Foster Barret, Tyrawa Caroline, Ozsahin Emine, Lubberts Mark, Krogerus Kristoffer, Preiss Richard, van der Merwe George
Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON, Canada.
VTT Technical Research Centre of Finland, Espoo, Finland.
Front Microbiol. 2022 Mar 16;13:747546. doi: 10.3389/fmicb.2022.747546. eCollection 2022.
Traditional Norwegian Farmhouse ale yeasts, also known as kveik, have captured the attention of the brewing community in recent years. Kveik were recently reported as fast fermenting thermo- and ethanol tolerant yeasts with the capacity to produce a variety of interesting flavor metabolites. They are a genetically distinct group of domesticated beer yeasts of admixed origin with one parent from the "Beer 1" clade and the other unknown. While kveik are known to ferment wort efficiently at warmer temperatures, their range of fermentation temperatures and corresponding fermentation efficiencies, remain uncharacterized. In addition, the characteristics responsible for their increased thermotolerance remain largely unknown. Here we demonstrate variation in kveik strains at a wide range of fermentation temperatures and show not all kveik strains are equal in fermentation performance and stress tolerance. Furthermore, we uncovered an increased capacity of kveik strains to accumulate intracellular trehalose, which likely contributes to their increased thermo- and ethanol tolerances. Taken together our results present a clearer picture of the future opportunities presented by Norwegian kveik yeasts and offer further insight into their applications in brewing.
传统的挪威农舍艾尔酵母,也被称为“克维客”(kveik),近年来引起了酿造界的关注。最近有报道称,克维客是快速发酵、耐热且耐乙醇的酵母,能够产生多种有趣的风味代谢物。它们是一组基因独特的驯化啤酒酵母,起源混合,一个亲本来自“啤酒1”进化枝,另一个亲本未知。虽然已知克维客在较高温度下能有效发酵麦芽汁,但其发酵温度范围和相应的发酵效率仍未得到表征。此外,导致其耐热性增强的特性在很大程度上仍不为人知。在此,我们展示了克维客菌株在广泛发酵温度下的差异,并表明并非所有克维客菌株在发酵性能和应激耐受性方面都相同。此外,我们发现克维客菌株积累细胞内海藻糖的能力增强,这可能有助于其耐热性和耐乙醇性的提高。综合来看,我们的结果更清楚地展现了挪威克维客酵母未来的应用前景,并为其在酿造中的应用提供了进一步的见解。