The document discusses emerging food processing technologies that can help reduce post-harvest losses of fruits and vegetables in India. It provides an overview of technologies like ohmic heating, microwave heating, pulsed electric field, high pressure processing, ultrasound, and pulsed light and explains their principles, components, applications, advantages, and limitations. These emerging technologies can help maintain the quality and safety of foods while being more energy efficient alternatives to conventional thermal processing methods.
1. EMERGING TECHNOLOGIES IN FOOD
PROCESSING
Presented by:
Sheshrao Kautkar
Dept. of Post Harvest Process & Food Engg.
G. B. Pant University of Agril. & Tech., Pantnagar (U. K.)
2. INTRODUCTION
2
Fruits & Vegetables – Perishable commodity
Sensitive to various microorganisms ,temperature, atmospheric gases ,
mechanical handling etc.
Leads to huge mount of post harvest losses.
• 52% cultivable land
compared to 11%
world average
• All 15 major climates
in the world exist in
India
• 46 out of 60 soil types
exist in India
• 20 Agri-climatic
regions
India’s diverse agro-climatic conditions allows production of many fruits
and vegetables.
3. Area and Production of Major Fruits and Vegetables in India:
3
Fruit
Area
(000 ha)
Production
(000 t)
Mango 2516 18431
Citrus 1078 11147
Banana 803 29725
Apple 313 2498
Guava 268 3668
Sapota 177 1744
Papaya 133 5639
Pomegranate 131 1346
Grapes 119 2585
Pineapple 110 1737
Litchi 84 585
Total 7216 88977
Vegetable
Area
(000 ha)
Production
(000 t)
Potato 1973 41555
Onion 1204 19402
Tomato 882 18736
Brinjal 711 13558
Okra 533 6346
Cauliflower 434 8573
Peas 434 3869
Cabbage 400 9039
Tapioca 228 8139
Sweet Potato 106 1088
Total 9396 162897
Fruits Vegetables
4. Post - Harvest Losses of Agricultural Produce
4
Agricultural Commodity Post Harvest Loss (%)
Milk 0.8
Meat 2.3
Fisheries (Marine) 2.9
Poultry 3.7
Cereals 3.9 - 6.0
Pulses 4.3 - 6.1
Oilseeds 2.8 -10.1
Fisheries (Inland) 6.9
Fruits and Vegetables 5.8 -18.0
Source: Nanda SK, et al, CIPHET Ludhiana
6. Need of Food Processing, Preservation and Value Addition
To increase the shelf life commodity
Reduction of post harvest losses
Maintain quality and stability of product
Maintain food and nutritional security of the country
Availability of variety of products
Availability throughout the year
Availability throughout the country
Employment generation
Minimization and utilization of waste
6
7. Processing Methods
7
Ohmic heating
Infrared heating
Microwave heating
Radio frequency heating
Freezing
Drying
Frying
Chilling
Extrusion
Blanching
HPP
PEF
Pulse light
Ultrasound
Irradiation
Ozonation
Cold plasma
Electron beam
Oscillating magnetic
field
Thermal
Non thermal
8. Problems in Conventional Methods
8
Thermal damage
Nutritional loss
Energy inefficient
Emission of
combustion gases
Longer
processing time
9. Emerging Food Processing Technologies
9
Ohmic Heating, Microwave Heating, Pulsed Electric Field, Pulsed Light
Technology, High Pressure Processing, Ultrasound.
Maintains nutritional quality of the produce by processing at mild
temperatures
Energy efficient processes
Do not emits combustion gases in the atmosphere
Shorter processing time
Automatic control
Higher heat transfer efficiency
Uniform heating
10. Ohmic Heating
10
Advanced thermal processing method
Developed by United Kingdom Electricity Research and Development Center
Licensed to APV Baker Ltd for commercial exploitation
Also called electrical resistance heating, Joule heating, or electro-heating
Green technology.
Food material is heated by passing electric current through it
Electrical resistance of the food causes the power to be translated directly into heat
Electrical energy is dissipated into heat, which results in rapid and uniform heating
11. Components and Applications of Ohmic Heating
11
4. Measuring
systems
1. Two
stainless steel
electrodes
3. Power
supply
System
2. Ohmic
heating
chamber
OH
Components
Applications:
Rice bran stabilization, blanching, sterilization, juice extraction, oil extraction
pasteurization, evaporation, dehydration, fermentation, peeling, thawing etc
12. Advantages and Limitations of Ohmic Heating
12
Advantages Limitations
1. High energy efficiency because 90% of the
electrical energy is converted into
2. Reducing risks of fouling on heat transfer
surface and burning of the food product.
3. Higher temperature that required for HTST
processes can be achieved.
4. Suitable for batch as well as continuous
operation
5. Uniform heating of particulate food with faster
heating rates.
6. Keep product quality basically intact
7. Easy to operate and no residual heat transfer
after the current is shut off.
8. Environmentally-friendly system.
9. Ease of process control with instant switch-on
and shut-down.
1. Only suitable for liquids or particles in
liquids
2. Lack of generalized information
3. Requested adjustment according to the
conductivity of the dairy liquid
4. Narrow frequency band
13. Microwave Heating
13
Principle of MW heating:
It uses electromagnetic waves of frequencies in microwave range (3MHz to 300GHz)
Polar water molecules will rotate according to the alternating electromagnetic field
The water molecule is a “dipole”
“Dipoles” will orient themselves when they are subject to electromagnetic field
Rotate at about 24 billion times per second
Ionic compounds in food can also be accelerated by the electromagnetic field
This orientation of water molecule causes huge friction inside the product and hence
generation of heat take place inside the product.
14. Components and Applications of Microwave Heating
14
Components
Applications:
Pasteurization, sterilization, dehydration, tempering, blanching, baking, cooking,
thawing, boiling etc.
4. Turntable,
Fan & Stirrer
1. Magnetron
3. Cavity
2. Wave
Guide
MWH
15. Advantages and Limitations of Microwave Heating
15
Advantages Limitations
1. Rapid and uniform heating
2. High heating efficiency (80% or higher
efficiency can be achieved);
3. Reduce energy and time of processing
4. Reduced loss of nutrients than conventional
heating
5. Minimum fouling depositions, because of the
elimination of the hot heat transfer surfaces
6. Suitable for heat-sensitive, high-viscous, and
multiphase fluids
7. Does not generate exhaust gas therefore no
contamination of foods by products of
combustion
8. Equipment is small, compact, clean in
operation
9. Surface of the food does not overheat
10. Automatic process control
1. Low penetration depth
2. High initial cost
3. Non uniform heating when using large
size product
4. Less energy efficient than ohmic heating
16. Pulsed Electric Field
16
Principle of PEF:
Also called as High Intensity Pulsed Electric Field
Mainly used to inactivate the deteriorative microorganisms
Pulses of high voltage (20– 80 kV/cm) passed over the product placed between a pair of
electrodes for an extremely short period of time (1–100 µs)
Resistance heating, electrolysis and disruption of cell membranes (electroporation) can
occur contributing to the inactivation of microorganisms.
The gap between two electrodes is called as the treatment gap
17. Components and Applications of Pulsed Electric Field
17
Components
Applications:
Used for preservation of pumpable fluid or semi-fluid foods
Pasteurisation of fruit juices, soups, liquid egg and milk, thawing, decontamination
of heat sensitive foods.
4. Treatment
chamber
1. High-voltage
power supply
3. Discharge
switch
2. Capacitor
PEF
18. Advantages and Limitations of Pulsed Electric Field
18
Advantages Limitations
1. Kills vegetative cells
2. Colours, flavours and nutrients are
preserved
3. No evidence of toxicity
4. Relatively short treatment time
1. No effect on enzymes and spores
2. Only suitable for liquids or particles in
liquids
3. Only effective in combination with heat
4. Energy efficiency not yet certain
5. Regulatory issues remain to be resolved
6. May be problems with scaling-up
process
19. High Pressure Processing
19
Principle of HPP:
Also called as High Hydrostatic Pressure Processing
High pressures, up to 1000 MPa (Mainly 400-600 MPa) are applied to food packages
submerged in a liquid
High pressures, up to 1000 MPa are applied to food packages submerged in a liquid
Pressure causes destruction of micro-organisms
Bacteria in the log phase of growth are more barosensitive than cells in the stationary,
dormant or death phases.
High pressure is applied in an “isostatic” manner such that all regions of food
experience a uniform pressure
20. Components and Applications of High Pressure Processing
20
Components
Applications:
Pasteurization and sterilization of fruits and fruit products, sauces, pickles, yoghurt, meat
and vegetables.
Sterilization of heat sensitive ingredients like shellfish, flavourings, and vitamins.
4.Temp
controller &
handling
system
1. Pressure
vessel,
3. Pressure
generating
device
2. Closure
HPP
21. Advantages and Limitations of Pulsed Electric Field
21
Advantages Limitations
1. Kills vegetative bacteria (and spores
at higher temperatures)
2. No evidence of toxicity
3. Preserve nutritional quality of food
4. Reduced processing times
5. Uniformity of treatment throughout
food
6. Desirable texture changes possible
7. In-package processing possible
8. Potential for reduction or elimination
of chemical preservatives
9. Positive consumer appeal
1. Little effect on food enzyme activity
2. Some microbial survival
3. Expensive equipment
4. Foods should have approx. 40% free
water for anti-microbial effect
5. Batch processing
6. Limited packaging options
22. Pulsed Light Technology
22
Principle of PLT:
Also called as High Intensity Light
Contains a broad spectrum of ‘white’ light, from UV wavelengths of 200 nm to NIR
wavelengths of 1000 nm
Peak emissions between 400–500 nm
Emit 1-20 flashes per second of electromagnetic energy.
The antimicrobial effects of UV wavelengths are due to absorption of the energy by
highly conjugated double carbon bonds in proteins and nucleic acids.
Which attributed to structural changes in the DNA, as well as abnormal ion flow,
increased cell membrane permeability and depolarization of the cell membrane.
decontamination or sterilization technology
23. Components and Applications of Pulsed Light Technology
23
Components
Applications:
Used in decontamination of vegetables, dairy products, baked products, fresh fruit, meats,
seafood and vegetables,
Microbial inactivation of water, and sanitation of packaging materials and disinfection of
equipment surfaces
4.Power
Supply
1. Flash
Lamp Filled
with Inert
gas
3. Pulse
Generator
2. Sample
Shelf
PLT
24. Advantages and Limitations of Pulsed Light Technology
24
Advantages Limitations
1. Medium cost
2. Very rapid process
3. Little or no changes to foods
4. Low energy input
5. Suitable for dry foods
1. Only surface effects and difficult
to use with complex surfaces
2. Not proven effective against
spores
3. Possible resistance in some
microorganisms
4. Reliability of equipment to be
established
5. Lower penetration depth
25. Ultrasound
25
Principle of Ultrasound:
Also called as Ultrasonication
Sound is vibration that transmitted in a medium (air), and can hear by human ear.
The frequency of sound waves audible to human ear ranges from 20Hz to 20 kHz
Frequencies <20 Hz are “Infrasounds” and Frequencies >20 kHz are “Ultrasounds”,
When ultrasound waves meet a medium, it creates regions of alternating compression and
expansion
These compression and expansion cause cavitations i.e. formation of bubbles in the medium
These bubbles are larger in size during the expansion cycle, which increases gas diffusion,
causing the bubble to expand
When the ultrasonic energy is insufficient to retain the vapour phase in the bubbles then rapid
condensation occurs
The condensed molecules collide and create shock waves which create regions of high
temperature and pressure.
26. 26
Types of Ultrasound:
• Frequencies >100 kHz, low power and low-
intensity (<1 W/cm²).
• Non-destructive, Provide information such as
physicochemical properties of food
Low energy
ultrasounds
• Frequencies 18-100 kHz, high power, high-
intensity (>1 W/cm²)
• Used for physical disruption and acceleration
of chemical reactions
High energy
ultrasounds
27. Components and Applications of Ultrasound
27
Components
Applications:
Crystallization, foams destruction, tenderization of meat, extraction, degassing, filtration,
drying, freezing, mixing, homogenization, effluent treatment, growth modification of living
cells, alteration of enzyme activity, sterilization of equipments.
4.Material
Chamber
1. Power
Generator
3. Reactor
2.
Transducer
US
28. Advantages and Limitations of Pulsed Light Technology
28
Advantages Limitations
1. Effective against vegetative cells,
spores and enzymes.
2. Reduction of process times and
temperatures.
3. Little adaptation required of
existing processing plant.
4. Heat transfer increased.
5. Possible modification of food
structure and texture.
6. Batch or continuous operation
1. Complex mode of action.
2. Depth of penetration affected by
solids and air in product.
3. Possible damage by free radicals.
4. Sometimes need to be used in
combination with another process
(e.g. heating).
5. Potential problems with scaling-
up plant
29. CONCLUSION
29
Conventional Processing Methods:
Cause thermal degradation of food
loss of volatile compounds, nutrients, colour, texture and flavour.
Longer processing time, Higher fuel and energy required, combustion gasses.
may generate environmental pollution.
Emerging Food Processing Technologies:
Produce food with better quality, acceptance and shelf life
Reduce the problems of environmental pollution
Higher heating rates and energy efficient processes
Mainly used in the large scale production.
After minimising the investment costs it can also be employed in small scale industries
Commercial adaptation is necessary