LAUSR

Sorghum (Sorghum bicolour (L.) Moench) is an important basic food eaten in warm and semi-arid regions of the world. It is rich in carbohydrates, fibre, vitamins, minerals and phytochemicals, including tannin, phenolic acids, anthocyanin and phytosterol (Girard & Awika, 2018). These nutrients play an important role in the health and nutrition of human beings, especially in the case of persons who suffer from lifestyle disorders like celiac disease, diabetes and obesity (Pontieri et al., 2013). However, it is well known that tannins can reduce starch digestibility, which is why, different methodologies to reduce its concentration have been suggested. One of these methodologies is based on a hydrothermal treatment (Acquisgrana et al., 2016, 2019, 2020), which is the one that is going to be used in this work. Particle size reduction takes place as a preliminary step before the product development process (Duodu et al., 2002) which results in the rupture of the outer layer of the seed coat to expose the endosperm and its resulting fracture. Conventional size reduction machines for grain preparation in food processing include hammer mills, roll mills and friction mills (Mahasukhonthachat et al., 2010). They vary in the effective operation force and the amount of heat generation through friction during milling. These friction heat and mechanical energy could affect the molecular and structural properties of starch (damaged starch) and other components, which affects its functionality (Liu et al., 2014). The damage of starch granules caused by milling increases the water retention capacity of flours (Acquisgrana et al., 2020) due to the increase of the levels of starch exposed to hydration and to enzymatic action.