Czech pilsner: the OG single malt-single hop beer. It’s caramelly, it’s malty, it’s hoppy, it’s a lager but it’s got some yeast character; it’s demanding to brew but it’s so, so easy to drink. It’s been too long since I’ve made one.
Speaking of yeast character: I recently attended the 2013 Rocky Mountain Microbrew Symposium, and on the topic of fermentation byproducts, diacetyl in Czech lagers came up. A presenter posited that Czech lagers didn’t always have diacetyl as an accepted stylistic component – it was, according to the presenter, when Pilsner Urquell shortened their lagering regimen from approximately 3 months at 33.5F to approximately 1 month at 33.5F (times are from the speaker’s presentation, and I got the temp from Jackson’s Beer Companion 2nd Ed., in which he says “the beer is said to be lagered for two to three months,” but this was in 1993 at the latest, so …). The upshot being that at that temp, there was no way the cells could reabsorb all of their nasty little vicinal diketone leavings in that short of a time, so the flavor threshold was crossed by the paragon of the genre, and at some subsequent point diacetyl was written into the style description. It’s been a long old time since I’ve done an analytical side-by-side, but I seem to remember differing levels of diacetyl from brand to brand in the Czech imports. Discuss.
A different talk at the RMMS dealt with craft lager brewing in general, but diacetyl came up again here. The regimen used by the presenter’s brewery was designed to produce a clean lager with quick turnaround – at a comparatively elevated primary temp range of roughly 50 to 55F (vs. the 42-43F cited by Jackson for Pilsner Urquell), vicinal diketones are produced and reduced quickly.
The wort is knocked out and inoculated at a temp that’s a good several degrees colder than the target fermentation range – since esters and other compounds undesirable in a lager are produced in the first 24-48 or so hours of fermentation, the cold start helps suppress their formation. The ferm temp is then allowed to rise into the low to mid 50s once the wort is at about 50-60% attenuation; this makes sure that both diacetyl reduction and attenuation complete in a timely fashion and – I think this is cool – obviates the need to slowly ratchet the temp down to lagering after the yeast is cropped – since its work is already done, you can just crash it straight down to 32-34F or what have you. Assuming you’re starting at 55F, this alone could shave weeks off a traditional lager fermentation schedule. Maturation time is also shortened, with the speaker citing standard-gravity lagers that can be ready for packaging in as little as 3 weeks (obviously this is highly dependent on the yeast strain and other factors).
Over the years, I have gravitated towards a pretty similar schedule for all my lagers that are not fermented with a sulfury fart-bomb yeast strain (I love you, but I’m looking at you, 2308 and 2042) with positive results, but it’s nice to have it validated by a dude in a brewery workshirt with Powerpoint cred. Discuss.
Anyway: new crop year whole Saaz (natch), 2nd generation Budvar yeast (washed), Moravian 2-row barley malted on the finest floors. And that’s pretty much it. I love how stripped-down and elemental this style is, and how the whole ends up being a good deal greater than the sum of its parts: fermentation really is magic.
But before the magic happens, I gotta dose out hops, weigh out the grist, actually harvest and wash the damn yeast, mix up some new sanitizer, check the propane supply, check the coffee supply, check the O2 supply, futz with a sticky QD, print out the brew sheet … I’m exhausted, and I haven’t even done the first decoction. Better get more coffee.
Brew day write up and recipe forthcoming. Nerds up, temps down.