Dehydration Characteristics and Mathematical Modeling of Thyme Leaves using the Microwave Process
Thyme leaves (Thymus vulgaris) with 50 g weight and 83.7% humidity on wet basis were dried in a laboratory scale microwave dryer using six different microwave power levels ranging between 200 to 700 W. The effect of drying power microwave on the coefficients of the best moisture ratio model was determined by non-linear regression method. Results from the mathematical modeling showed that the Midilli et al. model gave the best fit to describe the drying curve of thyme. In addition, the effective diffusivities of thyme under microwave drying were obtained from 2.94×10-7 to 7.38×10-7 m2/s. Also, the activation energy for the moisture diffusion was found to be 16.471 W/g.
