A glass of Viking lager
A glass of Viking lager

Lager is a type of beer which was first brewed in Central Europe some 500 years ago, and has since become the most popular type of beer in the world. The word comes from German and means "storage". Traditionally, the beer is stored for several weeks or longer before being served. Lager is a general term that includes several variations or styles, such as Pilsener, Vienna and Märzen.

Lager is distinguished from ale by its yeast. Lager yeast ferments at colder temperatures and flocculates on the bottom of the fermenting vessel, while ale yeast ferments at warmer temperatures and settles on the tops of fermentation tanks.[citation needed] The organism most often associated with lager brewing is Saccharomyces pastorianus, a close relative of Saccharomyces cerevisiae.

As the modern definition of lager relates only to the method of fermentation, lager beers' characteristics are quite varied.

The default lager encountered in worldwide production is light in color and usually represents the helles, pale lager or Pilsener styles. The flavor of these lighter lagers is usually mild and the producers often recommend that the beers be served refrigerated. However, the examples of lager beers produced worldwide vary greatly in flavor, color, and composition.

In color, while helles and pale lager represent the lightest lagers at as pale a color as 6 EBC, the darkest are Baltic porters which can be as dark as 400 EBC; darker German lagers are often referred to as Dunkel lagers.

The flavor of a lager can be quite simple, with the most mild being light lagers. The most complexly-flavored lagers are usually the darkest, although few lagers feature strong hop flavoring compared to an ale of similar alcohol by volume. In general, however, lagers display less fruitiness and spiciness than ales, simply because the lower fermentation temperatures associated with lager brewing cause the yeast to produce fewer of the esters and phenols associated with those flavors.

In strength, lagers represent some of the world's most alcoholic beers. The very strongest lagers often fall into the German-originated doppelbock style, with the strongest of these commercially produced, Samichlaus, reaching 14% ABV. (Full article...)