Abstract: Objective:Taking probiotic Lactobacillus paracasei R8 as the research object, the key technological parameters of double-layer embedding were studied to improve the stability of the bacteria and achieve the goal of directional release in the intestine. Methods:In this study, freeze-dried protectants and prebiotics were screened, the concentration of sodium alginate and calcium chloride were optimized, and the release characteristics of the microcapsules in artificial gastric juice and artificial intestinal juice were detected an analyzed. Results:The optimum freeze-drying protectant was 20% whole egg liquid, inulin was the best probiotic. The optimum embedding liquid formula was:5% probiotic, 2% inulin, 20% whole egg liquid, 1% sodium alginate. The optimum solidifying liquid formula was 2.5% calcium chloride. The microencapsulated particles were able to tolerate gastric juice damage and were released within 45 min in simulated intestinal environment. The number of viable bacteria in artificial intestinal fluid was 65.6% of the original microencapsulated bacteria.The whole egg liquid played a protective role in the preparation process and improves the stability in the storage process. The cell/protein/sodium alginate microcapsules could be further coated with chitosan material to realize directional release in the intestinal tract.