Effect of gamma irradiation on physicochemical, functional and pasting properties of some locally-produced rice (Oryza spp) cultivars in Ghana

Rice (Oryza sativa L.) is a staple crop in Ghana and much of West Africa, where it serves as an important convenience food for urban consumers. The objective of this study was to determine the effect of gamma irradiation as insect disinfestation technique on some physicochemical, functional and pasting properties of selected locally-produced rice cultivars in Ghana. Four local rice cultivars and an imported (commercial) type were purchased, cleaned and irradiated at doses of 0.0, 0.25, 0.50, 0.75,1.0 and 1.5 kGy. The irradiated rice cultivars were milled and their physicochemical, functional and pasting properties determined. There were reductions in pH and swelling power, as well as increase in solubility of rice cultivars after gamma irradiation. Gamma irradiation did not change the XRD pattern of the rice cultivars. Gamma irradiation significantly (P < 0.05) decreased peak time for BAL and VNT rice cultivars. Gamma irradiation significantly (P <0.05) decreased PV, HPV, BDV, FV and SBV for all the rice cultivars. This study shows that flours from gamma irradiated rice cultivars have potential in food formulations that require low viscosity. (C) 2016 Elsevier Ltd. All rights reserved.