Moisture Sorption Isotherms of Tender Cashew Kernel at Varied Temperatures

Adsorption-desorption behaviors of tender cashew kernel were studied at different relative humidity (ERH) ranging from 0 and 100% and temperatures at 30, 40, 50 and 60°C following the static equilibriation technique using the saturated solutions of various salts. These data were analysed and fitted Guggenheim-Anderson-de Boer (GAB) sorption model. The temperature dependence of the respective coefficients revealed that the GAB model is acceptable (r² ≥ 0.994; M_RES ≤ 904) in describing the EMC-ERH relationships of the tender cashew kernel. The M₀, C and K values were in the range of 5.740-5.645, 375.538-111.550 and 0.504-0.490 for adsorption. The corresponding values for desorption are 13.274-12.935, 808.516-342.936 and 0.427-0.421. The net isosteric heats of sorption estimated from the Clausius-Clapeyron equation, decreased exponentially from 1.17 to 0.60 kJ mol-¹ with the increase in moisture content of the sample 8 % to 23% (db) for adsorption. The corresponding values were 5.75 to 0.684 kJ mol-¹ for desorption.