Proximate composition and mineral content of underutilized legumes from semi-arid regions

Abstract:

Horse gram, moth bean, and rice bean three legumes widely grown by subsistence farmers in semi-arid zones are seldom found in modern food composition databases despite their apparent nutritional promise. This research determined the proximate composition and mineral content of these three underutilised legumes collected from semi-arid growing regions of India and compared them to cowpea and chickpea as reference species. Analyses followed standard AOAC methods at the Department of Food Chemistry, Delta Valley University of Agriculture, Memphis, Tennessee, between January and August 2022. Protein content ranged from 20.1% (rice bean) to 23.6% (moth bean), comparable to cowpea (24.1%) and exceeding chickpea (19.3%). Iron was highest in horse gram (6.7 mg/100 g), nearly double that of chickpea (3.6 mg/100 g). Calcium ranged from 156 mg/100 g in rice bean to 287 mg/100 g in horse gram. All three underutilised species had low fat content (<2%), making them suitable for low-fat food formulations. Anti-nutritional factors (phytic acid, tannins) were present but within ranges reported for other edible legumes. Results indicate that horse gram, moth bean, and rice bean deserve greater attention from food scientists and policy-makers seeking affordable plant-protein sources for food-insecure populations.