本研究通过调控大分子-小分子相互作用构建界面主导的食品泡沫体系，首次利用食品级甘油作为绿色共溶剂溶解疏水性小麦醇溶蛋白和两亲性小分子茶皂苷，进一步研究和评估了蛋白-茶皂苷复合体系的相互作用及其泡沫形成和稳定能力。内源荧光光谱分析荧光猝灭参数为1.345×109 M-1 S-1，其远远小于最大动态猝灭常量（2×1010 M-1 S-1），说明由茶皂苷介导的动态猝灭可促使蛋白与茶皂苷通过非特异性疏水相互作用形成复合体系。通过界面动态吸附结果可知，与单纯的小麦醇溶蛋白或茶皂苷相比，蛋白-茶皂苷复合体系在适宜的茶皂苷浓度（0.5%~0.75%）下可通过两者在气-甘油界面的相互作用增强界面活性及覆盖面积。激光共聚焦图片显示在上述茶皂苷浓度下小麦醇溶蛋白富集在气泡表面，可形成尺度更小的泡沫，最终提高小麦醇溶蛋白-茶皂苷复合体系的起泡能力和泡沫稳定性。

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.

国家自然科学基金项目（31771923）