28B. Mixed-Fermentation Sour Beer

Intended for beer fermented with any combination of Sacch, Lacto, Pedio, and Brett (or additional yeast or bacteria), with or without oak aging (except if the beer fits instead in 28A or 28D).

Overall Impression

A sour and funky version of a base style of beer.


Variable by base style. Clarity can be variable; some haze is not a fault. Head retention can be poor.


Variable by base style. The contribution of non-Sacch microbes should be noticeable to strong, and often contribute a sour and funky, wild note. The best examples will display a range of aromatics, rather than a single dominant character. The aroma should be inviting, not harsh or unpleasant.


Variable by base style. Look for an agreeable balance between the base beer and the fermentation character. A range of results is possible from fairly high acidity and funk to a subtle, pleasant, harmonious beer. The best examples are pleasurable to drink with the esters and phenols complementing the malt or hops. The wild character can be prominent, but does not need to be dominating in a style with an otherwise strong malt or hop profile. Acidity should be firm yet enjoyable, and ranging from clean to complex, but should not be biting or vinegary; prominent, objectionable, or offensive acetic acid is a fault. Bitterness tends to be low, especially as sourness increases.


Variable by base style. Generally has a light body, almost always lighter than what might be expected from the base style. Generally moderate to high carbonation, although often lower in higher alcohol examples.


The base beer style becomes less relevant in this style because the various yeast and bacteria tend to dominate the profile. Bitterness is often reserved since bitter and sour flavors clash on the palate. Inappropriate characteristics include diacetyl, solvent, ropy or viscous texture, and heavy oxidation.


Modern American craft beer interpretations of Belgian sour ales, or experimentations inspired by Belgian sour ales.

Characteristic Ingredients

Virtually any style of beer. Usually fermented by some combination of Lacto, Pedio, Sacch, and Brett. Can also be a blend of styles. Wood or barrel aging is very common, but not required; if present, should not be a primary or dominant flavor.

Style Comparison

A sour and funky version of a base style, but do not necessarily have to be as sour or as funky as some traditional European sour examples.

Entry Instructions

The entrant must specify a description of the beer, identifying yeast or bacteria used and either a Base Style, or the ingredients, specs, or target character of the beer.

Vital Statistics

Variable by style

Commercial Examples

Boulevard Love Child, Jester King Le Petit Prince, Jolly Pumpkin Oro de Calabaza, Lost Abbey Ghosts in the Forest, New Belgium Le Terroir, Russian River Temptation.