Posted on 09/25/2015 1:49:00 PM PDT by Red Badger
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 research is published in the September 25 Applied and Environmental Microbiology, a journal of the American Society for Microbiology.
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 differentlike lions and tigersas to make successful crosses rare.
"We figured that if we could create more crosses between S. cerevisiae and S. eubayanus, we would perhaps produce a set of more diverse lager yeasts, which could yield more diverse lager beers," said Verstrepen, who is Professor in Genetics and Genomics, University of Leuven and director of the VIB lab for Systems Biology, Leuven, Belgium. The researchers did their best to optimize growing conditions, hoping to encourage mating between the yeasts. To this end, they experimented with different temperatures and growing media.
"We were able to get some serious sexual action between our yeasts, which resulted in hundreds of new lager yeast strains," said Verstrepen. But of 31 new strains that they tested in small scale beer fermentations, only ten performed reasonably well in terms of speed of fermentation, and flavor. "Some were really bad," Verstrepen confesses.
They then tested the four best of these in full scale fermentations. "Two were magnificent," said Verstrepen. "They fermented more quickly than the commercially used reference lager yeast that we compared them to, and they produced really nice flavors."
More generally, "We found that the different lager yeasts that we created showed very different aroma profiles compared to today's commercially available lager yeasts," said Mertens, who was the paper's lead author. "This means that it now becomes possible to make lager beers that, like ale beers, are more different from each other, and this without the need to extensively change the production process."
Lager beers are fermented with S. pastorianus, which is a hybrid between S. cerevisiae and S. eubayanus, at temperatures generally between 8-15oC. They also have a lower alcohol content, 4-5.5 percent by volume. Ales are fermented by S. cerevisiae, at higher temperaturesusually between 15-25oC., and they tend to be stronger than lagers.
The research originated during one of the regular Friday evening beer tastings at the laboratory, in which students would taste and discuss five or six related beers. "One night, we tasted six Pilsner-type beers, and someone commented on how similar they were, much more so than beers of other types," said Verstrepen.
Explore further: Thanks, fruit flies, for that pleasing beer scent
Journal reference: Applied and Environmental Microbiology search and more info website
It is an acquired taste. I enjoy them now, but last year I felt the same about them as you do.
They also make a Caramel Porter which is excellent as well.
But in general, beer has become... beer. There is a same old base flavor that has grown stale to me. So I switched to Scotch and Irish Whiskys and other distilled spirits like various dark rums, Rye's and Bourbon too. Maybe I've consumed too many beers that are just boring.
Well I’m not a fan of IPAs, so I can’t offer anything specific. There’s only a few that are acceptable, but I don’t really remember brand/name. Have you tried any of the black IPAs? Or maybe a rye IPA, or Stone has some stuff that’s so excessively bad, it’s actually pretty good!
Not me, but I know there is one. It may not have been used recently.......................
Red_Devil 232 used to have a Home Brew ping list and would ping out a weekly "Beer 30" article.
Big ol void now, that is why I was trying to nudge you in.
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