Drying Kinetics and Chemical Properties of Mango

Abstract

Four mango fruit varieties of average slice thickness 0.6 cm and slice area 10 cm 2 were dried using a mechanical dryer at variedtemperatures, 55°C, 65°C, and 75°C. In general, the moisture content (MC) for all samples analyzed decreased with increasingdrying time. Palmer and Haden varieties recorded the lowest MCs of 8.7% (w.b.) and 9.3% (w.b.), respectively, when dried for14 h at 65°C. Palmer variety with the highest initial MC of 87.2% (w.b.) recorded a low final MC of 8.7% (w.b.) when dried for14 h at 55°C. Moisture ratio decreased from 1.00 to 0.13, 1.00 to 0.12, 1.00 to 0.12, and 1.00 to 0.10 at 55°C for Kent, Keitt,Haden, and Palmer varieties, respectively. Kent, Keitt, Haden, and Palmer varieties recorded effective moisture diffusivityvalues of 5:90 × 10–7, 6:40 × 10−7, 6:57 × 10−7, and 7:33 × 10−7 m 2 /s, respectively. Vitamin C content of 158.34 mg/100 grecorded for Palmer was highest compared to the other varieties. Activation energy values of samples analyzed were between19.90 and 25.50 kJ/mol for the drying temperature range. The activation energy recorded by Haden variety was highest compared to the rest. Also, twelve mathematical models were analyzed in predicting the moisture ratio of mango fruit slices during thin layer drying. The results showed that the Midilli, Page, Wang and Singh, and Logarithmic models exhibited supremacy in predicting drying behavior compared to the other eight models.