INFRARED DRYING KINETICS AND QUALITY CHARACTERISTICS OF CARROT SLICES

Abstract

The effect of different infrared powers on the drying kinetics of carrot slices was investigated. The carrot slices were dried at 62, 74, 88, 104 and 125 W infrared powers and constant slice thickness of 0.5 cm. The results showed that the infrared power has a significant effect on the drying and quality characteristics such as rehydration and color. The whole drying process occurred within the falling rate period. Six thin-layer drying models were fitted to the experimental data. The Midilli et al. model was best fitted to the experimental data. Fick's law of diffusion was used to determine the effective moisture diffusivity, which varied between 2.45 x 10(-9) and 7.38 x 10(-9) m(2)/s. Activation energy was estimated by a modified Arrhenius type equation as 4.247 kW/kg.