Physicochemical and functional properties of heat-moisture treated rice starches with different organic and additions

Abstract

Effect of organic acid additions and heat-moisture treatment (HMT) on physicochemical and functional properties of rice starches was studied. Isolated rice starches was subjected to HMT with adding different organic acid solutions (0.2M acetic acid, 0.2M citric acid and 0.2M lactic acid) to 30% moisture levels and heated at 11 0°C for 8 hours. The impact on the yields of resistant starch (RS) content, physicochemical and functional properties was investigated. Compared to native starch, the RS content of acid and heat-moisture treated (A-HMT) starches significantly increased. In addition, results reveal that swelling power of treated starches decreased while solubility greatly increased. The reduction of viscosity and paste clarity of A-HMT starches were obtained. The X-ray patterns of A-HMT starches practically unchanged as compared to that of native starches. As a result, acid and heat-moisture treatment (A-HMT) improved the functional properties of rice starches. Keywords: heat-moisture treatment, rice starch, resistant starch, acid hydrolysis