Development of a Vacuum Type Pan Evaporator for Kithul Treacle and Jaggery Production

Abstract

Kithul (Caryota urens) treacle and jaggery considered to be most important traditional sources of sweeteners. Sap of the Kithul palms is used to produce treacle and jaggery, which fetch high nutritional and export market value. In the whole traditional treacle production process, moisture removing step consumes more time, labor and energy. There is no new mechanical application for rapid removal of moisture other than traditional method. Therefore, the aim of this study was to develop a suitable device for efficient moisture removal from the sap. A simple vacuum type pan evaporator of 8 L was developed and tested at faculty of Agriculture, Rajarata University of Sri Lanka. The most salient feature of this device was, ability of controlling the inside pressure of the container to enhance the moisture evaporation under low temperature. The performance of the device was evaluated with Kithul sap over the manual method with three replicates for each process using LP gas and firewood as energy sources. When gas was used as the energy source, the average time taken for the initiation of the moisture removing, duration of moisture removing and the total process has been reduced by 41%, 37.6% and 30.6% respectively compared to the traditional method. Those values were computed as 40%, 27% and 24.5% respectively when firewood was used. The statistical comparison revealed that new method was significantly performed than that of traditional method(p<0.05) and gas was the best energy source for the new method.