The influence of cellar bottom environment on the quality of sauce-flavored base liquor Moutai Wang Chao The production of liquor in China is mainly based on starch as the brewing raw material, and the koji is the saccharification starter agent, which adopts solid, semi-solid or liquid fermentation methods, and is distilled, stored, blended and other processes after fermentation. The flavor types of liquor in China can be divided into: strong flavor type, sauce flavor type, light fragrance type, rice flavor type and other flavor types, and other flavor types include phoenix flavor type, sesame flavor type, soy flavor type and concurrent flavor type.
In this paper, the results were drawn by simulating the possible conditions of the fermentation pond of sauce-flavored liquor, simulating water seepage in the cellar, simulating air leakage in the cellar, and simulating the blockage of the bottom ditch in the cellar tank, and the yeast, anaerobic bacteria, moisture, acidity value, and reducing sugar content in different rounds of fermented grains were measured, and the base liquor distilled from different rounds of fermented grains was evaluated.
In the case of air leakage at the bottom of the cellar, the anaerobic bacteria and yeast in each round of fermented grain are greatly affected, the anaerobic bacteria at the bottom of the cellar are inhibited, the yeast multiplies in large quantities due to sufficient oxygen, and the small number of anaerobic bacteria may be caused by two aspects, the yeast multiplies in large quantities and has an inhibitory effect on anaerobic bacteria; Because of the air leakage at the bottom of the cellar, there is sufficient oxygen, which has an inhibitory effect on anaerobic bacteria.
The acidity value in the fermented grain was closely related to the reducing sugar, and there was a significant downward trend in the acidity of the fermented grain, while the reducing sugar reached the maximum, which may be due to the reduction of acidic substances due to microbial metabolism, thereby promoting the utilization and hydrolysis of starch and increasing the reducing sugar content. In the third round of wine, the body of the wine has changed, the body is colorless and transparent, the sauce aroma (taste) is obvious, there is a faint ethyl acetate aroma, the body is mellow and clean.
In the case of water seepage at the bottom of the cellar, in the lower sand stage, the number of yeast in the upper layer is relatively large and the number of anaerobic bacteria in the lower layer is relatively small, and the infiltrated water may contain oxygen, so that the anaerobic bacteria in the lower layer are inhibited, and the yeast multiplies in large quantities. The water content of the fermented grain at the bottom of the cellar changed obviously, showing a trend of first rising and then decreasing, the fermented grain at the bottom of the cellar absorbed the infiltrated water until the fermented grain absorbed water to saturation, and then because of the action of microorganisms on the fermented grain, the water storage capacity of the fermented grain decreased, and the water in the fermented grain showed a downward trend.
The acidity value and reducing sugar content in the fermented grain at the bottom of the cellar were affected to varying degrees, and the flavor of the sauce in the 3rd round was transformed into a mellow sweet body, and the flavor grade of the sauce in the 4th round was reduced, which may be related to the anaerobic bacteria in the fermented grain, and the anaerobic microorganisms multiply and metabolize in large quantities, producing a large number of acidic substances such as caproic acid and lactic acid, which enter the fermented grain, resulting in the deviation of the distilled liquor.
When the ditch at the bottom of the cellar was blocked, the anaerobic bacteria in the fermented grain were higher than those in the other experimental groups, and after the second round of wine, the number of anaerobic bacteria and yeast cells in the lower layer was smaller than that in the middle and upper layers, which may be due to the metabolites produced by fermentation at the bottom of the cellar, which played an inhibitory role in microorganisms. The blockage of the cellar ditch has a certain effect on the moisture of the fermented grain at the bottom of the cellar, and it has been on an upward trend from Xiasha to 5 rounds of wine, and only slowly decreases after 5 rounds of wine.
The water produced by microbial metabolism enters the cellar bottom and is absorbed by the fermented grain until it is saturated, and the water storage capacity of the fermented grain slowly decreases under the action of microorganisms, and after 5 rounds of wine, it shows a downward trend. The acidity value in the fermented grain was closely related to the reducing sugar, and there was an obvious downward trend in the acidity of the three fermented grains, while the reducing sugar reached the maximum, which may be due to the reduction of acidic substances due to microbial metabolism, thereby promoting the utilization and hydrolysis of starch and increasing the reducing sugar content.
After that, the fermented grain maintains a high acidity, inhibits the hydrolysis of starch, and reduces the reducing sugar content in the first round of liquor, and the grade of the liquor body is reduced, which may be due to the blockage of the cellar bottom ditch, which makes the fermented grain at the bottom of the cellar have a large water content, poor air permeability, and lack of necessary dissolved oxygen, resulting in the proliferation and metabolism of anaerobic microorganisms, producing a large number of acidic substances such as caproic acid and lactic acid.
At present, the high-temperature accumulation process of sauce-flavored liquor is introduced and applied in the production of high-quality liquor or flavored liquor to improve the quality of liquor. However, due to the traditional attributes of Chinese baijiu, there is a lack of in-depth research on the influence of the cellar environment on the soy sauce baijiu, and the workers and masters in the workshop of the distillery need to rely on the experience of the master to complete the situation that occurs in the fermentation process, and there is a lack of data-based judgment basis.