Isolation Of Function Microorganism In The Mud Pit And The Research Of Application For The DYH-1 Pit Solution

As an important function microorganism in the mud pit, Caproic acid bacteria and butyric acid bacteria plays an important role in the formation of liquor's flavor. In the process of brewing, alcoholic fermentation and formation of esters cannot succeed without the help of yeast. The study on the growth and fermentation characteristics of these function microorganism isolated can provide some guidance for daily production. The fermentation characteristics of each Caproic acid bacteria and butyric acid bacteria, the role of the yeast mixture and complex ratio and the application in Enhanced the new pit were discussed in this paper. The main results are as follows:1. A new strain of butyric acid bacteria and Caproic acid bacteria was isolated from aged pit mud of Daohuaxiang Distillery. The former has a single fermentation acid production capacity of around 250mg/100mL, named BLT-B03 strain. The acid production capacity of the latter was 300mg/100mL, named BLT-B02 strain. The best conditions of their acid production: temperature is around 36℃, pH7.0.2. Under the existence of ethanol and acetate, BLT-B02 has a weak fermentation capacity for Caproic acid. When BLT-B02 inoculated with the appropriate ratio and mixed BLT-B03 fermentation, it can effectively promote acid production of Caproic acid. It Strains with the BLT-B03 inoculation ratio of 1:1, which can have a 50% increase acid production3. Yeast strains selected on the BLT-B03 strain has a good ability of esterification. The optimum reaction temperature is about 30℃, pH5.0 6.0, 2% ethanol content and yeast addition level of 10% to 15%. Yeast can effectively promote acid production of the BLT-B03 strain. Under the conditions of 90% liquid volume, the mixture of acid production has a single 20% increase in the fermentation capacity. With 40% portion of liquid and an appropriate amount of glucose, BLT-B03 in the medium supplemented can effectively improve the activity of yeast. The optimum dosage is 2%, which can help the acid production increased by 70% without glucose.4. The single factor experiment showed:Temperature and initial pH have important impacts on the strain. The addition of yeast and glucose also affect a lot on the remix. Therefore the BLT-B02 and BLT-B03 strain as the starting strain with ratio of 1:1 in the complex conditions, Orthogonal test L₉(3⁴) which take the temperature, initial pH, glucose amount and the amount of yeast as the 4 key factors was carried out. Determine the optimal solution is: the yeast mixture of 15% addition level, addition of 2% glucose, initial pH 5.5, culture temperature 36℃.5. The experiment used the BLT-B02, BLT-B03 and yeast complex bacterial liquid as the supporters for the DYH-1 pit solution, and the new pits strengthen. The results of experiment showed that the remix bacterial liquid can create a better environment in the microbial growth pool for the new pits , which can increase the number of the function microorganisms, elevate both the quality and output of the produced liquor. With the strengthened new pits, the liquor production capacity has been raised almost 10 years of age old pits pit level.