The Effect of Fermentation, Malting, and Cooking on Protein Content and Fractions of Sorghum Cultivars

This study examined the effects of fermentation, malt addition, and cooking on the protein content and protein fractions of low- (Mugud) and high-tannin (Karamaka) sorghum cultivars. The flour of the seeds of both cultivars was mixed with 5% malt. Then, the flour, with or without malt, was fermented for 16 h. Samples were taken every 4 h during fermentation to monitor changes in pH, titratable acidity, protein content, and protein fractions. Additionally, the fermented flour, with or without malt, was cooked to analyze changes in the protein fractions of the cultivars. The fermentation of flour, regardless of malt addition, elevated crude protein content and titratable acidity while reducing pH in both cultivars. A significant (p < 0.05) increase in the (globulin + albumin) percentage was noted during the fermentation of both cultivars’ flour, while other fractions exhibited variability. Cooking the fermented dough significantly (p < 0.05) reduced the fractions of both cultivars, except for G3-glutelin and insoluble proteins, which were increased significantly (p < 0.05). Malting followed by fermentation had a slight effect on the fractions, except for G3-glutelin and insoluble proteins, which were significantly (p < 0.05) reduced for both cultivars. The results revealed that adding malt to sorghum flour and fermenting it is a valuable method for improving the nutritional quality even after cooking.