Quality Enhancement of Black Soybean [Glycine max (L.) Merrill] Flour using Germination Technique

Abstract

Background: Black soybean [Glycine max (L.) Merrill] is grown on 5734 hectare area of Kumaon and Garhwal region of Uttarakhand state of India but consumed on a very limited scale. The bioavailability of nutrients in soybean is limited due to presence of antinutritional factors such as trypsin inhibitors, oligosaccharides and tannins etc. Literature still lacks in data related to nutritional and health enhancing properties of black soybean, therefore, the present study was undertaken to enhance the nutritional quality of black soybean using germination technique. Methods: Two types of flour were developed from black soybean i.e. raw and 72-hours germinated flour which were analyzed for their proximate and mineral composition, antinutritional content, antioxidant activity, in-vitro protein digestibility, in-vitro iron bioavailability and dietary fibre content. Result: The findings revealed that germination led to significant (P<0.05) increases in crude protein, crude fibre, total ash, calcium, iron, magnesium, zinc, in-vitro protein digestibility and total dietary fibre content with significant (P<0.05) reductions in phytates, tannins, oxalates, trypsin inhibitor and oligosaccharide content of black soybean flour. The study concluded that germination significantly enhanced the nutritional properties of black soybean by increasing the density and bioavailability of nutrients and reducing the anti nutrients, thereby making it safer for human consumption.