Effects of γ-irradiation on phenolics content, antioxidant activity and physicochemical properties of whole grainrice

Three rice genotypes with different color were gamma irradiated at a dose of 2, 4, 6, 8and 10 kGy. The aim of this study was to investigate the effect of gamma irradiation on the phenolics content and the antioxidant activity, as well as physicochemical properties of whole grain rice. The bound phenolics content in all the genotypes were significantly increased with the increase of dose of irradiation. Gamma irradiation at high dose significantly increased the free, bound and total antioxidant activities of three rice genotypes except for the free antioxidant activities of red rice. Though the color parameters were slightly changed, these changes could not be visibly identified. Rapid visco-analyzer (RVA) viscosities and gel hardness decreased continuously with the increase of the irradiation doses. It is suggested that gamma irradiation enhanced the antioxidant potential and eating quality of whole grainrice.

► Effects of irradiation on physicochemical properties of three rice were investigated.
► The bound phenolics and its antioxidant capacity were increased with the dosage increase.
► The color parameters of flour were slightly affected by irradiation.
► The viscosity and gel hardness were decreased continuously with the dosage increase.