Back to Bohemia

As I mentioned in Monday's general post about Devils Backbone, I spent Saturday with their brewing team. The project in hand was to brew a replica of the original 1842 recipe used by grumpy old Josef Groll to create what became Pilsner Urquell. I first heard about their plans for this beer back when I was browsing Jason's blog in the light of the magnificent 1904 Stout (please, please make more!), and patiently I waited. Each month Devils Backbone send out a newsletter to those who have signed up, and on receiving it earlier this month I replied, simply asking when the pilsner was coming? Following a few emails between Jason and I, he very graciously invited me to come out and help brew, so, of course, I jumped at the chance and cleared my schedule.

At 8 o'clock on Saturday morning I rolled up to the brewery, or rather, was driven by Mrs Velkyal as she needed the car to go rowing, to be met by Jason, and bags of milled grain filling the brewhouse with that gorgeous malt aroma. Eventually we would be joined by Jason's assistant, Aaron, and coming in and out pretty much all day was Heidi, who was taking photos and making a video. Jason's brewhouse is German designed and built, although in a former life it was in Japan. Being German built, there are three vessels rather than two, the usual mash tun/brew kettle and lauter tun being joined by the decoction kettle. In keeping with the plan to be authentic as possible, we would be doing a triple decoction  mash, which takes about 3 hours rather than the more common 90 minute infusion mash.

Just briefly, though I imagine most of you know how decoction mashing works, essentially you bring the main mash to a predefined temperature, pull off a portion of the mash into the decoction kettle, bring that to the boil and then return the decoction to the main mash, which raises the mash temperature and creates Maillard reactions. Obviously for a triple decoction you do this three times, each at a higher temperature than the last. Entirely oversimplified I know, but there we go.

With regard to the recipe, Jason was using an article in The New Brewer magazine as his guide, which called for Bohemian Pilsner malt, in Jason's case floor malted from Weyermann, acidulated malt and a touch of light caramel malt (if I recall properly, I didn't take notes, I was too busy being awed at brewing with a champion brewer). The hops? Well to quote Connor McLeod, "there can be only one", Czech Saaz. One of the things I was really interested in was to see the water profile. Plzeň is famous for it's incredibly soft water, but to my surprise this wasn't to be an issue, because the well from which Devils Backbone draws its liquor is actually softer than Plzeň! For yeast, Jason stuck with the Augustiner lager yeast he uses, which really adds to the authenticity because it was a Bavarian yeast that first fermented the sugars in the wort that gave birth to the pilsner style lager. It was my pleasure then to get the process started by chucking in the first bag of milled Bohemian Pilsner malt.

The mash took about 3 and a half hours rather than the usual three, mainly because the decoction kettle wasn't heating the decoction quick enough, soon fixed though with a good whack of a hammer - recalling the comment of another brewer I know describing his job as "1 part artist, 1 part scientist, 1 part handyman". To celebrate the first decoction we popped open a bottle of Budvar, the second was marked with Devils Backbone's Vienna Lager, the third with one of Aaron's recipes Reilly's Rye, which was very nice. With the three decoctions done, the mash was pumped over to the lauter tun to be sparged. The picture below shows the first runnings of the wort back into the brewing kettle.

During the sparging process we popped into the bar for some lunch, some more samples - the highlight being for me the UK IPA and their Congo Pale Ale, a Belgian IPA which was distinctively champagne like. Eventually though we had 11.5 hectolitres of wort, measuring at that point 11.5° Plato, correctly predicted by Aaron. Once the boil was on, and it was a vigorous boil, in with the first round of hops - ah the smell of Saaz. I am sure I am entirely biased, but Saaz is one of my favourite hops, wonderful aroma, great flavour in the beer. To mark the first and second hop additions, I pulled out a bottle of the barley wine I brewed last November, of which only 13 bottles remain (from an original batch of 18 that is). Both Jason and Aaron were very complementary about the beer, and given it's marked hoppiness, I may have miscategorised it in the recent Dominion Cup. The third hop addition was heralded with their Scottish ale, Ale of Fergus, to which I alluded on Monday, along with the comment that they don't normally mark all the stages of the process with a toast - a practice I fear I would institute if I had my own brewery!

Obviously in between stages Jason and Aaron weren't just sitting around twiddling their thumbs, there being plenty of jobs to be done, such as sanitising the fermenting vessel, harvesting the yeast, preparing for the next days brewing by milling the grain. With everything done to prepare for the wort, it was pumped through the heat exchanger and into the waiting fermenter. I was intrigued to see how they would pitch the yeast, basically as the wort is being pumped into the fermenter, the yeast is pumped into the same hose through a valve, while aeration is achieved with a jet of filtered air rather than pure oxygen. When the final gravity measurement was taken, it read 12.5° Plato - just right for a Bohemian Pilsner.

And there it is, Devils Backbone's replica 1842 Pilsner. When the fermentation is about 1° Plato from the target, the airlocks will be closed and the remaining CO2 created will carbonate the beer, a process called "spunding". Under pressure, the beer will then be transferred to a lagering tank to sit for at least 30 days, before again being moved, under pressure, to one of the serving tanks.

I want to thank Jason and Aaron for having me along to take part in the brewing process. it was a fantastic day and we have discussed doing another brew day together. In the meantime I will wait patiently for what I hope will be a wonderful drop of lager that I will fill every growler I own with. Cheers!