Lager
Lagers are brewed using yeast strains that ferment at cooler temperatures. These strains are often called "bottom-fermenting yeasts" because fermentation takes place at or near the bottom of the fermentation vessel. Cooler temperatures generally result in a longer (than ale) fermentation and aging process for lager production (lager means “to store” in German). Lager yeasts, due to the cooler temperatures, tend not to produce esters, thus imparting a cleaner, smoother character in the beer, something for which lagers are generally known.
