Study On Microencapsulation Technologies And Their Characteristics For Lactobacillus Plantarum LIP-1

Probiotics have drawn a great degree of attention from scientists, food manufacturers and consumers, because they can confer health benefits on the host and improve the level of health care. In order to offer probiotic health benefits, they must remain viable in food products until the time of consumption. The survival and efficiency of probiotic bacteria is influenced by several factors such as:strains of probiotic bacteria and microbial interactions, pH and hydrogen peroxide, molecular oxygen, heat treatment during the process, and storage temperature and host digestive system (gastric acid, bile salt, enzyme) and so on. In this paper, probiotic Lactobacillus plantarum LIP-1 was microencapsulated in milk protein matrices by means of rennet induced gelation combined with emulsification technique. The optimum technologies for the preparation and the characteristics of microencapsulated Lactobacillus plantarum LIP-1 were investigated. The main conclusions were showed as follows:The selection of water oil ratio was 1:10, emulsifying time was 10 min, the stirring speed was 600rpm/min, skim milk concentration was 35%, so the embedding rate was 86.59%. And in microscope observation, microcapsule form was more complete, smooth and spherical. Particle size was smaller and approximately ranged from 30μm to 70μm, the distributions were more concentrated.Lactobacillus plantarum LIP-1 microcapsules in intestinal 90 min can be fully released. After artificial gastric juice digestion pH2.090 min, microcapsule of Lactobacillus plantarum LIP-1 survival rate was significantly better than the non-encapsulated in blank control group, their survival rate were 47.33% and 16.01%.On the basis of the above experiment, microcapsule of freeze drying, the survival rate of Lactobacillus plantarum LIP-1 was significantly higher than the control group, their survival rate were 63.10% and 37.18%. Milk protein has good protective effect on microcapsules. In the experiment of different temperature storage stability of microcapsules, the initial number of live bacteria was 4.93×107CFU/g, the microcapsules at 4℃ and 20 ℃ sealed and stored for 21 days, viable counts were more than 107CFU/g; after 21 days storage sealed in 37 ℃, Lactobacillus plantarum LIP-1 microcapsules live number was only 9.01×102CFU/g.The above results showed that, the use of milk protein as raw material, through the microcapsule prepared by internal emulsification can significantly improve the probiotic...