Abstract:In this study, we prepared an interface-dominated food foam system via regulating the interactions between macromolecules and small molecules. For the first time, food-grade glycerol was used as a green co-solvent to dissolve the hydrophobic gliadin and amphiphilic small-molecule tea saponins (TS). The interaction between gliadin and tea saponin as well as its foam-forming ability and stability were further evaluated. Intrinsic fluorescence spectroscopy measurements revealed that the fluorescence quenching parameter was 1.345×109 M-1 S-1, which was much smaller than the maximum dynamic quenching constant (2×1010 M-1 S-1). These findings indicated that TS-mediated dynamic quenching enabled the formation of a complex system via the non-specific hydrophobic interactions prior to the formation of foam. The results of dynamic adsorption at the interface showed that at a suitable TS concentration (0.5%~0.75%), the gliadin-TS interaction could increase the interfacial activity and coverage area, compared with gliadin or tea saponin. Confocal laser scanning microscopy showed that at the above-mentioned TS concentrations, gliadin was accumulated on the foam surface, leading to a foam containing small-sized air bubbles, and eventually a gliadin-TS system with foam-forming ability and stability.
