Tributyrin microcapsule prepared by ultrahigh methoxylated pectin combination with maltodextrin: The characterization, gastrointestinal digestion, and fecal fermentation behavior

A modified ultrahigh methoxylated pectin (UHMP, DM>90%) combined with maltodextrin was used to prepare tributyrin microcapsules. The encapsulation performance of microcapsules and their potential application in gut health were investigated in this study. Results showed that tributyrin was successfully encapsulated into the matrix of microcapsules, and there is no extensive chemical reaction occurred during encapsulation. The UHMP is conducive to the dispersion of tributyrin, while the maltodextrin as wall material promoted the formation of smooth surface structure of microcapsules. Microencapsulation is able to provide thermal protection for tributyrin, as reflected by the increased decomposition temperature and the decreased weight loss rate. In addition, microencapsulation effectively masks the unpleasant odor of tributyrin, resulting in a significantly reduced off-odor retention rate. During small intestinal digestion, the UHMP-stabilized tributyrin emulsions partly demulsified and led to the release of tributyrin, however, a significant higher tributyrin retention rate (88.1 ± 1.3%) was observed in UHMP-stabilized tributyrin emulsions when compared with the blank group (60.1 ± 4.6%). Through in vitro fecal fermentation, it was found that UHMP-stabilized tributyrin emulsions can regulate bacterial community by stimulating the growth of probiotics (e.g. Lachnospira, Phascolarctobacterium, and Parabacteroides) and decreasing the relative abundances of harmful microbes (e.g. Klebsiella and Fusobacterium). Furthermore, UHMP-stabilized tributyrin emulsions promote the production of SCFAs, especially, the content of butyric acid increased from 1.59 ± 0.32 mmol/L to 10.58 ± 1.89 mmol/L. The present study provides a feasible approach for the preparation of tributyrin microcapsule, which improves its application performance in gut health.