Agricultural Research Journal

Drying kinetics of bittergourd (Momordica charantia) was studied using multilayer drying method. The drying was carried out at 5 levels each of loading densities (31–60 kg/m²) and air velocities (2.60 –5.41 m/s). The drying kinetics parameters studied were moisture content, drying rate, temperature of outgoing air, temperature of product and heat utilization factor. The time elapsed to attain constant weight was observed to be 210 – 480 min in selected drying conditions. Increase in air velocity resulted in increase in temperature of outgoing air and product. However heat utilization factor showed opposite trend. The maximum moisture diffusivity was found 7.22 × 10⁻⁷ m/s at 31 kg/m² & 5.41 m/s. The air velocity had a pronounced influence on the drying rate and thus markedly affected the diffusion coefficient. The Page model best described the drying behaviour of multilayer dried bittergourd slices with high goodness of fit (R²>0.99).