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lager
Ale and Lager...what are they?
Beer is the overall generic term for fermented malt beverages – whether it is an ale or a lager, it is still called beer! There are ONLY two kinds of beer – ales and lagers. Within those two broad categories there are many styles. Major ales styles are pale ale, IPA, porter, stout, and barleywine, just to name a few. Among the major lager styles are pilsner, Märzen, bock, and dunkles (dark lager).
What really differentiates an ale from a lager is the temperature of fermentation. Ales ferment typically between 64 and 70 degrees F, and lagers ferment typically between 52 and 58 F. Fermentation is the process whereby yeast consumes the sugars from the malt, and in turn produces alcohol and carbon dioxide. All yeast strains, in addition to producing alcohol and CO2, also produce small amounts of other compounds which add subtle flavor complexity to the beer.
With warmer fermentation temperatures (ales), yeast will produce elevated ester compounds. These come across on the palette as a rounded fruitiness, and give ales their characteristic complexity. Typically, ale yeasts will not ferment at colder (lager) temperatures.
Colder fermentations obviously require a yeast that is genetically capable of fermenting at colder temperatures (as opposed to ale yeasts). The colder temperatures prevent these lager yeasts from producing the amount of esters which are so characteristic of ales. However, many popular lager yeasts do produce elevated sulfur compounds during fermentation. These sulfur compounds take extended cold storage (known as lagering) to be pleasantly integrated into the beer, but once accomplished, these compounds show on the palette as “crispness” and “cleanness”.
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