American sour ales range from golden to deep copper to brown in color. Wood- and barrel- aged sour ales are classified elsewhere. Acidity from lactic, acetic and other organic acids are naturally developed with acidified malt, in the mash or in fermentation by the use of various microorganisms including certain bacteria and yeasts. Acidic character can be balanced by several types of acid and characteristics of age.. The evolution of natural acidity develops balanced complexity. Horsey, goaty, leathery and phenolic character evolved from Brettanomyces organisms and acidity may be present but should be balanced with other flavors Residual flavors that come from liquids previously aged in a barrel such as bourbon or sherry should not be present. Wood vessels may be used during the fermentation and aging process, but wood wood-derived flavors such as vanillin should not be present. In darker versions, roasted malt, caramel like and chocolate like characters should be subtle in both flavor and aroma. American sour ales may have an evident hop aroma, medium hop bitterness, low to medium hop flavor and low to medium body. Estery and fruity-ester characters are evident, sometimes moderate and sometimes intense, yet balanced. Diacetyl and sweet corn-like dimethylsulfide (DMS) should not be perceived. Chill haze is allowable at cold temperatures. Balanced fruit flavors will be evident in fruit flavored American-Style Sour Ales and be in balance with other characters.
Origin: North American
Recommended Glassware: Flute Glass or Cervoise Glass
Original Gravity (ºPlato): 1.040-1.060 (10-15 ºPlato)
Apparent Extract/Final Gravity (ºPlato): 1.010-1.018 (2.5-4.5 ºPlato)
Alcohol by Weight (Volume): 3.3-5.0% (4-6.4%)
Bitterness (IBU): 20-40
Color SRM (EBC): 6-26 (12-52 EBC)
Sub-style guidelines used with permission of the Brewers Association, www.beertown.org.