Food Science Basics: Heat Transfer
The Culinary Institute of America
Cooking is the act of applying heat to foods to prepare them for eating. When foods are cooked, changes in flavor, texture, aroma, color, and nutritional content occur during the process.
There are three ways that heat is transferred to foods. Conduction is the direct transfer of heat between adjacent molecules. An example of conduction is cooking on a flattop range. Heat is transferred from the molecules of the hot range surface to the molecules of the adjacent pan bottom, then from the pan bottom to the pan sides and the food contained within the pan. The pan must be in direct contact with the range for conduction to occur.
Some materials are better conductors of heat than others. Generally, most metals are good conductors, while gases (air), liquids, and nonmetallic solids (glass, ceramic) are not. Because it relies on direct contact, conduction is a relatively slow method of heat transfer, but the slow, direct transfer of heat between adjacent molecules is what allows a food to be cooked from the outside in, resulting in a completely cooked exterior with a moist and juicy interior.
3. Induction Cooking
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