Unlike ales, lager beers differ little in flavor. But now, by creating new crosses among the relevant yeasts, Kevin Verstrepen, PhD, Stijn Mertens, and their collaborators have opened up new horizons of taste.
The relative uniformity of flavor among lagers turned out to result in significant part from a lack of genetic diversity among the yeasts. Genetic studies showed that lager yeasts had resulted from just two crosses between the parent yeasts, Saccharomyces cerevisiae, and S. eubayanus. The problem was that the two yeast species are so different--like lions and tigers--as to make successful crosses rare.