Study on microencapsulation of Lactobacillus plantarum LIP-1 by emulsification method

摘要

We prepared probiotic microcapsules with lactoprotein as the wall material using an optimized emulsification method. Results of an orthogonal experiment showed that when the water-oil ratio was 1:10, the skim-milk concentration was 35% (wt/wt), the emulsification time was 10 min, stirring speed was 600 r/min, microencapsulation efficiency was 86.59%, and particle size was 52.56 mu m. The evaluation of microcapsules' performance in simulated human digestion confirmed that the microcapsules released the probiotics completely in simulated intestinal fluid within 90 min. The survival rate after exposure to simulated gastric fluid for 90 min was 53.3%, which was significantly higher than that of free cells (16.81%; p .05). The freeze-drying survival rate was 63.10%. The viability of the probiotics decreased only by 0.46 log CFU/g during storage at 4 degrees C for 21 days, benefit by microcapsules' denser structure. These results provide a theoretical reference for an industrial application of microencapsulation.Practical applications Microcapsulation technology can be applied to produce functional and healthy food containing probiotic bacteria, such as yoghurt, cheese, ice cream, and other products. Microcapsule powder can be prepared by freeze-drying as a lactic acid bacterial starter. Microcapsules are a potential drug delivery system, and Lactobacillus plantarum LIP-1 is a beneficial probiotic that lowers blood cholesterol.