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In ''Saccharomyces'' species, higher fermentation temperature has been associated with faster fermentation, higher growth rates, and ester formation. [https://onlinelibrary.wiley.com/doi/full/10.1002/jib.565 Tyrawa et al. (2019)] set out to explore the impact of fermentation temperature on 7 beer strains (including BSI Drei and several isolates from commercial sour/saison/lambic beers) and 2 wine strains of ''B. bruxellensis''. Fermentis US-05 and the BSI Drei were used as controls. Each strain was fermented in autoclaved 100% 2-row malt wort at a starting gravity of 1.050 and fermented at 15°C (59°F) versus 22.5°C (72.5°F) for 28 days. The pitching rate was 1.2 x 10<sup>7</sup> cells/mL. Each strain was genetically tested to ensure their species was correctly identified and that they were genetically distinct from each other <ref name="Tyrawa_2019">[https://onlinelibrary.wiley.com/doi/full/10.1002/jib.565 The temperature dependent functionality of Brettanomyces bruxellensis strains in wort fermentations. Caroline Tyrawa, Richard Preiss, Meagan Armstrong, George van der Merwe. 2019. DOI: https://doi.org/10.1002/jib.565.]</ref>. The fermentation temperature of 30°C (86°F) was also briefly examined, but they were described as "smelling terrible" by Richard Preiss, and so were discarded from the study <ref name="Tyrawa_2017">[https://www.facebook.com/groups/MilkTheFunk/permalink/1285391951489016/ "Funky can be Great: Brettanomyces bruxellensis Beer Fermentations" (poster for study). Caroline Tyrawa, Richard Preiss, and George van der Merwe. 2017.] </ref>.
Their results showed that there is a vast diversity in how temperature effects attenuation for different strains of ''B. bruxellensis''. In general, the cooler 15°C (59°F) fermentation temperature slowed the attenuation rate for most strains. The US-05 attenuated the most at both temperatures, with only one saison strain matching that attenuation level when fermented at 22.5°C (72.5°F). This same strain, which was isolated from a commercial USA saison beer, and the BSI Drei strains had fast attenuation rates that were comparative to the US-05 fermentation at both temperatures, while the other strains had lag times of 8-10 days at 15°C (59°F) or 2-4 days at 22.5°C (72.5°F). Additionally, the colder temperature resulted in a wide variance between strains and their ability to ferment different types of sugars. Glucose and fructose were the only sugars fermented by all strains at the lower fermentation temperature by all of the strains, with a lot of variation for fructose, sucrose, maltose, maltotriose, cellobiose, and maltodextrin. Only BSI Drei and both of the wine strains were able to ferment cellobiose at the colder fermentation temperature (several of the saison strains began fermenting cellobiose at the warmer temperature), indicating that colder temperatures can greatly limit or even eliminate the ability to ferment cellobiose in most strains, and maybe the environment from which the strains were isolated from determines the efficiency to ferment different types of sugars for different strains of ''B. bruxellensis'' <ref name="Tyrawa_2019" />.
At 15°C (59°F), none of the ''Brettanomyces'' strains could match the US-05 attenuation, with most of them falling to around 50-25% less final attenuation after 28 days, and one of the wine strains and one of the USA saison strains fermented almost nothing at all. Still, this data showed that some beer strains of ''B. bruxellensis'' can ferment at lower temperatures. Interestingly, one of the wine strains was almost unaffected by the difference in fermentation temperature; it only lagged for a couple of days longer in the colder 15°C (59°F) fermentation temperature versus the warmer 22.5°C (72.5°F) fermentation temperature <ref name="Tyrawa_2019" />.