Getting to the Heart of Heat Transfer

Of the significant transport processes—heat, mass, and momentum—heat transfer is often of greatest interest to food processors. Thermal processing—heating foods to sterilize them—speaks for itself. Other examples include dehydration, freezing, cooking, evaporation, frying, freeze-drying, and cooling. In each of these, transfer of energy into or out of food determines rate, costs, and quality.

Most people have an intuitive understanding of the law of thermodynamics that says that energy moves from…