List the methods of prevention of …

Corrosion is the process in which metals are eaten up gradually by the action of air, moisture or a chemical (such as an acid) on their surface. Rusting of iron metal is the most common form of corrosion. During the corrosion of iron, iron metal is oxidised by the oxygen of air in the presence of water (moisture) to form hydrated iron oxide called rust.

The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called rancidity. It spoils the food materials prepared in fats and oils which have been kept for a considerable time and makes them unfit for eating.

Methods to prevent rancidity:

(i) Rancidity can be prevented by adding anti-oxidants to foods containing fats and oils.

(ii) It can be prevented by packaging fat and oil containing foods in nitrogen gas.

(iii) Rancidity can be retarded by keeping food in a refrigerator.

(iv) Rancidity can be prevented by storing food in air-tight containers.

(v) Storing foods away from light can also prevent rancidity.