该研究以单硬脂酸甘油酯（GMS）基油凝胶和黄原胶基水凝胶构建油包水型双凝胶结构将植物乳杆菌包封在内部水相。通过改变GMS含量对双凝胶体系结构进行调控，对其微观结构、力学性质、流变特性进行表征，通过模拟体外消化实验探究该体系对益生菌活性的保护作用。研究表明，增大GMS添加量，双凝胶样品的均匀性、抗应力性、结晶度和体系稳定性提高，但GMS添加量高于10%时，体系稳定性有所下降。模拟体外胃肠消化发现，将益生菌包埋在双凝胶体系内部水相位置，经胃肠消化后，游离益生菌样品未检测到活性，包埋体系中益生菌数量均高于7.5 log CFU/g。胃肠消化后活菌数以及其在小肠中的释放量随着GMS含量增加产生变化，其中GMS含量较高的样品中益生菌胃肠消化活性和释放量均较高。这说明调节双凝胶体系中GMS含量可调控包埋物质益生菌的活性并且增加其在肠道中的释放特性。该研究为益生菌递送体系和功能性食品的开发提供理论依据。

A water-in-oil bigel structure was constructed with a glycerol monostearate (GMS)-based oleogel and a xanthan-gum-based hydrogel to encapsulate Lactobacillus plantarum in the internal aqueous phase. The structure of the bigel system was modulated by changing the concentration of GMS. The microstructure, mechanical properties, and rheological properties of the system were characterized. The protective effect of the system on the viability of probiotics was explored through simulated in vitro digestion experiments. The results showed that the homogeneity, stress resistance, crystallinity, and system stability of the bigel samples improved with increasing GMS concentration; however, the system stability decreased when the GMS concentration exceeded 10%. After gastrointestinal digestion in the simulated in vitro gastrointestinal digestion experiments, no viable probiotics were detected in the free probiotics samples, while the counts of viable probiotics were higher than 7.5 log CFU/g in all samples with probiotics embedded in the aqueous phase of the bigel system. The count of viable probiotics after gastrointestinal digestion and their release in the small intestine varied with the GMS concentration, with higher probiotic viability and release in samples with higher GMS concentrations. These results suggest that regulating the GMS concentration in the bigel system can modulate the viability of the embedded probiotics and their release in the intestine. This study provides a theoretical basis for the development of probiotic delivery systems and functional foods.

国家自然科学基金项目（31972002）；区域创新发展联合基金重点支持项目（U21A200270）