DETERMINATION OF MOISTURE DIFFUSIVITY OF KOHILA DRYING IN A CONVECTION TRAY DRYER
G. K. Jayatunga1*, R. M. T. N. Rathnayake2 and N.K.T.A. Thilakarathne3
1,2,3Institute Technology University of Moratuwa, Homagama Sri Lanka
Session: Technical Session B
Abstract
Kohila (Lasia spinosa), a widely used ethnobotanical herb in Sri Lanka, is recognized for its therapeutic properties and potential in functional food development. This study investigates the drying kinetics of Kohila rhizome slices using a convection tray dryer at temperatures of 60°C, 65°C, and 68°C, with the aim of developing value-added, shelf-stable products. Sliced rhizomes (5 mm thick) were dried under controlled conditions, and moisture loss was recorded over time. Results indicate effective moisture diffusivity increasing with temperature. Estimated !eff values ranged from 2.83 × 10−7 to 7.50 × 10−6 m2/s. The activation energy for moisture diffusion was determined to be 8.52 kJ/mol, and the diffusivity coefficient was 6.75 × 10−9 m2/s. These findings provide essential insights for optimizing drying conditions and support the commercial utilization of Kohila rhizomes in dried or powdered form.
Keywords: drying kinetics, convection tray dryer, Kohila, diffusivity
DOI: 10.64752/PWYF8030