Thin-Layer Drying Kinetics of Strawberry Fruit Leather

The effects of air temperature and sample thickness on drying kinetics of strawberry fruit leather were investigated. The mathematical modeling was performed by using three thin-layer drying models. The independent variables were sample thickness (1.8, 2.7, and 3.6 mm) and air temperature (50C, 60C, 70C, and 80C). Drying took place in the falling rate period. The values of effective moisture diffusivity (Deff) varied from 2.40 10-9 to 12.1 10-9 m2 s-1 depending on drying conditions. The values of activation energy (Ea) were 35.57, 33.14, and 30.46 kJ mol-1 for 1.8, 2.7, and 3.6 mm sample thickness, respectively. The two-term exponential model was found to satisfactorily describe the thin-layer drying kinetics of strawberry leather.