Abstract
As the typical model of Chinese strong aromatic spirits, the Luzhou-flavor spirits occupy an very important position in the spirits market. The problem of inadequate fermentation of the fermented grains in the pit emission during the production of Chinese strong aromatic spirits will directly influence the generation of the fragrant matters of the spirit body. To resolve the above problem, this article develops a sort of compound microbial enzyme agent，and adds it into the fermented grains to involve in the fermentation, so as to make fermentation and produce fragrance inside the pit.
First of all, by single factor test the solid state cultivation conditions of the pit mud functional bacteria are determined, by uniform experimental design the addition level of the bacteria juice is determined, and by orthogonal test the formulae of the solid state culture medium are determined, and finally the pit mud functional bacteria are obtained by intermediate culture. For the convenience of preservation and transportation, the bacteria are processed via drying and dehydration. The number of the clostridia in the dry pit mud functional bacteria is close to that in the pit mud of eight year pit age.
Secondly, by response surface ytical method the optimal blending ratio of the compound microbial enzymes agent is obtained, which is: 0.9% dry pit mud functional bacteria, 1.5% B type enzyme promotion substance, 0.25% monascus esterified enzyme, and 0.35% aroma-producing yeast.
Finally, add the compound microbial enzyme agent into the fermented grains to take the comparison test.
The test results and yses are as follows:
① Comparing with the comparison group, the content of the hexanoic acid inside the fermented grains of the experimental group is 24mg/100g higher, the butyric acid is 13mg/100g higher, the acetic acid is 5mg/100g lower and the lactic acid is 300mg/100g lower. The ethyl hexanoate is 13mg/100g higher than the comparison group, and the changing trend of the ethyl lactate is similar to the changing trend of the lactic acid, which means the its content in experimental group is 38mg/100g lower than that in the comparison group, reaching to the aim of "increasing hexanoic acid and decreasing lactic acid ".
②The guideline for the samples of the distillate spirits: no big difference in the alcohol yield, but in respect of the mouthfeel the samples of the experimental group are better than those of the comparison group. The results of the gas chromatographic yses show that the content of the organic acid is within the normal range, but by comparing with the comparison group the volume of the ethyl hexanoate in the samples of the experimental group is 1g/l higher, the volume of the ethyl lactate is 0.4g/l lower, the volume of the ethyl acetate is 0.5g/l lower and the volume of the ethyl butyrate is not quite dfferent.
According to the tests, the compound microbial enzyme agent is fully involved in the fermentation process of the spirits, and the changes of the quantities and species of the microbes play a very important role in the generation of the aromatic ingredients of the spirit body during different fermentation periods.
