Biphasic-gelled W/O/W emulsion gel for co-delivering vitamins B₁₂ and E: Preparation, characterization, and in vitro...

This study aimed to enhance the stability and functional properties of W/O/W emulsions through a biphasic gelation strategy. An emulsified gel system was constructed with soybean lipophilic protein-chitosan hydrochloride complex (SLP-CHC) as the emulsifier, beeswax as the oil-phase gelling agent, and curdlan/anhydrous calcium chloride as the aqueous-phase gelling agent. The microstructure and physicochemical properties were characterized, and in vitro digestion experiments were conducted to evaluate the protective and delivery capacities for vitamin B₁₂ (VB₁₂) and vitamin E (VE). The biphasic gel exhibited a dense network, high viscoelasticity (G' > G"), and superior water/oil-holding capacity. Encapsulation efficiencies reached 95.92% for VB₁₂ and 69.51% for VE, with enhanced stability under heat and pH stress compared to single-phase gels. In vitro digestion confirmed effective gastric protection and intestinal release, leading to high bioaccessibility for both vitamins. This study provides a novel approach for the co-delivery of polar and non-polar bioactive compounds.