Ultrasonic regulation of β-lactoglobulin/puerarin complex: structural modification, digestive properties, and allergenicity suppression through controlled polyphenol interactions

This study explored the effects of ultrasound on β-lactoglobulin (β-LG)/puerarin (PUE) complexes, focusing on structural, digestive, and allergenic properties. Molecular simulations revealed hydrogen bonding as the primary interaction between PUE and β-LG. Ultrasound reduced β-LG crystallinity (via XRD), further enhanced by PUE encapsulation. Moderate ultrasound (300 W) increased thermal denaturation temperature by 8.2 °C (DSC) and enhanced digestibility to 78.3 ± 1.2 % (vs. 62.5 ± 2.1 % in untreated group), while excessive power (500 W) caused structural damage. Ultrasonic treatment increased the β-sheet content of β-LG, led to a reorganization of its tertiary structure. Allergenicity assays demonstrated significant reductions in IgE and IgG binding capacity for 300 W-treated complexes. These findings highlighted moderate ultrasound (300 W) as an effective strategy to modulate functionality and reduce allergenicity in protein-polyphenol colloids, offered insights for food science applications.