Fermentation can take up to several weeks depending on the style of beer to be produced. The beer is chilled to near freezing and held there for several days to several weeks depending on the desired beer. Many chemical processes take place during this time which make a clean, good tasting, homogeneous beer. Extended conditioning time naturally clarifies the beer. The clarified beer is recovered into the brite beer tank from where it is pumped to a packaging line.
Sterile filtration is one way to ensure microbiological stability.
This process strips the beer to remove bacteria which may have inadvertently been introduced during the process. Filtration to below one micron also strips some flavor and mouth feel components of the beer. Pasteurization is another way of making the product microbiological stable and thus can increase shelf life. It is the heating of the product to kill any bacteria which it may contain. A tunnel pasteurizer is employed after the product has been filled into containers.