After grain (usually barley) has been processed to malt it has to be broken in milling. The actual brewing process starts with the mashing. Water is heated to about 45 - 60 ° C and added to the crushed malt. The resulting mash is heated with constant stirring depending on the process to about 75 - 78° C. In various snap-set temperatures enzymes converts the starch from the malt into fermentable malt sugar. Alternatively, parts of the mash are boiled, resulting in a physical gelatinization of the starch for a better starch degradation. With an iodine sample is then determined whether the dissolved starch is completely saccharified. This is typical for KLD and KLW.
Then the mash is transfered in the Lauter tun for lautering. The spent grain is separated from the wort (the name of the liquid, fermentable part of the mash). By second wort with hot water, the wort is purged from the spent grain and then cooked in the boiling kettle with hops.
The following procedure is called casting out. Here, the Sud is pumped out from the wort kettle into a whirlpool or through a filter to separate the coagulated proteins and other suspended solids from the wort.
Finally, the liquid wort is cooled in a cooler (cooling) on the optimal fermentation temperature and added to a suitable yeast culture, depending on the type of beer. Top fermenting yeasts ferment at temperatures between 20 ° C and 24 ° C, bottom-fermented at 10 ° C to 12 ° C. When the alcoholic fermentation the yeast converts the dissolved sugars to ethanol and carbon dioxide. This gas remains bound partly in the finished beer under pressure as carbonic acid.
After the primary fermentation, which takes about a week, the green beer must still secondary fermentation (or maturation) and store about four to six weeks.
The matured beer is filtered normally again and finally filled in bottles, barrels or cans.