Analysis of heat, mass and pressure transfer in starch based food systems

A set of coupled heat, mass and pressure transfer equations proposed by Luikov (1975, Heat and mass transfer in capillary-porous bodies, Pergamon, UK) was employed to model the heat, mass and pressure transfer phenomenon in a composite food system during drying. A two-dimensional finite element model was developed to solve the coupled equations with non-linear material properties. The finite element results were validated by comparing with exact solutions. The validated finite element model was then used to predict the temperature and moisture history in hydrated composite starch systems. Comparison of predictions from the coupled and uncoupled heat and mass transfer models, which assumed that pressure is a constant, with the experimental data showed a marked difference. Simulation results indicated that predictions from the heat, mass and pressure transfer model agreed well with the available experimental data.