Effect of growing environments on the minerals and proximate composition of urdbeans (Vigna mungo L. Hepper)

Urdbean (Vigna mungo L. Hepper) is an abundantly grown and profusely consumed south-Asian pulse crop. It has enormous scope in the international food industry, being a high-value and low-carbon footprint source of several nutrients and micronutrients. The present study was conducted in a set of urdbean genotypes of diverse origins - to validate high sources for iron and zinc concentrations in urdbean based on replicated field trials, to determine the effect of growing environment on these traits, to quantify phytic acid concentration, to quantify fats, carbohydrate, dietary fiber, protein content and to generate Fourier Transformed Infrared Spectroscopy profile of these urdbean genotypes. Analysis of variance showed that genotypic effects were significant (p < 0.05) at all locations for iron and zinc concentrations. The mean value of Fe and Zn concentrations were 97.1 mg/kg and 14 mg/kg, respectively, over the locations. Fe and Zn concentration ranged between 86.7 (LBG-787) to 116 (WBU-108) mg/kg and 11.2 (VBN-7) to 18.2 (IPU99–79) mg/kg, respectively. Moisture, protein, fat, ash, total fiber, and total carbohydrate contents were 11.5, 25.3, 1.1, 2.95, 13.9, 57.5%, respectively. The phytic acid content was stable over the locations, ranging from 13.7 mg/g to 14 mg/g for the 20 tested urdbean genotypes. In this study, genotype, PLU 429, which had Fe concentration ranging between 81.6 and 93.5 mg/kg, is a superior genotype with the lowest PA content (10 mg/g) over the three test locations. Fourier Transformed Infrared Spectroscopy profiling detected three urdbean- specific sharp peaks between 4000 and 3500 wave numbers. Among these, two peaks (3724, 3625 wave numbers) were due to free O-H stretching of alcohols. In GGEBiplot analysis, the most stable urdbean genotypes with high Fe concentration were PU-30 (102 mg/kg) and Shekhar 2 (105 mg/kg), and for Zinc concentration, WBU137–2 (15.2 mg/kg) and UH85–5 (15.4 mg/kg) were having high concentration as well as comparatively higher stability. In conclusion, urdbeans were identified as stable sources of high iron and zinc concentrations, and a lower anti-nutrient concentration may help breed for nutrient-dense urdbean cultivar.