ABSTRACT

In the process of baking, heat is transferred primarily by convection from the heating medium and by radiation from oven walls to the product surface. This is followed by conduction to the geometric center. At the same time, moisture diffuses outward to the product surface. The temperature and moisture distribution within the porous structure can be predicted using appropriate diffusion equations of heat and moisture transport. In order to predict the temperature and moisture distribution in the product during baking, knowledge of the product properties is needed, including physical, thermal, and moisture transport as a function of processing conditions (Rask, 1989; Sablani et al., 1998). These properties are apparent density (or specific volume), specific heat, thermal conductivity, thermal diffusivity, and moisture diffusivity.