Moisture Sorption Characteristics of Blanched and Osmotically Treated Apples and Papayas

ABSTRACT The moisture adsorption and desorpcion characteristics of blanched and osmotically treated apples and papayas and the color of the equilibraced samples were evaluated at 25-C. The sorption isotherms were in agreement with the reported shape for high sugar foodstuffs. A two-way analysis of variance showed that there was not hysteresis for the blanched fruits; however, this phenomenon was present in the osmotically treated samples. Different equations proposed in the literature were used to fit sorption data. The best fit was obtained with GAB model (average mean relative deviation of 9.8%). The apples' white and the papayas' yellow indexes of the equilibrated fruits decreased as a, increased. Browning of the apples varied with the type of isotherm (adsorption or desorption) and with the initial sugar content.