Brettanomyces

Brettanomyces is a yeast that was originally thought of as a spoilage yeast. Known for it's barnyard, fecal, horsey, metallic or Band-Aid flavors, brett was unwelcome in most breweries. But in some styles like Saison and Lambic these flavors add a layer of complexity to the beer.

Brett Strains

Guide

Brett Strain Guide provided by Funk Factory

Common Name	Species Name	Synonym (Strain) Name	Lab/Package	Flavor/Aroma	Source Note
Anomala	Dekkera anomala	B. intermedius	ECY-04	strong ester profile with some light funk and acidity	beer - Adelaide, Australia
Anomalus	Dekkera anomala	B. anomalus	Wyeast		bottled stout - Burton on Trent, England
Bruxellensis	Dekkera bruxellensis	B. bruxellensis	BSI	Same as White Labs	Pro-Brewers only.
Bruxellensis	Dekkera bruxellensis	B. bruxellensis	WLP650	Barnyard	Not the same as WY's Brux
Bruxellensis	Dekkera bruxellensis	B. bruxellensis	Wyeast 5112	"sweaty horse blanket"	Not the same as WL's Brux
Bruxellensis	Dekkera bruxellensis	B. bruxellensis	ECY-05	funky with barnyard notes accompanied by some fruit	isolated from Belgian stout
Claussenii	Dekkera anomala	B. claussenii	BSI	Same as White Labs	Pro-Brewers only.
Claussenii	Dekkera anomala	B. claussenii	WLP645	Fruity, pineapple
CMY1	Dekkera bruxellensis	B. bruxellensis CMY1	BSI		Chad Yakobson's mutation of BSI Drie
Custersianus	Dekkera custersiana	B. custersianus	ECY-19	light fruit and hay	Bantu beer brewery, South Africa
Drie	Dekkera bruxellensis	B. drei	BSI	"highly aromatic"	Isolate from Drie Fonteinen; Pro-Brewers only.
Farmhouse	?	B. fantome	ECY-03	fruity and funky profile	Isolate from Fantome
Lambicus	Dekkera bruxellensis	B. lambicus	BSI	Same as White Labs	Pro-Brewers only.
Lambicus	Dekkera bruxellensis	B. lambicus	WLP653	Horsey, Smoky, Spicy	Different from WY's "lambicus"
Lambicus	Dekkera bruxellensis	B. lambicus	Wyeast 5526	Pie-cherry	Different from WL's "lambicus"
Naardenensis	Dekkera naardenensis	B. naardenensis	ECY-30	strawberry, honey, ripe fruit with a tart, citrusy acidity after 6mo of aging	Isolated from Dr. Pepper
Nanus	Eeniella nana	B. nanus	ECY-24	spicy, saison-like profile	bottled beer - Kalmar, Sweden
Trois	Dekkera bruxellensis	B. trois	WLP644	Mango, Pineapple	Isolate from Drie Fonteinen

Smaller Labs

Name	Taxonomy	Note
BKYeast	Brett X1
BKYeast	Brett C1	Isolate from Cantillon Iris
BKYeast	Brett C2	Isolate from Cantillon Iris
BKYeast	Brett C3	Isolate from Cantillon Iris
DCYeast	DCY01
Saccharolicious	Brett I
Saccharolicious	Brett II	originates from Brasserie à Vapeur in Pipaix, Belgium, and was isolated from a bottle of Cochonne

Beer

In most beer styles Brettanomyces is viewed as a contaminant and the characteristics it imparts are considered unwelcome "off-flavours." However, in many styles, particularly certain traditional Belgian ales, it is appreciated and encouraged. Lambic and gueuze owe their unique flavour profiles to Brettanomyces, as do wild yeast saison or farmhouse styles; and it is also found in Oud Bruin and Flanders red ale.

Several American craft breweries use Brettanomyces in their beers. This use began with a renewed interest in Belgian style ales and later formed new styles altogether (Brewers Association, 2007 Great American Beer Festival Style Guidelines, section 13a, 16). Some breweries use 100% Brettanomyces for the fermentation of some of their beers, and omit Saccharomyces from the recipe. It is common for American brewers that use Brettanomyces to also include lactic acid producing bacteria such as Lactobacillus, and Pediococcus in order to provide sourness to the beer.

While Brett is sometimes pitched into the fermenter, aging in wood barrels previously infected with Brettanomyces is another method used to impart the complexity and sourness contributed by these strains of yeast.