Enhancing viability of Lactobacillus plantarum encapsulated by alginate-gelatin hydrogel beads during gastrointestinal digestion, storage and in the mimic beverage systems

To improve the viability of Lactobacillus plantarum (P) during digestion and storage, the probiotics were encapsulated by alginate (ALG) and alginate-gelatin (ALG-GE) hydrogels beads. ALG-P-GE showed much better physicochemical properties than ALG-P. The scanning electron microscopy (SEM) results validated the incor-poration of bacterial cells into the beads. ALG-P-GE exhibited good encapsulation efficiency of 97.7 %, and the storage and thermal stability of probiotic were increased by 15 % and 8 %, respectively, when comparing with ALG-P. ALG-P-GE beads could protect the probiotics from inactivation in simulated gastric fluid and then release it in simulated intestinal fluid. The protective mechanism of ALG-GE for probiotics was further studied by fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and found that ALG and GE can form gel network through hydrogen bonding and electrostatic interactions. In the mimic beverage systems, ALG-P-GE beads could protect the encapsulated probiotics and increase its viability. The storage, thermal, and digestion stability of encapsulated probiotic were significantly increased and showed high viability in the mimic beverage systems. ALG-P-GE beads have great potential for the protection and delivery of probiotics in food systems.

Automated summary

In order to enhance the survival of Lactobacillus plantarum (P) during digestion and storage, probiotics were encapsulated in alginate (ALG) and alginate-gelatin (ALG-GE) hydrogel beads. The physicochemical properties of ALG-P-GE were superior to that of ALG-P. The inclusion of bacterial cells in the beads was confirmed by scanning electron microscopy (SEM). ALG-P-GE exhibited a high encapsulation efficiency of 97.7% and improved storage and thermal stability of the probiotic compared to ALG-P. The ALG-P-GE beads protected the probiotics from inactivation in simulated gastric fluid and released them in simulated intestinal fluid. The protective mechanism of ALG-GE for probiotics was further studied using fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD), which revealed gel formation through hydrogen bonding and electrostatic interactions between ALG and GE. In mimic beverage systems, ALG-P-GE beads effectively protected the encapsulated probiotics and improved their viability. The encapsulated probiotic showed significantly increased storage, thermal, and digestive stability, indicating the great potential of ALG-P-GE beads for the protection and delivery of probiotics in food systems.