new Technology in food processing.

1. New-Emerging Technologies
in food processing
B.Lakshmaiah
Scholar
Dairy microbiology
NDRI

2. What is Food processing?
 Food processing is the transformation of raw
ingredients, by physical or chemical means into
food, or of food into other forms .
 Food processing combines raw food ingredient
to produce marketable food products that can
be easily prepared and served by the consumer.

3. Need of Food processing:
• 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

4. Ohmic heating
Infrared heating
Microwave heating
sterilization
Drying
Frying
pasteurization
Extrusion
Blanching
HPP
PEF
Pulse light
Ultrasound
Irradiation
Ozonation
Cold plasma
Electron beam
Oscillating magnetic field
Thermal
Non thermal
Processing Methods

5. Thermal damage
Nutritional loss
Energy inefficient
Emission of
combustion gases
Longer
processing time
Problems in conventional method :

6. Emerging Food Processing Technologies
• 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

7. Ohmic heating
• 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

8. Components and applications of Ohmic heating
• Application:
• Rice bran stabilization ,blanching, sterilization,juice extraction, oil
extraction,pasteurization,evaporation, dehydration ,fermentation etc…..
1. Two stainless
steel electrodes
2. Ohmic heating
chamber
4. Measuring
systems
3. Power supply
system
OH

9. Advantages and Limitation of Ohmic heating
Advantages
• High energy efficiency because 90%
of electrical energy is converted
• reducing risks of fouling on heat
transfer surface and burning of food
• Higher temperature that required
for HTST process can be achieved.
• Uniform heating of particulate food
with faster heating rates
• Environmentally –friendly system.
Limitations
• Only suitable for liquids or particles
in liquids
• Lack of generalized information
• Requested adjustment according
to the conductivity of the dairy
liquid
• Narrow frequency band

10. Microwave Heating
• Principles :
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` Dipolar’
Dipoles will orient themselves when they are subjected to electromagnetic
field
Rotate at about 24 billion times per seconds
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.

11. Components & applications of Microwave Heating
• Applications: Pasteurization, sterilizations, dehydrations, Tempering,
blanching, baking, cooking, thawing, boiling etc…
Turntable ,
Fan &
stirrer
Magnetron
Cavity
Wave
Guide

12. Advantages and Limitations of Microwave Heating
Advantages
• Rapid and uniform heating
• High heating efficiency ( 80% or higher
efficiency can be achieved)
• Reduce energy and time of processing
• Reduced loss of nutrients than
conventional heating
• Equipment is small compact clean in
operation
• Surface of the food does not overheat
• Automatic process control
• Does not generate exhaust gas
therefore no contamination of foods by
products of combustion .
Limitations
• Low penetration depth
• High initial cost
• Non uniform heating when using large
size product
• Less energy efficient than Ohmic
heating

13. Pulsed Electric Field
• Principle:
 Also called as High Intensity Pulsed Electrical Field
Mainly Used to inactivated 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 micro seconds )
Resistance heating ,electrolysis and disruption of cell membranes
(electroporation)can occur contribution to the in activation of
microorganisms
The gap between two electrodes is called as the treatment gap.

14. Components & Applications of Pulsed Electric Field
• Applications:
• Use 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

15. Advantages and Limitations of Pulsed Electric Field
Advantages
• Kills vegetative cells
• Colours, flavours, and nutrients
are preserved
• No evidence of toxicity
• Relatively short treatment time
Limitations
• No effect on enzymes and
spores
• Only suitable for liquids
• Only effective in combination
with heat
• Energy efficiency not yet certain
• May be problem with scaling-up
process

16. High Pressure Processing
• Principle of HPP:
• Also called as High Hydrostatic Pressure processing
• High pressure up to 1000 Mpa (Mainly 400-600 Mpa) are applied to
food packages submerged in a liquid
• Pressure causes destruction of micro-organisms
• Bacteria in the log phase of growth are barosensitive than cells in the
stationary, dormant or death phases.
• High pressure is applied in an “isostatic” manner such that all region
of food experience a uniform pressure

17. Components & applications of High pressure
processing
• 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. Temperature controller&
handling system
1.Pressure vessel
3. Pressure generating
device
2. Closure
HPP

18. Advantages &Limitations of High Pressure Processing
Advantages
• Kills vegetative bacteria(and spores at higher
temperatures)
• No evidence of toxicity
• Preserve nutritional quality of food
• Reduced processing times
• Uniformity of treatment throughout food
• Desirable texture changes possible
• In-packaging processing is possible
• Potential for reduction or elimination of
chemical preservatives
• Positive consumer appeal
Limitations
• Little effect on food enzyme activity
• Some microbial survival
• Expensive equipment
• Food should have approx. 40% free water for
anti-microbial effect
• Batch processing
• Limited packaging options

19. Pulsed Light Technology
• Principle of PLT:
• Also called as High Intensity Light
• Contains a broad spectrum of ‘white’ light, from UV wavelengths of 200nm to NIR
wavelengths of 1000nm
• Peak emissions between 400-500nm
• Emit 1-20 flashes per seconds 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 in flow,
increased cell membrane permeability and depolarization of cell membrane
• Decontamination and sterilization technology

20. Components & Applications of Pulsed Light technology
• 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. Treatment
chamber
1.High-voltage
power supply
3. Discharge
switch
2.Capacitor
PEF

21. Advantages & Limitations of Pulsed Light
Technology
Advantages
• Medium cost
• Very rapid process
• Little or no changes to foods
• Low energy input
• Suitable for dry foods
Limitations
• Only surface effects and difficult
to use with complex surfaces
• Not proven effective against
spores
• Possible resistance in some
micro organisms
• Reliability of equipment to be
established
• Lower penetration depth

22. Ultrasound
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 20kHz
• Frequencies <20 Hz are “Infrasounds” and Frequencies > 20kHz are “Ultrasounds”
• When ultrasounds 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 large in size during the expansion cycle, which increses gas diffusion , causing
the bubble to expand
• When the ultrasonic energy is insufficient to retain the vapour phase n the bubbles then rapid
condensation occurs
• The condensed molecules collide and create shock waves which create region of high
temperature and pressure .

23. 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 18-100kHz, high power, high
intensity (>1 W/cm2)
• Used for physical disruption and
acceleration of chemical reactions
High energy
Ultrasounds

24. Components and applications of Ultrasound
• Applications :
Crystallization, foam 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

25. Advantages & limitation of Ultrasound
Advantages
• Effective against vegetative cells
,spores and enzymes .
• Reduction of process times and
temperatures
• Little adaptation required of
existing processing plant.
• Heat transfer increased
• Possible modification of food
structure and texture.
• Batch or continuous operation
Limitations
• Complex mode of action
• Depth of penetration affected by
solids and air in product
• Possible damage by free radicals
• Sometimes need to be used in
combination with another process
(e.g.heating)
• potential problem with scaling- up
plant.

26. CONCLUSION
• Conventional processing Methods :
Cause thermal degradation of food
Loss of volatile compound , nutrients, colour, texture and flavour.
Longer processing time ,Higher fuel and energy required, combustion gases .
May generate environmental pollution
Emerging Food processing Technologies :
Produce food with better quality, acceptance and shelf life
Reduce the problem of environmental pollution
Higher heating rates and energy efficient process
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

27. THANK
YOU