Physical Parameters and Kinetic Modeling of Fix and Fluid Bed Drying of Terebinth Seeds

The effect of different drying conditions on the effective moisture diffusivity, activation energy, specific energy, shrinkage, rupture force and energy, and color of terebinth was studied. Experiments were conducted at five levels of hot air velocity (0.8, 1.35, 2.08, 3.35 and 4.43m/s) and five temperature levels (40, 50, 60, 70 and 80C). The obtained effective moisture diffusivity of terebinth ranged between 1.1x10-10 and 1.26x10-9m2/s and the calculated activation energy of the samples was 49.99-51.22kJ/mol. Results showed that the Logestic model with R2=0.9994, 2=0.00177 and RMSE=0.0318 had the best performance in moisture prediction. Maximum shrinkage during drying was calculated to be 72.2% at air temperature of 80C and air velocity of 4.43m/s. Maximum rupture force and energy for dried terebinth were calculated to be 135.6N and 2,509.6N center dot mm, respectively. Most color (RGB) changes were obtained at air temperature of 80C and air velocity of 4.43m/s. Practical Applications Advantages of fluid bed drying include short processing time, high mass transfer coefficients, low energy consumption and high quality. As heat and mass transfer and quality changes during drying of terebinth with fluid bed method are not described in the literature, it is of importance to gather such data and compare them to find the optimum point of the process. The data clearly proved that in addition to short processing time, the terebinth temperature and moisture content can easily be controlled, and thus, monitoring of terebinth characteristics such as shrinkage, color and mechanical properties, and energy utilization during drying process can be achieved. The models developed for thermal, physical and mechanical characteristics of terebinth fruit can be used to predict more accurately the drying process using a computer and to simulate the storage of terebinth fruit.