Kaffir Lime Leaves Drying Using Far Infrared-Vacuum Technique

Abstract

Objectives of this research were to study drying kinetic, specific energy consumption, color quality, effective moisture diffusivity coefficient and mathematical modeling for predicting drying kinetic of kaffir lime leaves by combined vacuum and far-infrared. Conditions of this research were conducted by initial moisture content of kaffir lime leaves was 170%d.b., drying at absolute pressure of 5 kPa and 15 kPa and temperature of 45oC and 55oC, final moisture content of kaffir lime leaves was 5%d.b. Results shown that drying time and specific energy consumption were decreased whereas drying rate was increased by decreasing of absolute pressure and increasing of drying temperature. Anyway, color difference was decreased by drying at low temperature. Therefore, drying condition at absolute pressure of 5 kPa and temperature of 45oC was the optimum condition for drying of kaffir lime leaves. Moreover, effective moisture diffusivity coefficient was 1.4221x10-12 to 6.1840x10-12 m2/s. Effective moisture diffusivity coefficient was increased by decreasing of absolute pressure and increasing of drying temperature. Demir et al.’s empirical modelling was the best modelling for predicting of drying kinetic of kaffir lime leaves at decision coefficient was the highest at 0.99973, the lowest root mean square error was 0.00425 and the lowest chi-squared reduction was 0.03964x10-3.