Effect of ferulic acid covalent conjugation on the functional properties and antigenicity of ß-lactoglobulin.

ABSTRACT

Binding to phenolics can improve the functional properties of proteins. Changes in structure, functional properties, and antigenicity of ß-lactoglobulin (ß-LG) after covalent conjugation with ferulic acid (FA) at different mass ratios were reported here. The results of SDS-PAGE and gel exclusion chromatography confirmed that covalent complexes were formed. When the mass ratio of ß-LG and FA was 106, the binding content of FA was the highest. Fluorescence spectroscopy, UV-visible absorption spectrometry, and FTIR analysis showed that the structure of the complexes was more stretched compared to native ß-LG. The addition of FA significantly improved the emulsifying property of ß-LG. When the mass ratio was 106, the radical scavenging activities of DPPH and ABTS reached 65.06% and 88.22%, respectively, and the antigenicity of ß-LG reduced by about 35%. This study provides novel ß-LG-FA complexes in food systems to reduce the antigenicity of ß-LG and improve functional properties.