Synergetic effects of whey protein isolate and naringin on physical and oxidative stability of oil-in-water emulsions

The effects of naringin on the physical and oxidative stabilities of native and heated whey protein isolate (WPI) stabilized corn oil-in-water emulsions were systematically investigated. The results showed that formation of stable WPI-naringin complex was through hydrophobic interactions via observing the increased naringin content and declined fluorescence intensity. Meanwhile, a strong interaction between heated WPI and naringin was also confirmed by fluorescence spectra. Compared with the native WPI-naringin complex, the heated WPI-naringin complex have much improved physical stability, reflected by against lower pH and 0.5 M NaCl content and an ideal thermal storage stability at 45 degrees C, and antioxidative stability with reducing lipid oxidation products. This enhanced property could be contributed to the targeted accumulation of naringin at the interface which confirmed by the higher interfacial naringin distribution. The current study provides that heated WPI-naringin complex can be used as a novel emulsifier with super physical and antioxidant activity.