Characteristics of IgE/IgG affinity and glycosylation sites in β-lactoglobulin subjected to synergistic HHP and galactose oligogalactose treatment

Abstract

This study investigates the efficacy of High Hydrostatic Pressure (HHP) coupled with glycosylation as a novel approach to modulate β-lactoglobulin, a predominant allergenic protein in milk. The objective is to attenuate its allergenic potential while preserving its physicochemical attributes. A comprehensive array of analytical methods, including spectroscopy, chromatography, mass spectrometry, and ELISA, were deployed to elucidate the mechanisms underlying the observed alterations in allergenicity. Our findings reveal that HHP-assisted glycosylation induces structural modifications in the protein, facilitating the covalent linkage of oligogalactose moieties to β-lactoglobulin. This structural alteration culminates in a marked reduction in the immunogenicity of β-lactoglobulin. The decrease is primarily attributed to modifications in specific amino acid residues—namely, Lys14, Lys101, Lys124, and Arg148—and the introduction of glycosylation at the Arg40 site. The synergistic effect of HHP and glycosylation not only mitigates the allergenicity of β-lactoglobulin by obscuring linear epitopes and altering its conformation but also enhances its physicochemical functionalities, including emulsifying properties, solubility, and antioxidant activity. These insights offer a robust theoretical foundation for the formulation of hypoallergenic whey protein products.