This document provides an overview of modified atmospheric packaging and storage techniques for enhancing fruit quality. It discusses the benefits of modified atmosphere packaging (MAP) in reducing post-harvest losses and extending shelf life. The document outlines the optimal gas composition ranges for different fruits, as well as methods for creating modified atmospheres, either passively through film permeability or actively through gas flushing. It also reviews packaging materials and techniques used in MAP and provides case studies demonstrating the effectiveness of MAP for extending storage times of fruits like litchi, pineapple, mango and guava.

1. Modified Atmospheric Packaging
and Storage For Enhancing
Fruit Quality
1

2. CONTENTS
1. Modified Atmosphere, packaging and storage
2. Controlled Atmosphere and Modified Atmosphere
3. Need For Modified Atmospheric Packaging (MAP)
4. Beneficial effects of MAP
5. Harmful effects of MAP
6. Methods of creating modified atmosphere
7. Principles of preservation by MAP and gases involved
8. Packaging materials and techniques in MAP
9. Case studies
10. Conclusion
2

3. Modified Atmosphere, Packaging and Storage
• Modified atmosphere (MA) means any deviation from the normal
atmospheric gas composition.
• The normal air comprises of 78.08% nitrogen (N2 ), 20.95% oxygen (O2 )
and 0.03% carbon dioxide (CO2 ).
3

4. • The primary factors in maintaining quality and extending the postharvest life of
fresh fruits are -
- Harvesting at optimum maturity
- Minimizing mechanical injuries
- Using proper sanitation procedures
- Providing the optimum temperature and RH during all marketing steps
• Secondary factors include -
- Modification of O2, CO2, and/or C2H4 concentrations in the atmosphere
surrounding the commodity to levels different from those in air.
This is referred to as Controlled Atmosphere (CA) or Modified Atmosphere
(MA).
4

5. • If this deviation is strictly controlled, as in cold storage systems, for
the specific gaseous concentrations, it is termed as Controlled
Atmosphere (CA).
• If there is no control of the gas composition throughout the storage of
the commodity due to continued respiratory processes (as in case of
unit packs), it is termed as Modified Atmosphere (MA).
• CA implies a greater degree of precision than MA in maintaining
specific levels of O2, CO2, and other gases. Alongside CA/ MA
conditions, management of recommended temperature and relative
humidity for the particular commodity is also important. (Kader et al.,
1986)
Controlled Atmosphere and Modified Atmosphere
5

6. •Fruits and vegetables are classified as highly perishable food
materials.
• These are seasonal in nature and are rich sources of minerals,
vitamins, dietary fibre, fructose and moisture.
• Under ambient conditions, their shelf life varies from few days to
weeks. Hence, these can be stored in raw form at lowered
temperatures of 0 to 15°C and 80 – 95% RH, with appropriate
gaseous composition (Modified Atmosphere) depending upon the
type of produce.
• The level of processing in India has been extremely low about
2% of the total production of fruits and vegetables.
Need for MAP
6

7. • It is estimated that in India, quantitative and qualitative losses to
horticultural produce in post harvest phase are about 20-25% of the
production.
• MAP and MAS can be effectively utilized in reduction in post
harvest qualitative and quantitative losses, enhancement of shelf life
till the produce reaches the table of the consumers, value addition
in order to produce products desired by the consumers in the form,
shape, size, colour, texture packaging and price.
7

8. • Quantitative and qualitative reduction of postharvest losses.
• Retardation of ripening, senescence and physiological changes.
• Alleviation of physiological disorders such as chilling injury.
• Reduction in decay incidence and severity due to elevated CO2.
• Effective control of insect infestation due to reduced level of O2.
• Reduction in retail waste in MAP products.
• Hygienic stackable MA packs, sealed and free from product drip and
odour.
Beneficial effects of MAP
8

9. • Development of off-flavours and off-odours at very low O2
concentration as a result of anaerobic respiration.
• Increased susceptibility to decay when the commodity is
physiologically injured by too low O2 or too high CO2
concentrations.
• Initiation or aggravation of certain physiological disorders e.g. brown
heart in apples and pears.
• Irregular ripening of fruits e.g. in case of banana at level of O2
below 2% and CO2 above 5%.
Harmful effects of MAP
9

10. The minimum O2 concentration tolerated by different fruits :
Minimum O2 tolerated
(%)
Fruits
0.5 Tree nuts and dried fruits
1.0 Some cultivars of apple and pears, most cut or sliced fruits
2.0 Most cultivars of apples and pears, kiwifruit, apricot, cherry, nectarine,
peach, plum, strawberry, papaya, pineapple
3.0 Avocado and persimmon
5.0 Citrus fruits
Kader et al., 1992
10

11. The maximum CO2 concentration tolerated by different fruits:
Kader et al., 1992
Maximum CO2
tolerated (%)
Fruits
2 Apple (Golden Delicious), Asian pear, European pear, apricot, grape
5 Apple, peach, nectarine, plum, orange, avocado, banana, mango,
papaya, kiwifruit
10 Grapefruit, lemon, lime, persimmon, pineapple
15 Strawberry, raspberry, black berry, blueberry, cherry, fig
11

12. The recommended MA conditions for different fruits are :
Kader et al., 1992
Fruit crop Temperature
(°C)
Relative
Humidity (%)
O2(%) CO2(%)
Apple 0-5 90 1-3 1-3
Apricot 0-5 90 2-3 2-3
Banana 13-15 90-95 2-5 2-5
Orange 3-9 90-95 5-10 0-5
Peach 0-5 90-95 1-2 3-5
Pear 0-5 90-95 2-3 0-1
Strawberry 0-5 90-95 4-10 10-15
12

13. 13
Fruit crop N2(%) O2(%) CO2(%)
Avocado 85-95 2-5 3-10
Grapes 92-97 2-5 1-3
Grapefruit 80-92 3-10 5-10
Kiwifruit 93-96 1-2 3-5
Lemon 80-95 5-10 0-10
Mango 85-92 3-7 5-8
Papaya 87-93 2-5 5-8
Pineapple 85-93 2-5 5-10
Sandhya, 2010

14. Examples of CA injury
Crop and cultivars CO2 injury level CO2 injury
symptoms
O2 injury level O2 injury symptoms
Apple , Red
Delicious
>3 % Internal browning <1 % Alcoholic taste
Apple , Fuji >5 % CO2 injury <2 % Alcoholic taste
Apple, Gala >1.5 % CO2 injury <1.5 % Ribbon scald
Apricot >5 % Loss of flavour <1 % Off-flavour
Banana >7 % Green fruit softening <1 % Brown skin,
discolouration
Cherry >30 % Brown
discolouration
<1 % Skin pitting, off-
flavour
Mango >10 % Softening <2 % Skin discolouration
14

15. • Passive modified atmosphere packaging:
Modified atmospheres can passively evolve within a hermetically sealed package
as a consequence of a commodity’s respiration, i.e. O2 consumption and CO2
evolution.
If a commodity’s respiration characteristics are properly matched to film
permeability values, then a beneficial modified atmosphere can be passively
created within a package.
Methods of creating modified atmosphere conditions
15

16. • Active modified atmospheric packaging :
By pulling a slight vacuum and replacing the package atmosphere with a desired
mixture of CO2, O2 and N2, a modified atmosphere can be created very quickly.
Another active packaging technique is the use of O2, CO2 or ethylene
scavengers/emitters. Such scavengers/emitters are capable of establishing a rapid
equilibrium atmosphere within hermetically sealed produce packages.
Methods of creating modified atmosphere conditions
16

17. • In MAP the shelf life of packed food is extended as compared to
normal packaging but in order to prevent food safety hazards (stop
the growth of pathogenic bacteria) MAP packaging must follow the
additional criteria like :
1. Water activity of food maintained below 0.92
2. pH is below 4.5
3. Use of sodium nitrite or other preservatives
4. Temperature is maintained below 3°C
Additional criteria in MAP
17

18. Principles of preservation by MAP/CAP
Reduce
respiration rates
in fruits
Reducing
moisture loss
Reduce growth of
spoilage
microorganisms
Reducing
oxidative changes
Slow down
biochemical and
enzymatic activity
18

19. Factors involved in designing modified atmosphere and humidity
Mahajan et al., 2014
19

20. • Oxygen :
Properties -
Colourless, odourless and highly reactive
Low solubility in water
Promote oxidation, browning and enzymatic oxidation
It’s required for most bacteria and fungi growth
Advantages-
Generally required in more proportion in meat packaging to retain red
colour pigment.
It is required in less proportion in MAP of fruits.
Gases used in MAP
20

21. • Carbon Dioxide
Properties -
Colourless with slightly pungent odour.
High solubility in water.
Prevents oxidation, browning and enzymatic oxidation.
Prevents growth of microorganisms bacteria and moulds growth.
Advantages - Extend shelf life
Reduces pH of food
Reduce oxidative reactions
Affect growth of gram positive bacteria
21

22. • Nitrogen -
Properties -
Inert, colourless, odourless and tasteless
Low solubility in water and food
Do not support oxidation, browning and enzymatic oxidation
Do not support the growth of microorganisms
Advantages - Extend shelf life
Reduce oxidative reactions
Affect growth of microorganisms
• Noble Gases -
Helium (He), Argon (Ar) and Xenon (Xe) to replace N2 as the balancing gas in MAP.
Noble gases can also be used to preserve and extend the shelf life of fresh and minimally
processed fruits.
22

23. Sandhya, 2010
23

24. Single Film
Flexible bag, wrap films, lidding
films, etc.
e.g. PE, PP, PET, EVOH, PVC,
etc.
Packaging material for MAP
Multilayered Rigid or Semi rigid
Thermoforming-Tray, cup and Dish
e.g.
1. PET/PE
2. PS/EVOH/PE
3. PA/PE
Films are usually coated on the inside of the pack with an antifogging agent,
typically a silicon material, to disperse droplets of condensed moisture and
permit the food to be visible. Film material must be transparent, provide
good mechanical properties and good gas and vapour barrier properties.
24

25. • Use of active scavengers or emitters to control O2
and CO2 moisture and ethylene
Active MAP
• It is achieved by respiration of fruits and vegetables
and gas transmission rates of the packaging film
Passive MAP
• Gas flushing of modified gases composition during
packaging
Gas Flushing
• Remove internal gases of packages
Vacuum
Techniques of modifying gas composition in MAP
25

26. • In this system oxygen absorber, carbon dioxide scavenger and ethylene
absorber added into the packages.
• Active MAP is called as CAP(Controlled Atmospheric Packaging).
Active MAP
26

27. • CAP/ Active MAP -
• CAP involves modifying the atmospheric gas composition and control
the gas composition by active additives which are added in food
package internally to extend shelf life.
• It involves control of gas composition throughout by active
additives.
• 2 or more active compounds added in packages as per type of food.
27

28. Gas composition is altered due to the combined effect of product
respiration and permeability of the packaging film. Only respiratory
food are packed in passive MAP for example fruits.
Passive MAP
28

29. 29

30. • Equilibrium modified atmosphere packaging or EMAP -
Passive MAP can also be called as EMAP.
It is used primarily for fruits and vegetables.
Either the package flushed with required gas mix or the produce is
sealed within the pack with no modification to the atmosphere.
The type of packaging film selected is based on the film O2 and CO2
transmission rate which is required to obtain a desirable equilibrium
modified atmosphere.
EMAP means
O2 transmission rate of the packaging film = O2 consumption of the
packaged commodity
30

31. • It consists of an inert gas such as nitrogen, carbon dioxide or exotic
gases such as argon or helium which is injected in the package and
remove internal normal gases from the package.
Gas Flush Packaging/ Gas exchange preservation (GEP)
31

32. Packaging by removal of internal gases from the package and sealed.
It reduce the atmospheric oxygen which reduce the aerobic bacteria and
fungi.
Reduces oxidative changes.
Mainly used for storage of dry foods for long times like cereals nuts
spices etc. and also for short term storage of fresh foods such as fruits
and vegetables.
Vacuum Packaging
32

33. 1. In batch process:
A) Chamber Machine: Pre-formed bags are filled, pack load into machine,
chamber close, evacuated by vacuum, gas flushed and modifying gases and heat
sealed in a microprocessor controlled programmed sequence.
B) Snorkel Machine: Without chamber, used for pre-formed bags, bags filled and
hold on machine, the gas flushed and snorkel withdraw and bag sealed.
Machines of MAP
33

34. 2. In continuous operation :
Form Fill Thermoforming Machine –
The food is packaged in 3 basic methods
1. Semi-rigid thermoformed trays covered with film that has the required permeability.
2. Pillow pouches.
3. Horizontal form-fill-seal.
34

35. • For fruits, atmospheres should be as low as possible in oxygen and as
high as possible in CO2 and Nitrogen without causing the pack to
collapse and no change in flavour of the product.
• MAP system can be utilized in both respiratory foods (fruits,
vegetable, meat, fish, etc.) and non-respiratory foods (processed foods
like bakery products, coffee, snack foods, etc.) as an effective
preservation technique.
Application of MAP
35

36. Case Studies
36

37. Case Study- 1
37
Litchi fruits were harvested during the early season, were dipped for 2 min at 8 ◦C in postharvest
treatment like EDTA and then were packed in three types of bioriented polypropylene
packaging: (1) BOPP-1, (2) BOPP-2 and (3) BOPP-3, heat-sealed to modify the atmosphere
around the fruit and placed in commercial cardboard cartons. After treatment, fruit were held at
2 ◦C, 95% RH for 34 days to simulate refrigerated sea shipment conditions and thereafter, at
market shelf conditions of 14 ◦C for 2 days. Standard commercial SO2 fumigation was included
as a comparative control.

38. 38

39. 39
Conclusion-
MA created (17% O2 and 6% CO2) inside the BOPP-3 and the high RH around the
fruit minimized the rate of transpiration, preventing weight loss and deterioration of
fruit quality and retained colour and excellent eating qualities during long-term
storage. The BOPP-3 packaging can be recommended as a safe, cost-effective
alternative for extending the storage life of litchi cv. Mauritius during sea shipment.

40. Case Study- 2
40
A MAP system for pineapple and mango was developed to increase shelf life of the
fruits. Sample preparation consisted of hand-peeling, dicing, blanching, dipping in
ascorbic acid and packaging. The treatments were: gas mixture (4% O2 , 10% CO2 and
86% N2); vacuum packaging; 100% oxygen, and control.

41. 41

42. • c
42
Conclusion-
MAP with gas mixture (4% O2, 10% CO2 and 86% N2) could be used as a technology
to extend the shelf life of mango and pineapple.

43. Case Study- 3
43
Red guavas were selected, washed, sanitized (treated with 3% active chlorine), cut into halves,
peel and seeds removed and cut fruits were soaked in sucrose solution. The osmotically
dehydrated guavas were packed in PET containers to promote a passive modification of the
atmosphere around the product. These samples were named O.D. MAP (modified atmosphere
packaging).
Fresh guavas, peeled and cut packed in PET containers were used as control. The PVC film was
perforated (7 holes of 0.7 mm diameter) to maintain the atmospheric composition of air inside the
package. These samples were named FRESH MAP and FRESH AIR. These all fruits were stored
at 5 ◦C for 24 days.

44. 44

45. Conclusion-
The combination of storage temperature, MAP and the osmotic
dehydration process maintained the quality of guava fruits during the 24
days of storage. MAP had a strong influence on the preservation of
guava color and avoided product weight loss during storage and also
improved the microbiological fruit stability.
45

46. 46
Case Study- 4
Mangoes were sealed in LDPE bags and stored at 13◦ C and 94% RH. The effect of potassium
permanganate impregnated bricks as ethylene scavengers and activated granular charcoal as
carbon dioxide scavengers on extending the storage life of mango was examined.

47. 47

48. 48
Conclusion-
The fruits packaged with scavengers had lower percent weight loss and minimum
changes in physicochemical properties compared with the fruits packaged without
scavengers. Therefore, packaging in 0.05mm LDPE bags of 1:1 surface area to
weight ratio (cm2g–1) with 50ml of saturated potassium permanganate absorbed onto
suitable porous matrices and 2g of activated granular charcoal could be recommended
to increase storage life at 13°C.

49. 49
Case Study- 5
Apples (‘Golden Delicious’) were peeled and cut into slices, dipped for 2 min in 0.5%
ascorbic acid + 1% citric acid solution. Half of the slices were not dipped and served as
undipped controls. All samples were packed and sealed in polypropylene bowls. The
following atmosphere compositions were used: air (A); 99% N2, 1% O2 (B); 90% N2, 5% CO2,
5% O2 (C); 65% N2O, 25% Ar, 5% O2, 5% CO2 (D); 80% Ar, 20% CO2 (E). Analyses were
carried out after 1, 4, 8 and 11 days of refrigerated storage at 4°C.

50. 50

51. 51
Conclusion-
Various combinations of gases like O2, CO2, N2, Ar and N2O were effective in
maintaining firmness and shelf-life. 80% Ar and 20% CO2 combination was most
effective.

52. 52
Case Study- 6
The influence of two different packaging systems (biodegradable packaging and
traditional packaging) on quality loss of ‘Black Star’ sweet cherries. The fruits were
packed in two different baskets, sealed with two distinct films. The packaging systems
were: 1. Polylactic acid (PLA) basket thermo-sealed with biodegradable film (Mater-
Bi®); 2. Polypropylene basket thermo-sealed with polypropylene film (control).

53. 53

54. 54
Conclusion-
Cherries are suitable to MAP and good results are usually obtained with traditional
packaging associated with MA. It was found that biodegradable polymers are suitable
as a packaging material for storage of cherries.

55. A strong preservation of fruit quality and nutritional value is
demonstrated by MA packaging and storage with a lowering of O2 and
enhancement of CO2 concentrations. This results in –
Better quality after storage.
A longer storage period.
A longer shelf-life after storage.
A higher nutritive value after storage.
A more environmental friendly storage (no postharvest chemical
treatments are needed).
Conclusion
55

56. 56