Studies On Solid-State Fermentation Process And Drying Of Lactobacillus Casei

Antibiotics in promoting animal growth, prevention and treatment of animal diseases have a significant effect, prolonged use of antibiotics will produce a strong resistance to pathogens, and it will cause endogenous infections and dual problems such as infection. Worldwide has control the use of antibiotics and the use scope, Europe and other countries even ban the use of antibiotics. While, the probiotics as a substitute for animal’s antibiotics, is a kind of non-toxic, no side effects, no residue of the new green feed additive, it can promote animal growth, combating animal diseases and improve animal gastrointestinal tract environment, so it has a wide range of applica-tions prospects.In this paper, according to the biological characteristics of Lactobacillus casei, the experiment are conducted respectively from four aspects, including improving the biomass of solid-state fermentation, dried resistance, amplification and bacteria agent storage. Specific research results are as follows:1. By adding a carbon source in the original optimized medium, it can significantly improve the solid-state fermentation of Lactobacillus casei biomass. After adding20%trehalose, the number of wet material living bacterium can reach2.0x1010CFU/g, compared with before, it increased by233%.2. Lactobacillus casei drying resistance research: Lactobacillus casei desiccation tolerance optimal incubation temperature was42℃,40℃convection drying, agents at8%moisture content, the number of viable cells highest survival rate, reaching18.7%. Contrast whole culture and fermentation medium heat alternating temperature,42℃under Lactobacillus casei improved resistance to drying capacity is mainly due to its mid-logarithmic growth for cultivation of high temperature. Lactobacillus casei identified best protective anti-drying agent is0.01%manganese sulfate plus20%trehalose, was added in the initial fermentation, after fermentation and drying, the water content of8%of the agents, the number of viable up to2.5×109CFU/g, lower than before the same moisture content increased by108%, compared with a single manganese sulfate, trehalose were increased46%and6%.Dried excipients added technology research shows that adding protective agent in fermentation, wet material with Celite1:3mixing, drying, moisture content of8%in the agents, the number of viable cells reached2.0×108CFU/g, compared with the same moisture content before optimization under increased by66.7%, compared with a single material decreased by20%, but the survival rate of Lactobacillus casei from12.5%to40%and fermentation production increased300%, greatly improving the fermentation economy.3. Experimental results show that the5Kg level consistent with40g experimental level, whether it is wet or dry materials are expected to maintain a high number of bacteria, a single material, respectively2.0×1010CFU/g and2.6×109CFU/g, respectively, mixed materials6.6×109CFU/g and2.0x109CFU/g. Agents preservation results show that solid-state fermentation bacterium Lactobacillus casei under seal preserved at28℃for30days, number of viable cells mixed materials7.2×108CFU/g, the survival rate was36.8%; single material number of viable cells1.1×109CFU/g, the survival rate was43.6%. The results are useful for further studies as well as the actual production practice has a certain significance.