Fruit Preservation Information For Competitive Exams

 Fruit Preservation 

The art and science of keeping fruits for longer time without detoriation in quality.

Nicolas Apart Is  Father Of Food Preservation Because Of His Successful Work On Preservation Of Food In Glass Containers In 1809.

Principle of preservation:
1.Canning:-

• Fruits can be processed at a temperature of 100 °C.
• Vegetable can be processed at temperature of 115-121 °C.

2 Pasteurization:-

• Heating of fruits and vegetable juice at 85-90 °C for 30 minutes.
  It kills only harmful microbes.

3. Sterilization:-

• Heating of fruits and acidic vegetables above 100 °C
  and non acidic vegetables require 116°C for 30 minutes.
• It kills both beneficial and harmful microbes.

4. Freezing:-

• Cooler storage:- 15 °C
• Refrigeration or chilling: 0-5°C

5.Cryo preservation:-

• Preserve in liquid nitrogen at -196 °C.

6.Drying:-

• Removal of moisture by applying heat is called drying eg. Raisins (Kismis).

7.Preservation through osmosis:

• High concentration of sugar:  Jam (68 % sugar), Agra ka petha.
• Salt preservation: Salt concentration 15-25 % act as preservatives e.g. in pickles(15%).

8.Preservation by chemicals:

• KMS (Potassium Meta bi Sulphite): @ 350-500 ppm or 0.05%.
• Sulphur di oxide (SO₂) is responsible for preservation.It used against colorless fruit juices/pulp.
• Sodium benzoate: @ 700 ppm/0.07%.
• Benzoic acid is responsible for preservation
  Used in colored fruit product eg. Tomato products.

9. Fermentation:

• Grape wine (alcohol 7-20%) is oldest example of fermented beverage.

10. Asepsis:- Prevent entry of microbes.

11. Oxidation :-

• can be checked by antioxidants (Ascorbic acid/ Vit.C)

12. Blanching:-

• Keeping Vegetables In Boiling Water For 2-5 Minutes Followed By Cooling.
• It Is A Thermal Process Used Mostly For Vegetables Prior To Freezing, Drying Or Canning.
• It Is Carried Out At 100°C For 2-5 Minutes.
• Blanching also inactivates enzymes.
• Lye peeling- It is the peeling of fruits (Peaches, Apricots, Sweet Oranges,Mandarin, Oranges) and vegetables (Carrot, Sweet Potatoes) in 1-2% boiling caustic soda solution for 0.5 to 2 minutes.

13.Anaerobic conditions:-

• Carbonation- Replacing the O₂ by CO_2.
• Fruit juice- Evacuating the sealed container.
• Pickles- use of oils from top of the food.

15.Anti-oxidant:-

• Are used to protect the food a deterioration caused by exposure to the air.
• Tocopherols: Animal fat
• Ascorbic acid: Fruit juices, Citrus oil, Wine, Bears.
• Lactic acid: Processed fruits and vegetables, Canned fruits.
• Phosphoric acid: Vegetable oils, Animal fat and cola drinks.

Fruit Preservation Information