The alcohol in beer has a certain influence on the foam and taste of beer. The alcohol content is high, the beer viscosity and foam viscosity are also high. The beer foam without alcohol is extremely unstable; the wort foam with hops does not hang in the cup, but After adding alcohol, the glass hangs obviously; the non-alcoholic beer forms little foam, and when alcohol is added, the foaming performance and foam stability are significantly improved. The effect of alcohol on foam is only within a certain range (1~3%). Exceeding this range is also detrimental to foam. In the national standard, the alcohol content of light beer is more than 3%, and the alcohol content of non-alcoholic beer is less than 0.5%. The alcohol content of the beer is also detrimental to foam, because the alcohol surface tension and other reasons have a defoaming effect.
In addition, alcohol also affects the dissolution of CO2, the main substance that forms beer foam, in beer. The lower the alcohol content, the higher the CO2 solubility; the higher the alcohol content, the lower the CO2 solubility; the solubility of CO2 in alcohol aqueous solution is lower than that in water, so alcohol is also an important factor for the solubility of CO2 in beer. influencing factors.
If the alcohol content is too high, although it will be detrimental to the solubility of beer CO2 and the foam, if the alcohol content in the beer is too small, the beer will be tasteless and tasteless, such as some low-alcohol and non-alcohol beers. This is due to the low alcohol content. Generally, beer with a high degree of fermentation has an alcohol content of more than 4%, and its “mellowness” is better. Therefore, the alcohol content is not only an important component of beer, but also an indispensable important substance for beer flavor and taste integrity. At the same time, it is a necessary component for the synthesis of some ester aroma substances in beer, such as ethyl caproate, ethyl acetate, etc. Although the content of these substances is small, they have a great impact on the flavor of beer. A moderate amount of ester flavor characteristics can add some body flavor to beer.
The general alcohol content of beer is 3-4%. This concentration has the effect of inhibiting the growth of miscellaneous bacteria. The higher the concentration, the stronger the effect, so that most miscellaneous bacteria cannot survive in beer. Therefore, alcohol can make the beer itself have a certain antibacterial and antiseptic ability, so that the beer has a certain biological stability.
The fermentation process of beer is mainly alcoholic fermentation. To ensure the production of alcohol, it is necessary to ensure reasonable process conditions. The alcohol content in beer is mainly determined by the amount of reducing sugar in the original wort and the degree of fermentation, while a certain original wort concentration and fermentation status are also determined by the fermentable sugar and low molecular nitrogen content in the wort. Rationality of components and properties of yeast.
The alcohol content of beer is one of the main indicators of beer testing items. The measurement method is to use the density bottle method specified in GB4928 to measure the density of beer distillate at 20 ℃, and obtain the alcohol content by looking up the table.
Post time: Jul-04-2022