Physicochemical, Functional and Antioxidant Properties of Pigmented Rice

Pigmented rice has hight antioxidant nature, and its properties contribute to the successful formulation of nutraceutical food products. Based on this background, this research was aimed at determining the physicochemical, functional and antioxidant properties of ten pigmented Indonesian rice varietiels - Merah Saleman, Mota, Beureum Taleus, Anak Doro M, Cempo Salamet, Ketan Putri, Ketan Hitam I, Ketan Hitam II, Gogo Niti II, and Care Hitam. The physic properties and proximate analysis of pigmented rice were showed a significant difference at p<0.05, except for crude fiber. The sample with the lowest amylose showed the highest peak, trough, and final viscosities, but with low pasting temperature. The gelatinization enthalpy ranged from 0.82 - 1.33 J/g, and the sample with the highest amylose had the lowest gelatinization peak. The functional properties of the water absorption index ranged from 4.22 - 7.63 g/g, the water solubility index was between 3.62 - 7.40%, the oil absorption index varied from 0.88 - 1.36 g/g, while the swelling power was between 5.31 - 8.42 g/g. Furthermore, the antioxidant properties of the samples measured in terms of the phenolic content ranged from 2.17 - 10.60 mg GAE/g, the flavonoids varied from 0.43 - 2.31 mg QE/g and their activity used the stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. The total flavonoid in the phenolic component was positively correlated with the antioxidant activity. In conclusion, the ten pigmented rice showed a wide range of physicochemical, functional, and antioxidant properties, making the samples useful for the formulations of various products with health benefits.