The document gives insight about the modified atmospheric packaging of foods

1. A
SEMINAR
ON
“DEVELOPMENT IN MAP”
SUBMITTED BY: VILAS ( PG/FT/088)
SUBMITTED TO: Dr. P. Kumar
Sant Longowal Institute Of Engineering And Technology, sangrur,
Punjab

2. Combining MAP with
Other Preservative
Technique

3. Combining MAP with other
Preservative Technique
• Used for many food products and getting and
commercial and economic reality.
• Mild preservation method.
• Other steps is necessary in addition to MAP.

4. Most common preservative method
• High temperature
• Low temperature
• Water activity
• Acidity
• Redox potential
• Principle based on hurdle technology
• Preservation of food is achieved by disturbing
temporary or permanently homeostasis of
microorganism in food

5. Preservation Focused on Specific
Groups of M.O.
• Types and no of Microorganisms in the raw material
have direct effect on effectiveness of MAP
• Shelf life extension obtained with MA does not always
give same extension in safety
• Pathogenic bacteria may gain advantages when
competitive flora is inhibited
• For chilled product, psychotropic pathogens are target

6. Contd…
• Heat treated ready meals spore forming clostridium and bacillus
are target
• Five food born pathogenic bacteria known to be capable of
growth below 5 C
1. Bacillus cereus
2. Non proteolytic C. botulinum
3. Listeria monocytogens
4. Yersenia entrocolotica
5. Aermonous hydrophilia
• Most food spoilage mold species have an absolute
requirement for O2 and appear to be sensitive of high level
of CO2

7. Heat Treatment and Irradiation
• MA packaging of cook-and-chill foods commonly used for
processed minimal heat-treated ready meals.
• Success of heat treated ready meals results primarily form
inactivation of vegetative Microbial Flora by Mild heating
• Mild heating destroy cold growing fraction of potential
spoilage flora with minimal thermal damage
• Heat processing equivalent to 90 C for 10 min is sufficient to
ensure inactivation of spores of psychrotrophic stains of C.
botulinum

8. Low Temperature
(Freezing, Partial Freezing, super chilling)
• Low and stable temperature is general requirement of many
MA product
• Enzymatic and microbial activity are greatly influenced by
temperature
• Psychotropic organisms grow very slowly with extended lag
phases at temp 0 °C
• Frozen ( - 20 ° C ) Cod Fillets in MA had longer shelf life than
raw Cod Fillets in MA.
• Experiment with whole gutted salmon have shown that MAP
combine with super chilling to extend further shelf life and
safety of fresh fish

9. Irradiation
• Irradiation below the threshold dose, enhance the attractiveness
of MAP.
• Effects of MAP/ Irradiation on sensory properties.
• Depletion of Vitamins content during storage compare to
untreated items.
• Several studies have been carried out on the use of MAP/
irradiation in fish products.
• Sensory shelf life of Irradiated MA cod and Irradiated vacuum
packaged cod was > 24 days
• non-irradiated MA cod shelf life < 14 days and for vacuum
packed cod < 9 days.

10. Contd….
• Several issue like legislative, scientific and
consumer attitude towards irradiated foods
need to be resolved

11. Preservatives
• Benzoic acid, Sorbic acid efficient inhibiting
microbial growth i.e. bacterial and fungal cells
• There effects strongly dependant on pH
• CO2 – O2 atmosphere combine with 1 % K
sorbate ice mostly used

12. Sodium chloride
• NaCl is old preservative agent with antimicrobial
properties
• Fish species have been studied after being subjected
to 5 min treatment in brine solution + packed in
different gas mix and results are
1. Delay in chemical , Microbial and sensory alternation
2. Microbial levels were significantly lower
3. Reduced exudation and Higher water binding capacity

13. Alternation of pH
• Influence spoilage due to its effects on microorganism
and enzyme activity
• The effect of pH on solubility i.e. CO2 can dissolve in
aqueous food with higher pH level
• Beef with pH 6.3 in 100% N2 at 5 C supported the
growth of E. cloacae but not at pH 5.4
• In muscle foods, decline in pH is reversed in later
stages of post mortem change .

14. • This may be inhibited by addition of buffer
compound polyphosphate and it has
preservative role by
1. Acting as a metal ion chelators
2. Acting as pH buffers
3. Interacting with protein promote hydration and
water binding capacity
4. Preventing lipid oxidation and microbial growth

15. Organic Acids
• Undissociated molecules of organic acids such as
Lactic, Citric and Malic and Acetic acid esters posses
AMA
• The addition of Na – lactate + MA packed - cooked
meat products – significant shelf life extension ( more
prounced at low temperature)
• Buffered Lactic acid + MAP – inhibitory effect Listeria
monocytogens – shelf life increase

16. Essential oils
• Regarded as natural alternatives to chemical
preservative
• Volatile compounds of oregano essential oils capable
of affecting growth of spoilage causing M.O.
1. Inhibit metabolic activity
2. Minimizing flavor concentration

17. Other Techniques
• Na2Ca EDTA
• Soluble Gas stabilization
• Protective microbes and there bacteriocin
- antibacterial proteins produced by lactic
acid bacteria (LAB)

18. Consumer Attitudes
• MAP is regarded as a mild preservation method
by most consumers
• A development towards using more preservative
in combination with MAP with less recognized
effects lead to lowering consumer acceptance
for MA packaged foods

19. Integrating MAP with
New germicidal
Techniques

20. Introduction
• Food spoilage which occurred depends upon
1. Properties of food
2. Physical structure
3. Types of M.O. present
4. Environment in which food is kept
• Selecting correct mix of gases for the MA
depends upon visual appearance and shelf –life

21. Contd……
• In UK, demand for MA packed foods due to
1. Extension of shelf life by 50 – 500%.
2. Minimization of waste .
3. Quality, presentations and visual appeal – all
improved.
4. Reduction in use of artificial preservatives .
5. Increased distribution distance of products.

22. New Germicidal Techniques
• Foods spoilage rate can be can be slowed down
by combining germicidal and MAP
techniques
• Both UV and Ozone are able to kill M.O.
• combination of these techniques with MAP
results in safer products and extended shelf
life.

23. UV Radiation
• UV radiation is a form of energy which observed and bring about
structural changes of system.
• Exposure of microbiological system to UV radiation within the
wavelength dissociate the DNA
• Most common source for producing light is the low pressure mercury
lamp
• Able to kill m.o by using wavelength within the germicidal region
• 254 nm wavelength emitted form mercury discharge is ideal for the
action

24. UV Radiation Generation by low
Pressure Mercury Lamp

25. Ozone
• Toxic and its concentration above 5 ppm are required
for significant microbial effect in short exposure time
• Naturally occurring disinfectant and oxidizing agent
• Instability causes oxidation reactions, by collision
between ozone molecule and microorganism
• Bacterial cells and viruses are split or inactivated
through oxidation of there DNA

26. • Methods for Ozone generation
1. Corona discharge
2. UV radiation
• Dosage of ozone for E.coli bacteria is 0.5 ppm
of water with killing rate of 99 %

27. Integrating with MAP
• There are the certain range of machine
1. Form – Fill – Seal machine
1. Horizontal
2. Vertical
- VFFS machines are suitable for gravity – fed- loose
products such as coffee, snack products, grated
cheese, salads etc
2. Thermoform – fill – seal ( Multivac Rollstock
Machine)
3. Vacuum chamber
• .

28. Contd……
• Choice of film for MAP is largely determined by there
gas and water vapor transmission rate
• Materials such as polyester, nylon, PVdC and EVOH
provide good gas barrier but having poor WVTR
• Polyethylene, polypropylene, ethyl vinyl acetate
have gas transmission rate too high to maintain a
chosen gas mixture or vacuum for long enough to
provide adequate shelf life

29. Installation of UV/ Ozone system
• U.V./ Ozone lamp has been incorporated into roll stock
Machine
• Food is exposed to the ozone or UV before the lidding material
is applied to the packaging
• Lamp is able to produce UV and Ozone either separately or in
combination
• Gantry type arrangement to position the lamp above the food
trays, allows the lamp and reflector clearly to illuminate the food
trays with UV, Ozone or its combination

30. Lidding Material

31. Detecting Leaks in
MAP

32. Introduction
• Package integrity - requirement for high quality
of sterilized and MAP food.
• package integrity problem is leaking seals, in case
of flexible plastic packages.
• Non-destructive package leak testing equipment
detects defective packages immediately in
packaging line.
• In many studies leakages of around 10 m in
diameter - demonstrated to cause microbial
contamination in commercially processed and
packaged aseptic packages

33. Package leak detection during
processing
• Methods in use
• Destructive methods- biotest, electrolytic test, dye
penetration test and bubble test.
• In-line non-destructive test equipment meet demands
1. reliable identification and rejection of all the defective
packages produced;
2. fast leak detection;
3. non-damaging to the product;
4. easy to use and maintain; and reasonable supply and
operating costs.

34. Contd…
• Most non-destructive leak inspection systems for flexible and
semi-rigid packages are based on a stimulus response technique
• Tracer gas detection is a very sensitive method, detection of
pressure differential is perhaps currently the most popular
method.
• Commercial pressure differential methods are typically based
on
1. detection of an external rise or fall in pressure in a test chamber created
outside the package with compressed air or a vacuum pump
2. detection of an internal fall in pressure created inside the package either
mechanically or by heat

35. Novel tracer gas system for in-line
application
• Tracer gas leak detection methods are very sensitive
• Most commonly used gas are helium, carbon dioxide as a tracer
gas.
• Automatic in-line leak detectors based on helium or carbon
dioxide tracer gases are not successful,
1. Relatively high operating and supply costs of the helium method
2. Unfavourable physical characteristics of the carbon dioxide method.
A novel leak-detection system has recently developed at VTT
using hydrogen as a tracer gas
H2 has many characteristics advantageous i.e. colourless,
odourless, tasteless and non-toxic gas at atmospheric
temperatures and pressures.

36. Package leak indicators during
distribution
• MAP for non-respiring food typically has a low (0–2%) oxygen
concentration and a high (20–80%) CO2concentration.
• Visual oxygen indicators
• first commercialise O2-absorbing sachets under trade name
‘Ageless’25 , Ageless-Eye sachets containing an O2 indicator
tablet designed to confirm that ‘Ageless’ absorbers are
functioning properly
• A typical visual O2 indicator consists of a redox dye & alkaline
compound.

37. Contd….
• The redox dyes of the indicators are oxidised by O2 and
a colour change can be observed.
• Dye used in the indicators - methylene blue, 2,6-
dichloroindophenol.
• Development of two-step colour reaction for
constructing a visual O2 indicator.
• First reaction step O2-sensitive material is oxidised and
the formation of an acid or peroxide occurs.

38. Invisible oxygen indicators
• Luminescent dyes quenched by O2 as indicators for food
packages.
• Optical method used for quantitative measurement of O2
concentration
• Optical oxygen-sensing method developed at TNO
measurement principle is based on the fluorescence
quenching of a metal-organic fluorescent dye, which is
immobilised in a hydrofobic polymer.

39. Carbon dioxide indicators
• CO2 used as a protective gas in MAP
• CO2 produced in microbial metabolism, accumulation in a
package headspace can be considered to be a sign of microbial
growth.
• Reversible CO2 indicator suitable for MAP, consists of, five
indicator strips.
• Strips contain CO2-sensitive indicator material consisting, anion
and a lipophilic organic quaternary cation
• Colour change of each strip take place when the CO2
concentration is below a certain limit
• Sealed Air Ltd has produced a visible CO2 indicator for MAPs.

40. THANK YOU