Additional Effect of Defatted Wheat Germ Protein Isolate on Nutritional Value and Functional Properties of Yogurts and Biscuits

Wheat germ is one of the potential sources of proteins at a relative low cost. This study aimed to investigate the effect of additional defatted wheat germ protein on nutritional value and quality of yogurts and biscuits. Defatted wheat germ proteins (DWGP) were extracted by one-step alkaline extraction using alkaline extraction at pH 9.5 and following isoelectric precipitation at pH 4.0. Yogurts were manufactured with 3, 6 and 9 g DWGP/100ml milk. Biscuits were prepared with 10, 20 and 30g DWGP/100g wheat flour (WF). Results found fortified yogurts had higher contents of protein, carbohydrate, and ash. Apparent viscosity and firmness, pH and total solids % values were higher. Prepared yogurts with 3and 6 g DWGP/100milk had significant higher scores of appearance and viscosity. Fortified biscuits had higher contents of protein and ash. Values of weight change %, thickness, volume, lightness, yellowness and saturation index were lower than that of the control. Biscuits with10 and 20g DWGP/100 g WF had higher color, firmness, and general acceptable scores than that of control. Conclusion: DWGP incorporation into milk yogurts and biscuit up to a level of 6g/100ml milk and 20g /100g WF, respectively had a higher acceptable for sensory and physical properties