Thin-Layer Drying Characteristics of Microwave-Dried Radix Eremut (Eremurus Spectabilis)

The drying characteristics of radix eremut (Eremurus spectabilis) were investigated using microwave drying method. The drying curves of radix eremut locate in the falling rate regime and time required for drying reduced by raising microwave powers ranging from 160 to 640 W. The experimentally obtained data were fitted to six models. The most accurate models for determining the thin layer drying characteristic of radix eremut were determined to be the Midilli and Page models as the best. Effective moisture diffusion coefficients (Deff) were computed utilizing Fick's second law equation and the values of Deff found to be in range of 2.300 x 10-9 to 1.690 x 10-8 m2.s-1. Revised Arrhenius equation was implemented to identify the activation energy and its value was calculated as 148.82 W.g-1. The energy efficiency raised with raising microwave power and moisture ratio.