ABSTRACT
The heat transfer problems in biological materials either during the production stage or during handling and processing include solid – liquid interface, solid–gas interface, liquid – liquid interface and liquid–gas interface. Heating, cooling, or freezing of solids, drying or dehydration of solids either as a mass or as unit solids, and heating and cooling of liquids are the examples which may involve one or more of these interfaces. In some cases the heat transfer is also accompanied by mass transfer such as drying and dehydration.
