Top-fermenting yeast
Top-fermenting yeast, saccharomyces cerevisiae, is one of the two types of yeast used in the brewing of beer, so called because when the fermentation process is complete it rises to top of the fermentation vessel. Beers that use only top-fermenting yeast are called ales, and for that reason these yeasts are also sometimes called "ale yeasts".
Top-fermenting yeasts are unable to ferment some types of sugars, and the resulting beer is sweeter and "fruitier".
See also
Categories: Beer and brewery stubs | Beer