Prediction of Pineapple Sorption Isotherms Using the Ross Equation

A mathematical prediction of pineapple sorption isotherms was developed using Ross, Norrish and Henderson equations. The prediction considered to have the pineapple average composition oflhe main solutes: sucrose, glucose, fructose, citric acid, malic acid, NaCI, KC1 and cellulose as non-solute. Water activity of individual sugars and organic acids was obtained by Norrish's equation and for the two salts by Raoult's Law. Solute solubility at different temperatures was taken into account. Predicted isotherms were compared with the experimental isotherms obtained in laboratory at 30, 35, 40 and 45° C and with the isotherms reported in literature at 30 and 45° C. The generalized correlation coefficients ( r2 ) between predicted and experimental isotherms were in the range of 0.8 - 0.98.