Pickering高内相乳液制备及其稳定性与消化特性研究

Stability and Digestion Characteristics of Pickering High Internal Phase Emulsion Formed by 7S and 11S

摘要:

利用大豆球蛋白（11S）和β-伴大豆球蛋白（7S）在酸性条件下制备Pickering高内相乳液，通过粒径、ζ-电位、傅里叶红外光谱（FITR）、冷冻扫描电镜、乳化性和流变学等研究其稳定性，并探讨其消化特性。结果表明：在pH值2.0时，7S和11S形成的乳液均具有较高的乳化活性和乳化稳定性，11S比7S具有更高乳化性能。当蛋白质量浓度为0.015g/mL，油相体积分数为78%~82%时，可以形成稳定的高内相乳液。通过增加内相体积分数，7S和11S蛋白颗粒稳定的Pickering乳液体系分布更加均匀，不易发生聚集，并且可以形成较强的凝胶网络结构。模拟体外消化实验表明，在酸性条件下，蛋白形成的高内相乳液可以不同程度地延迟脂质的释放。本研究明晰了在酸性条件下7S和11S的结构特性以及7S和11S高内相乳液在胃肠道中的消化行为，可为食品功能性成分递送体系研究提供理论支撑。

Abstract:

Pickering high internal phase emulsion was prepared by using soybean globulin (11S) and soy β-conglycinin (7S) under acidic conditions. The stability of the emulsion was studied by particle size, potential, Fourier transform infrared spectroscopy（FITR）, freeze scanning electron microscopy, optical microscopy and rheology, and its digestion characteristics were also discussed. The results showed that when pH value was 2.0, the emulsion formed by 7S and 11S had higher emulsifying activity and emulsifying stability, and 11S had higher hydrophobicity and emulsifying property than 7S. When the protein concentration was 0.015g/mL and the volume fraction of oil phase was 78%~82%, stable high internal phase emulsion can be formed. By increasing the volume fraction of the internal phase, the emulsion system with stable 7S and 11S protein particles distributed more evenly and was not easy to aggregate, which enhanced the formation of gel network. Compared with 7S stabilized Pickering high internal phase emulsion, 11S formed a stronger gel network structure with stronger gel strength and more stable emulsion system. Simulated in vitro digestion experiments showed that under acidic conditions, the particle size and potential value of the emulsion were lower, and the fat release was less. The high internal phase emulsion formed by the protein could delay the release of lipid to varying degrees. The research result clearly identified the structural characteristics of 7S and 11S under acidic conditions and the digestive behavior of stable high internal phase emulsions in gastrointestinal tract, and provided theoretical support for the research and development of food functional ingredient delivery system.