The document discusses novel approaches for seafood preservation, including modified atmospheric packaging (MAP), irradiation, ozone treatment, pulse electric fields (PEF), ultraviolet radiation, oscillatory magnetic fields (OMF), high pressure processing (HPP), ultrasound technology, and high intensity light (HIL) preservation. It provides details on the mechanisms and advantages of each technique. While these novel approaches help extend shelf life and maintain food safety and quality compared to traditional methods, further investigation is needed to improve their effectiveness for seafood preservation.

2. ASSIGNMENT
On
NOVEL APPROACHES IN
SEAFOOD PRESERVATION
TECHNIQUES
Presented By:-
Dr.Irshad A
MVSc Scholar, LPT Division

3. Introduction
Why preservation is important?
Seafoods are perishable products
Shelf life is limited in the presence of oxygen and
air
Very good medium for aerobic spoilage organisms

4. Basis of preservation
Control of temperature
( Refrigeration & Freezing)
Water activity
Microbial load
Availability of oxygen

5. Ancient methods of preserving fish
Drying:- Water activity
Smoking:- Water activity & Microbial load
Freezing:- Temp control
Canning:- Microbial load
Salting:- Water activity
Fermentation and Pickling:- Water activity

6. New Techniques
1. MAP TECHNIQUE
2. IRRADIATION TECHNIQUE
3. OZONE TECHNIQUE
4. PEF
5. UV RADIATION
6. OMF
7. HPP
8. ULTRASOUND TECHNOLOGY
9. HIL

7. 1. Modified Atmospheric Packaging (MAP)
 Air in side the pack is replaced with single gas or mixture of gas
 Used in various food product such as
• Raw & cooked red meat
• Poultry
• Fruits
• Coffee and tea
• Vegetables
• Bread and cheese
• Fish and sea foods

8. Modified Atmospheric Packaging (MAP)
 MAP together with refrigeration is use in sea foods
Shelf life depend on
 Raw materials
 Temperature
 Gas mixture and proportion- low conc. of O2
High conc of CO2 and N2
 Gas/product ratio
 Packaging material used

9. Modified Atmospheric Packaging (MAP)
Commercially used gases are
CO2, O2, & N2
CO, N2O, NO, SO2, Cl2 and ethane
Xenon, Argon & Helium
Combinations usually used are
CO2/N2/O2=40:30:30 for white fish and shellfish
CO2/N2=60:40 for fatty and smoked fish
In1992 (UK sea food authority) a patent was issued for a gas
mixture-50-80% CO2, 5-20% O2 and 27-45% Ar
-slow down enzymatic reaction and microbial development

10. Modified Atmospheric Packaging (MAP)
Success of MAP
GMPs
HACC Programs
Proper temperature control during storage and distribution
Disadvantage:
•Lower Temperature is needed
•Growth and toxin production by Clostridium botulinum type E
•There is a change in composition of micriflora in product

11. 2.IRRADIATION TECHNIQUE
 Old food preservation technique
 Began in 1957 Germany to improve quality of
spices
Physical treatment involving direct exposure of
food product to electrons or EMRs to
preserve food.
For Sea foods preservation
• Gamma rays
• X-rays
• Accelerated electron beams are used

12. 2.IRRADIATION TECHNIQUE
For Gamma rays:- Co 60 & Cs 137
Mechanism:-
Irradiation with high energy radiation leads to the
breakdown of chemical bond and form free radicals and ions
in microorganism, which leads their destruction.
Dose rate:- 2 – 8 kGy
UK Food Irradiation Legislation Permits only 3kGy radiation
for fish and shell fish.

13. 2.IRRADIATION TECHNIQUE
Disadvantage:-
•Undesirable sensory changes
•Low conversion efficiency
•Limited penetration in sea and shell foods
•Licensing is tightly regulated
•Consumer concern about Cs 137

14. 3. Ozone Preservation Technique
Effectively Used in
•water treatment
•Cleaning and sterilization of plants
Mechanism:
Molecular Ozone and its Decomposed product are effectively
destroy micro organism including bacteria, virus and fungi by
their effect on microbial intercellular enzyme, nucleic acid, and
other cellular components.

15. 3. Ozone Preservation Technique
Advantages:-
O3 reduce the superficial contamination of fish as well as the
formation of volatile N2 compound.
O3 increase the shelf life of the fish products and sensory quality
Does not produce any toxic residue

16. 4.Pulse Electric Fields method (PEF)
 Physical Non thermal Preservation Method.
 Use of electric field to eradicate food borne pathogen and to
control spoilage microorganism in food.
 Used as a replacer of thermal pasteurization of foods
 Mainly Used in liquid foods and some fish products
Efficiency of PEF depends on;
 Electric field strength
 Treatment time
 Bacterial features

17. 4.Pulse Electric Fields method (PEF)
Advantages:-
It preserve quality attributes of foods.
Improve nutritional value of some foods
Increase sensory quality
Control the microbiological safety of product.
Disadvantages:-
•Ineffective in enzymes and spores
•Safety concern in processing environment
•Adverse effect in foods
•Affect the texture and microstructure of meat and fish

18. 5.Ultraviolet (UV) Radiation tech.
• Non thermal and environmental friendly
• Exposure of the product to a germicidal light with
a wavelength to inactivate bacteria and viruses.
Classification of UV radiations
UV-A(Near UV) -315 to 400nm
UV-B(Mid UV)- 280 to 315 nm
UV-C(Far UV)- 100 to 280nm

19. 5.Ultraviolet (UV) Radiation tech.
Mechanism:-
•Micro-organism absorb UV light(at 254nm) Physical shifting
of electrons breaking bond in DNA preventing growth and
reproduction.
•UV-C is more effective than others
In food industry mainly used for
Sterilization of food contact surface
Water used of washing foods
Air sanitation in meat and vegetable processing plant.
Reduction of pathogen in fruits, veg, red meat, fish and fish
product, poultry etc

20. 5.Ultraviolet (UV) Radiation tech.

21. 6.Oscillatory Magnetic Fields(OMF)
 Non thermal physical process
 Usually used along with conventional preservation techniques
 First proposed in 1985, US patent to Hofmann.
 Very low degradation in sensory and nutritional property
 In OMF, Food is sealed in a plastic bag and subjected to 1 to 100
pulses in an OMF with a frequency between 5 and 500kHz at 0
to 50oC for a total exposure time 25 to 100 microseconds
 For seafood preservation- 5 to 50 Khz and intensity 5 to 50 Tesla
is used.(The te sla (symbo l T) is the SIde rive d unit o f mag ne tic flux de nsity, co mmo nly de no te d as B)

22. 7. High Pressure Processing(HPP)
 Application of Very High Hydrostatic Pressure ranging from
100 to over 1000MPa at temp of 0 to 100oC, with varying
holding time.
 Holding time depends on food.
 It inactivate enzymes and microorganisms
 Minimal effects on food quality
 First commercialized in Japan 1992
 Used mainly in
 Ham
 Rice products
 Fish and shellfish

23. 7. High Pressure Processing(HPP)
Advantages:
Increased shelf-life (2 to 4 times longer than the same product
without HPP, stored at the same temperature).
Easier and higher yield shucking and meat extraction (20% – 50%
more meat).
Product freshness.
No Impact on sensory, nutritional or functional properties.
Effective elimination of spoilage and pathogenic micro-organisms.
Greater tolerance to cold chain abuse.

24. 7. High Pressure Processing(HPP)
Limitations:
High cost equipment
Long cycle times
Increased metal fatigue.

25. 8.Ultrasound Preservation Technique

26. 8.Ultrasound Preservation Technique
Limitations
High energy consumption
Long treatment times
Complex mode of action
Need to be used in combination with another process(eg:heating)
Undesirable sensory changes

27. 9. High Intensity Light Preservation
 Also called,
Pulsed UV light, Pulsed light, Broad Spectrum White light.
 Alternative technique for thermal preservation
 Intense light pulse is used for preservation
 Bandwidth between 200 to 280 nm( UV-C)
Mainly used for:-
 Surface sterilization of baked goods, veg, fruits sea foods and
meats
 Micro-organisms such as L.monocytogenes, S. enteritidis, Ps.
aerogenosa, B. cereus, St. aureus were reduced in 200 pulse
light(ie pulse duration, 100ns)

28. 9. High Intensity Light Preservation
Limitations
Only applied for clean surfaces
Cause severe blindness on accidental exposure
Limited use in opaque food stuffs
Produce undesirable sensory changes

29. Conclusion
Food preservation techniques extend shelf life of the
products while maintaining food safety and quality
To improve the effectiveness of preservation
techniques, two or more tech can be combined.
For efficient preservation, US, HIL, PEF etc on sea
foods need to be investigated.