Forms of Heat Transfer

Cooking can be defined in a general way as the transformation of raw foods into something different. Most often, we transform foods by heating them—by transferring energy from a heat source into the foods, so that the food molecules move faster and faster, collide harder and harder, and react to form new structures and flavors. Our various cooking methods—boiling, broiling, baking, frying, and so on—achieve their various effects by employing very different materials as the medium through which the heat moves, and by drawing on different forms of heat transfer. There are three ways to transfer heat, and an acquaintance with them will help us understand how particular cooking techniques affect foods the way they do.