Drying, shrinkage and rehydration characteristics of kiwifruits during hot air and microwave drying

Hot air, microwave and hot air-microwave drying characteristics of kiwifruits (5.03 +/- 0.236 mm thick) were investigated. Drying rates, shrinkage and rehydration capacities of these drying regimes were compared. The drying took place in the falling rate drying period regardless of the drying method. Drying with microwave energy or assisting hot air drying with microwave energy resulted in increased drying rates and substantial shortening of the drying time. Shrinkage of kiwifruits during microwave drying was greater than hot air drying. Less shrinkage was observed at hot air-microwave drying. Microwave dried kiwifruit slices exhibited lower rehydration capacity and faster water absorption rate than the other drying methods studied. (C) 2001 Elsevier Science Ltd. All rights reserved.