In the traditional way of beer production, the saturation of the beer is usually returned by the carbon dioxide produced during the fermentation process. However, in modern fermentation processes, carbonation can be done with some equipment, which greatly reduces the total production time.
The carbon dioxide that slowly dissolves in the beer at low temperatures tends to bind to certain components of the beer, giving it a high stability, which facilitates foam retention and prevents bacterial contamination. And the precipitated part of the hop resin gives a softer bitterness.
Generally speaking, the finished beer should contain about 0.5% carbon dioxide.
The amount of carbon dioxide dissolved in the beer is related to the pressure of the tank and the temperature at which the beer is stored. The higher the tank and the lower the temperature, the more carbon dioxide will be dissolved in the beer. At constant pressure, for every degree of temperature increase, the CO2 in the beer decreases by 0.01%; at isothermal conditions, for every 0.01Mpa increase in pressure, the CO2 increases by 0.03-0.04%.
In general, the CO2 content of beer at the bottom of the storage tank is higher than that of beer at the top. 1 meter of beer height will generate a pressure of about 0.01Mpa, and the CO2 content will increase by 0.03-0.04%.