Before discussing the new development, it is worth recapping the differences between lager and ales. Both are “beers,” with the difference resting on microbiology and the type of yeast used.
In the mycological world there are ale yeasts (which are diverse and this diversity leads to different flavors) and lager yeasts (here there are fewer types.) The yeast used affects the temperature at which the beer is fermented. The yeasts used to make ales are more robust and they can be fermented at warmer; whereas lagers are fermented at cooler temperatures. Chemically, the cooler temperature leads to fewer esters and less aroma. To counterbalance this, some would argue that lagers are smoother to drink than ales, even if they don’t taste as nice.
Some research has centered on using flow cytometry, a method where lasers are used to scan liquids and assess yeast cell numbers, to find yeasts suitable for lager that are more robust to higher temperatures; other branches of research are charting the evolution of yeast in order to genetically create new yeasts suitable for lager brewing.
This latter point is the basis of the new research. The new research starts with the point that lager yeasts arose from crosses between two parent yeasts: Saccharomyces cerevisiae, and S. eubayanus. The process of getting an effective cross is variable, leading to several substandard yeasts. A research team have figured out that if they were able to create more crosses between S. cerevisiae and S. eubayanus, which could lead to novel hybrids, then they could produce more diverse lager yeasts, which would, in turn, lead to more diverse lager beers.
Through genetic matching, the research group have created two hybrid yeasts that are said to be good for fermentation. Initial studies suggest that it is possible to create lager beers that are more different from each other. If this can be developed, the lager range could become far more diverse and edge close to the diversity offered by ales.
The research was conducted at VIB/KU Leuven and the findings are published in the journal Applied and Environmental Microbiology. The paper is titled “Large Set of Newly Created Interspecific Saccharomyces Hybrids Increases Aromtic Diversity in Lager Beers.”
