Protective foods Vitamins and minerals Fibers

1. Post-harvest physiological approaches
for preservation of Fruits and
Vegetables
Presented by
B. ANANDHI
ID No. 2015018010
III B. Sc., Agriculture

2. Importance of fruits and vegetables
• Protective foods
• Vitamins and minerals
• Fibers

3. Quality Components of Fresh Fruits
and Vegetables
• Appearance
• Texture
• Flavor
• Nutrition
• Safety

4. Morpho - anatomical basis for
perishability of fruits and vegetables
• Fruit wall
• Surface area to volume ratio
• Cuticle
• Stomata
• Hairs and spines
• Lenticels
• Laticifers

5. Post-harvest
• The post-harvest sector includes all points in
the value chain from production in the field to the
food being placed on a plate for consumption.

7. Post-harvest loses
Primary causes
Biological and
Microbiological
Chemical and biochemical
Mechanical
Physical
Physiological
Psychological
Secondary causes
Respiration
Ethylene production
Compositional changes
Growth and development
Transpiration
Physiological breakdown

8. Why preservation?
• Fresh fruits and vegetables are perishable
• 20 – 50 % loss

9. Post-harvest
physiological
process
Respiration
Transpiration
Ethylene
production
Senescence

10. Post-harvest
morphological
changes
Sprouting
Elongation
and
curvature
Seed
germination
Rooting

11. Physiological approaches for preservation
• Temperature control
Respiration

12. Cooling
• Pre cooling
• Room cooling - Potato, Onion, Garlic
• Forced cooling- Tomatoes, Asparagus

13. • Hydro cooling
• Top or liquid icing –broccoli and sweet corn
• Vaccum cooling

14. Reduced oxygen availability

15. Transpiration control
• RH management
• Adding moisture
• Air regulation
• Polythene liners
• Curing
• Waxing

16. Ethylene management
• Ventilation
• Avoid mixing
• 1 - Methyl cycloprene
• Cycloheximide
• Benzothiadiazole
• Silver thiosulfate

17. Delaying senescence
• Heat treatment
• GA3
• Pseudomonas syringae
• Candida oleophila
• Sulphur dioxide

18. Preservation of fresh cut fruits and
vegetables
Color preservation
• Browning
• White blush in carrots
• Yellowing or degreening

19. Anti browning agents
• Acidulants
• Reducing agents
• Chelating agents
• Complexing agents
• Enzyme inhibitors
• Sodium chloride
• Calcium treatments
• Honey

20. Edible coating
Coated with chitosan Ag nanocomposites

21. Modified atmospheric packaging
• Modifying the composition of internal
atmosphere of package.
• 2 -5 % O2 and 8- 12% CO2

22. Irradiation
• Ionizing radiation