Flavonoids enhance gel strength of ovalbumin: Properties, structures, and interactions

The effect of ovalbumin-flavonoids (naringenin, genistein, naringin, puerarin, and daidzein) interactions on the formation and properties of ovalbumin hydrogels was investigated. The results suggested that flavonoids were able to promote the gelation of low concentration ovalbumin solution, which was not able to form hydrogel upon heating. All hydrogels formed by flavonoids and ovalbumin were more elastic than viscous. The hydrogels formed by naringenin and ovalbumin showed the strongest gel hardness, springiness, and water holding capacity. Fluorescence spectroscopy and molecular docking analysis revealed that the main interactions between ovalbumin and naringenin, genistein, puerarin, naringin were hydrogen bond, while the main interaction between ovalbumin and daidzein was hydrophobic force. Flavonoids, which have a structure with more phenolic hydroxyl groups, a C2 = C3 double bond and dehydrogenated glycosides, possessed higher affinity to ovalbumin. This research provides new insights into mechanism of ovalbumin-flavonoids interactions and its influence on the formation and property of hydrogel.