Characteristics of osmotic-vacuum microwave drying of tilapia fillets and its drying kinetics

In order to obtain the characteristics of tilapia fillets under osmosis dehydration vacuum-microwave drying conditions, the moisture content and drying rate of fish fillet were carried out during drying process.The effect of different microwave gap ratio, power density and vacuum degree on drying characteristic of fish fillet were determined and the drying kinetics model of osmosis dehydration vacuum-microwave drying was set up.The results showed that the microwave gap ratio, power density and vacuum degree had greater influences on dry characteristics of tilapia fillets. The drying rate was increased with increasing of power density and vacuum degree, and improved the microwave gap ratio appropriately was conductive to speed up the drying process. In addition, the whole drying process was divided into two stages with different conditions, including the accelerated drying and falling rate drying. The time of accelerated drying was short and the main process was falling rate drying. The drying kinetics met Midilli model and it was suitable for describing osmosis dehydration vacuum-microwave drying process of tilapia fillet ( R²= 0.9873) . The results provide a new theory and technical guidance for tilapia processing and production.