WLP645 Claussenii - Brett¶

WB-BUG-2026-001 · stage: banked · started 2026-05-01 (month known, exact day not recorded)

General Notes¶

Pitched from a White Labs WLP645 PurePitch pouch, bought for its advertised tropical, pineapple-like character. Primary fermentation at 29-30°C was very sluggish and finished comparatively under-attenuated: the beer came out rather flat and uninteresting, low in acidity, no discernible tropical aromas and high THP (mousy/cereal-family tetrahydropyridine) character. Two slants and one slurry tube are now banked; no colonies picked or isolate testing planned.

WLP645 Brettanomyces claussenii, White Labs, PurePitch Next Generation pouch. Batch or best-before not recorded. Bought as a pure commercial culture, specifically for its listed tropical aroma potential; background on the strain is in Technical notes below.

Technical notes¶

White Labs' own description: a low-intensity Brett strain closely related to B. anomalus, with a "fruity, pineapple-like aroma with an earthy, hay-like background", low flocculation, 8–12% alcohol tolerance, and a suggested fermentation temperature around 30°C. Originally isolated from strong English stock beer in the early 20^th century.¹

Tetrahydropyridines (THP) are produced by some Brettanomyces strains; production is stimulated by oxygen exposure, and the flavour is much harder to detect at low pH.³ Worth noting given the THP character reported here and the low acidity of this batch (a higher pH generally makes THP easier to detect).

Morphology¶

Microscopy¶