Structural characteristics, functional properties and nutritional value of walnut protein by limited enzymatic hydrolysis

This study investigates the effects of limited enzymatic hydrolysis on the structural and functional characteristics, as well as nutritional value of walnut protein (WP). WP was hydrolyzed using papain to obtain varying degrees of hydrolysis (DHs) at 6, 8.33, 10 and 11.4%. The results indicate significant changes in the structural properties of WP due to papain hydrolysis. These changes primarily included a decrease in molecular weight, increased flexibility in secondary structure, reduced intrinsic fluorescence intensity, and a rise in H0 correlating with the DH increase. Accordingly, hydrolyzed WP displayed better functional properties and higher nutritional value. Notably, WP with a DH of 11.4% exhibited superior emulsification properties and the highest antioxidant abilities. In conclusion, the use of limited enzymatic hydrolysis with papain appears to be an effective approach for expanding the application of WP.