Steam beer

Steam beer is a highly effervescent beer made by brewing lager yeasts at warmer fermentation temperatures. It has two distinct but related meanings:

Historic steam beer, associated with San Francisco and the U.S. West Coast, was brewed with lager yeast without the use of true refrigeration (by ice or mechanical means). It was an improvised process, originating out of necessity, perhaps as early as the Gold Rush and at least 1860 in Nevada. It was considered a cheap and low-quality beer, as shown by references to it in literature of the 1890s and 1900s.

Modern steam beer, also known as California common beer, was originated by Anchor Brewing Company, which trademarked the term Steam Beer in 1981. Although the modern company has corporate continuity with a small brewery which has made beer since the 1890s, Anchor Steam is a modern craft-brewed lager. The company does not claim any close similarity between its present day product and turn-of-the-20th-century steam beer.