This document discusses thermal and non-thermal food processing technologies. Thermal technologies discussed include blanching, pasteurization, and sterilization which use heat to destroy microbes and enzymes. Non-thermal technologies discussed include high pressure processing, food irradiation, pulsed light/electric field, and ultrasonics which achieve food preservation without heat. Both thermal and non-thermal technologies are aimed at reducing food losses and extending shelf life while ensuring food safety, though non-thermal methods maintain nutritional and sensory qualities of food better than thermal methods. The document concludes that a combination of thermal and non-thermal treatments may be most effective for food processing.

1. Thermal and Non-Thermal Technologies
in Food Processing
A Demo Lecture on
By
Dr. Vaibhav S. Patil

2. • Introduction
• Classification
• ThermalProcessingtechnologies
• Non-thermalProcessingtechnologies
• Conclusion
Content

3. • Sustainable solutions need to be developed for food and
agriculturalconsumptionpatternswithglobal food security.
• To protect food products from decay or pests an environment
friendly intervention strategy or methods required to develop
for global food security.
• Ultimately resulted in reducing losses and extending shelf life
of the product.
A need of an hour-novel food processing technologies
https://www.jbtc.com/foodtech/products-and-solutions/products/process-line-
control-and-automation/thermal-process-modeling/thermal-process-academy/

4. Thermal Processing
• Pasteurization
• Sterilisation
• Ohmic Heating
• Microwave heating
• Infrared heating
Non - Thermal Processing
• High Pressure Processing
• Irradiation
• Pulsed Light Technology
• Pulsed Electric Field
• Ultrasonics
• Oscillating Magnetic Field
• Radio frequency heating
Classification

5. • The basic purpose for the thermal processing of foods is to reduce or destroy
microbial activity, reduce or destroy enzyme activity and to produce physical
or chemical changes to make the food meet a certain quality standard. e.g.
gelatinization of starch & denaturation of proteins to produce edible food.
• There are a number of types of heat processing employed by the food
industry.
Introduction to thermal food processing technologies
Few of examples
• Mild processes – Blanching, Pasteurization
• More severe processes – Canning, Baking, Roasting, Frying

6.  Blanching The primary purpose of blanching is to destroy enzyme activity in fruits and
vegetables.
 It is not intended as a sole method of preservation, but as a pretreatment prior to
freezing, drying and canning.
Other functions of blanching include:
 Reducing surface microbial contamination
 Softening vegetable tissues to facilitate filling into
containers
 Removing air from intercellular spaces prior to canning
Letshave lookon basicthermaltechnologies
1. Blanching

7. • Purpose of Pasteurization is a relatively mild heat
treatment in which food is heated to <100°C.
• It is widely used throughout the food industry and is
frequently employed as a CCP in various HACCP plans.
• As a unit operation in food processing it can be used to
destroy enzymes and relatively heat sensitive micro-
organisms (e.g. non spore forming bacteria, yeast and
moulds).
• Is it used to extend shelf life by several days e.g. milk
or months e.g. bottled fruit.
2. Pasteurization
https://en.wikipedia.org/wiki/Pasteurization#/media/File:Simple_Pasteurization.png

8. http://www.tiselab.com/pdf/Thermal-Processing-of-Food.pdf

9.  High Pressure Processing is also known as “High Hydrostatic Pressure” or “Ultra High Pressure”
processing.
 HPP uses up to 900 MPa to kill many of the micro organisms found in foods even at room
temperature without degrading vitamins, flavor and colour molecules in the process.
 Food packages are loaded onto the vessel and the top is closed.
 The pressure medium usually water is pumped into the vessel from the bottom.
 Once the desired pressure is reached, the pumping is stopped, valves are closed, pressure can be
maintained without further need for energy input.
Principle: A principle underlying HPP is that the high pressure is applied in an “isostatic” manner
such that all regions of food experience a uniform pressure, unlike heat processing.
Non-thermaltechnologies
1. High Pressure Processing (HPP)

10. High Pressure Processing (HPP)
Technique by which products,
already sealed in its final package,
are introduced into a vessel and
subjected to a high level of
isostatic pressure (300–600MPa /
43,500-87,000 psi) transmitted by
water.
https://doi.org/10.1016/B978-0-12-822714-5.00003-6

12. Food irradiation (application of radiation to
food) is a ionizing technology that improves
the safety and extends the shelf life of foods
by reducing or eliminating microorganisms.
Like pasteurizing milk and canning fruits and
vegetables, irradiation can make different
food safer for the consumer.
2.Foodirradiation

14. • Thermal treatments is one of the oldest methods used for preservation, ensures the food safety.
• The extreme level of thermal treatment can preserve food up to 2 years in modified and
controlled atmosphere, can be performed in anywhere with a low cost
• Non-thermal processing technologies are do not use heating as the main means to inactivate
microorganisms and enzymes in food products.
• It has minimal effects on the colour, aroma, taste and nutritional value of food products while
ensuring high standards of food safety conditions
• Shorter treatment times, higher energy efficiency, higher levels of safety and a longer shelf-life for
foods.
• Therefore, in order to obtain safer, more healthy and better quality of food products, the
combination treatment may be a more effective processing technique for the food industry.
Conclusion