Brettanomyces, the Wild Yeast
For those accustomed to lambics, Flemish red ales, gueuze, or sour ales, the characteristics of Brettanomyces yeast in beer are either thought of as unwelcome and unpleasant or exciting and refreshing. Beers produced with this yeast tend to have a much crisper acidity, sometimes slightly medicinal phenolic notes, and sometimes more floral flavors. More commercially successful uses of Brettanomyces are Belgian Brewery Lindemans' lambic beers which are brewed with fruits (their framboise and kriek are particularly popular).
The asexually reproductive microorganism, "Brett" gets its name from the Greek for "British fungus" at one point in time associated with British old stock ale. It is nowadays most commonly recognized as the yeast responsible for the more floral and tart character of Belgian lambic beers. But as increasingly more American brewers have started to experiment with various ingredients, adjuncts, grains, and yeasts in beer, Brettanomyces has begun to settle into American craft beer as a very American yeast.
Often called wild or "Brett" beers, modern craft breweries have begun to adopt this strain of yeast in novel combinations. The Bruery'sTart of Darkness is an example of a barrel aged stout that is given a healthy dose of souring bacteria in addition to Brettanomyces producing a uniquely sour stout, a style that is uncommon. But the practice of barrel aging beers produced with Brettanomyces is not as uncommon as pairing the yeast with darker grains. In fact, the practice of incorporating Brettanomyces during barrel aging helps to liven barrel-aged beers by imparting a crisp acidity as the yeast consumes the small amounts of oxygen that make their way into the beer through the wood barrels.
In the wild, Brettanomyces' natural habitat is on the skins of fruit, but the strains of Brettanomyces used in modern commercial craft brewing are anything but wild. These tend to be controlled cultured strains of these microorganisms. Of the varieties of Brettanomyces that exist, only two are really used in modern brewing applications: These are Brettanomyces bruxellensis and Brettanomyces anomalus, sometimes known as Brettanomyces lambicus and Brettanomyces claussenii.
The primary byproduct of yeast in fermentation is alcohol, but Brettanomyces is unique in the amounts of acetic acid produced during the process given greater amounts of oxygen, able to oxidize ethanol and residual sugars in beer. But it is lactic acid that is most commonly responsible for the sour character in beers and is often paired with Brettanomyces to produce crisp, sour ales in the form of lactic acid producing bacteria such as Lactobacillus, also present in yogurt, cheese, and kimchi among other foods.
The asexually reproductive microorganism, "Brett" gets its name from the Greek for "British fungus" at one point in time associated with British old stock ale. It is nowadays most commonly recognized as the yeast responsible for the more floral and tart character of Belgian lambic beers. But as increasingly more American brewers have started to experiment with various ingredients, adjuncts, grains, and yeasts in beer, Brettanomyces has begun to settle into American craft beer as a very American yeast.
Often called wild or "Brett" beers, modern craft breweries have begun to adopt this strain of yeast in novel combinations. The Bruery'sTart of Darkness is an example of a barrel aged stout that is given a healthy dose of souring bacteria in addition to Brettanomyces producing a uniquely sour stout, a style that is uncommon. But the practice of barrel aging beers produced with Brettanomyces is not as uncommon as pairing the yeast with darker grains. In fact, the practice of incorporating Brettanomyces during barrel aging helps to liven barrel-aged beers by imparting a crisp acidity as the yeast consumes the small amounts of oxygen that make their way into the beer through the wood barrels.
In the wild, Brettanomyces' natural habitat is on the skins of fruit, but the strains of Brettanomyces used in modern commercial craft brewing are anything but wild. These tend to be controlled cultured strains of these microorganisms. Of the varieties of Brettanomyces that exist, only two are really used in modern brewing applications: These are Brettanomyces bruxellensis and Brettanomyces anomalus, sometimes known as Brettanomyces lambicus and Brettanomyces claussenii.
The primary byproduct of yeast in fermentation is alcohol, but Brettanomyces is unique in the amounts of acetic acid produced during the process given greater amounts of oxygen, able to oxidize ethanol and residual sugars in beer. But it is lactic acid that is most commonly responsible for the sour character in beers and is often paired with Brettanomyces to produce crisp, sour ales in the form of lactic acid producing bacteria such as Lactobacillus, also present in yogurt, cheese, and kimchi among other foods.
Source...