Moisture diffusivity analysis in a microwave drying process under different operating conditions

This article deals with the kinetic analysis of the drying of sliced mushrooms (Agaricus bisporous) and apples (Golden Delicious), as representatives of vegetables and fruits, by the application of microwave. The drying experiments were carried out in monomode or multimode cavities, depending on the purpose of the study. In the former, the location of the temperature control is analyzed, and in the latter, the effect of pressure, air humidity, and temperature control. In the experiments, the mass loss was monitored over time and the drying kinetics described by means of a model, assuming effective diffusivity to be constant. The changes in the diffusion coefficient could be explained in terms of possible texture modifications of the product derived from the different conditions experienced during drying.