Mathematical Modeling and Drying Characteristics Investigation of Black Mulberry Dried by Microwave Method

Abstract

In this study, microwave drying characteristics of black mulberry were studied at microwave power levels of 90, 180 and 360 W. Obtained experimental drying results were applied to seven mathematical models of Aghbashloet al., Henderson and Pabis, Jena and Das, Logaritmic, Midilli and Kucuk, Page and Weibull. The best model was selected as Midilli and Kucuk based on the highest coefficient of determination (R-2) (0.994861-90 W, 0.999824-180 W, 0.998747-360 W) and the lowest chi(2)(0.000575-90 W, 0.000027-180 W, 0.000255-360 W) and Root Mean Square Error (RMSE) (0.022427-90 W, 0.004275-180 W, 0.011899-360 W) values compared to other models. According to drying times, the best drying condition was seen on 360 W power. The effective moisture diffusivity (D-eff) values were calculated using the Fick's second law's spherical coordinate approximation and were found between 4.79 x 10(-8)and 2.60 x 10(-7) m(2)/s. The activation energy (E-a) was calculated using modified form of Arrhenius equation and found as 13.15 kW/kg.