Predição de modelos sobre a cinética de secagem de folhas de Ziziphus joazeiro Mart

Abstract

This research aimed to study experimentally the kinetics of drying leaves of Ziziphus joazeiro Mart. in thin layer in an oven with forced air using the temperatures of 40, 50 and 60 °C and the air velocity of 0.5, 1.0 and 1.5 m s -1 according to the factorial design (2 2 + 3) and subsequent adjustment of the experimental data in different models, and we select the one that best represents the phenomenon of drying. We determined the initial water content of the leaves by the standard oven method, in triplicates. For each drying treatment, we used approximately 150g of leaves. For adjustment, we used the non-linear regression analysis, through the Quasi-Newton method, using the software Statistica 5.0 ®, in which the parameter values of the equations were determined for the temperature and velocity of the drying air. The equation that best represented the drying process of the Ziziphus joazeiro Mart. for the temperature range of 40-60 °C was the Midilli equation. The results showed that there is a greater reduction in drying time with increasing temperature.