Multi-modified β-Lg-stabilized fish oil emulsions: physicochemical stability, antioxidant capacity, and bioavailability in Caco-2 cells

Effect of prior hydrolysis and subsequent 36 h glycation on the ability of amyloid-like fibrils derived from β-Lactoglobulin (FG 36 Hβ-Lg) to provide physicochemical stability to fish oil emulsions was systematically determined under varying pH, ionic strength, thermal, and storage conditions. In vitro digestion studies coupled with a Caco-2 cell model investigation evaluated the emulsions' cellular uptake, transmembrane transport, and antioxidant properties. GC–MS analysis of the post-digestion micellar phase revealed that emulsification enhanced the apparent permeability of eicosapentaenoic acid (EPA). FG 36 Hβ-Lg conferred superior EPA transport efficiency and the strongest cellular antioxidant effects on emulsions, compared to proteins modified by hydrolysis or glycation alone, or lacking fibrillar structure. Parallel reaction monitoring showed that FG 36 Hβ-Lg emulsions upregulated key regulatory proteins involved in lipid metabolism and inflammation, such as HMGCR and NFKB1. These findings demonstrate that modified β-Lactoglobulin fibrils improved physical and oxidative stability of emulsions and show promise to enhance bioavailability of omega-3 fatty acids.