Effects of freeze dryer temperature on drying kinetics of tofu

In the present investigation tofu was dried in freeze dryer at -40°C temperature. Drying characteristics of tofu viz. drying rates, moisture diffusivity were evaluated and the drying data of tofu was used to calculate the effective diffusion coefficients by the Fick's law equation of diffusion. The moisture diffusivity of tofu was found 2×10-8 m²/s. Also it was fitted to study the five models. Among the diffusion approach model was found most satisfactory to represent the thin-layer drying of tofu.