MODELING OF MASS TRANSFER KINETICS OF PEAR (PYRUS COMMUNIS L.) IN TERNARY SOLUTIONS OF SUGAR AND CALCIUM SALT DURING OSMOTIC DEHYDRATION

摘要

The mass transfer kinetics of pear in ternary solution was studied at an optimized condition derived using the Box Behnken Design of Response Surface Methodology (R.S.M.). The optimized conditions were found for minimizing solid gain and water activity and maximizing water loss, weight reduction and overall acceptability. The osmotic dehydration kinetics data were fitted in viz the Magee model, Page's model and Azuara model. In a comparative study of mass transfer kinetics of Pear between three models viz the Magee model, Page's model and Azuara model; Page's model was found to fit more effectively to Pear, for the prediction of water loss and solid gain kinetics during the osmotic dehydration. The simplified solution of Fick's second law of diffusion for a slab geometry was used to calculate the average values of apparent diffusion coefficient (De(f), namely 4.24x 10'08 m2/s for WL and 4.13x 10"08 m2/s for SG.