Moisture adsorption characteristics and storage stability of rice bran protein concentrate.

Abstract: Water activity and equilibrium moisture data of full-fat and defatted rice bran protein concentrate powder at a fixed temperature of 27°C were obtained from apparatus designed for the purpose. The data were analysed for the determination of values of bound water, water activity for the maximum stability, moisture content at the change over points in the nature of moisture binding and energy required for the removal of bound water in these materials. BET, Caurie, Stability, «Local», and «GAB» isotherm models were used for analysing the data. Rice bran protein concentrates were found to be stable for storage in the water activity ranges of 0.2 to 0.4 and 0.35 to 0.36, which correspond to the equilibrium moisture contents of 2.8 to 3.8 and 3.2 to 3.7% respectively, for full-fat and defatted samples