Double encapsulation using sodium alginate and nano-tapioca starch combined with chitosan enhances the viability of Lactiplantibacillus plantarum ZFM4 during simulated gastrointestinal and storage conditions

Lactic acid bacteria (LAB) have exhibited great significance for the balance of gut microbial homeostasis, while most LAB show poor tolerance to human gastrointestinal (GI) conditions, limiting their effect and employment in improving gut microbiota. Herein, this study aimed to develop a double-encapsulated coating from sodium alginate, nano-tapioca starch and chitosan by sharp-hole granulation using the LAB strains Lactiplantibacillus plantarum ZFM4 ( L. plantarum ZFM4). Carried out the optimization of wall material and lyoprotectant formula, the optimized capsules demonstrated an encapsulation efficiency of 93.10 ± 0.31% and a freeze-dried survival rate of 84.71 ± 0.52% for the encapsulated cells. In vitro digestion tests showed the significant increased survival rate of encapsulated L. plantarum ZFM4 in simulated saliva (increased 6.66%), gastric juice (increased 56.88%), and pancreatic juice (increased 59.89%), with well release characteristics in simulated intestinal fluid. Additionally, the heat resistance and stability of L. plantarum ZFM4 under various storage conditions remarkably accelerated after encapsulation. Our findings suggest that this double encapsulation method effectively enhances the tolerance of L. plantarum ZFM4 under both simulated GI and storage conditions, providing a theoretical basis and technical support for its immobilization research and product development for intestinal health. • A double encapsulation was developed using sodium alginate, nano-tapioca starch and chitosan to protect probiotics. • The encapsulated L. plantarum show excellent encapsulation efficiency and viability. • Encapsulation enhanced the tolerance of L. plantarum in simulated gastrointestinal. • Encapsulation improved the thermal resistance and storage stability of L. plantarum.