Abstract: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.
