Improving antioxidant activity of black bean protein by hydrolysis with protease combinations

Summary This study explored the use of a simplex centroid design to produce protein hydrolysates with antioxidant properties using Alcalase ® 2.4L, Flavourzyme ® 500L and Neutrase ® 0.8L. Proteases kinetic parameters and the ultrafiltration of protein hydrolysates were also investigated. The highest antioxidant activity, in the studied conditions, was reached when the mixture of Alcalase ® 2.4L and Flavourzyme ® 500L was used in the hydrolysates production. The antioxidant power of the black bean proteins, measured by the total antioxidant capacity and reducing power assay, increased after hydrolysis by 31% and 70%, respectively. The black bean proteins hydrolysates fractions (3–30 kDa) showed an antioxidant activity decrease along with a reduction in molecular weight, demonstrating that a set of varied molecular weight peptides was responsible for the antioxidant characteristics of black bean protein hydrolysates.