Mathematical modelling of shrinkage effect during drying of food

Shrinkage is one of the major changes taking place during the drying process. Typically, empirical fitting through experiment data is used to find the shrinkage equation. In this paper, the shrinkage equation was developed on the basis of a simple mechanism of volume of water evaporated during drying and is not dependent on data from experiment. The shrinkage equation was put into the model of heat and mass transfer for the prediction of moisture and temperature distributions during drying. A numerical solution technique, based on the method of lines, has been used with local finite difference approximations to the drying interface. Results show that the model incorporating the effect of shrinkage is capable of describing the behaviour of moisture and temperature in food during drying.