Osmotic drying kinetics of pineapple and papaya

Abstract

Two osmotic dehydration processes were studied for pineapple and papaya: immersion in sucrose 70° Brix syrup; and in sucrose 70° Brix with 1000 p/m potassium sorbate ana 150 p/m sodium metabisulfite syrup. The additives acted not only as preservatives but also in some way helped increase the driving force of the osmotic solutions, lowered the water activity of the final fruit products, and raised the final pH of the solutions, but did not affect that of the fruits. Pineapple had a greater tendency for absorbing sugar than papaya, and papaya induced fewer chemical changes in the osmotic solution than pineapple. Therefore, the immersing solutions can be recycled more times with papaya than with pineapple.