Drying Characteristics of Sweet Potato

The drying test of sweet potato has been done at the air conditions of 40,50,60, and 75 ℃, in order to investigate the drying characteristics. In this study, three types of drying periods, the constant rate drying period, the first falling rate drying period, and the second falling rate drying period, was found during drying. With regards to this, three drying equations, the modified constant rate drying equation, the first falling rate drying equation, and the second falling rate drying equation were applied to the observed drying curve (moisture ratio vs. time) for each drying period respectively. Result shows that the calculated values have a good agreement with the data. Furthermore, it revealed that drying constants in first and second falling rate drying period have Arrhenius type temperature dependency