B64 Napoleon
Liquid Ale yeast from Imperial Yeast.
Lab
Imperial Yeast· Ale · Liquid · B64
Imperial Yeast· Ale · Liquid · B64Specs
Attenuation
77–83%
The share of sugars the yeast ferments out. Higher attenuation means a drier, stronger beer.
Optimal temp
18–26°C
64–79°F
The range where this strain ferments cleanly, without throwing off-flavors. Most brewers pitch near the low end.
Flocculation
Low
How readily the yeast clumps together and drops clear once fermentation winds down.
Alcohol tolerance
≈12% ABV
The rough ABV ceiling where the yeast stresses out and stops fermenting.
Genetic traits
Phenolics
POF+
Clove & spice
Throws phenolics — the clove and spice notes (4-vinyl-guaiacol) behind hefeweizens, witbiers, and saisons. Expect a spicy character, not a clean one.
Diastatic
STA-1+
Finishes bone-dry
Carries the STA1 (diastaticus) gene, so it keeps eating sugars other yeast leave behind and finishes very dry. It's also a contamination risk: it can over-carbonate or gush if it crosses into other beers.
Same strain, other labs
Potential substitutes for B64 Napoleon
Usually used in
Saison
Common questions
- What is the B64 Napoleon equivalent?
- LalBrew Belle Saison, M29 French Saison Yeast, OYL-026 French Saison, WLP545 Belgian Strong Ale Yeast, and 3711 French Saison — the same strain from other labs, the Belle Saison / French Saison (3711) strain.
- What is B64 Napoleon's attenuation?
- 77–83% apparent attenuation.
- What temperature should I ferment B64 Napoleon at?
- 18–26°C is the recommended range.
- Does B64 Napoleon produce phenolics (clove and spice)?
- Yes. B64 Napoleon is POF-positive — it makes 4-vinyl-guaiacol, the clove and spice character of hefeweizens, witbiers, and saisons.
- Is B64 Napoleon diastatic (STA-1)?
- Yes. B64 Napoleon carries the STA1 gene (S. cerevisiae var. diastaticus). It super-attenuates to a dry finish, and can over-carbonate or gush if it cross-contaminates other beers.
- What beer styles is B64 Napoleon good for?
- Saison.
- What can I substitute for B64 Napoleon?
- SafAle BE-134, SafAle BE-256, WLP590 French Saison Ale Yeast, and M41 Belgian Ale Yeast.
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