Cold plasma-induced amyloid fibrils of β-Lactoglobulin: Structural modulation, antigenicity reduction, and emulsification enhancement

The effects of cold plasma (CP) treatment on the formation of β-lactoglobulin (β-LG) amyloid fibrils (AFs) and its impact on the antigenicity and emulsifying properties of β-LG, were investigated. Results indicated that moderate CP treatment significantly accelerated AFs formation, and remodeled the fibril structure of β-LG, as evidenced by Thioflavin T (ThT) fluorescence and atomic force microscopy. Short, worm-like β-LG fibrils with an average length of 160.10 ± 50.42 nm were formed in CP-3 after 16 h of fibrillation time, whereas long, rigid, straight fibrils with an average length of 1344.00 ± 1075.67 nm were generated in AT (AFs prepared by conventional acidic heat treatment). Further antigenicity analysis revealed an 80.25 ± 1.67% reduction in antigenicity of β-LG was obtained in CP-3 after 16 h of fibrillation time, compared with a 62.95 ± 0.21% reduction in AT, as confirmed by Western blotting and enzyme-linked immunosorbent assay (ELISA). Additionally, CP-induced AFs exhibited improved emulsifying properties comparable to those produced by acidic heating, despite differences in fibril morphology and viscosity.