Simulation of mass transfer kinetics of microwave drying of fish paste

Fish pastes are commonly consumed in Asia and it is made from ground fish meat mixed with flour, water, salt and spices.The study investigatedinfluence of microwave poweronmass transfer kinetics of fish paste drying. The moisture content and product temperatures were recorded in order to obtain the effective diffusivity that governs the mass transfer process. Drying rates were observed to increase with increment inmicrowave power from 300 to 900W. The drop in moisture ratios followed exponential decaying trend typical for food products. COMSOL Mutiphysicswas used to simulate the mass transfer process in 2D geometry. The effective diffusivities were incorporated into the Fick’ slawmodeland able to provide good prediction of the moisture distribution within the fish paste sample. Effective diffusivities were determined and fall within the range as reported in published literatures (10−8 – 10−12 m2/s). Simulation showed that middle section of the hot air dried sample registered higher moisture ratio (MR = 0.11)than the microwave dried samples (MR=1.3E-4 and below). Microwave is therefore recommended as one of the drying options to the food industry due to faster drying rate and more efficient heating.