Physico-chemical and antinutritional attributes of gamma irradiated Vigna unguiculata (L.) Walp. subsp. unguiculata seeds

Effect of gamma irradiation on Vigna unguiculata subsp. unguiculata seeds (black coloured seed coat) at various doses (2, 5, 10, 15 and 25 kGy) on the physico-chemical characteristics, proximate composition, vitamins (niacin and ascorbic acid) and antinutritional factors were investigated. No significant changes were observed in the physico-chemical characteristics of irradiated seeds. Gamma irradiation resulted in a significant increase of crude protein at all doses, while the crude lipid, crude fibre and ash content showed a dose dependent decrease. Raw seeds were rich in vitamins (niacin and ascorbic acid); when the seeds were irradiated, significant decreases were reported. Irradiation processing significantly reduces the levels of L-DOPA, phytic acid, hydrogen cyanide, trypsin inhibitor activity, oligosaccharides and phytohaemagglutinating activity. Total free phenolics, tannins and in vitro protein digestibility showed significant dose dependent increase. As irradiation is a physical and cold process, it may be ideal and emerge as an important technique to improve the nutritional quality of legume seeds and its products.