DETERMINATION OF SUITABLE THIN LAYER MODEL FOR AIR DRYING OF MANGO SLICES (Mangifera indica L.) AT DIFFERENT AIR TEMPERATURES AND VELOCITIES

An air dryer was used for thin layer drying process of green and half-ripe mango, and moisture ratios at any drying time were compared by 10 models (Newton, Page, Henderson and Pabis, modified Henderson and Pabis, logarithmic, two-term, two-term exponential, Wang and Singh, Verma et al. and Midilli and Kucuk). The Midilli and Kucuk model satisfactorily described the drying behavior of mango slices at different maturity stages with highest R2 values and lowest chi 2. Parameters kappa, n and b for the Midilli and Kucuk model were significantly different (P < 0.05) for both maturity stages and were affected by air velocity and temperature. Parameter kappa for green mango was found to be the least temperature sensitive. Parameter n for green mango was found to be the most temperature sensitive. Temperature dependence of parameter b for both maturity stages did not follow a relation type Arrhenius. PRACTICAL APPLICATIONS This work is intended to provide a significant tool to predict the moisture content of the green and half-ripe mango slices at any time of drying process, establish the air drying conditions in order to achieve given moisture content of mango slices, and optimize the design of thin layer drying process.