Modeling of the combination of vacuum and infrared drying of kiwifruit slices

The effects of different drying condition on the drying characteristics of kiwifruit slices were studied and the combined drying kinetics mathematical model was established for kiwifruit slices. The results showed that combined drying process of kiwifruit slices could be divided into three stages: increasing rate,constant rate and falling rate stage. Constant rate drying period was the primary period in the drying process,which had highest drying rate and largest evaporation amount. The value of moisture effective diffusivity ranged from 3.91 × 10- 9to7.79 × 10- 9,which increased with the radiant power,loading capacity,and vacuum degree increased.A thin layer mathematical model of kiwi slices was established and the model equation was in accordance with Page. This research provided the technique basis for the application of drying kiwifruit.