Drying characteristics of walnut (Juglans regia L.) during convection drying
More details
Hide details
Department of Agricultural Technical Engineering, Faculty of Agricultural Engineering, Abureyhan University College, University of Tehran, P.O.Box 11365-4117-Tehran, Iran
Int. Agrophys. 2009, 23(2): 129–135
Drying characteristics of walnut were determined experimentally as a function of temperature, air velocity and variety (Serr, Pedro, Z67, K82). Four different drying models were fitted to the experimental data to select a suitable mathematical form of the drying curve. Experiments were performed at air temperatures of 32 and 43°C and two air velocities of 1 and 3 m s-1 at each temperature. Of the drying models tested, the Page model was selected as the best mathematical model based on the values of R2, 2 and RMSE. Drying time and Page model constants were significantly dependent on the variables studied. Correlations of the Page model constant, k and m, the effective moisture diffusivity of walnuts and the drying time with the variables were determined. The effective moisture diffusivity of walnuts varied from 3.54×10-7 to 9.92×10-7 m2 s-1.