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Mixed-Fermentation Sour Beer

wild-fermented
Visual reference: Cantillon Grand Cru Bruocsella 2007. Not a confirmed example of Mixed-Fermentation Sour Beer. Photo: Bernt Rostad from Oslo, Norway / Wikimedia Commons · CC BY 2.0. Resized and cropped for display.

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

Color

OG, FG, IBUs, SRM and ABV are not defined independently for this category – they vary with the declared base style. BJCP 2021.

Bitterness

OG, FG, IBUs, SRM and ABV are not defined independently for this category – they vary with the declared base style. BJCP 2021.

Alcohol

OG, FG, IBUs, SRM and ABV are not defined independently for this category – they vary with the declared base style. BJCP 2021.

Sweetness

Balance

History

Classic characteristics

Flavor Profile Deep Dive

Service notes

BJCP designation

Overall Impression: A sour and funky version of a base style of beer.

Entry Instructions: Entrant must specify the beer description, identifying the microbes used and either a base style or ingredient and specification details.

Style Comparison: A sour and funky version of a base style, not necessarily as extreme as traditional European sour examples. The base beer style becomes less relevant because the yeast and bacteria tend to dominate the profile.

Vital Statistics: OG, FG, IBUs, SRM and ABV are not defined independently for this category – they vary with the declared base style. BJCP 2021.

Source: BJCP 2021 Style Guidelines, bjcp.org, retrieved 2026-09-13. Vital statistics are as published; descriptive text is condensed from the published guideline.

Brewers Association designation

Style comparison

Similar Styles

A sour and funky version of a base style, not necessarily as extreme as traditional European sour examples. The base beer style becomes less relevant because the yeast and bacteria tend to dominate the profile.

Ingredients

Brewing process

Food pairings

Spirit pairings

The soundtrack

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