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Steam beer (California common) - a hybrid from the gold rush era

Most beers divide into lagers and ales, depending on the yeast and the fermentation temperature. But there is a style that breaks this rule: steam beer, also known as California common. It is an American hybrid born of necessity in the gold rush era, when ice was scarce and beer somehow had to be brewed in the warm climate of California. The solution turned out to be fermenting lager yeast at the warmer temperature typical of an ale - and so a style was born that combines features of both worlds. It is a piece of American brewing history, revived in the days of the craft revolution. Here is a guide to steam beer: where it came from, why it is called California common, what role the Anchor brewery played and what this beer hybrid really means.

A hybrid between lager and ale

Steam beer is a style that does not fit the simple division into lagers and ales. It is made with lager yeast (bottom-fermenting), but fermented at the warmer temperature typical of an ale. The result is a very characteristic profile combining features of both kinds: the cleanness and fullness of a lager with the fruity notes and character of an ale. It produces a beer that is amber, medium-strong, with a slightly fruity, bready and minty-spicy note, and a clear bitterness. It is literally a beer from the borderland of two worlds. Understanding that steam beer is a hybrid - lager yeast at ale temperature - is the key to the whole style. It is a breach in the beer divisions. It is a style that proves the line between lager and ale can be fluid. We cover this division more in lagers and ales.

Born in the gold rush era

Steam beer was born of pure necessity. In the mid-nineteenth century, during the California gold rush, crowds thirsty for beer poured into San Francisco. Brewers wanted to brew lagers, fashionable thanks to German immigrants, but there was no ice, no cold stores, not even the cold water needed for traditional cold lager fermentation. So they improvised: they began to ferment lager yeast at the warmer ambient temperature, typical of an ale. It was a solution out of poverty, and the resulting beer was regarded as cheap and common - mentions in the literature of the turn of the twentieth century treat it with disdain. Understanding that steam beer is a child of the gold rush and the lack of ice explains its nature. It is a beer born of ingenuity. It is the taste of the Wild West in a glass.

Where the name steam comes from

Where did the name steam come from? The most popular theory concerns the way the wort was cooled. Brewers in San Francisco pumped the hot wort into shallow, open vessels on the roofs of breweries, so that the cool air off the Pacific would chill it quickly. As a result, a characteristic cloud of steam hung over the roof - hence, supposedly, the name steam beer. Other theories link it to the pressure (steam) in the casks when pouring young, still-fermenting beer. The true source of the name has not been established for certain to this day. Interestingly, the term steam beer itself has roots in Bavaria, Germany, and only in America became tied to San Francisco. Understanding that the name refers to the steam over the cooling beer adds charm to the style. It is a vivid, almost poetic name. It is a piece of beer folklore.

Anchor Steam - rescue from oblivion

Steam beer might have vanished from history were it not for one brewery: the Anchor Brewing Company of San Francisco. Although the firm’s roots reach back to the 1890s, it was the modern brewery that saved the style from oblivion and in 1981 trademarked the term Steam Beer. Thanks to this, the name Anchor Steam became a synonym for the style, and other brewers had to use the term California common. Anchor itself stressed that its modern beer was a contemporary craft product, not necessarily identical to the one from the turn of the century. Sadly the brewery ceased operations in 2023, closing an important chapter. Understanding the role of Anchor - rescuing the style and trademarking the name - explains why we now say California common. It is a brewery that saved a piece of history. It is a monument to American brewing.

A table: steam beer in brief

Let us gather the key features:

The table shows the essence of steam beer: the hybrid of yeast and temperatures, the origin in the gold rush and the role of Anchor. It is a style simple to describe, yet deep in history.

Why California common

Since Anchor trademarked the name Steam Beer, the rest of the world needed another term for the same style. So the term California common was born - the official, generic name of the style in competitions and among home brewers. It captures the origin (California) and the character (common, that is an ordinary, everyday beer of the people). It is the same style as historic steam beer, only without the trademarked trade name. Today California common is brewed by craft breweries and home brewers all over the world, prized for its simplicity and interesting history. Understanding that steam beer and California common are two names for the same style clears up the most common misunderstanding. It is a matter of law, not a difference in the beer. It is the same taste under two labels.

Taste and character

What does steam beer taste like? It is a beer from amber to copper, of medium strength, with a clear but not aggressive bitterness. Lager yeast in warm fermentation gives delicate fruity and slightly minty-spicy notes, against a bready, caramel malt. Traditionally the American hop Northern Brewer is used, lending a herbal-minty, woody accent. The result is a beer as clean and refreshing as a lager, but with a touch of the character and complexity of an ale - balanced, drinkable, versatile. It is not a showy style like a heavily hopped IPA, but a solid, classic beer with its own identity. Understanding its profile lets you appreciate this balance. It is a beer that is modest yet satisfying. It is a harmony of two beer worlds. We cover the role of yeast more in beer yeast.

Why it is worth knowing

Steam beer is more than a curiosity - it is a living piece of American beer history. It shows how constraints (lack of ice, a hot climate) can give birth to an original style. It is one of the few beer styles born in the United States itself, rather than imported from Europe. For a beer lover it is a lesson that the division into lagers and ales is not absolute, and brewers’ creativity can cross it. It is also a nod to the craft heritage of San Francisco. By reaching for a California common, you drink a piece of nineteenth-century history revived today. Understanding its significance turns every sip into a little journey through time. It is a style with a soul. It is proof that necessity can be the mother of flavour.

How to serve it and what to pair

Steam beer is a versatile and rewarding beer at the table. Serve it lightly chilled, around 8-10 degrees - too cold will mute its fruity-bready notes, too warm will exaggerate the bitterness. A slender glass or a classic mug suits it best, which will emphasise the amber colour and let the aromas develop. Thanks to its balanced build, between the cleanness of a lager and the character of an ale, California common works great with food: it pairs with grilled meat, burgers, roast poultry, aged cheeses and even moderately spicy dishes. Its bitterness cleanses the palate, and the bready-caramel malt complements the flavours of the food. It is an everyday beer, not just one for tasting. Understanding how to serve and pair it lets you draw out its fullness. It is a versatile companion at the table. It is a classic that fits almost anywhere.

The essentials in brief

Let us gather it up. Steam beer, or California common, is an American hybrid: lager yeast fermented at the warmer temperature typical of an ale. The style was born in San Francisco during the gold rush of the mid-nineteenth century, when the lack of ice forced brewers to improvise. The name steam probably refers to the cloud of steam over the wort cooled on the roofs. The Anchor brewery saved the style from oblivion and in 1981 trademarked the name Steam Beer, which is why the rest of the world says California common. It is an amber, medium-strong beer with a fruity-bready profile and a clear bitterness, combining the cleanness of a lager with the character of an ale. Now you know why it is worth knowing this piece of beer history.

Note every beer in GustoNote - including steam beer and the lager and ale features you sense in it. In time you will recognise this characteristic hybrid of two beer worlds yourself.