WLP4021 Saison Ale Yeast Blend II
Liquid Ale yeast from White Labs.
Lab
White Labs· Ale · Liquid · WLP4021
White Labs· Ale · Liquid · WLP4021Specs
Attenuation
85–100%
The share of sugars the yeast ferments out. Higher attenuation means a drier, stronger beer.
Optimal temp
20–27°C
68–81°F
The range where this strain ferments cleanly, without throwing off-flavors. Most brewers pitch near the low end.
Flocculation
Medium
How readily the yeast clumps together and drops clear once fermentation winds down.
Alcohol tolerance
≈15% 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.
Common questions
- What is WLP4021 Saison Ale Yeast Blend II's attenuation?
- 85–100% apparent attenuation.
- What temperature should I ferment WLP4021 Saison Ale Yeast Blend II at?
- 20–27°C is the recommended range.
- Does WLP4021 Saison Ale Yeast Blend II produce phenolics (clove and spice)?
- Yes. WLP4021 Saison Ale Yeast Blend II is POF-positive — it makes 4-vinyl-guaiacol, the clove and spice character of hefeweizens, witbiers, and saisons.
- Is WLP4021 Saison Ale Yeast Blend II diastatic (STA-1)?
- Yes. WLP4021 Saison Ale Yeast Blend II 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.
Brew with WLP4021 Saison Ale Yeast Blend II
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