High internal phase emulsion stabilized by sodium caseinate:quercetin complex as antioxidant emulsifier

High internal phase emulsion (HIPE) was produced and stabilized using a novel antioxidant emulsifier formed by the complexation between sodium caseinate (SC) and quercetin (Q). Colloidal complexes, produced via an alkaline process, showed great ability to reduce the interfacial tension between oil-water phases, promoting stabilization of the HIPEs even at low concentrations (1.5% w/v in the aqueous fraction). HIPEs at 0.80 volume fraction of dispersed phase presented remarkable viscosity due to the high-packing network of oil droplets surrounded by a thin liquid layer. Moreover, the emulsions showed a gel-like behavior and kinetic stability for 45-days at 25 degrees C. The approach of SC:Q complexes on HIPEs development is promising to reduce lipid oxidation, translated by the formation of hydroperoxides and malondialdehyde during storage, especially for the complex formed with the highest amount of the phenolic compound. In this study, the development of HIPEs with outstanding kinetic and oxidative stability is reported as a potential alternative for the development of healthier products with reduced saturated and trans-fat content.