Influence of Infrared Drying on Some Quality Properties of Nashi Pear (Pyrus pyrifolia) Slices

Abstract

The effect of different infrared powers on drying of pear slices was investigated in an infrared dryer at 50-, 62-, 74-, and 88-W infrared powers. The infrared radiation power affects the drying kinetics and quality of food products. As the infrared power increased, the drying time decreased, and the effective diffusivity coefficient increased. Seven different thin-layer drying models were evaluated for moisture ratios using nonlinear regression analysis. The results of regression analysis indicated that the model of Aghbashlo et al. is the best to describe drying behavior with the lowest P, chi(2), RMSE and the highest R-2 values. The Fick's diffusion model was used to calculate the effective moisture diffusivity (D-eff) of pear slices. The value of D-eff varied from 9.43 x 10(-10) to 2.58 x 10(-9) m(2)/s. Activation energy was estimated by a modified Arrhenius type equation as 1.32 kW/kg.