DRYING CHARACTERISTICS OF HAWTHORN FRUITS IN A CONVECTIVE HOT-AIR DRYER

In this study, the drying characteristics of hawthorn fruits were examined in a laboratory scale hot-air dryer at an air velocity of 0.8 m/s and air temperature in the range of 50-70C. Moisture transfer from the test samples was described by applying the Fick's diffusion model, and the effective diffusivity was calculated. The temperature dependence of the effective diffusivity was described by the Arrhenius-type relationship. The experimental drying data of hawthorn fruits were used to fit Page, Logarithmic, Approximation of diffusion, Two-term and Midilli et al. models, and the statistical validity of models tested were determined by nonlinear regression analysis. Estimations by the Midilli et al. model were in good agreement with the experimental data obtained. PRACTICAL APPLICATIONS Hawthorn fruit is known as a medicinal plant throughout the world. For hawthorn extract and powder products, drying is necessary. This work evaluates the drying conditions and presents a mathematical model for hot-air drying of hawthorn fruits. With these results, drying of hawthorn can be carried out in industrial convective dryers.