Brew #41: Bohemian Pilsener

This beer is my first ever pilsener, or pale lager for that matter. I used a lot of hops, so I expect it to be hoppy, quite bitter and really aromatic. It wasn't intended to be like an average commercial pilsener, but something more traditional and with a lot more punch. The beer is within the style guidelines, except perhaps for the aroma hops of which there are a lot.

In an interview with Charlie Papazian, by the generous people at Basic Brewing Radio, he said that it was possible to achieve much the same kind of malty flavour produced by traditional decoction mashing by instead adding 3-4% aromatic malt to the mash. So in this beer there is 200g of melanoidin malt. I hope that that will provide a richer malt complexity than just what pilsener malt will add.

Pale lagers are quite sensitive and not able to hide flaws very well. It is supposedly hard to make a good clean lager because of this. So from what I've gathered the devil is in the details. Here are some of the things that I tried to follow when making this pilsener:

• Use lots of vital yeast
• Ferment cold to get a clean fermentation profile
• Get rid of the hops and the break material (mostly proteins)

To brew a good lager you need a lot of yeast, thus a really big yeast starter is neccessary. For my ales of medium gravity I usually make 1 liter yeast starters from a single vial. For this one I made a 3.5 liter starter from two vials. Given that the yeast was quite old I was a bit sceptical and planned to use Saflager W-34/70 as a backup if it didn't wake up. I was wrong (read: lucky). The yeast starter was surprisingly vigorous. Liquid yeast can survive a while, especially if stored properly. Having said that, I know that is always best to use fresh yeast. I need work on my yeast logistics so that the yeast is as fresh as possible.

The beer is fermenting in the fridge between 9.2 and 10.2C. I guess I would have used an even colder setting on my thermostat, but from watching how it behaves I've seen the temperature fall down to 8.0C before it gets warmer. The reason might have something to do with where the thermostat sensor is located. Anyway, this should give a pretty clean fermentation profile.

Once the wort was chilled and transferred into the fermenter I placed it in the fridge for about 6 hours (while I was brewing the next beer). I also poured out half of the yeast starter and added fresh wort on top of it. During this time the temperature had reached the target temperature and most of the hops and break material had dropped to the bottom of the fermenter. I then siphoned the clear beer into another sanitized fermenter leaving the non-desired material behind. The goal was to not let the fermenting beer pick up any off-flavours from it. I then added the now vigorous yeast starter to the fermenter. The airlock started moving within an hour. So, the fermentation got off to a good start. We'll see how it ends up. I'm optimistic.

The batch was brewed 2007-01-21.

Style:
Bohemian Pilsener
Type:
All grain, batch sparge
Colour:
11 EBC (Golden)
Bitterness:
44 IBU
Malts:
6300g Pilsener malt
200g Carapils
200g Melanoidin malt
Mash:
65C, 60 min
76C, 10 min (mashout)
66% efficiency
Hops:
15g Warrior pellets 13.8%, 60 min
50g Liberty pellets 4.0%, 60 min
50g Saaz pellets 3.9%, 15 min
50g Liberty pellets 4.0%, 5 min
50g Saaz pellets 3.9%, 1 min
Yeast:
White Labs WLP 802 Czech Budejovice Lager, 2 vials, best before 2006-07-08 and 2006-10-30, 3.5 liter starter
Boil:
90 min
OG: 1.053 FG: 1.013 (estimated)