Food Preservation

Microorganisms spoil our food. Spoiled food gives bad smell and has bad taste and color change. So it is very necessary that we protect our food from the reactions of microorganisms this can be done by the following methods of food preservation.

Chemical Method

Salts are edible oils are the common chemicals generally used to check growth of microorganisms. Therefore they are called preservatives. We add salt or acid preservatives to pickles to prevent the attack of microbes. Sodium benzoate and sodium metasulphite are common preservatives. They are also used in jams and squashes to check their spoilage.

Preservation by common Salt

Common salt has been used to preserve meat and fish for ages. Meat and fish are covered with dry salt to check the growth of bacteria. Salting is also used to preserve amla, raw mangoes, tamarind etc.

Preservation by Sugar

Jams, jellies and squashes are preserved by sugar; sugar reduces the moisture content which inhibits the growth of bacteria which spoil food.

Preservation by Oil and Vinegar

Use of oil and vinegar prevents spoilage of pickles because bacteria cannot live in such an environment. Vegetables, fish and meat are often preserved by this method.

Heat and Cold treatments

Boiling kills many microorganisms. Similarly we can keep our food in refrigerator. Low temperature inhibits the growth of microbes.

Storage and Packing

These days’ dry fruits and even vegetables are sold in sealed air tight packets to prevent the attack of microbes.