探究不同二十碳五烯酸（Eicosapentaenoic Acid，EPA）和二十二碳六烯酸（Docosahexaenoic Acid，DHA）组成比例的鱼油乳液的体外消化特性。制备不同EPA/DHA（5.13、2.45、1.34）比例的O/W鱼油乳液，对消化过程中粒径、ζ-电位、微观结构及小肠阶段脂肪酸的释放行为进行研究。结果表明，不同EPA/DHA比例的鱼油乳液在消化过程中的变化趋势相似，同时各乳液消化特性有所区别。具体而言，三种初始乳液均具有较高的稳定性，电荷性介于-40.02 mV和-43.77 mV，粒径主要分布于0.1~1.0 μm之间。经口腔与胃阶段消化后，各体系电荷绝对值显著降低（P<0.05），乳滴中心脂质暴露，粒径呈多峰分布且主要集中于10~100 μm区间。小肠阶段各组乳液粒径显著降低至8~13 μm（P<0.05），游离脂肪酸（Free Fatty Acids，FFA）相对释放结果表明，EPA/DHA=5.13组乳液（103.21%）>EPA/DHA=2.45组乳液（73.54%）>EPA/DHA=1.34组乳液（62.51%），EPA与DHA相对水平是影响三种鱼油乳液消化的重要因素。该研究可为富含EPA与DHA的海洋脂类膳食摄入及鱼油递送系统的开发设计提供一定参考。

To investigate the in vitro digestive properties of fish oil with different proportions of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), based on an in vitro gastrointestinal digestion model (GIT), O/W fish oil emulsions with different ratios of EPA/DHA (5.13, 2.45, and 1.34) were prepared. The changes in the particle size, ζ-potential, and microstructure during digestion, as well as the release behavior of fatty acids during digestion in the small intestinal, were investigated. The results showed similar variation trends for fish oil emulsions with different EPA/DHA ratios. Despite this, each emulsion exhibited unique digestive characteristics. Specifically, all three initial emulsions showed higher stability, with strong negative charges, ranging from -40.02 to -43.77 mV, as well as relatively uniform particle size distributions (0.1-1.0 μm). After oral and gastric digestion, the absolute value of charge of each system decreased significantly (P<0.05), exposing the inner lipid phase. In addition, particle size was found to follow a multi-peak distribution and was mainly concentrated in the range of 10~100 μm. During small intestine digestion, the particle size of each system decreased significantly to 8-13 μm (P<0.05). The release of the free fatty acids (FFA) was 103.21% (EPA/DHA ratio of 5.13), 73.54% (EPA/DHA ratio of 2.45), and 62.51% ((EPA/DHA ratio of 1.34). These results suggest that the relative proportion of EPA and DHA is an important factor influencing fish oil emulsion digestion. This study provides a basis for the determination of the recommended daily EPA and DHA-rich marine lipid intake and the design of fish oil delivery systems.

广东省基础与应用基础研究基金项目（2020A1515110263）；国家自然科学基金青年项目（32101958）；广东省农业科学院科技人才引进专项资金项目（R2021YJ-YB3005）；广东省天然产物绿色加工与产品安全重点实验室项目（202211）；广东省重点研发计划项目（2021B0202060001）；广东省农业科学院协同创新中心（XT202303）；梅州市科技计划项目（2021A0107003）；2020 年青年导师制项目（R2020QD-041）