorded was 96 per cent to that of total theoretical yield. Drying of extruded yeast strands at 40oC for 4-5 hrs produced ADY of optimum leavening activity and cell viability having attractive creamish colour. The morphological characteristics and dough raising capacity (DRC) of the baker’s yeast produced on apple pomace was similar to that of commercially marketed yeast. The concentration of trehalose was found optimum for its performance as baker’s yeast. The performance of experimental yeast in production of different bakery products was comparable to that of commercial yeast. The estimated cost of experimentally produced baker’s yeast was found 30-33 per cent lower than commercial yeast and 20-25 per cent less than that of traditionally employed substrate i.e. Molasses. It is concluded that apple pomace can be a cheaper substrate for the production of Baker’s Yeast and simultaneously preventing the loss of natural resources and pollution.

Name of student : Narotam Kumar Kaushal (H-97-29-D) Year of completion of degree : 2002 Name of Major Advisor : Dr B B Lal Kaushal

Title of the thesis : Studies on juice extraction, clarification and preparation of carbonated beverages from apple and pear fruits.

Abstract The present investigations entitled “Studies on juice extraction, clarification and

preparation of carbonated beverages from apple and pear fruits”, were carried out in the Department of Post Harvest Technology, Dr Y.S.Parmar University of Horticulture and Forestry, Nauni-Solan (HP) during 1999-2000 and 2000-2001. In case of apples, macerating enzyme treatment comprising of pectinase and cellulase in 3:1 ratio applied @0.04 per cent at room temperature (20-25oC) for 2 hours resulted in the highest juice yield (18.63 to 20.00% higher compared to control). In case of pears, macerating enzyme treatment with pectinase alone @ 0.04 per cent at room temperature (20-25oC) for 2 hours resulted in the highest juice yield (22.2 to 23.3% higher compared to control). Both apple and pear fruit juices recorded the maximum clarification with the enzyme treatment containing pectinase and amylase in 1:1 ratio used @0.02 per cent at 50oC for 2 hours. For the preparation of carbonated beverages from apple juice, pear juice and reconstituted apple juice (from AJC), TSS of 14oB (with fixed acidity of 0.25%) and CO2 gas pressure of 80 psi were found to be the optimum. Carbonation also seem to improve the overall sensory quality of the apple, pear and reconstituted apple juice beverages. Among different blends of apple juice or constituted apple juice with pear juice, a ratio of 1:1 was found to be optimum for the preparation of carbonated fruit juice beverages which could be regarded as a limit for maximizing pear juice utilization without affecting the overall sensory quality of the carbonated apple and pear fruit juice beverage. All the five carbonated fruit juice beverages (from apple juice, pear juice, reconstituted apple juice and their 1:1 blends) showed good storage stability for a period of 9 months from nutritional, microbiological and sensory quality point of view, However, as per sensory evaluation, carbonated beverage from reconstituted apple juice was found to be the best which could be produced profitably even by selling at a price 35 per cent lower than the synthetic carbonated soft drinks available in the Indian Market.

Name of student : Anil Kumar Verma (H-97-28-D) Year of completion of degree : 2003 Name of Major Advisor : Dr B B Lal Kaushal Title of the thesis : Effect of Pre and Post Harvest Treatments on the Vase Life of Chrysanthemum (Dendranthema grandiflora Tzvelev).

Abstract The present investigations were undertaken in the Department of Post Harvest

Technology, Dr Y.S.Parmar University of Horticulture and Forestry, Nauni, Solan (H.P.) during the years 1999-2000 and 2000-2001. Chrysanthemum which occupies 2nd position in the international flower trade has been known to be used for interior decoration, garden display, in garland, religious offering and as a potted plant, beside as cut flower. In Himachal Pradesh due to earliness in flowering in Chrysanthemum its cultivation is becoming popular. The objectives of present investigations were to ascertain the effect of fertilizer does of Nitrogen and Potassium and influence of post harvest treatments i.e. use of holding and pulsing solutions, pre-cooling, packaging, storage and transportation on different growth parameters and vase life alongwith physico-chemical characteristics. Data on plant height, stem length, stem diameter, flower, diameter and weight of flower stem of Chrysanthemum cv. Snow Ball showed that 40g N/m2 alongwith 20gm K/m2 is the best dose for optimum growth and development of plant. However, interaction effect of Nitrogen and Potassium levels did not show significant effect on number of days taken to bud formation and days taken to reach the harvest stage. Studies carried out revealed that vase life of Chrysanthemum cut flowers decreased with increased level of Nitrogen and 2% sucrose + 200 ppm 8-Hydroxy Quinoline Citrate (8-HQC) was the best holding solution. However, maximum flower size opening was recorded in treatment combination 40g N/m2 alongwith 20g K/m2 evaluated in 2% sucrose + 200 ppm 8-HQC. For providing extra energy to Chrysanthem cut flowers, pulsing with 200 ppm 8-HQC + 5% sucrose treatment for 16 hrs was found best. Of different methods of storage and packaging treatments used for evaluating vase life and other physico-chemical characters, the treatment cold storage with wax paper wrapping at 24 hrs storage duration was found best followed by Zero Energy Cool Chamber. Pre-cooling flowers down to 4oC immediately after harvesting followed by transportation by refrigerated van resulted in maximum vase life and fresh like appearance for longer time. To get better post harvest behaviour immediately after harvesting, the flowers should be precooled 4oC, pulsed (200 ppm 8HQC + 5% sucrose for 16 hrs), packed in wax paper wrappers and finally stored in cold storage or transported in refrigerated van (4oC +2) to the terminal markets.

Name of student : Satish Kumar (H-99-18-D) Year of completion of degree : 2003 Name of Major Advisor : Dr B B Lal Kaushal Title of the thesis : Preparation and evaluation of lemon juice concentrates and powders.

Abstract Lemon cultivar Hill Lemon (Citrus pseudolimon Tan.) fruits grown in Himachal Pradesh

were evaluated for the preparation of some value added products like concentrates, juice powder and instant lemon beverage. Lemon juice extracted through rosing machine was clarified using

0.2 per cent Pectinase CCM enzyme for 2 hours at 50+2oC followed by filtration under suction. The treatment of lemon juice with glucose oxidase enzyme or charcoal were not found feasible for removal of sugars and amino acids (browning reaction substrates) respectively, while the use of cation exchange resin was found highly effective as it removed about 96.79 per cent amino acids thus was optimized. The temperature of 50+2oC was found optimum for concentration of lemon juice in Bucchi type vacuum evaporator as it caused minimum browning, development of furfural and hydroxymethyl furfural (HMF). Evaporative concentration of lemon juice upto 60oBrix was found optimum wityh maximum retention of various quality attributes. The cation exchange resin treatment caused about 3.28 folds reduction in browning when concentrated upto 60oBrix. The storage of concentrates prepared both from untreated and treated lemon juices brought about some increase in furfural, HMF and browning with consistent loss of sugars, ascorbic acid, amino acids and phenols. During storage, furfural, HMF and browning of concentrates prepared from treated juice were about 6.94, 40.68 and 3.85 folds less as compared to their untreated counterparts. Also the retention of ascorbic acid, amino acids and phenols was higher in concentrates of treated juice as compared to those from untreated juice. The changes in various physico-chemical characteristics of concentrates stored at refrigerated temperatures were lesser as compared to those stored at ambient temperatures. The retention of quality attributes was better in concentrates stored at refrigerated temperatures were lesser as compared to those stored at ambient temperatures. The retention of quality attributes was better in concentrates of 45 and 60oBrix than in the concentrate of 71oBrix. Sensory evaluation of lemon squashes prepared from reconstituted concentrates at different storage intervals indicated better acceptability of concentrates of treated juice than their untreated counterparts. Microbiological examination of lemon juice concentrates of both types of juices indicated good storage stability upto 9 months at both the temperatures under study. On the basis of foaming, drying characteristics and browning, the lemon juice concentrate of 60oBrix was found better than 45, 50 and 55oBrix concentrates, for the preparation of foam mat dried powders. Among the various foaming agents used to prepare powder from 60oBrix lemon juice concentrate, carboxymethyl cellulose @ 2.0 per cent was found best in terms of foaming and drying characteristics. Humidity moisture equailibrium studies reveal that lemon juice powders can safely be stored at relative humidities upto 21.36 per cent at room temperatures. During storage upto 9 months, the lemon juice powders prepared both from untreated and treated lemon juices exhibited loss in sugars, ascorbic acid, amino acids, phenols with consequent increase in furfural, HMF and browning. Further, changes in furfural HMF and browning were reduced by 2.63, 19.83, 3.94 folds and the retention of ascorbic acid increased by 1.59 times in the powders prepared from treated juice than untreated counterparts. Also, the juice powders prepared after adding 50% sugar showed better retention of quality attributes during storage than of powders stored without added sugar. The cation exchange resin treatment of lemon juice resulted in better retention of sensory attributes of juice powders during storage. Comparison of brahmi syrup, apple jam, and jelly prepared from lemon juice powder and citric acid, using triangle difference test indicated non-significant differences between the respective products. The costs of production were worked out

to Rs.99.90, Rs.154.29 and Rs.33.72 per kg of concentrate (60oBrix), juice powder and instant lemon beverage respectively. The cost of 1 litre of instant beverage was Rs.5.46. Thus, the manufacture of juice concentrates, powder and instant lemon beverage from hill lemon fruits seems to be a profitable proposition for the efficient utilization of lemon fruits grown in Himachal Pradesh. Preparation of juice powders also opens a new avenue for the substitution of citric acid in the food industry. Further, the developed technology of cation exchange resin treatment of lemon juice, for reduction of browning and better retention of quality in such products, can be extended to other juices like that of apple, pear, lime etc.

Name of student : Rakesh Sharma (H-99-17-D) Year of completion of degree : 2003 Name of Major Advisor : Dr B B Lal Kaushal Title of the thesis : Extraction and evaluation of oil from different cultivars of olive (Olea europaea L.)

Abstract Suitability of appropriate method for maximizing yield and quality of oil from different

cultivars of olive in Himachal Pradesh was evaluated. Out of various cultivars grown in different parts of the state, Coratino, Leccino and Frantoio with higher recovery of oil have been found suitable for oil extraction purposes, while Cornicobra, Moraiolo, Cipressino and Ballenquata with comparatively lower oil yields can be used for table purposes. The major chemical characteristics consisting of iodine value, saponification value, free fatty acids and peroxide value in olive oil of different cultivars ranged between 72.10 to 83.25, 186.55 to 200.60, 0.48 to 0.85 per cent and 4.95 to 8.30 meg/kg, resp0ectively. Further, various cultivars of olive grown in Chamba (1045 m amsl), Mandi (1300m amsl) and Solan (137m amsl) areas of Himachaql Pradesh did not show any significant difference in both yield and quality of oil. As expected, the lipid profile of extracted oils showed the predominance of oleic acid (67.24-73.70%) followed by palmitic acid (15.83-19.20%), linoleic acid (7.28-9.60%), palmitoleic acid (1.01-1.90%) and stearic acid (0.90-1.80%) besides the presence of traces of linolenic acid and arachidic acid. Broadly, the quality of oil extracted from different cultivars of olive in the state was well within the minimum specifications of olive oil as laid down under Indian Food Laws. Out of different combinations, the method consisting of malaxation of crushed olives for 60 minutes followed by pressing in hydraulic press (15 tonnes m-2) for 30 minutes prior to centrifugation (5000 rpm) for 20 minutes has been found the most appropriate with respect to yield and quality of oil. Further, the use of enzyme combination of Pectinase + Cellulase (1:1) @ 0.05 per cent brought about significant improvement in oil yield both at laboratory and commercial scale. The storage of fresh olives up to 5 days at ambient temperature and up to 10 days in the cold store (5oC) as a waiting period prior to oil extraction did not cause any adverse effect on the yield and quality of extracted oil however, beyond this period both yield and quality of oil was affected adversely. The olive cake left after oil extraction contained appreciable amounts of crude fibres, proteins

and minerals and thus can be used as a source of supplementary animal feed. The storage of olive oils up to six months at ambient temperature did experience some increase in their free fatty acids, saponification value, peroxide value and unsaponifiable matter with corresponding decline in their iodine value and total phenolics, however, these changes were less in the oils packed in coloured glass bottles as compared to those packed in transparent glass bottles. Further, the addition of 0.02% TBHQ to the oil as an antioxidant brought about significant improvement in the quality of stored oil. Further, standardized method of oil extraction using combination of enzymes during malaxation was found quite cost effective over conventional method of oil extraction. Thus, commercial adoption of the standardized technology for oil extraction from recommended cultivars in the state seems to be a profitable proposition.

Name of student : Manisha Kaushal (H-2000-8-D) Year of completion of degree : 2004 Name of Major Advisor : Dr P C Sharma Title of the thesis : Utilization of seabuckthorn (Hippophae sp.) for preparation and evaluation of some value added products.

Abstract The suitability of utilizing berries of sea buckthorn (Hippophae sp.) for the preparation of

various value added products viz., ready-to-serve beverage, appetizer (spiced squash), fruit leather, pulp concentrate (paste) and seed oil was evaluated. Among various combinations, ready-to serve beverage prepared by using 10 per cent pulp and a TSS of 15oB along with 0.02 per cent mixed fruit flavo9ur without any exogenous addition of citric acid was rated the best. Similarly, on the basis of physico-chemical and sensory characteristics, the spiced squash (appetizer) prepared by using 25 per cent pulp and 45oB total soluble solids, in combination with suitable proportion of salt (common and rock salt), ginger mint and spice extract has been found the most appropriate. Further, the high acid content of sea buckthorn pulp was successfully utilized for the preparation of fruit leather by using foam mat drying technique. The addition of potassium metabisulphite @ 600 ppm SO2 to the pulp prior to foaming and drying brought about significant improvement in retention of ascorbic acid, carotenoids and natural colour besides imparting good preservative action. Out of different levels of evaporative concentration viz., 20, 30, 40, 45oB the pulp concentrate (paste) of 40oB has been optimized as evaporation beyond this level caused severe deterioration in colour and other quality attributes. The proximate composition of all the developed products (ready-to-serve drink, appetizer, leather and concentrate) from sea buckthorn pulp contained an appreciable amounts of ascorbic acid (43.26-1045.72 mg%), carotenoids (1.54-44.99 mg%), proteins (164.48-4630.0 mg%) and phenols (0.034-940.60 mg%) besides other bioactive substances. The seeds left after pulp extraction of sea buckthorn berries contained 4.60-5.01 per cent oil which possessed an appreciable amount of oleic (31.8-37.0%), linoleic (25.8-27.9%) and linoleic (14.1-17.8%) acid besides containing a

small proportion of palmitic (C16:0), palmitoleic (C:16.1) and eicosapentaenoic (C20.5 03) acid. The sea buckthorn seed oil exhibited good disinfecting property against E. coli thus, this oil can successfully be exploited in various pharmaceutical preparations. The seed cake left after oil extraction contained a good proportion of crude protein (27.7-33.2%) crude fibre (15.0-21.9%) and total ash (2.7-3.6%) which suggests its utilization in manufacture of various feed supplements. During six months of storage period at ambient temperature (14.6-26.1oC), the sea buckthorn seed oil packed in glass vials did not exhibit any significant changes as its various quality attributes viz., acid value, iodine value, saponification value and peroxide value remained well within the range prescribed under the Chinese National Standards for sea buckthorn seed oil. Similarly, all the processed products from sea buckthorn such as ready-to-serve drink, appetizer, leather and paste indicated a good storage stability upto six months at both ambient (14.6-31.1oC) and low (3-7oC) temperaturs. Further, the use of glass bottles for packing of RTS drink and appetizer, wrapping of fruit leather in butter paper prior to packing in polyethylene pouches and packing of paste in KDPE bottles has been found well suitable as it exhibited better retention of nutrients during storage. Similarly among different combinations, the use of potassium metabisulphite within specified limits under Indian Food Laws in various products has been found the most appropriate in preservation of these products. Thus, utilization of sea buckthorn berries for the most appropriate in preservation of these products. Thus, utilization of sea buckthorn berries for the manufacture of different products seems to be a profitable proposition for popularizing its in cold desert of Indian Himalayas.

Name of the student : Devender Attri (H-99-24-D) Year of completion of degree : 2004 Name of Major Advisor : Dr V K Joshi Title of Thesis : Production and Evaluation of Microbial Colours

Using Apple Pomace Abstract

Colour is the most important attribute of any article especially food. our colour producing microorganisms were isolated from different sources of water, soil, juices and pple pomace. The isolated microorganisms were Rhodotorula (apple pomace), Chromobacter (Soil), Sarcina (bread) and Micrococous (contaminated water). These micorganisms produced pink, dark red, dark yellow and light yellow colour, respectively. The apple polmace was incorporated maximum in medium for Rhodotorula (50g/l) followed by Chromobacter, Macrorococcus (20g/l) and Saricina (10g/l). The optimum incubation temperature of 30oCk, pH 6 and an incubation period of 72 hours were found suitable for the growth of Thodotomla. Optimum incubation temperature for Sarchna includes 35oC temperature, pH 5.5 and 72 hours of incubation period Chromobacter and Micrococcus can be best grown at incubation temperature of 35oC for 48 and 96 hours of incubation period, respectively. The optimum pH for both the organisms was found to be 6.0. Mantose as a carbon source and potassium nitrate as nitrogen source both @ 0.1% was found optimum for the pigment production from Chromohacter sp. Rhodororula produced maximum quantity of pigment at 0.2 % maltose and 0.3 % ferrous

ammonnm sulphate. The highest yield and carotenoids were recorded using 0.1 % glucose and 0.3 % potassium nitrate for the growth of Sarcine sp. Micrococcus utilized 0.1% fructose as carbon source and 0.2 % sodium nitrate as a nitrogen source. The thin layer chromatography showed torulahodin and torulin as major compound in Rhodotorula having maximum absorption at 480 nm. The major compounds found in Sercina were hydrocarbon and dihydroxylated compounds having maximum absorption at 520 nm. The Chromobacter showed maximum absorption at 530 nm whereas Micrococcus showed maximum absorption at 480 nm having canthaxanthin and 4' 4' diketo β carotene as major componds. The maximum water solubility (60%) in Chromobacter using amino-acetic acid, and more effect of temperature at 121oC than at 100 and 60oC for all the four organisms. There were less changes at pH 2 than at pH 6 in all the four organisms. The changes in colour were rapid in forst 15 days than in the later period of storage. The sensory scores were recorded highest at 60oC in dark than in the day light for all the four microorganisms. The changes in colour were rapid in first 15 days than in the later period of storage. The sensory scores were recorded highest at 60oC per gram cost of the microbial pigment was Rs. 9.46 (Micrococcus sp), Rs 7.31 (Chromobacter sp), Rs 5.21 (Sarcina sp) and Rs 3.98 for Rhodotorula sp. so by the apple pomace and with the above optimized conditions microbial pigments can be produced. Use of these pigments in processed food is promising with large economic potential but further research for toxicity of microbial pigments is required.

Name of the student Somesh Sharma (H-2000-9-D) Year of completion of degree 2004 Name of Major Advisor : Dr V K Joshi Title of Thesis Lactic Acid Fermentation of Some Vegetables for

Product development and Bacteriocin Production.

Abstract Carrot, radish and cucumber are the important vegetables grown in India. These can be preserved only for a very short period and thus their availability to the consumers remains seasonal. Among, different methods of preservation, lactic acid fermentation is one of the alternatives for this purpose. Further, increasing consumers awareness for more natural products with no chemical or synthetic preservative has also necessitated the need to exploit the biologically derived antimicrobial substances. The present investigations were carried out with the optimization of the conditions for lactic acid fermentation of vegatables viz., carrot, radish and cucumber to increase their shelf-life with improved flavour, than to test the antimicrobial effect of bacteriocins of lactic acid fermentation on pathogenic or spoilage causing microorganisms, and further development and evaluation of the products from fermented vegatables for nutritional quality and safety aspects as well as evaluation of the economics of the developed products. Carrot, radish and cucumber were procured and LAB fermented to optimize for salt substitution (2%, 2.5% and 3%), temperature (22oC, 26oC and 32oC), type of fermentation (Natural vs Inoculated), use of additives (Mustard, MgSO4 + MnSO4 + MnSO4 and lactose) and salt substitution. For LAB fermentation of carrot (Asiatic type) and radish (Chinese pink), salt concentration 2.5 per cent, mustard 2.0 per cent and temperature 26oC in sequential culture was the best. However, for cucumber (Hybrid 6125) salt concentration of 3.0 per cent, mustard 2.0 per cent, temperature 32oC with sequential culture had produced product with best quality. Similar to those produced by natural fermentation has advantage of controlled fermentation over that of natural. The sensory qualities of salt substituted with KCl or CaCl2 had not produced product with desired sensory quality. Storage of fermented products packed in glass jars and stored under refrigerate condition had higher quality. Bacteriocin from isolate CA44 isolated in natural fermentation was stable upto a heating temperature of 100oC and its activity was completely degraded at 121oC. however, bacteriocin had shown maximum activity at pH 4-5. On basis of phsysico-chemical and sensory characteristics in fermented carrot based products, RTS, prepared from 40 per cent fermented carrot + 60 per cent mango was the best. However, for sauces the blend of 50 per cent fermented carrot + anardana (1:1 ratio) was ranked the best. However, in appetizer, fermented carrot appetizer was rated the best. Further, amongst the radish products RTS drink containing 30 per cent radish + 70 per cent mango, sauce prepared with 25 per cent radish + 75 per cent pear, appetizer containing 20 per cent radish + 10 per cent apricot were ranked the best. The instant chutney prepared with fermented radish + anardana (1:1 ratio) was adjudged as the best. On the basis of physico-chemical and sensory characteristics of various fermented cucumber based products, RTS prepared with 20 per cent fermented cucumber + 80 per cent mango, sauce with blend of 50 per cent cucumber + 50 per cent pear, appetizer

containing 10 per cent fermented cucumber + 20 per cent apricot were the best. The instant chutney prepared with fermented cucumber + anardana (1:1 ratio) was adjudged as the best. The products developed have shown the utility of LAB fermentation in product diversification especially with health implications. The cost of production of fermented vegetables was more for radish than cucumber and carrot. For fermented vegetable based RTS drinks, the lowest cost was recorded for carrot based fermented RTS drinks followed by radish, cucumber based drink. Amongst the appetizer the lowest cost was found for carrot, which was comparable with radish based appetizer. Amongst the cost of instant chutneys, the lowest was found for instant carrot anardana based chutney. The cost of production of radish based fermented vegetable sauce was the lowest. Overall, the investigations have resulted in the development of process for LAB fermentation, new products with better sensory qualities, bacteriocin production as an natural additive for preservation. It has provided a simple technique to preserve the vegetables at comparatively lesser cost and potential for conversion into value added products with healthful properties.

Name of the student : Anju Bala (H-2000-11-D) Year of completion of degree : 2004 Name of Major Advisor : Dr B B Lal Kaushal Title of Thesis : Preparation and evaluation of debittered lime juice

and concentrate

Abstract Lime (Citrus aurantifolia Swingle) is an important and prospective fruit crop of subtropical region. Owing to its many superior characteristics and increasing demand, its production is increasing year per year. But like other citrus fruits the bitterness poses a great hindrance for its utilization for processing into juice of preservation in the form of concentrate commercially. Thus investigations aimed at reduction in the bitterness of the juice and its preservation as juice or concentrate could certainly be useful not only for processing industry but also to the lime fruit growers. The findings clearly reveals that the preserved lime juice can be successfully debittered using adsorbent XAD-16 and the debittered juice can be used for preparing concentrate of 45, 60 and 72oB. All the concentrates packed in glass and HDPE containers with or without SO2 could be stored for 9 months at ambient temperature without any significant changes in quality. The concentrates can be successfully converted into RTS drinks with good consumer acceptability. The technology developed holds promise for commercialization and marketing of the products at economical prices.

Name of the student Dev Raj (H-2000-10-D) Year of completion of degree 2004 Name of Major Advisor : Dr B B Lal Kaushal

Title of Thesis Screening pf potato (Salanum tuberosum L.) cultivars for processing and value addition

Abstract Potato (Solanum tuberosum L.) belonging to family Solanaceae is one of the major tuber crops of the world and most important commercial vegetable vis-a-vis food crop grown in India. At present many countries are giving emphasis on the preparation of different processed products like potato chips. French and commonly occurring problem in the potato processing industry is to maintain the desirable colour and investigations on "Screening of potato (Solanam tuberosum L.). cultivars for processing and value addition" reconditioning, standardization of pre-treatments, selection of suitable frying media along with optimum value added products and their subsequent storage; could be very useful for the potato processing industry in the state and country as well. The encouraging results of the present investigations indicate that potato cltivars viz. Kufri Chipsona-2, Kufri Chipsona-1 and Kufri Chandramukhi may be recommended for processing into chips and French fries even after cold storage followed by reconditioning period of 7, 14 and treatment of slices and sticks with combination of sodium chloride (3.0%) and ascorbic acid (0.05%) can be used to prevent enzymatic browning at laboratory as well as commercial scale, to remarkable extent. The combination of Glucose oxidase + Catalase (1:1) @ 0.01 per cent resulted in reduction of NEB and increase in sensory score in chip, French fries and flour at par with those treated with KMS @ 0.2 per cent. However, enzyme treatment is not a viable alternative to sulfite in controlling NEB because treatment with KMS @ 0.2 per cent may be recommended for prevention of non enzymatic browning during processing. Further chips and French fries should be fries in refined sunflower oil along with 100 ppm of IBHQ to extent their storage life. On the other hand, unmarketable potatoes available in the market during glut season can be utilized more beneficially for preparation of value added products. These value added products like Instant Halwa Powder, Instant Tikki Powder and Istant Custard Powder can successfully be stored for more than 6 months after packing in polythene begs without much changes in physico-chemical, sensory and microbial quality. Thus, the developed technologies can commercially be explored as industry for the production of quality potato chips. French fries, flour, starch as well as value added products. Therefore profitable utilization of potato tubes grown in India for processing can ensure better returns to the growers.

Name of the student : Sandeep Kumar Chauhan (H-2001-18-D) Year of completion of degree : 2005 Name of Major Advisor : Dr K S Thakur Title of Thesis : Storage behaviour of apple cv. Starking Delicious

as affected by pre-and post-harvest treatments of commercial neem based formulations, plant extracts and leaves

Abstract The present studies entitled “Storage behaviour of apple cv. Starking Delicious as affected by pre- and post-harvest treatments of commercial neem based formulations, plant extracts and leaves” were conducted during 2003-2004 and 2004-2005 in the Department of Post Harvest Technology, Dr. Y.S. Parmar University of Horticulture and Forestry, Nauni, Solan-173 230 (H.P.). The whole programme of work was divided into three separate experiments. The experiments pertaining to application of pre-harvest treatments was laid out in a commercial orchard in an important apple growing areas of Himachal Pradesh. Commercial formulations of neem based products viz., Nimbecidine, Neem Azal and Neem Gold were applied at different concentrations to individual trees 20-25 days before the expected date of harvest. In the second experiment, coating materials, prepared from extracts of various plant leaves viz., Neem, Drake, Spearmint and Marigold were applied to fruits in two different concentrations immediately after harvest. Whereas in the third experiment, fresh leaves of plants known to possess antimicrobial properties were collected and used as cushioning material for fruits packed in CFB cartons of 3.5 kg capacity. Fruits from all the experiments were stored at 1+1oC and 85-90 per cent relative humidity and physico-chemical analysis of fruit were done at monthly intervals during the 180 days storage period. Among pre-harvest treatments of commercial neem based formulations, 1.5 per cent Nimbecidine proved to be an efficient treatment in reducing physiological loss in weight, spoilage and this treatment also enabled the fruit to retain maximum fruit firmness, juice yield and overall acceptability, whereas, 2.0 per cent Neem Azal proved to be highly effective in retaining most of the biochemical constituents viz., TSS, acidity, starch and pectin contents. These treatments were also effective in reducing the rate of respiratory and enzymatic activity as a result of which the fruits exhibited higher mean values for these parameters. Among extracts of plant leaves used for coating of fruits, 20 per cent neem leaf extract was most effective in minimizing losses in PLW, firmness, juice yield, acidity, starch, pectin thereby having maximum overall acceptability. In the experiment pertaining to the use of fresh leaves as cushioning material, Camphor leaves exhibited consistent superiority over the other treatments in retaining most of the physico-chemical characteristics of fruits during storage. However, treatments with Drake and Spearmint were most effective in reducing fruit spoilage during storage.

Name of the student Alkesh (H-2001-17-D) Year of completion of degree 2005 Name of Major Advisor : Dr V S Barwal Title of Thesis Production of carotenoids as food colourants from

natural sources

Abstract Colours are vital constituents of food. Colour is the first characteristics perceived by the

senses and helps in determining acceptability, judging quality and increase basic aesthetic value of food. Increasing consumer awareness for natural products with no chemical additives and certified dyes has necessitated the need to exploit food colourants of natural origin. Present

investigation was carried out to produce carotenoids pigment as natural food colourants. Three natural sources viz., citrus peel, carrot and paprika were taken for studies and were treated with 0.2 per cent KMS for 5 min and dried at 45+5oC in a mechanical dehydrator. The caroteniods were extracted from dehydrated samples by method 2 in citrus peel and carrot while in paprika by method 1. Carotenoids (crude pigments) were harvested with dextrin white as carrier material. Harvested carotenoids pigments were treated with different antioxidants like BHT, TBHQ, KMS and ascorbic acid and were packed in transparent as well as in amber glass vials for storage studies of 3 months at ambient and refrigerated temperature. Among the antioxidants used butylated hydroxytoluene (BHT) was reported best followed by potassium metabisulphite (KMS). Maximum carotenoids content and tintometer reading (yellow and red units) were observed in crude pigments packed in amber glass vials kept at refrigerated conditions as compared to transparent glass vials stored at room temperature. Crude carotenoids pigments of citrus peel, carrot and paprika had maximum observance at 400 nm, 420nm and 450 nm wavelength in acetone, respectively. TLC of carrot and paprika in the solvent system of petroleum ether showed the presence of β-carotene. HPLC analysis of crude caroteniods pigments revealed the presence of β carotene in citrus peel (1.72%), carrot (96.00%) and paprika (11.75%). Stability of crude carotenoids pigments in ready-to-serve (RTS) drink and squash (model and lemon) was studied upto 9 months storage. Lemon based ready-to-serve (RTS) drink and squash had better stability, higher sensory score of these carotenoids pigments as compared to model system. Crude carotenoids pigment produced from citrus peel, carrot and paprika cost to Rs. 180.78, Rs. 209.69 and Rs. 125.88 per gram, respectively.

Name of the student B.M.K.S. Tilakardane Year of completion of degree 2007 Name of Major Advisor : Dr P C Sharma Title of Thesis Studies on Utilization of kernel oil and press cake of apricot for value addition

Abstract The suitability of utilization of apricot kernel oil and press cake for preparation of

different value added products such as facial cream, lip balm, essential oil and protein isolate was evaluated. The sweet and bitter apricot kernels contained 46.9-47.6% oil. The bitter apricot kernels were found to contain I62mg HCN /I00g which is known to be produced from the hydrolysis of inherent amygdalin in the kernels. For removal of HCN. the blanching of kernels in boiling water for 20 minutes was found most appropriate and kernels were found suitable for oil extraction. Further, the quality characteristics of the oil with light to deep yellow colour. 1.4711 to 1.4729 refractive index, 2.29mg KOH /g acid value; 4.3-5.28 meq/kg peroxide value; 100.3-110 4g I2/I00g iodine value and saponification value 190.3-193.6 mg KOH/g and 0.7-0.8 % unsafonifiablc matter was found similar to almond oil as specified under Indian Food Laws. The oil also contained 430-438ug/g vitamin F. which is regarded as natural antioxidant and make the oil suitable for cosmetic and pharmaceutical purposes. The apricot kernel oil is rich in unsaturated fatty acids containing oleic (62.07%) and linoleic (27.76%) as the major fatty acid portion, while saturates accounted for only 8.72%. The optimized method for preparation of facial cream consisted of mixing apricot oil and water (1:1) along with other ingredients such as

bees wax. sodium alginate, stearic acid, titanium dioxide, borax powder. TBHQ and jasmine oil in appropriate proportion followed by blending to yield desired emulsion of a cream. While lip balm is prepared by mixing apricot oil, bees wax. honey and mint essential oil and blended lo obtain fine paste The facial cream prepared from apricot kernel oil owing to the presence of vitamin E and linoleic acid was found to impart good moisture retention and anti-ageing properties to the skin uhcreas lip balm helped to check cracking of lips. Both the products stored well up to six months at ambient temperature without an) significant change its physico- chemical and sensory attributes The kernel oil packed in amber coloured glass bottles, amber coloured PET bottles and l.DPF pouches after addition of antioxidant TBHQ (0.02%) remained stable up to six month at low temperature (3-7 °C). Apricot oil can also be blended with coconut oil in 15:85 ratios and with almond oil in 10:90 ratios without affecting their original chemical and sensory' attributes. Die press cake left after oil extraction was utilized for the preparation of essential oil for use as a llavouranl and for extraction of protein isolate. For extraction of essential oil, the method consisting of maceration of press cake in water (1:10) slurry at 50 C for I hr followed by distillation and redistillation of distillate in CaO and FcfiQi was found the most appropriate. The essential oil obtained from press cake (0.97%) contained 89.0% bcnzaldchyde. which can be utilized for preparation of flavoured sweetened milk at the concentration of 0.5%. Besides, the essential oil has good antimicrobial property against Staphylococcus aureus and Escherichia coli and as such can be used in both cosmetic & pharmaceutical preparations. The apricot oil and facial cream however showed anti microbial activity only against E. coli. The method for preparation of protein isolate consisting of boiling slurry (press cake in water 1:20 proportion) for 01 hr and maintaining pH of slurry to 8.0 followed by filtration and acidification filtrate to pH 4.0 for coagulation of protein has been found the most appropriate The press cake contained about 23 4% protein isolate which was found to have 68.8% crude protein with water and oil absorption capacity of 1.4 and l.38g/g respectively. Thus, the apricot kernel oil can successfully be utilized for preparation of facial cream and lip balm with good cosmetic properties and for blending with coconut and almond oil with improved nutritional qualities while, press cake can be used for preparation of essential oil as apricot llavorant and protein isolate for protein fortification purposes.

Name of the student L. Sophia Devi Year of completion of degree 2007 Name of Major Advisor : Dr S P S Guleria Title of Thesis Studies on shelf-life extension of peach [Prunus persica (L.) Batsch] cv. July Elberta"

Abstract

The present studies entitled "Studies on shelf-life extension of peach [Prunus persica (L.) Batsch] cv. July Elberta" were conducted during 2006 and 2007 in the Department of Post Harvest Technology College of Horticulture, Dr Yashwant Singh Parmar University of Horticulture and Forestry, Nauni, Solan - 173230 (H.P.). The whole programme of work was divided into three separate experiments. The experiment pertaining to application of pre-harvesl treatments was laid out in a commercial orchard in Rajgarh areas of Himachal Pradesh. Among pre harvest treatments, 1.0 per cent calcium chloride proved to be an efficient treatment in

reducing physiological weight loss, spoilage and this treatment also enabled the fruit to retain maximum fruit firmness, acidity, ascorbic acid, pectin content and overall acceptability, however, these treatments were also effective in reducing the rate of respiratory and enzymatic activity as a result of which the fruits exhibited higher mean values for these parameters. Moreover, among post harvest edible coating treatments so adopted, 30 per cent neem leaf extract was most effective in minimizing physiological weight loss, firmness, acidity, pectin; and thereby, exhibiting maximum overall acceptability. In the experiment pertaining to the use of different packaging material combined with postharvest coating, 1 per cent garlic extract combined with tray packed shrink wrapping exhibited consistent superiority over the LDPE packed fruits in retaining most of the physico-chemical characteristics of fruits during storage.

At the same time, precooling of the produce at field level in combination with the most

effective preharvest treatment as well as post harvest surface coating along with tray packed shrink wrapping of the produce helped in retaining most of the physico-chemical characteristics as well as organoleptic consumer preference traits and quality characteristics to the maximum extent vis-a-vis fruits those were not subjected to precooling but were otherwise tray packed shrink wrapped in the control treatments. In utter contrast to the results of various pre harvest treatments and postharvest coatings which were beneficial in providing longevity to the freshly harvested peach fruits for maximum of 32 days, the innovative low pressure containers provided extension of storageability to peach fruits for 2 months under cold storage conditions with only negligible spoilage, and that the developed LPS is versatile as it can be used as a precooling device to remove field heat at field level because the system is portable and easy to operate even by a layman.

Name of the student R.M.N.A. Wijewardane Year of completion of degree 2008 Name of Major Advisor : Dr S P S Guleria Title of Thesis Natural extracts for shelf life extension of apple cv. Royal Delicious (Malus domestica)

Abstract

The present investigations entitled. "Natural extracts for shelf life extension of apple cv. Royal Delicious (Malus domestica)" have been conducted in the Department of Post Harvest Technology, College of Horticulture. Dr Yashwant Singh Parmar University of Horticulture and Forestry, Nauni. Solan (Himachal Pradesh), during the year 2006 and 2007. The preliminary experimentation suggested the use of 2 per cent starch. 1-2 per cent neem kernel oil and 10-20% marigold extract as an optimum dose for adoption and surface coating treatment of fruit for achieving a desired post honest life for the freshly harvested commodity. However, active principles, responsible for post harvest life extension of the produce, consequent upon application of neem oil and marigold extract have been duly analyzed and reported; and. also, the rot causing microorganism during storage intervals has also been identified to be penicillium expansion. Nevertheless, during ambient storage, potato starch alongvvith apricot oil application fairly reduced physiological weight loss; and. as such, effectively managed to retain all other physio-chemical characteristics except fruit softening and galacturonasc activity which was,

however, better reduced by com starch coupled with apricot kernel oil treatment; and that the IrcaUnent compromising of potato starch and neem oil prov ided better sensorial score rating than the controls. Nonetheless, during cold storage experimentation, the potato starch-apricot kernel oil treatment excelled in retaining all the physio-chemical attributes of the commodity, retarding physiological weight loss; and. thereby, also exhibiting better sensorial characteristics except significantly lesser effect on reduction in diseases control mechanisms; which, was. otherwise exercised better by rice starch plus neem oil treatment. Moreover, as far as the effect of precooling and packaging on the commodity is concerned, it has been found that the neem oil surface coating with shrink wrapped tray packing treatment alongvvith prccooling was most effective in providing belter physico-iiieinital umbrella. eff..>..ivelv lowering fruit Softening and enzyme activity, retaining excellent sensorial trails, providing heller consumer preference; and. in addition, significantly lowering disease incidence. Similarly, the neem oil surface application alonguith shrink wrapped trav packing and coupled with prccooling treatment during cold storage related better in retention of storage life than the ambient storage; and. whereas, the treatment effect on physico-chemical characteristics of commodity, lowering in incidence of fruit softening and spoilage: and. as well as, consumer preference was belter lhan the effect of the same treatment during ambient storage, and. however, the treatment effect was statistical! v at par with the marigold extract application with shrink wrapped tray packing alongwith precooling exercises during cold storage experimentation.

At the same lime, the innovative low pressure containers provided extension of storageability to apple fruits for 4 months under cold storage conditioas with only negligible spoilage: and with the best control over physio-biochemical traits over and above all other treatments: and that the developed LPS is versatile as it can be used as a precooling device to remove lield heat at field level because the system is portable and easy to operate even by a layman Moreover, the cost effectiveness of the botanical extracts so employed to that of LPS system so adopted for experimentation have also been worked out.