In beer production, there are three common sterilization methods :(1) rapid flow Pasteur sterilization; (2) tunnel Pasteur sterilization; (3) aseptic filtration.
Each of these three methods has advantages and disadvantages.
Pasteurization, of any kind, kills living yeasts and bacteria in beer by heating it. When handled according to the specifications, the beer is biologically stable, allowing it to be stored at room temperature for months without going bad. The same effect can be achieved by using aseptic filtration, the basic principle of which is to pass the beer through a filter and remove the microorganisms from the beer.
In Pasteur tunnel pasteurization, bottles or cans with beer are sent through conveyors into a tunnel, where hot water is sprayed to keep the temperature of the beer above 60℃ for a period of time and then cold water will spray to cool the beer.
When rapid flow Pasteurization is used, the beer passes through two heat exchangers. The first one heats the beer to more than 70℃ and stays there for a few seconds. The second heat exchanger will cool the beer.
All three methods affect the flavor of the beer, but the degree of damage is not the same.
Aseptic filtration will reduce the mellow feeling and color of beer. The filter will remove the macromolecules from the beer, and these macromolecules, such as protein and dextrin, are part of the flavor and color of the beer. So, aseptic filtration is more suitable for the production of clear beers.
Pasteur sterilization accelerates the oxidation of beer after a period of heating, which reduces the flavor. The degree of damage is directly related to the heating temperature, time and beer itself. Obviously, the less air at the top of the bottle, the less pasteurization will have an effect if the hot wort is properly treated.
In contrast, the effect of rapid pasteurization on beer is less, although the heating temperature is high, but the duration is very short, and before sterilization, beer has been heated, contains less oxygen, and rapid pasteurization requires the use of aseptic filling, biological stability is better.
Finally decided to adopt what kind of sterilization method, we need to accord the actual situation to determine and need to assess the effect of sterilization methods for wine, at the same time, also need to consider the investment, aseptic filtration membrane costs money, aseptic filling equipment is more expensive and the tunnel pasteurization is relatively cheaper.
