Malt aroma & flavor
Sweet malt character is not present. Some versions may exhibit attributes typical of specialty malts.
Belgian and French Origin Ale Styles
Contemporary Belgian-Style Spontaneous Fermented Ale
Ale · Gold to very dark
What to expect
Malt character: Sweet malt character is not present. Hop character: Not present to low and can include floral or other attributes typical of aged or unaged hops.
Reading guide · The complete guideline attributes below preserve the source’s qualifications.Color · SRM
6–40
Pale / strawBlack
Gold to very dark · Illustrative colors on the shared, uneven SRM scale.
Explore styles overlapping this color rangeAlcohol · ABV
5.0–8.9%
Reference scale, not a limit on official guideline values.
Bitterness · IBU
11–23
Measured bitterness; perceived bitterness is described in the guideline below.
Brewers Association 2026 · Printed guideline page 28 · PDF page 37. Color graphics are illustrative.
The guideline, in detail
Official style attributes, including what may be present and what should be absent.
Hop aroma & flavor
Not present to low and can include floral or other attributes typical of aged or unaged hops.
Perceived bitterness
Very low
Body & mouthfeel
Very low with dry mouthfeel
Clarity
Cloudiness is acceptable, as these beers are frequently bottle conditioned.
Color
Gold to very dark
Fermentation characteristics
These blended and secondary fermented beers may be very dry or mildly sweet. They are characterized by intense fruity ester, sour, and acidic attributes which only result from spontaneous fermentation. Diacetyl should not be present. Characteristic horsey, goaty, leathery, and phenolic aromas and flavors derived from Brettanomyces yeast are often present at moderate levels. Aged beer is often blended with young beer to create this special style. Vanillin and other wood-derived flavors may range from absent to present at up to low-medium levels. Carbonation can be none (flat) to high.
Additional guideline notes & competition context
Contemporary Belgian-Style Spontaneous Fermented Ales takes its inspiration from the Traditional Gueuze whose origin is the Brussels area of Belgium. But these beers incorporate specialty malts, spice(s), fruit(s), or many other diverse ingredients and processes that influence the hue, aroma and flavor outcomes of the finished beers such that they differ significantly from traditional examples. When using these guidelines as the basis for evaluating entries at competitions, brewers may be asked to provide supplemental information about entries in this category to allow for accurate evaluation of diverse entries. Such information might include the underlying beer style upon which the entry is based, or other information unique to the entry such as non-traditional malts, sweeteners, fruit(s), spice(s) or any other ingredients or processing which influence perceived sensory outcomes.
Technical specifications, including gravity
Original Gravity (°Plato) 1.044-1.072 (11-17.5 °Plato) • Apparent Extract/Final Gravity (°Plato) 1.004- 1.016 (1-4.1 °Plato) • Alcohol by Weight (Volume) 4.0%-7.0% (5.0%-8.9%) • Hop Bitterness (IBU) 11-23 • Color SRM (EBC) 6-40 (12-80 EBC)