Gluten-free foods continue to be a hot topic and trend in the food market because more people are being diagnosed with gluten intolerance. Whey is a by- or co-product of the dairy industry and is considered a waste stream. In this study, whey protein concentrate (WPC), one of the whey products, was added at 8, 9, 10, 11 and 12% levels to sorghum and corn flours to make gluten-free products in the form of cookies. Mixograph and subjective evaluation showed that optimal water absorption (corn: 50–55%; sorghum: 55–60%) increased with increasing WPC level in both sorghum and corn flour dough systems. Increasing WPC from 8 to 12% resulted in a decrease in storage modulus (G’) and loss modulus (G’’) for both sorghum and corn doughs. Corn dough rheological properties were less affected by WPC addition as compared to sorghum. The diameter of gluten-free sorghum and corn cookies significantly increased with the fortification of WPC. The color of sorghum and corn cookies became darker as the WPC level increased. Cookies prepared with 10% WPC addition showed the most hardness and brittleness, probably due to the gelling property of WPC. This study contributes to the sustainable utilization of whey product and helps understand the performance of WPC during the processing of gluten-free products and its potential for making food snacks such as cookies in food manufacturing.

This study evaluated the refinement of sorghum, corn, and cowpea grains using the processing steps and equipment originally designed for wheat milling that consists of a conventional gradual reduction system. The need to mill these grains resulted from a desire to produce alternative ingredients for developing new fortified blended extruded foods used for food aid programming. Milling of white sorghum grain resulted in a crude protein content of 7.4% (wb) for both whole and coarse-milled flour. The crude protein content in whole fine-milled sorghum was 6.8% (wb), which was significantly lower than that of whole coarse flour at 9.3% (wb). A decrease in the ash content of sorghum flour correlates with the decortication process. However, degermed corn, fine and coarse, had significantly different crude protein content of 6.0 ± 0.2% (wb) and 7.7 ± 0.06% (wb), respectively. Degerming of corn improved the quality of corn flour (fine and coarse) by reducing the crude fat content from 3.3 ± 0.18% (wb) to 1.2 ± 0.02% (wb) and 0.6 ± 0.13% (wb), respectively. This helped increase the starch content from 60.1 ± 0.28% (wb) in raw corn to 74.7 ± 0.93% (wb) and 71.8 ± 0.00% (wb) in degermed fine and coarse corn flour, respectively. Cowpea milling did not produce differences in the milling stream outputs when the crude fat and crude protein were compared. Whole flour from the grains had higher milling yields than decorticated flour. This study demonstrated that a mill dedicated to wheat size reduction can be adapted to refine other grains to high quality.

This review examines sorghum digestibility from molecular structure to clinical implications, focusing on compositional factors, processing methods, and health outcomes. We evaluate how sorghum’s unique protein–starch interactions influence digestibility and explore emerging technologies that can modulate these properties for targeted nutritional benefits. Cooked sorghum generally has lower digestibility than raw sorghum and other cereals due to heat-induced protein–starch cross-linking and the formation of disulfide bonds by sorghum proteins (kafirins), which restrict enzymatic access. Enzyme inhibitors in sorghum further reduce starch hydrolysis. This reduced digestibility may negatively impact malnourished individuals and those relying on sorghum as a dietary staple. However, it can be advantageous to individuals with diabetes by lowering postprandial blood glucose levels. Sorghum consumption may also beneficially influence the gut microbiome. Certain processing methods have been shown to significantly enhance digestibility while preserving beneficial bioactive compounds. Improving digestibility through these strategies may enhance sorghum’s value for vulnerable populations while maintaining its metabolic advantages. Balancing increased nutrient bioavailability with preservation of beneficial functional properties is critical for optimizing sorghum as a health-promoting grain across diverse populations.