The Impact of Stabilization on Functional, Molecular and Thermal Properties of Rice Bran

Abstract

The objective of this study was to determine the effects of different stabilization treatments on the functional properties of rice bran (RB). This work also determined the molecular and thermal properties of stabilized RB. RB was stabilized by conventional oven and microwave (MW) oven. Three different oven temperature (120, 140 and 160 degrees C) and three different MW power (600, 700 and 800 W) were used for stabilization. Stabilization procedures significantly affected the antioxidant activity, phenolic profile and protein fractions of RB. The antioxidant activities of the RB increased significantly with the stabilization. Microwave-based (MW) stabilization decreased the amount of albumin-globulins and prolamins (p < 0.05) and it did not change the amount of glutelins (p > 0.05). Conversely, the stabilization with conventional oven significantly increased the amount of albumin-globulins and prolamins and it significantly decreased the amount of glutelins. The results obtained from Fourier-transform infrared spectroscopy (FTIR) spectra, showed that stabilization changed the intensity and location of some bands. The best method to reduce the lipase activity and to improve the functional properties of RB was MW based treatment. Also, thermal decomposition was delayed by MW based stabilization. Consequently, it was revealed that MW based treatment was short-term and effective method to stabilize of RB.