Polyphenol-modified ovalbumin-lysozyme heteroprotein microcapsules: A complex coacervation approach for enhancing probiotic viability

Probiotics are susceptible to environmental factors during processing, storage, and digestion, which greatly limits their beneficial effects. This study constructed and characterized polyphenol-modified ovalbumin-lysozyme (OVA-LYS) complex coacervates and evaluated their stability as probiotic delivery carriers during environmental stresses and gastrointestinal digestion. The results demonstrated that the coupling of catechin (C), epicatechin (EC), and epigallocatechin (EGC) with heteroprotein enhanced the complexes structure, and the probiotic microcapsules showed favorable properties in terms of physicochemical properties. Notably, C-HPCC microcapsules were more effective in encapsulating probiotics (99.43 %). Furthermore, the protection efficiency of microcapsules treated with heating, storage, and digestion consistently followed C-HPCC > EC-HPCC > EGC-HPCC > HPCC order, which was attributed to the stronger affinity between C and heteroprotein. Finally, a novel flavored fermented milk with multiple functions was formulated using probiotic microcapsules as fermentation agents. Overall, this research provided valuable inspiration for novel functional food development with higher bioavailability.