Sorghum–mung bean combination snacks: Effect of extrusion temperature and moisture on chemical, functional, and nutritional characteristics

Abstract

Nine samples were formulated using whole sorghum–mung bean (70:30) at variable extrusion conditions: barrel temperature (130–170°C) and feed moisture (14–18%), and their effect on properties of snacks was examined. The results revealed that the elevation in temperature and moisture increased the antioxidant activity (ferric-reducing antioxidant power and 2,2-DiPhenyl-2-Picryl hydrazyl hydrate) and total phenolic content. This could be attributed to that the release of bound phenolics is accelerated by the extrusion treatment. However, higher temperature and lower moisture improved the functional properties such as expansion ratio, in vitro protein digestibility, overall acceptability, and expected glycemic index (50–51) of the snacks. A positive correlation was seen among slowly digestible starch and expected glycemic index of the snacks, water solubility index, and expansion ratio. A strong positive correlation was observed among total phenolic content and antioxidant activity. Higher barrel temperature (170°C) and a lower feed moisture (14%) were found to be the best combination to produce nutritious sorghum–mung bean-based snacks. Moreover, the snacks were found to be highly likeable among the sensory panel, which proves its commercialization properties.