Comparison of quality characteristics between cooked rice and nurungji prepared by different rice cooker type

This study compared and analyzed the physicochemical and antioxidant characteristics between cooked rice and nurungji prepared by different rice cooker types, such as regular electric rice cooker EC, pressure electric rice cooker PC, siphon type rice cooker SC, and washdown type rice cooker WC. The moisture content of cooked rice and nurungji was significantly higher in WC4.1 and SC2.2, which had more water added, than those of control EC1.2 (p0.05). The pH of cooked rice ranged from 6.81 to 6.84, with no significant difference (p0.05). Both the total soluble solids content and reducing sugar content were significantly higher in nurungji compared to cooked rice. The total polyphenol and flavonoid contents were higher in nurungji than in cooked rice, and were significantly higher in PC1.2, while significantly lower in SC2.2 and WC4.1. Antioxidant activities, such as DPPH, ABTS, FRAP, and RP, showed a similar trend to those of antioxidant components. Conclusively, the use of a pressure electric rice cooker when making cooked rice and nurungji might be a positive aspect in terms of the antioxidant properties of the product.