Stability-Indicating Stabilization of Rice Bran Food Value by Heat Treatment

Abstract

Rice bran (RB) is a natural source of nutrients that help to reduce oxidative-stress related diseases. But stability-indicating stabilization of RBfood values are still challenging due to degradation of excessive lipid contents eventually produces off-flavors and odors. This study aims stability-indicating stabilization of RB food value by heating such as autoclave (1200C, 180min by HICLAVETM,HVE-50instrument), roasting (1500C, 10min by Heating oven), steaming (1200C, 120min by Domestic cooking steamer) and microwave (1500C, 3min by Domestic microwave oven, WALTON, Bangladesh)followed by stability testing at -200C and 40C for 16 weeks. We measured the proximate composition, phenolic content, tannic acid, flavonoid, antioxidant activity, IC50 value, oxidative stability, peroxide and acid value, oil extraction before and after aforementioned treatment of RB. It was found that roasting and microwave treatment significantly (P < 0.05) increased the stability of macronutrients as well as corresponding oil extraction yield. Moreover, roasting and microwave treatment significantly (P < 0.05) increased the stability of total tannin, flavonoid and antioxidant activity. Though roasting technique decreased the stability of monounsaturated fatty acid but increased gamma-oryzanol content and poly unsaturated fatty acid. In conclusion, the technique of roasting and microwave heating are more efficient for stability-indicating stabilization of RB food value.