AQA GCSE Food Preparation and Nutrition: Student Book

Why is it important in cooking? • This is why if you put a metal spoon into a pan of boiling water, or use a metal spoon instead of a wooden spoon to stir a Béchamel sauce, it will gradually heat up until it is too hot for you to hold the spoon handle. Spoon in hot coffee getting hotter to the end of the spoon • This is why we use metal pans and baking tins to cook and bake food quickly and efficiently. • It is important for a pan to have a well-made, flat and strong base so that it stays in close contact with the hob and allows the heat energy to conduct through it evenly. • Poor quality pans may warp (buckle and bend) because the base is too thin, which means it will not transfer the heat evenly. Heat insulators are used in a variety of ways to prevent us from burning ourselves when we are cooking, for example: • Pan handles are often made of plastic or wood so they are comfortable to hold. • Some pans have metal handles that are hollow inside, and the air they contain prevents the metal from becoming too hot, as air is a heat insulator. • Using wooden spoons to stir a sauce. • Whatever material the handle is made from, it is important to remember to position pan handles away from direct heat on the hob, as any material will eventually become too hot to hold safely if it is heated. • Insulated pan stands made from wood, ceramics or metal should be used to stand a hot pan or baking tin on, rather than the worktop, which might blister with intense heat. A blistered worktop caused by a hot pan ©www.plastic-surgeon.co.uk Section 2: Food Science Chapter 3 Cooking of food and heat transfer 86