Modeling of Microwave Drying of Fruits

Abstract

Heat and mass transfer in foods during microwave drying was studied experimentally and theoretically through mathematical modeling. The food was considered as a system with physical properties that can vary with composition, structure, and temperature. Inner heat generation due to transformation of the electromagnetic energy was accounted for by using the approximation of Lambert's law. Two successive stages were considered: material heating that was followed by liquid evaporation. The coupled system of partial differential equations was coded in Matlab 6.5 (Mathworks, Natick, MA) and used to simulate the experimental runs of pear slices drying in a household microwave oven. Predicted temperature histories at the surface and center of the slab as well as mass loss during drying were in good agreement with experimental results.