Mathematical Modeling and Investigation of the Effect of Power on Effective Moisture Diffusivity and Activation Energy of Turnip Slices in Microwave Drying

Microwave (MW) drying is an energy-efficient drying method that helps maintain product longevity and quality. Microwave drying process factors are among the important issues in innovative methods of drying food and agricultural products. In this study, the effect of microwave power on moisture content, moisture ratio, drying rate, Effective Moisture Diffusivity and activation energy was investigated in the microwave drying process. For this purpose, ۳ mm thick turnip slice samples were dried at different microwave power levels (۵۵۰, ۷۷۰ and ۱۱۰۰ W). To determine the kinetic parameters and mathematically model the drying process, experimental data were fitted to various models. Among the thin layer drying models, the Midili model showed a better fit for all drying conditions at different power levels. As the microwave output power increased, the Deff values increased from ۳.۸۲۹×۱۰-۹ to ۸.۸۴۵×۱۰-۹ m۲/s. During the drying process, higher moisture release rates occur at lower activation energy levels. The values of Ea and D۰ were determined as ۲۰.۸۶۹ W/g and ۲.۰×۱۰-۸ m۲/s, respectively.

کلیدواژه ها:

activation energy ، Microwave drying ، Modelling ، Moisture diffusivity and Turnip