Effect of heat moisture treatment on the physicochemical, functional, and antioxidant characteristics of white sorghum ( Sorghum bicolor (L.) grains and flour

Abstract

This study aims to study the effect of Heat Moisture-Treatment (HMT) on the physicochemical, functional, crystallinity, and antioxidant properties of five white sorghum varieties, namely CO30, K12, Parbhani Moti (PM), Parbhani Shakti (PS), and ICSV15021. The sample grain's moisture content was adjusted to 17% and subjected to HMT (100°C) for 4 hr. The HM-treated samples showed higher carbohydrate [71.82 g/100 g(PS)–76.25 g/100 g (PM)] and crude fat content [2.12 g/100 g (ICSV15021)–5.52 g/100 g (K12)] than the control. In contrast, the crude protein [7.22 g/100 g (PM)–9.77 g/100 g (CO30)] and ash content [1.85 g/100 g (CO30)–2.57 g/100 g (PM)] got decreased in HM-treated samples comparing control. Significantly higher DPPH-antioxidant activity was recorded in HM-treated samples [31.72% (ICSV15021)–51.07% (K12)] than control. Similarly, the water and oil absorption capacity was found to be higher in HM-treated samples [2.80 g/g (PM)–3.28 g/g (ICSV15021) and 2.45 g/g (PM)–2.8 g/g (CO30)] than control. The crystallinity got reduced after HMT [11.73% (CO30)–15.17%(PM)], and both control and HM-treated sorghum flours exhibited an A-type diffraction pattern. Practical applications As whole sorghum flour has limited usage in the food processing industry, the modifications using heat treatment could increase sorghum utilization in developing novel biofortified and gluten-free food products. HMT positively influences the physicochemical, functional characteristics with the increased antioxidant activity of five varieties of white sorghum grains. Hence, HMT physical modification of sorghum grain makes it suitable in both the novel food system for developing unique gluten-free, biofortified products and other nonfood applications.