The Incorporation of Plant-Derived Polysaccharides into Alginate-Based Capsules Improve Probiotic Viabilities During Storage, Gastrointestinal Digestion, and Their Application in Yogurt

The objective of this research was to combine three plant-derived polysaccharides, <i>Lycium barbarum</i> polysaccharides (LBP), peach gum polysaccharide (PGP), and citrus pectin (CP), with alginate (SA) to co-encapsulate probiotics and investigate the survival of cells during in vitro gastrointestinal digestion, storage, and application in yogurt. The incorporation of different polysaccharides into SA all improved the encapsulation efficiencies and surface regularities of probiotic capsules. Texture analysis showed that the PGP-incorporated microspheres exhibited the highest values for hardness, springiness, and resilience, while in terms of chewiness, the highest values were observed for the LBP and CP groups. In vitro gastrointestinal digestion analysis revealed that the incorporation of different polysaccharides all further enhanced the cell survival rates, and the SA: PGP group demonstrated superior probiotic protection with the minimal viability loss of only 0.40 log CFU/g after 6h digestion. During storage, SA: PGP group also exhibited the highest stability, which still maintained 7.7 Log CFU/g of viable cells at the end of 20 days storage, and after incorporation of SA: PGP into yogurt, 7.8 Log CFU/g of viable cells were still detected at the end of 21 days storage.