Changes

Although the word yeast often refers to ''Saccharomyces cerevisiae'', the yeast typically employed in the production of beer, bread, and wine, '''yeasts''' are actually a broad category of unicellular fungi which reproduce by budding or fission. They may be generalists or highly specialized, and have been found to occupy an enormous range of habitats: Soil, ripe fruit, the human body, and even the upper levels of the atmosphere. Yeasts naturally exist in mixed communities with other yeasts as well as non-yeast fungi and bacteria and other fungi, although they may be manipulated by humans as monocultures. Although the most famous example is ''[[Saccharomyces]]'' there are many other genera of yeast which can produce alcohol from sugars. ''[[Brettanomyces]]'' is the most famous example of non-''Saccharomyces'' yeast which is used in beer production. In wine production, a much wider variety of yeasts have been employed (often unintentionally), and many have been found to contribute positive characteristics including esters, phenols, and glycerol.