The effects of β-lactoglobulin-puerarin interaction on the properties of protein hydrogels

This study investigated the impact of protein-polyphenol interactions on the properties of heat-set protein hydrogels. β-lactoglobulin (βLG) served as the model protein, while puerarin (PUE) was employed as the model polyphenol. Molecular docking simulations, combined with fluorescence spectroscopy, revealed that hydrophobic interactions dominated the interaction between PUE and βLG. Following PUE treatment, the particle size increased by 219 nm, and significant alterations were observed in the secondary structure. Scanning electron microscopy data illustrated notable surface modifications. The rheological properties of hydrogels can be modulated by varying polyphenol concentrations. Specifically, both the composite shear modulus and hardness of the hydrogels were enhanced with rising PUE concentrations. This study demonstrates that puerarin acts as a dual-functionality agent: a nutraceutical and a gelling enhancer. Its hydrophobic-driven complexation with βLG significantly increased particle size (by 131 %), storage modulus (by 220 %), and hardness (by 322 %).