The Investigation of The Drying Kinetics of Vitis Labrusca L. Type Grape by Using Microwave Method

Abstract

Vitis labrusca L. grape (Isabella Grape) is among the grape types that are consumed frequently in the world. Dry fruits are used frequently as snacks for people who work hard and in diet especially during the recent years compared to wet fruits. In this study, the drying characteristics of Vitis labrusca L. are investigated with using different microwave power levels. Mathematical modeling of drying is studied by using the drying models frequently used in the literature. By using spherical coordinates effective moisture diffusion coefficients and activation energy are calculated. Vitis labrusca L. are dried at 20, 6 and 2 minutes with 90, 180 and 360 W power levels, respectively. The best drying model was determined as Alibas and R2, ï£ï€², and root mean square error (RMSE) values were calculated between 0.999398 - 0.999715, 0.000182 - 0.000169, 0.010589 - 0.008675 respectively. Vitis labrusca L. are generally dried in a falling- rate period. Effective moisture diffusion coefficients were calculated between 2.11×10-7 - 6.61×10-8 m2/s and the activation energy were calculated as 75.464 kW/kg. Energy consumption values were determined as 108, 64.8 ve 43.2 kJ at the microwave power levels of 90, 180 and 360 W, respectively.