Question

Write the different methods of food preservation.

Answer 1

Different methods of food preservation are-

1. Storage and Packing: where water is removed from foodstuff preventing the growth of microbes. Examples- vegetables, dry fruits, pulses, spices etc.
2. Preservation by chemicals- Sodium benzoate, sodium metabisulphite etc. are used as preservatives to store pickles, jam, squashes etc. They prevent the attack of the microbes.
3. Preservation by Common Salt- Adding of common salt helps to preserve meat, fish for ages.
4. Preservation by sugar- sugar is added to jam, jellies, squashes which reduces the moisture content which inhibits the growth of bacteria which spoil food.
5. Preservation of oil and vinegar- Use of oil and vinegar prevents spoilage of pickles because bacteria cannot live in such an environment. Vegetables, fruits, fish and meat are often preserved by this method.
6. Pasteurization- Pasteurization is a process in which the liquid substance is heated to a temperature of 70oC for 15 to 30 Seconds and the suddenly chilled and stored. It is used to preserve wine, milk etc.
7. Irradiation- High energy gamma rays or X-rays are used to preserve foods.
8. Vacuum drying- Milk is converted into milk powder by this process where moisture is removed.
9. Proper storage and packing- dry fruits, vegetables are properly stored and sealed in air-tight packets.
10. Hot and cold treatment- We can boil food and store or we can refrigerate foods at very low temperature. Because microbes die at very high or low temperature.