What is a Ale, Lager, Porter, or Stout ?

Ale

Ale is a style of beer made using Saccharomyces Cerevisiae yeast. It is top fermenting beer (it flocculates, or gathers, at the top of the tank) and ferments at warmer temperatures (55-70°). Ales usually take about 2 weeks to finish. Ale yeasts will always form a “yeast bed” or sediment on the bottom.

Lager

Lager is a style of beer made using Saccharomyces Carlsbergensis (aka Saccharomyces Pastorianus). It is bottom fermenting beer (it flocculates, or gathers, at the bottom of the tank) and ferments at colder temperatures ( 40-50°, near freezing). Lagers are stored, or lagered, for longer than ales. They may take 6 weeks to finish.

Keep in mind that, due to more recent evaluation of this yeast strain, Saccharomyces Carlsbergensis has been re-classified to be included in the Saccharomyces Cerevisiae designation due to its reproductive process. Brewers still refer to the two as separate, however.

Porters & Stouts

Porter is usually produced as an ale, but may be fermented at colder temperatures using lager yeast. It’ss a dark-coloured style of beer. The history and development of stout and porter are intertwined. The name was first used in the 18th century from its popularity with the street and river porters of London. It is generally brewed with dark malts. The name “stout” for a dark beer came about because a strong porter may be called “Extra Porter” or “Double Porter” or “Stout Porter”. The term “Stout Porter” would later be shortened to just “Stout”.

Stout is a dark beer made using roasted malt or barley, hops, water, and yeast. Stouts were traditionally the generic term for the strongest or stoutest beers, typically 7% or 8%, produced by a brewery. There are a number of variations including Baltic porter, dry stout, and imperial stout. The name porter was first used in 1721 to describe a dark beer popular with street and river porters of London that had been made with roasted malts. This same beer later also became known as stout, though the word stout had been used as early as 1677.

Others

There are also beers made using Brettanomyces, Pediococcus, and Lactobacillus, or a combination of each, along with ale yeast, champagne yeast, or lager yeast. These are generally Belgian or Belgian-style beers with flavors that cross into those of wine, but with a beer presence. They are often fermented in a “cool ship,” an open vat that looks like a 2-3 foot high swimming pool. These cool ships are found on the upper floor of the breweries in Belgium, with slats that are open to the air and cobwebs hanging in the rafters above. The terroir of the region has naturally occurring zoological organisms in the air, and make this most wonderful style of beer. Americans can make this beer as well, but do not have the advantage of the rich terroir of the Zenne Valley, so this style differs from that made in Europe. Lambics, Gueuze, Biere de Garde, Biere Brut, Saison, Flemish Red, and Oud Bruin are some examples of these styles.