Extent of decortication and quality of flour, couscous and porridge made from different sorghum cultivars

Abstract

Sorghum grain was decorticated to remove 10%, 20%, 30% and 40% of the kernel for the purpose of improving flour colour, couscous colour and yield, and porridge texture. Flour lightness increased while yellow colour decreased with increased extent of decortication. Processing of the flours into couscous caused a considerable drop in lightness and increased yellow colour in couscous at all levels of decortication. As decortication level increased, couscous colour became lighter. Yellow colour progressively increased up to 30% kernel removal and dropped at 40%. Couscous yield, as measured by the proportion of particles of 1-2 mm size, also increased up to 30% kernel removal. This improvement in yield was attributed to decreased proportion of bran as indicated by ash content. However, the yield dropped at 40% kernel removal due to formation of large chunks of agglomerated flour particles. Thick porridge became harder as decortication level increased and this was strongly associated with the concomitant increase in starch concentration. Overall, this study defined the decortication levels necessary to improve the couscous colour and yield, and texture of porridge made from different sorghum cultivars.

Sorghum flour fractions: Correlations among polysaccharides, phenolic compounds, antioxidant activity and glycemic index

“…The highest was found in DSF (p < 0.05) ( Table 2). These results are in agreement with literature, which describes sorghum bran as rich in lipids, minerals and dietary fiber, while decorticated sorghum flour concentrated the highest content of carbohydrates (Aboubacar et al, 2006). Overall, grains are not a good source of soluble fiber (Kumar, Sinha, Makkar, de Boeck, & Becker, 2012); which are shown by the same soluble fiber content between SB and WSF; and between WSF and DSF.…”

“…On the other hand, while decortication decreases phenolics and antioxidant activity in sorghum, the remaining decorticated grains may improve color, reduce astringency and improve digestibility of sorghum products (Aboubacar et al, 2006). It should be highlighted that sorghum decortication provides distinct products which may be applied in different food industry fields according to target consumers.…”

“…Phenolics compounds and dietary fiber are concentrated in the bran, whereas starch is the main component in grits (endosperm). The distinct composition between both products guides sorghum bran to be used as a functional ingredient to enhance the consumption of healthy food, while decorticated grains produce lighter products to attend other food industry fields (Aboubacar, Yazici, & Hamaker, 2006;Awika, McDonough, & Rooney, 2005;BuitimeaCantúa et al, 2013;Dlamini, Taylor, & Rooney, 2007).…”

Effect of decortication and protease treatment on physicochemical and functional characteristics of red sorghum (Sorghum bicolor) and yellow maize (Zea maiz) starches

“…The mechanical removal of the sorghum outer layers will yield a shelf stable sorghum bran rich in dietary fiber and nutraceuticals that do not require drying, and the resulting pearled kernels a better raw material due to their higher starch content. On the other hand, the diffusion of the sulfur dioxide into decorticated kernels will be enhanced and the endosperm protein structures readily digested with proteases . These enzymes do not have residual amylolytic activity and can effectively hydrolyze endosperm proteins (protein bodies and matrix), and can aid to synergistically enhance (in combination with wet milling) both starch yield and purity without significantly affecting the starch physicochemical and functional characteristics .…”

“…On the other hand, the diffusion of the sulfur dioxide into decorticated kernels will be enhanced and the endosperm protein structures readily digested with proteases . These enzymes do not have residual amylolytic activity and can effectively hydrolyze endosperm proteins (protein bodies and matrix), and can aid to synergistically enhance (in combination with wet milling) both starch yield and purity without significantly affecting the starch physicochemical and functional characteristics . The aim of this research is to increase starch yield and recovery performance from red sorghum kernels subjected to mechanical decortication and with the use of a protease (NEUTRASE®) during the sulfur dioxide wet‐milling process and compare its starches physicochemical and functional characteristics.…”