Grain characteristics, proximate composition, phytochemical capacity, and mineral content of selected aromatic and non-aromatic rice accessions commonly cultivated in the North-East Indian plain belt

Abstract

Rice is extensively used as a major food source, and thousands of rice accessions are sold throughout the world, which diverges significantly based on unique characters and nutrient and antioxidant profiles. This study evaluates six aromatic and four non-aromatic rice accessions from the Eastern Himalayan zone (North Eastern States of India) based on morphological and cooking quality, proximate compositions, different phytochemical capacity, and mineral contents. The result exhibited a significant difference in morphological traits among accessions. The proximate composition indicates that the highest moisture content was recorded in Gobindobhog (13%), protein and fiber in Jaya (9.93% and 0.74%), fat in Gopalbhog (0.99%), the ash content in Harinarayan (0.69%), carbohydrate in Setabhog (80.62%) and net food energy in Swarna (360 kcal/100 g). Phytochemical capacity was also significantly different among rice accessions; the highest total phenolic content (567.57 mg GAE/100), flavonoid content (218.24 mg QE/100 g), anthocyanin (35.90 mg cyanidin-3- glucoside Eq/100 g), and cysteine (8.41 µg/g fresh weight) was recorded with Manipuri Black Rice which is a pigmented rice variety. The mineral contents in rice accessions were also different; highest abundance of calcium was recorded in Gopalbhog (98.23 mg/kg), magnesium in Manipuri Black Rice (173.23 mg/kg), sodium in Setabhog (63.21 mg/kg), potassium in Setabhog (503.2 mg/kg), zinc in Manipuri Black Rice (17.98 mg/kg), copper in Remigeli (15.87 mg/kg) and iron in Manipuri Black Rice (37.6 mg/kg). The study concludes that the significant distinctiveness and difference in nutritional and phytochemical capacity will help make an outstanding market share for different rice accessions and help the farmer's decision-making.