Microwave intermittent drying enhances drying kinetics of banana slices

摘要

Microwave intermittent drying kinetics of banana slices were investigated under different power levels (250, 400, 550 and 700W), sample thickness (3, 6, 9 and 12mm), heating time (11, 14, 17 and 20s) and intermittent time (50, 60, 70 and 80s) during each cycle. Results indicated that all the four factors had significant influence on the drying kinetics, whereas microwave power gave the most significant effect, followed by heating/intermittent time and sample thickness. Drying rate curves illustrated that the drying process of banana slices contained the increasing rate period. Moisture effective diffusivity was advanced with the growth of power level, thickness and heating time. The whole drying time was added with the increase of the intermittent time. When the drying parameters of banana slices changed under the conditions, the moisture effective diffusion coefficient varied from 2.10×10~(-10) to 7.83×10~(-9) m~2·s~(-1).