The influence of different drying temperatures and drying loads on the drying characteristics of coarse coconut palm sap sugar were investigated in this study. The granulated coconut palm sap sugars were dried using an air-oven dryer at three temperature variations (60, 70, 80 o C) and three different drying loads of 5, 10, and 15 kg. The drying profile of the coarse coconut palm sap sugar was determined by monitoring moisture loss over the drying period. The result showed that the moisture removal rate increased with the drying temperature. However, increasing the drying load from 10 to 15 kg did not significantly affect the drying rate at all temperature variations, resulting in the highest drying efficiency achieved at the highest drying temperature of 15 kg. Furthermore, the predicted moisture content calculated using the obtained drying rate constant value showed a high correlation with the reference value denoted by the R 2 over 0.95 for all experimental conditions. The results have demonstrated that different drying approaches may affect the drying period of coconut palm sugar using a simple air-oven dryer.

Heat and mass transfer occurred simultaneously during the drying process. Therefore, the drying rate of coconut palm sugar was evaluated by analyzing heat and mass transfer simultaneously using the Runge-Kutta method. In this study, three different temperatures and three various drying loads were carried out to develop a prediction model of moisture content by determining the constant drying rate value. The result showed that the drying rate decreased significantly at the drying temperature of 80 o C according to the drying load, ranging from 1.36 to 0.32 h -1 . However, the load of the dryer only causes a slight decrease in drying rate at 60 o C. Furthermore, the developed model based on the simultaneous heat and mass transfer analysis can predict the moisture content of the sample effectively, with the value of correlation coefficient (R 2 ) over 0.97.