Effect of germination on techno-functional and nutraceutical properties of cowpea (Vigna unguiculata) flour

Abstract

Germination is an economic and feasible process that have demonstrated changes in nutritional, biochemical and sensorial properties on cereals and legumes. The present work presents the impact of germination, at two different times (24 and 48 h) and temperatures (18 and 35 °C) on techno-functional, nutraceuticals and nutritional properties of Vigna unguiculata (cowpea) flours. Germinated V. unguiculata (cowpea) flours showed a higher protein content (22.19%–23.30%) than ungerminated flour (20.72%), as well as an increase in ash and total dietary fibre content. In contrast, lipid content was reduced by half when germinated at 48 h and 35 °C. The values for phenolic compounds in germinated flours ranged from 10.22 to 21.94 mg GAE/g. The flavonoid content decreased between 10% and 31.5%. Antioxidant capacity increased after germination. Regarding techno-functional properties, darker colour was obtained for germinated flours and more yellowness. For water absorption capacity, a range of 1.7–2.9 g/g were obtained, and an increase in oil absorption capacity was observed. Germination for 48 h and 35 °C resulted in a significant improvement of nutrient content and bioactive properties and showed good techno-functional properties.