Metal-polyphenol network-coated probiotic microcapsules: Enhancing Limosilactobacillus fermentum storage stability and yogurt characteristics

MPNs with four polyphenols enhanced coating stability and polyphenol adhesion. • Coating traits linked to molecular size and hydroxyl group number. • Encapsulated L. fermentum CYH-108 improves yogurt fermentation and storage quality. • Microcapsules construct a more stable yogurt protein gel network. • Mechanism of microcapsules regulating probiotics and quality is partially clarified. Probiotic stabilization was achieved by microencapsulation using metal ion-coordinated self-assembly. Limosilactobacillus fermentum (LF) were encapsulated within metal-polyphenol networks (MPNs) constructed from tannic acid (TA), gallic acid (GA), epigallocatechin (EGC), epigallocatechin gallate (EGCG) and Fe 3+ . MPN deposition on bacteria was evidenced by adhesion rate, size, zeta potential, and TEM imaging. The encapsulation exhibited negligible cytotoxicity while imposing controlled suppression on their growth. In yogurt, the microcapsules mitigated the rate of pH reduction and enhanced bacterial survival during freeze-drying and storage. Yogurt supplemented with EGCG@L accumulated the highest concentrations of organic acids. Instrumental flavor analysis revealed an altered volatile profile in microcapsule-fortified yogurt. The MPN coating formed a crosslinked protective membrane. EGCG and TA showed superior coating stability and probiotic protection. This study demonstrates MPN application in functional probiotic yogurt, reveals the intrinsic stabilization mechanisms, and guides polyphenol selection for probiotic coating. Created with BioGDP.com . Download: Download high-res image (323KB) Download: Download full-size image