Kellerbier literally translates to “celler beer” in German. It brings us back to Franconia, Bavaria in the latter half of the Middle Ages.
This was a time when brewers would lager their beers in caves because the refrigeration we take for granted these days was not invented yet.
German brewers would brew their beers during the cool months and then age them in the caves. These caves were naturally cool areas that would maintain stable temperatures, perfect for a slow maturation process for their beers.
Typically Kellerbiers are unpasteurized. To understand unpasteurized beers, it’s best to think about pasteurized beer.
Many commercial breweries will run their bottles and cans through hot water spray that will kill any bacteria and stop any yeast growth. An unpasteurized beer will skip this process.
As a result of this, the beer should be continuously chilled and consumed close to the production date.
Amber Kellerbiers (and Pale Kellerbiers as we will see next week) are traditionally conditioned in an oak cask that is open to the environment it is held in with an unplugged bug hols.
This will allow CO2 from secondary fermentation to escape and allow in anything from the surrounding environment. This would lead to differences in each Kellerbier.
The result of holding these beers in these casks results in a beer that is minimally carbonated and very cloudy with yeast and nutrients settling out in the beer. Usually the yeast and nutrients would be filtered out of the beer.
Kellerbier has survived the test of time largely in part of the Franconian love that exists in this region of Germany. It is remarkable that a small area in a country can be responsible for a beer’s history and have it continue over time.