蛋白质-淀粉-多酚复合颗粒调控胃肠道环境下乳液中多不饱和脂肪酸氧化稳定性的作用机制

多不饱和脂肪酸（PUFAs）是常用食品营养强化因子，在消化过程中易氧化。水包油（O/W）乳液是食品中PUFAs常用载体，研究表明蛋白质-多糖-多酚复合颗粒制成的O/W乳液明显提高生产和贮运条件下PUFAs氧化稳定性，但其对消化过程中PUFAs氧化抑制研究则刚起步。本项目以大豆蛋白（SP）、辛烯基琥珀酸酯淀粉（OSAS）、表没食子儿茶素没食子酸酯（EGCG）为原料，首先，通过改变环境条件、组装顺序制备不同类型的SP-OSAS-EGCG复合颗粒，表征其结构和性质，明确其形成规律；然后，研究模拟胃肠道环境下复合颗粒在PUFAs乳液界面的吸附规律，解析复合颗粒对乳液界面稳定性的影响机制；最后，评价模拟胃肠道环境下PUFAs乳液的氧化稳定性，明确复合颗粒结构与PUFAs氧化稳定性的构效关系，揭示复合颗粒提高乳液中PUFAs氧化稳定性的作用机制，为开发安全、营养的含PUFAs类功能食品提供理论依据。

Polyunsaturated fatty acids (PUFAs) are common nutritional fortifiers in food. However, PUFAs are susceptible to oxidizing during digestion. Oil-in-water (O/W) emulsions are common carriers for PUFAs in foods. It is found that the oxidation stability of PUFAs was improved significantly in O/W emulsions stabilized by protein-polysaccharide-polyphenol particles under the conditions of food production, storage and transportation. However, studies on the inhibition of PUFAs oxidation during digestion are very few. In this project, soy proteins (SP), octenyl succinate starch (OSAS), epigallocatechin gallate (EGCG) are used as raw materials. First, different types of SP-OSAS-EGCG particles were prepared by changing the environmental conditions, and self-assembly order. Their structures and properties were characterized, and their formation mechanism were clarified. Secondly, the adsorption properties of SP-OSAS-EGCG particles at PUFAs emulsion interfacial in simulated gastric and small intestine environments were studied, and the effects of the particles on emulsion interfacial stability were analyzed. Finally, the oxidation stability of PUFAs emulsions under simulated gastrointestinal environment was evaluated. The structure-effect relationship between the particle structure and the PUFAs oxidation stability in the gastrointestinal environment was established, and the mechanisms of particles improving oxidation stability of PUFAs in O/W emulsion were revealed. These studies will provide a theoretical basis for the development of safe, nutritious polyunsaturated fatty acid functional foods.