The document discusses various novel non-thermal food processing technologies that meet consumer demands for high quality and safe food. It explores methods including High Pressure Processing (HPP), Pulsed Electric Field (PEF) technology, Cold Plasma (CP) technology, and Ultraviolet (UV) light, highlighting their applications, benefits, and mechanisms. Additionally, it covers irradiation methods using gamma rays, electron beams, and x-rays for food preservation, along with their dosimetry and applications.

1. By
Thongam Sunita, Shaghaf Kaukab, Th. Bidyalakshmi, K. Bembem & Renu Balakrishnan
Scientists, ICAR-CIPHET

2. Introduction
Fig. Conventional and novel food processing
technologies
• Non-thermal technologies meet the
consumers demand for high quality, safe,
nutritious, and minimally processed food
• Ability to preserve foods without substantial
heating
• Retains their nutritional benefits and sensory
characteristics
• Reduction of energy and water consumption

3. Novel Non-thermal Technologies

4. High pressure processing

5. High pressure processing (HPP)
• Also called high hydrostatic pressure processing, pascalisation or high
pressure pasteurization
• Effectively inactivates vegetative bacteria, yeast and moulds
• Pressures from 100-800 MPa at ambient temperature
• Inactivate spores when combined with high temperature (High Pressure
Thermal Processing (HPTP))
• HPP retains sensory and nutritional quality of a liquid or solid, or chilled
products

6. HPP Principle
• Isostatic and Le Chatelier principle
Fig. 1a Schematic representation of a high pressure processing vessel Fig. 1b Profile of pressure and temperature during HPP

8. HPP Equipments

9. HPP Applications
• Increasing the shelf life of foods
• Thawing of foods
• Functional and physical modifications of foods
-starch gelatinization,
infusion of food value compounds, etc.
forced water absorption,

10. Commercial HPP Products
• First commercial HHP-processed foods were launched in 1990 as fruit
products (jams)
• Retort rice products, cooked hams and sausages, soy sauce, beverages,
etc.
Fig. Strawberry, apple, and blueberry jams; Rice cake; Retort rice products

11. Pulsed electric field

12. Pulsed electric field (PEF) technology
• Application of high voltage (20 to 80 kV/cm) for short time (ms or µs) to
foods placed between two electrodes
• Mainly used as preservation technology
• It destroys vegetative bacteria, yeast and moulds but not spores and not
many enzymes.
• Suitable for liquid or semi-solid food and solid food products
• Food must be aseptically packaged and properly stored under
refrigeration

13. PEF Processing System
Fig. Schematic diagram of a general PEF-based food processing system (pilot scale)

14. Fig. Electroporation of cell
PEF effect on cell

15. Figure 2: Fruit juices treated with PEF technology and example of a PEF unit on an
industrial scale
Pulsed electric field (PEF) technology

16. • Pasteurization of liquid foods (juices, milk & dairy products, soup and
liquid eggs etc.)
• Enzyme deactivation
• Extraction (sugar from beetroot, juice from grapes or apple, and
bioactive compounds )
• Bio-active compounds recovery
• Meat processing (beef)
• Dehydration
• Wine processing
• Pre-sowing seeds treatment
• Manufacturing of French fries
PEF Applications
Fig. Dried strawberry: pre-treated (left) & non pre-treated (right)
with PEF

17. PEF Benefits

18. Cold Plasma Technology

19. Cold Plasma (CP) Technology
• Plasma: ionized gas containing reactive oxygen species (O, O2,O3, & OH),
reactive nitrogen species (NO, NO2, & NOx), UV, free radicals, and charged
particles
• Plasma is generated when
electrical energy is applied to a gas
present between two electrodes
• CP: ionized gas is formed by
relatively low energy (1–10 eV) and
electronic density (up to 1010 cm-3)
• Gases used in food applications are argon (Ar), helium (He) and air
• Electrode material are steel, aluminum, brass, iron, and copper

20. Fig. Streamer theory
CP Generation

21. CP sources for food applications
Fig. Cold plasma systems: (a) Dielectric barrier discharges, (b) Plasma jet, (c) Corona discharges, (d) Radiofrequency plasma (d1)
Inductively coupled, (d2) Capacitively coupled radio frequency plasmas (CCP), and (e) Microwave plasma source
DBD
(b) PJ
MW
(d) RF

22. CP applications
• Dielectric barrier discharge plasma is used for food treatment in-package
(packaged cherry tomatoes), enzyme inactivation (tender coconut water,
carrot juice)
• Plasma jet in inactivation of bacteria in particulate foods (rice germ,
black pepper powder, and sesame)
• Corona Discharge plasma in pesticide degradation on grapes and
strawberries
• Radiofrequency plasma in starch modification (corn)
• Microwave plasma works for surface sterilization or decontamination
(washing of fresh-cut lettuce)
• Protein allergenicity inhibition, Food packaging materials modification

23. CP Equipments
Fig. Benchtop plasma treatment systems (Henniker Plasma company)
(surface activation, cleaning and modification of a wide range of materials
including polymers, metals, glass and ceramics)
Fig. Cold plasma treatment ‘Coplas clean’
(Riedel Filtertechnik)
(Eliminates odour molecules in the tobacco,
tire, fish, seed, food and pet food industry)

24. Ultraviolet light

25. Ultraviolet light
• UV is non-ionising radiation (100-400
nm)
• Germicidal properties at wavelengths
of 200–280 nm
• Used for surface treatment and as a
nonthermal alternative for fluid foods
and ingredients
Fig. UV radiation and wavelengths, and mechanism involved in microbial inactivation.

26. Ultraviolet light sources
• Commercially available UV sources: low- and medium-pressure
mercury lamps (LPM and MPM), pulsed light (PL), and light-
emitting diodes (LEDs)
• Low-pressure mercury lamps are the most favored for most
germicidal applications
• Pulsed UV light lamp emit high power UVC light at regular intervals,
(1 μs - 0.1 s; 200–1100 nm)
Fig. Schematic diagram of UV-C
radiation device.

27. Parameters related to UV light processing
D (J/m2)=I × t,
where I=intensity
t=exposure time
UV irradiance or
UV intensity flux

28. Impact of UVC radiation

29. Advantages & Limitations of UVC radiation

30. • UV radiation has been successfully applied to fluid food
matrices and surfaces
• Pasteurization of milk and juices
Impact of UVC radiation

31. Ultrasound processing

32. Ultrasound generation
• Ultrasound refers to sound waves with frequencies above 20 kHz
High frequency ultrasound
Power ultrasound
• Frequency=20-100 kHz
• Sound intensity= 10-1000 W/cm2
• Frequency=2-20 MHz
• Sound intensity= 100 mW/cm2 -1 W/cm2
• Used in food safety applications
• Piezoelectric effect or piezoelectricity is the physical concept for generation of ultrasound
• Ultrasound transducer: contains a piece of piezoelectric ceramic material (barium titanate,
lithium sulfate, lead metaniobate, or lead zirconate titanate) sandwiched by two
electrodes; upon application of frequency alternate voltage to the electrodes, the
piezoelectric material starts to vibrate rapidly and generate ultrasonic waves

33. Propagation of Ultrasonic waves
• Most ultrasound applications involve a liquid

34. Phenomenon of ultrasound application
Fig. Formation of acoustic cavitation bubbles

35. Ultrasonic Processing Systems
Fig. (a) Ultrasonic probe system and (b) Ultrasonic bath (Crest Ultrasonics)
Probe system (or ultrasonic horn)
• Most widely used
• Perform a target operation
• High-power dissipation per unit area
• System with 500 to 600 W (laboratory) and 16000 W
(commercial)
• Operated in batch or continuous mode
• A number of probe units can be connected in series or
in parallel (continuous mode
Bath system (or Tank system)
• Consist of transducers (bottom), bath filled with water
(or disinfector added)
• Used for cleaning applications
• Food produce surface decontamination
• Acoustic power density is lower than that of probe
systems
Dual-/Multi-Frequency Ultrasound System
Airborne Ultrasonic System
Focused Ultrasound System

36. Applications
• Pasteurization (thermal sonication and mano-thermo-sonication) of liquid food
such as apple cider, orange juice, carrot juice, mango juice, milk, etc.
• Surface Decontamination of Fresh Produce (spinach, apple, etc.)
Fig. An automatic oak wine barrel cleaning
system using a 4 kW ultrasonic transducer
(Cavitus Pty Ltd.)

37. Gamma Ray, Electron Beam, and X-ray
Irradiation

38. Introduction
• Ionizing radiation to kill bacteria in foods was patented in the early 20th century
• USFDA approved food irradiation for wheat, spices, meat, poultry, fruits, and
vegetables

39. Gamma-ray, X-ray, and electron beam
Fig. Electromagnetic spectrum
• Gamma-ray, X-ray, and electron
beam are ionizing radiations
• Ionizing radiation technologies used
for food applications
• Gamma radiation sources are
(cobalt–60 with emission energy
levels of 1.17 and 1.33 MeV and
cesium-137 with emission energy of
0.66 MeV) Cobalt–60
• Main source of gamma
irradiation
• Half-life of 5.27 years
Cesium-137
• Half-life of 30.17 years

40. • Electron beams are high energy electrons
• 10 MeV (maximum level) is allowed for food application by U.S. FDA.
• Electron beams are produced by a particle accelerator
• Penetration ability of electron beam is 3.9 cm for 10 MeV in high moisture foods

41. • The international unit for the radiation dose is the Gray (Gy)
• One Gray is one joule of energy absorbed by one kilogram of water
• Dosimetry is the measurement and calculation of absorbed doses
Dose and Dosimetry
Applications
• 0.2–1.0 kGy are used for disinfestation of fruits and vegetables
• 1–5 kGy can be used to inactivate vegetative bacteria
• >10 kGy are used for sterilization of dry foods such as spices, herbs,
Fig. Radura
(International food
irradiation symbol)

43. THANK YOU