Investigation of Drying Characteristics of Parboiled Wheat Kernel in a Halogen Lamp Dryer and Its Modelling

Abstract

In this study, the halogen drying characteristics of parboiled wheat was investigated. Drying experiments were performed at different temperatures (50, 60, 70 and 80 °C) and selected thin layer drying models were applied to drying data. The effects of drying temperature on drying rate, drying rate constant and effective diffusivity of parboiled wheat were evaluated. It was observed that the drying occurred in the falling rate period and the drying constant increased with increasing of drying temperature. Weibull distribution model among the using mathematical models was the best mathematical model representing the drying curves. Effective moisture diffusivity was calculated using the Fick’s second law and varied from 6.39´10^-11 to 2.22´10^-10 m² s^-1 over the temperature range. The temperature dependency of effective diffusion coefficient was correlated by the Arrhenius-type relationship. Activation energy (E_a) was determined as 39.667 kJ gmol^-1.