The beeswax-based fish oil oleogels adjusting the stabilization mechanism and lipid digestion of bi-layer emulsions: Spatial conformation and molecular interaction

Abstract

Fish oil contains omega-3 polyunsaturated fatty acids, but their poor oxidation stability and gastrointestinal digestion rate led to the low bioavailability. Oleogels could improve the stability of EPA and DHA, so the effect of beeswax (BW)-based fish oil oleogels (FOGs) on the stabilization mechanism and lipid digestion of bi-layer emulsions was investigated. The results showed that the enhanced BW crystals lowered the myofibrillar protein (MP) unfolding along with the decrease in β-sheets, hydrophobic force and disulfide bond, thus reducing the interfacial adsorption capacity and emulsion stability. The enhanced BW formed the rigid crystal network structure and improved the crystal size in the inner layer. The suitable FOG addition (4 wt%) enhanced the unfolding of advanced structures in the outer layer, and the exposure of more hydrophobic groups and disulfide bonds facilitated the interfacial adsorption, thus reducing the size. The final release rate of FFAs significantly decreased with the increasing BW, and significantly increased and decreased with the increasing FOG. BW and FOGs could induce the changes in spatial conformation, and the exposure of hydrophobic groups and disulfide bonds affected the lipase contact at the interface. BW and FOG could adjust the crystal network structure in the inner layer and spatial conformation in the outer layer, thus improving the stabilization and lipid digestion of bi-layer emulsions. This study can provide a theoretical basis for developing DHA and EPA food.