Enhancing probiotic viability: Impact of soy hull polysaccharide concentration on stabilized high-internal-phase emulsions encapsulated with Lactobacillus plantarum and their release during gastrointestinal digestive

Abstract

This study investigated the impact of soy hull polysaccharide (SHP) concentration on the formation of high-internal-phase emulsions (HIPEs) stabilized with soy protein isolate (SPI), encapsulated with Lactobacillus plantarum, and explored its gastrointestinal digestive mechanism. The results of Zeta potential, particle size and rheological properties revealed the excellent viscoelastic and thermal stability of the HIPEs. Compared to free probiotics, the in vitro digestion of probiotics encapsulated with 1.8% SHP HIPEs demonstrated a significant improvement in activity, with an encapsulation efficiency of 71.1%. Throughout the three stages of Gastrointestinal Tract (GIT) digestion, HIPEs maintained robust stability during the gastric digestion phase. Subsequent to trypsin enzymolysis, interactions between –NH3+ and –COOH led to binding and aggregation, initiating the collapse of HIPEs' structure. Concurrently, the hydrolyzed SHP and SPI formed small molecules of that further combine and flocculate. This critical juncture resulted in the release of L. plantarum into the simulated colonic environment. These findings proposed a promising strategy for employing HIPEs-encapsulated probiotics as targeted delivery systems in food applications.