National Homebrew Club Ireland

Yes, I know it's from Horst, but it's also from the Uflecku brewer and Weyermann.
http://www.brewersassociation.org/pages/business-tools/publications/the-new-brewer/online-extras/show?title=style-spotlight-bohemian-dunkel

I've never seen a brewery give the EXACT malts and exact percentages, temperatures, times; all recipe and all process details like this before, it's pretty great!
This beer is also an unfiltered lager so perfect for home brewing!


Grist

• 50% Floor malted Czech Pilsner (May be called pale in the Czech Republic but it's CERTAINLY NOT UK or American Pale malt; the variety, process and color indicate that it's a pilsner lager malt) Malt (the Bojos variety is what U Flecku uses) - 1.8L
• 30% Weyermann Light Munich (Munich I) - 6L
• 15% Weyermann Caramunich II - 45.5L
• 5% Weyermann Carafa II - 430L

Mash Process
Prague has pretty soft water

Do NOT include the Carafa II malt in the grist when you mash in; add it with the second decoction if you brew this as a decoction; if you're doing an infusion mash, sub the floor malted pilsner malt for well modified Continental pilsner malt and add the carafa II with 10 minutes left to the mash

Mash in at a water to grist ratio of 3 liters per kg @ acid rest temps of 38C -hold here for 30 minutes (even though Prague's water is pretty soft, the acid rest is good because the pilsner malt is undermodified and the protein degrading enzymes actually prefer a thicker mash at a slightly lower ph)

Then add enough 80C water to bring the mash up to 52C for a protein rest (this is how U Flecku does it; I think this adds way too much water and I'd either just step mash with external heat or add a smaller quantity of boiling water to get up to 52C, personally)

After a 30 minute protein rest, pull your first thick decoction (1/3 of the grain portion of the mash) -hold the decocted portion at 64C for 10 minutes before raising up to 72C and holding for another 10 minutes, then raise up to boil for 10 more minutes and add back to the main batch (when it gets to boiling temps start lightly stirring to prevent burning)

-When you add decoction #1 back to the main batch it should raise the temp to 65C -hold here for 30 min then pull your 2nd decoction the same as the first (1/3 of the thick portion of the mash)

For decotion #2 just raise the temp to 72C for 10 minutes, then boil for 10 minutes while stirring and add back to the main batch

-Add your Carafa II now and mix thoroughly, and vorlauf for 10 min, then run-off to the kettle

Do a triple batch sparge with your sparge water (the water won't cover the grain) --I don't get the weird Czech and old German sparging method; this is my closest approximation

Note: If you follow U Flecku's method you'll end up with a very liquidy mash and you won't have much liquid left for the sparge, but if you read ahead below you'll see that this is a 2 hour boil so you actually WANT the extra sparge water because you'll be boiling more liquid off.


Boil
Boil for 2 hours

Target 28 IBUs, but the directions on the site aren't good for this; you'll have to use your brewing software
Split your 3 hop additions into equal portions

Boil for the first 30 minutes with no hops, then do a 90 minute boil for your first bittering addition; with 60 min left in the boil add your flavor hops and then the aroma hops at flameout
-Saaz hops for all additions

Fermentation
Use a lager strain (I'd use German because the popular Czech strains are big diacetyl producers and lager strains only have about 1% genetic variation anyway)

Pitch cold (8C) after giving the beer plenty of O2 (and transfering off of the trub/cold break) and ferment at 10C for 2 weeks then raise the temp to 12C for 1 day and 15C for another day, then slowly chill to 1-3C for 4 weeks.

I brewed this last year. I did a single infusion but would probably do a protein rest and FWH if doing again.

I used WLP800 and I fermented at 12 - 14 out of the fridge and lagered at 2 to 4. I found this was better for diacetyl than a longer primary at a lower temp albeit on a lighter coloured beer. I saw Graham Wheeler says that Czech lagers are fermented a bit warmer than Germans so it's something to considered.

There's also a similarish but less detailed recipe in the Hops book.

Quote from: Il Tubo on August 10, 2013, 11:01:51 PM
Will yeast get going at 8C? Will it get going quick enough to finish out in 2 weeks? Even at 11C my lagers take 2.5 weeks.

It will if you have enough yeast and healthy yeast.  You need a LOT of yeast for lagers and even more for colder fermented lagers.  They need a lot of oxygen, too.



Adam

Quote from: mr happy on August 11, 2013, 10:02:32 AM
I brewed this last year. I did a single infusion but would probably do a protein rest and FWH if doing again.

I used WLP800 and I fermented at 12 - 14 out of the fridge and lagered at 2 to 4. I found this was better for diacetyl than a longer primary at a lower temp albeit on a lighter coloured beer. I saw Graham Wheeler says that Czech lagers are fermented a bit warmer than Germans so it's something to considered.

There's also a similarish but less detailed recipe in the Hops book.

The traditional fermentation profiles involve pitching yeast SUPER cold, and fermenting very low on the temp, NO diacetyl rest, and then a 60-90 day lagering period that you get to by dropping from primary fermentation temps only 2 degrees a day.  -This is straight from the Pilsner Urquell traditional fermentation profile.


The BP Style book on Pilsner lists the modern (ish) Czech lagers as the most likely to use long decoction mashes and low and slow fermentation and lagering, and shows the Germans adopting more of the modern lager techniques that include single decoction or step mashing and shorter fermentations and lagering periods with diacetyl rests; the Danish, Dutch, and Scandanivians are then closer still to modern American lager brewing techniques and include adjuncts and even shorter and warmer fermentations with shorter lagering.  The Czech pilsners have the highest hopping rates (you can do that with super soft water and super low AA hop varieties (Zatec/Saaz); and the German pilsners with lower hop rates than the Czechs but obviously all malt grists, like the Czechs and the same or higher PERCEPTION of bitterness than the Czech versions because of the water chemistry differences and lower FG.  --If you "believe in" style guidelines, that is.  ; )

So plenty of sources contradicting Graham Wheeler on this one.

Adam

It's also worth noting that no traditional or modern lager practice ANYWHERE pitches lager yeast warm like some home brewers do.  -If the mega breweries don't even do it to save time, you REALLY don't want to cheat that bad.

Pitching lager yeast warm makes for a fruity ale-like lager and extra diacetyl. (I can say this with some experience now.)



Adam

Hi Adam,

You called me there. :'(

I made my last post while on holidays and I didn't have my notes - I did pitch cold (basically in a fridge at 8 degrees) but I brought it out after a couple of days (primary not complete) so I could use the fridge to lager something else. I let it run at ambient temp of 12 - 14 for a while before  lagering (much later than I'd have liked.)

Initially I thought I'd destroyed it but in the end it was definitely the best lager I've done to date with WLP 800 which is pretty weird compared to some of the German lager yeasts.

Now, I think the fact that it had some dark malts in there and that I pitched more than half of the cake from a previous Boh Pilz probably helped, a lot, but it had much less diacetyl than 3 - 4 pilz I'd done pitching and fermenting cold with the same yeast.

Quote from: Il Tubo on August 24, 2013, 11:40:13 AM

Quote from: biertourist on August 14, 2013, 09:33:35 PM
It's also worth noting that no traditional or modern lager practice ANYWHERE pitches lager yeast warm like some home brewers do.  -If the mega breweries don't even do it to save time, you REALLY don't want to cheat that bad.

Read up on WLP925 (http://www.whitelabs.com/yeast/wlp925-hp-lager-yeast) and then say that again!

Been trying to get hold of it as I ferment partially under pressure, but the minimum order is 40 vials.

Wow!  That is a freakishly weird sounding yeast strain!

Adam