Abstract:The soybean protein extracted from low-temperature defatted soybean meal was hydrolyzed with alkaline protease，papain，or a combined method with both enzymes.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE）and competitive enzyme-linked immunosorbent assay（ELISA）were used to determine the changes in components and antigenicity of the hydrolyzed proteins.The results showed that the αsubmit and α'-submit of 7S components of soybean protein almost disappeared after a 30-min hydrolysis with alkaline protease，and all the submits were hydrolyzed with papain for 10 min；however，many new bands with a molecular weight of less than 30 kDa were produced and showed strong resistance to enzymatic hydrolysis.The hydrolysis with the combination of enzymes eliminated peptides that were not hydrolyzed with alkaline protease，and it did not generate new peptides to be hydrolyzed with papain.After a 120 min hydrolysis with alkaline protease，papain，and the two combined enzymes，the antigenicity of 7S components of soybean protein decreased to 64.25%，48.79%，and 28.57% of the original protein，and the antigenicity of 11S components decreased to 78.43%，62.35%，and 33.93% of the original protein，respectively.The results showed that the hydrolysis with the two enzymes combined was more effective than that of the single enzyme.