FOOD SCIENCE AND PROCESSING 3 (2+1)

Lesson 4 : Methods of Food Preparation

Deep fat frying

Food is totally immersed in hot oil and cooked by vigorous convection currents and cooking is uniform on all sided of the foods. Cooking can be rapidly completed in deep fat frying because the temperature used is 180-2200C. In most foods, this high temperature results in rapid drying out of the surface and the production of a hard crisp surface, brown in colour. The absorption of fat by the food increases the calorific value of the food. Fats when heated to smoking point decompose to fatty acids and glycerol followed by the decomposition of glycerol to acrolein, which causes irritation to the eyes and nose. Generally around 10% of oil is absorbed but larger amount of fat is absorbed when oils are used repeatedly. Samosa, papads, chips, muruku, pakoda, bajji and bonda are made by deep dry frying.

Advantages

• Taste is improved along with texture.
• Increases the calorific value.
• Fastest method of cooking.
• In shallow fat frying, the amount of oil consumption can be controlled.

Disadvantages

• Sometimes the food may become oily or soggy with too much absorption of oil.
• More attention is required while cooking and care should be taken to avoid accidents.
• The food becomes very expensive.
• Fried food takes long time to digest.
• Repeated use of heated oils may produce harmful substances and reduce the smoking point.