ABSTRACT

Energy efficiency and food quality are two key issues in food drying. In intermittent drying, the moisture diffuses towards the surface during the tempering period, which makes water available on food surface and thus increases the subsequent drying rate. Consequently, intermittent drying can improve energy efficiency and food quality. Mathematical modelling can provide detailed understanding of heat and mass transfer that takes place during drying. Moreover, models can provide dynamic profiles of temperature and moisture distribution and redistribution during intermittent drying, which is difficult to investigate experimentally. This chapter provides an overview of mathematical modelling of intermittent and time-dependent drying, including intermittency of heat sources such as microwave and infrared. The approaches of modelling of intermittent drying and their advantages and disadvantages are also discussed. Further, the reaction engineering approaches (REA) on intermittent drying modelling are presented and discussed. Finally, the solution techniques for the models are presented.