DETERMINATION OF SUITABLE THIN LAYER MODEL FOR AIR DRYING OF COROBA SLICES (ATTALEA MARIPA) AT DIFFERENT AIR TEMPERATURES AND VELOCITIES

ABSTRACT An air dryer was used for thin layer drying process of coroba, and moisture ratio at any drying time was compared by eight models (Newton, Page, Henderson and Pabis, logarithmic, two-term, two-term exponential, Verma et al., and Midilli and Kucuk). The effect of drying air temperature (71, 82 and 93C) and velocity (0.82, 1.00 and 1.18 m/s) on the coefficients of the best suited moisture ratio model was determined by multiple regression method. Coefficient of determination (R2) and reduced chi-square (χ2) were used for the determination of the best suitable model. Among the mathematical models investigated, the Midilli and Kucuk, and logarithmic models satisfactorily described the drying behavior of coroba slices with highest R2 values and lowest χ2. The relationships between the constants k of the Midilli and Kucuk, and logarithmic models, with the drying variables of drying air temperature and velocity, were determined. PRACTICAL APPLICATIONS As a result, this work is intended to provide a significant tool for predicting the moisture content of the product at any time of the drying process, establish the air drying conditions in order to achieve given moisture content of coroba slices and optimize the design of the drying process.