Brettanomyces bruxellensis

Brettanomyces bruxellensis is a species of yeast in the family Pichiaceae, order Saccharomycetales, named for its association with the Senne valley near Brussels, Belgium, though it is found all over the globe and naturally inhabits the skins of fruit in the wild. It plays a key role in producing traditional Belgian beer styles such as lambic, Flanders red ales, gueuze, and kriek, and American craft brewers increasingly use it to give beer a slightly sour, earthy character; some French winemakers deliberately incorporate it as well, though in winemaking generally it is regarded as a spoilage organism producing undesirable flavors. It naturally occurs on fruit surfaces and in brewery environments, particularly in the oak barrels used to store and condition beer, and produces the enzyme vinylphenol reductase as part of its metabolism. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/