alternative food preservation tech

7/30/2019 Alternative Food Preservation Tech

1/40


2/40

Occasionally described as non-thermal.

As consumers increasingly perceive freshfood as healthier than heat treated food,the industry is now seeking alternativetechnologies to maintain most of the

fresh attributes, safety and storagestability of food.


3/40

Inherent disadvantages of thermalprocessing

Loss of original flavor, taste, appearance,color.Nutritional quality.Nutraceutical value.


4/40

Objectives: Render foods free of pathogenic &

spoilage organisms Retain color, flavor Improve shelf life Improve texture

Non-Thermal Processing


5/40

Non-thermal Processing

Techniques. High Pressure Processing. (HPP) Pulsed Electric Field (PEF)

Ultrasound Pulsed Light (PL) Irradiation

Electron Beam Ozone Gas, plasma


6/40

HIGH PRESSURE PROCESSING [HPP]

Application of High Pressure for processing of

foods

Thermal processing Impairing effects on thefresh like qualities of food

Least effect on organoleptic &Nutritional quality

Pressure : 100 1000 MPa


7/40

Effects of High PressureFor orange juice processed at 483 MPa, 60s, 7 log reduction of pathogens (E. coli,Salmonella).

HHP treated OJ was very close to freshlysqueezedFor RTE meats, processed at 600 MPa, 3-4log reduction ofL. monocytogenes.

HHP acts instantaneously and uniformlythroughout a mass of food independent ofsize, shape and food composition.


8/40

EFFECTS ON MICRO ORGANISMS!!!!!!!!

Extent of inactivation Depends on

Type of micro organism Pressure level

Process time

Temperature

Induce changes in

Morphology

Genetic mechanism

Cell membranes


9/40

EFFECT ON FOOD COMPONENTS Change in native structure of protein changes the

functional properties

Pressure of 400

500 MPa leads to denaturation, gel

formation, coagulation and aggregation of protein

Starch : Gelatinisation and modification for enzymatic

hydrolysis


10/40

COMPONENTS OF HIGH PRESSURE SYSTEM

Pressure container Monolithic structure, Low alloy Steel

pressure vessel

Pressure generator- Special type of hydraulic pump,

Pressure intensifier

Decompression system Valve mechanism

Hydraulic fluid - Water, Ethanol + castor oil (80 & 20 %)


11/40

PROTOTYPE OF HIGH PRESSURE SYSTEM


12/40

APPLICATION IN FOOD INDUSTRIES

FOODS PRESSURE

(MPa)

TIME

(Min)

Fruit Juices (Grape, Mandarin,Citrus,Strawberry)

400 - 500 5 -15

Jams (Apple,Kiwi fruit strawberry) 400 10 - 30

Pears 500 15

Strawberry puree 400 20

Apple and Strawberry desserts 400 15

Sweet potato 400 10

Soya bean,Rice, Potato 450 5 20

Milk 370-680 10-80

Cream (40%) 700 10

Ground chicken 310 10


13/40

ADVANTAGES OF HPP.

Elimination of chemical preservatives.

Reduced processing time & Energy requirement.

Retention of freshness, flavour, colour and

texture.

Vitamins are retained


14/40

DISADVANTAGES ..Enzymes requires high Pressure for inactivation.

Require low temp storage and distribution.

High capital investment


15/40


16/40


17/40


18/40


19/40

High Intensity Pulsed Electric Field (PEF)

Processing

Applications of high voltage pulses to foods

placed between two electrodes.

10 to 80 kV/cm10 to 10000 s


20/40


21/40

Application of short burst of highvoltage to a food placed between twoelectrodes

PEF destroys the microorganisms byelectroporation i.e. increasing thepermeability of the cell membrane


22/40

Microbial inactivation depends on

Electric field strength

Treatment time

Treatment temperature

No of pulses


23/40

Examples of PEF Processed Foods

Apple juice Orange juice

Milk Beaten eggsGreen pea soupBrine solution


24/40

Advantages of PEFProcessing

Temperature rise is very less. Cold Sterilization.No effect on heat sensitivematerials.Inactivates enzymes.


25/40

IRRADIATION

Exposing food material to ionizing

radiation.

Also know as Cold sterilization technique

Gamma rays, accelerated electrons-Dislodge electrons, thus ionize food

materials.

The permitted dose level for the foodapplication is below 10kGy.


26/40

DNA molecules are broken either by the direct deposition of

radiant energy and/or by active radical such as OH, H, H2O2

etc.

Microorganisms and insect pests are killed by direct and

indirect effect.

The ions caused by such radiation can affect the normal

biological processes

Effect of Irradiation..


27/40

Food products Purpose Dose(kGy)

Date ofClearance

White potato Extend shelf life .05-.15 1965 Nov

Spices and dry seasoning Disinfect insect 30 1983 Jul

Fresh fruits Delay maturation 1 1996 Apr

Poultry (fresh or frozen) Control illness 3 1990 Dec

Red meat Decontamination 3 1997 Dec

Potato Inhibit sprouting 0.15 1960 Nov

Onions Sprouting inhibition 0.15 1965 Mar

Wheat, flour,wheat flour Disinfestations 0.75 1969 Mar

Poultry meat Decontamination 1.5-3 1992 Sep

Red meat(fresh) Decontamination 4.5 1997 Feb

Cereals 1

Bulbs and tubers 0.2

Herbs Decontamination 10 1984 Oct

Condiments 10

FOODS APPROVED FOR IRRADIATION


28/40

Commercially Important Applications

1. Insect disinfestations of stored products

2. Quarantine treatment for fruits and vegetables

3. Inhibition of sprouting in tuber and bulb crops

4. Delay in ripening of fruits.

5. Extended shelf life of seafood, meat and meat products.

6. Improving food safety and decontamination of spices and

sterilization of foods.


29/40

Current Food Products Processed byIonizing Radiation.Potatoes,Spices,Dry vegetable seasoning,Ground beef, pork, poultry,Some fruits and vegetables.

Food irradiation is one of the most extensively and

thoroughly studied methods of food preservationThakur and Singh (1994)


30/40


31/40

Consumer Acceptance

The greatest disadvantage of food irradiation is its

nameevokes unpleasant associations of

radioactivity,nuclear threats, high technology, genetic

mutation, and cancer


32/40

Ozone Processing

Ozone (O3) A gas - triatomic form of oxygen.

Most powerful oxidizing agent available forconventional water treatment highly reactive. Unstable - must be generated onsiteand used. Slightly soluble in water, but more so

than oxygen.


33/40


34/40


35/40


36/40

Power Ultrasound Processing

Pic


37/40


38/40

High Intensity Pulsed Light Processing

Intense, short duration, broad-spectrum light isexposed to a food or package

Very effective on product surfaces Marginally effective at penetrating to depths infoods Reduces the need for chemical disinfectants and

preservatives


39/40

Pulsed Light Processing Treatment of packaged products by pulsed lightminimizes risk of further recontamination. Many plastics can be used to efficiently

transmit light tothe product. Ex.: polyethylene, polypropylene,nylon


40/40

THANKING YOU

alternative food preservation tech

Documents