An unfiltered, naturally cloudy German lager — “cellar beer” — built on a traditional base style rather than a fixed recipe. The defining trait is what is left in rather than what is dialed in: yeast in suspension, soft natural carbonation, and a fresh, lightly rustic character. Color, strength, malt, and hop levels all vary with the underlying style, which may be a Helles, Dunkel, Märzen, Vienna, Dortmunder, or other European-origin lager (or, less commonly, an ale). Franconian in origin, often served young and gently carbonated.
In the glass
Origin
Kellerbier — literally “cellar beer” — comes from Franconia in northern Bavaria and dates to the era before mechanical refrigeration, when brewers lagered their beer through the warm months in cool underground cellars and rock caves. Drawn straight from the lagering vessel, the beer was naturally cloudy with yeast and only lightly carbonated, since it had not been fully conditioned or filtered. The companion term Zwickelbier takes its name from the Zwickelhahn, the small sampling tap brewers used to draw beer from a cask or tank during lagering; the two names are now largely interchangeable. The style survived as a regional Franconian tradition and has spread with the modern interest in unfiltered, fresh-from-the-cellar lager.
Notes
Kellerbier is best understood as a way of serving and finishing a lager rather than a single recipe — the same brewery’s Helles, Dunkel, or Märzen can each appear in a keller version. The cloudiness, the soft carbonation, and a touch of yeast-derived sulfur are features, not faults: they signal a young, unfiltered beer. Franconian classics like Mahr’s Ungespundet and St. Georgenbräu set the template, the former running darker and full-bodied. The “ungespundet” label often seen on these beers refers to lagering without a full bung, which keeps carbonation low.
Defining examples
Mahr’s Bräu Ungespundet·St. Georgenbräu Keller Bier·Tucher Kellerbier·Greif Bräu Kellerbier