Effect of Air Temperature on the Drying Kinetics of Pandan Leaves (Pandanus amaryllifolius) in a Fluidized Bed Dryer

Abstract

Pandan leaves are usually used when cooking to enhance aroma. Fresh pandan leaves are easy to rot because of the high water content. Drying is a very important method for preserving natural materials. The choice of drying parameters and the proper drying method is very important in order to produce quality dried leaves without removing the distinctive aroma and color. Drying of pandan leaves was usually conducted using conventional drying method. However there are some drawbacks especially on the loss of nutrients. Therefore, the purpose of this study was to examine the effect of drying temperature and drying method on the kinetics of pandan leaves drying. The drying parameters tested include hot air temperature (40-80 °C) and drying method (fluidized bed, oven). The results showed that the higher the temperature, the drying rate also increased. Drying pandan leaves in a fluidized bed dryer was faster than drying in oven due to the good contact between the hot air and the samples in a fluidized bed dryer. The drying kinetics of pandan leaves were represented in two types of curves, namely the moisture content curve with respect to drying time and the drying rate curve versus moisture content. Drying of pandan leaves in a fluidized bed dryer occured very fast and no initial and constant periods were observed. Page model was found to be the most suitable model to represent the kinetics of drying pandan leaves in a fluidized bed dryer.