Osborne Fractionation and Functional Properties of Wheatbran Protein

Agricultural byproducts represent an underutilized source of nutrients with potential for human food applications. Upgrading feedstock into a food ingredient contributes to increasing the plant-based protein availability. Wheat bran, a major byproduct of wheat milling, accounts for 23–27% of total byproducts and contains 14–16% protein. This study investigates the functional and antioxidant properties of fractionated wheat bran proteins. The proteins were extracted and fractionated into albumin, globulin, and glutelin fractions using the Osborne method, yielding a total protein extraction yield of 58.8%. Amino acid composition indicated that albumin exhibited elevated levels of essential amino acids. Albumin and glutelin showed enhanced emulsifying and foaming properties under acidic and alkaline conditions, respectively. All three fractions exhibited excellent solubility profiles, with a sharp decrease in solubility around the isoelectric point. Albumin and globulin fractions exhibited enhanced water- and fat-holding capacities, respectively. Furthermore, albumin and glutelin exhibited excellent DPPH radical scavenging and ABTS inhibition activities. These findings demonstrate the potential application of wheat bran protein as a functional ingredient in food formulations.