Nutritional Composition, Mineral Content and Antioxidant Properties of Unpolished Red Rice Cultivars of Assam, India

Abstract

Background: Assam is a rich source of different types of colored rice cultivars. Very few colored rice cultivars are studied regarding nutritional and phytochemical properties. The objective of present study was to assess the nutritional composition and antioxidant properties of traditional red rice cultivars of Assam. Methods: Ten different red rice cultivars were collected for the study. The unpolished rice grains were analysed for proximate composition, mineral content, total phenolic, flavonoid content and DPPH free radical scavenging activity. Result: Amylose content was found to be low in the red rice cultivars. The carbohydrate and crude protein content varied significantly among the red rice cultivars. The studied cultivars were found to be good source of Fe, Mn and Zn. Highest total phenolic (1357.22 mg /100 g) and flavonoid content (896.37 mg/100 g) were found in the Hal aus, whereas the lowest value for total phenolic (336.49 mg/100 g) and flavonoid content (127.51 mg/100 g) were observed in Basanta bahar. Antioxidant capacity of colored rice varieties ranged from 33.33 to 84.24% for DPPH radical scavenging activity. The red rice cultivars contain a significant amount of nutrients and antioxidants including phenolic and flavonoids.