Hygroscopic Behavior of Lyophilized Powder of Grugru Palm (Acrocomia aculeata)

The objective of this study was to determine adsorption isotherms and hygroscopic behavior of lyophilized powder from grugru palm. The powders of grugru palm were obtained by lyophilization process without maltodextrin (T1) and with 8% matodextrin (T2). The experimental data were obtained through the static gravimetric method at temperatures (25 ̊C, 30 ̊C, 35 ̊C and 40 ̊C), with different saturated solutions of salts. The models of GAB, BET, Henderson and Oswin were fitted to experimental data. The values obtained for hygroscopicity were 7.68% and 6.86% and the degrees of caking were 0.33% and 0.09% for T1 and T2, respectively. Mathematical models of adsorption isotherms for grugru palm powders can be classified as Type III. The GAB and Oswin models represented better the behavior of isotherms for T1 and T2. Grugru palm powder showed an increase in the humidity of the monolayer Xm along with increasing temperature. The grugru palm powder demonstrated to be a non-hygroscopic product, non-caking features.