共轭亚油酸（CLA）是一类具有多种生理活性的不饱和脂肪酸，极易被氧化，在食品工业中的应用受到很大限制。本文采用阿拉伯胶（GA）制备CLA乳液，从CLA氧化产物角度来评价GA对CLA乳液的氧化保护作用，同时对CLA在模拟胃肠中的释放动力学特征进行研究。结果表明，5.0%浓度时GA在乳液界面荷载量达到最大，此浓度下乳液中CLA的挥发性氧化降解产物浓度最低，氧化稳定性最好；在模拟胃液中释放率缓慢增加，粒径分布均匀；在模拟肠液中释放率加快，乳液出现大颗粒聚集。随着GA浓度增加，CLA挥发性氧化降解产物含量增加，氧化稳定性降低；CLA在胃部释放率有所增加，大颗粒聚集增多。但总体来说，GA乳液中CLA在模拟胃肠液中的释放显示出了良好的营养缓释性能，延长了CLA的释放时间，提高了CLA的生物利用度。

Conjugated linoleic acid (CLA) is an unsaturated fatty acid with many physiological activities. Since it can be easily oxidized, its application in the food industry was greatly limited. A CLA emulsion was prepared using gum arabic (GA), and the protective effect of GA against oxidation of CLA emulsion was evaluated in terms of the oxidative degradation products, and the characteristics of the release kinetics of CLA encapsulated by GA emulsion in simulated gastrointestinal juice were also investigated. The results showed that the surface loading of GA was the highest in the emulsion stabilized with 5% GA. Moreover, at this concentration, the lowest concentrations of volatile oxidative degradation products of CLA in the emulsion were found, and the optimal oxidative stability was presented. In addition, the release rate of CLA in emulsion in the simulated gastric juice slowly increased with homogeneous particle size distribution, while the release rate was accelerated in intestinal juice with aggregation of large particles in emulsion. With increasing concentration of GA, the content of the volatile oxidative degradation products of CLA increased, and the oxidative stability decreased. Furthermore, the release rate of CLA in gastric juice increased to some extent, along with the increase in large particle aggregation. Thus, CLA encapsulated in GA emulsion exhibited the properties of sustained nutrition release, extended release time, and enhanced bioavailability in simulated gastrointestinal juice.

国家自然科学基金资助项目（31470096；31101260；31322043；31171751）；湖北省自然科学基金（2014CFB602）；湖北省高等学校优秀中青年科技创新团队计划（T201307）；湖北工业大学博士启动金（BSQD12050）