Behavior of adsorption isotherms of freeze-dried mango pulp powder/Comportamento das isotermas de adsorcao do po da polpa de manga liofilizada

The content of water and how it binds to food influence the quality and shelf life of fruit powder. The hygroscopic behavior of powder food can be evaluated by the study of moisture sorption isotherms. This study aimed to evaluate some mathematical models to represent the sorption isotherm of freeze-dried mango pulp powder and to evaluate physicochemically mango pulp and mango pulp powder. The analyses were moisture, pH, total soluble solids, total titratable acidity, ascorbic acid and color. The models adjusted to data were BET, GAB, Henderson and Oswin models at 25, 30 and 35 [degrees]C. The GAB model showed the best fit. The GAB model showed mean errors of 4.092 to 5.175% and [R.sup.2] values from 0.9986 to 0.9993 for the all temperatures. The isotherms of freeze-dried mango pulp showed characteristic shape of type III.