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[https://www.biorxiv.org/content/10.1101/2021.07.26.453768v1 Foster et al. (2021)] published similar findings for 6 strains of kveik. All 6 strains tested (two Hornindal strains, one Laerdal strain, one Ebbegarden strain, one Granvin strain, and one Sigmund Voss strain) attenuated efficiently between 22 and 40°C. With the exception of Hornindal2, Ebbegarden, and Leardal strains, the other three kveik strains also performed well at 42°C. In comparison, none of the control strains (Cal ale, Vermont, Kolsch, and "St. Lucifer" from Escarpment Labs) attenuated well at 42°C. Out of the control strains, only the "St. Lucifer" from Escarpment Labs was able to attenuate at 40°C. This demonstrates kveiks' unique properties of being thermotolerant. The kveik strains were also generally able to ferment at lower temperatures. While most kveik strains attenuated similar to the Vermont and "St. Lucifer" controls at 15°C, Hornindal1 and Laerdal completed fermentations similar to the Kölsch and Cali strains. In addition, Hornindal1 completed a 12°C fermentation within 10 days. Overall, the kveik strains had a shorter lag phase and faster fermentation rates over a wide range of temperatures between 15-42°C, and they generally consumed glucose and maltose faster than the control strains at each of their optimal fermentation temperatures. With the exception of one of the Hornindal strains, maltotriose consumption slowed at the cooler temperatures (12°C) and was fastest with the Hornindal strains between 30-42°C. The Laerdal strain was inefficient at fermenting maltotriose (~50%) at all fermentation temperatures. In contrast, while the control strains could efficiently ferment maltotriose at their optimal fermentation temperatures (22-30°C), they were less efficient than the kveik strains outside of their optimal fermentation temperatures, once again demonstrating that some kveik strains can attenuate wort at a wider range of fermentation temperatures (both warmer and cooler) than some traditional ale strains <ref name="Foster_2021" />.
Foster et al. (2021) also discovered that the tested kveik strains produced much higher levels of trehalose, which is a carbohydrate used by yeast (and other organisms like frogs) to protect cells from freezing/thawing and higher temperatures. Unlike other brewing strains which break down trehalose at the end of fermentation, kveik keeps it. This might explain how kveik strains are able to tolerate higher temperatures, as well as why they can tolerate drying. It might also explain why kveik begins to ferment so quickly in fresh wort. Trehalose stores also cause yeast to not take up maltotriose, and this might explain why kveik strains tend not to consume maltotriose <ref name="Foster_2021" />.
====Temperature and Aromatic and Sensory Compounds====