Hygroscopic behavior and degree of caking of grugru palm (Acrocomia aculeata) powder.

This work aims to investigate the hygroscopic behavior of grugru palm powder through adsorption isotherms and its degree of caking. The powders of grugru palm (T1 - without maltodextrin, T2 - with 8 % of maltodextrin) were obtained by oven drying at 65 °C for 25 h. The experimental data was obtained through static gravimetric method at temperatures of 25, 30, 35 and 40 °C with different saturated salt solutions. The models of GAB, BET, Henderson, and Oswin were fitted to experimental data. The values of hygroscopicity were 6.39 and 5.17 % and degrees of caking were 3.11 and 0.03 % for T1 and T2, respectively. The adsorption isotherms from mathematical models can be classified as Type III. The GAB and Oswin models were the best representing the behavior of the powder isotherms, T1 and T2, respectively. The grugru palm powder proved to be non-hygroscopic and non-agglomerating. The T2 with 8 % of maltodextrin presented the lowest hygroscopicity.