Lug Wrench Brew: Frosty Fool, Eisbock

After an 18 month hiatus, Tom and I were finally able to strike up the propane burner together and brew our latest collaborative beer.  The prior collaborative brew was our Wheatwine Braggot, which was made back in November 2010.  So once all the kids and wives were asleep, we brewed up the base beer for what will become our Eisbock.

Aptly named after the April Fool's Day brewing session, this beer will represent the first collaborative beer where we did not pick the beer style - the readers did.  Three to four weeks prior to our planned brew session, we narrowed our interests down to six potential styles and then put it to a vote on the blog.  The idea was somewhat of a whim, but after we put the poll up, both Tom and I were incredibly energized by the number of participants that took part in the decision.  For a while, it looked like we might be brewing our first sour beer, but the Eisbock style made a surge and ultimately had the most votes.  The whole process might seem a little gimicky from the readers' perspective, but for Tom and I, it was very entertaining and enlightening to 'crowdsource' the style decision.  I would expect that we will do it again the next time we do a collaborative beer (although hopefully it won't be 18 more months away).

After the style was decided upon, choosing the recipe was somewhat a no-brainer.  Jamil Zainasheff's recipe and process is the only notable recipe for Eisbock that I have come across.  The grain bill and process described below should look familiar to anyone who is a disciple of Jamil's book.  However, accommodating the ~25 lbs of grain in my 5 gallon mash tun was going to be a problem.  Luckily, I was able to barter with another homebrew and friend (thanks Jeff H!) to score a larger capacity mash tun to get the deed done in.

At the time of this writing, the base beer is still bubbling away through primary fermentation.  Once its complete, I'll rack it to a corny keg and let it lager for 4-6 weeks before doing the icing process.  Assuming I remember to take some pictures, the icing process will most likely be the subject of a future blog post, which I will link back to here.

Below are the notes and recipe for the collaborative eisbock.  The notes will be updated as the beer continues to ferment, lager, get iced, aged, and be tasted.


Frosty Fool, Eisbock
(recipe modified from Jamil Zainasheff's Brewing Classic Styles)

Recipe Specifics
-----------------
Batch Size (Gal): 5.0
Total Grain (lbs): 24.5
OG: 1.086  (target: 1.088)
FG: 1.022 before icing; estimated to be 1.026 after icing
SRM: 14.9 before icing; no noticable color difference after icing
IBU: 28.0 (Rager)
ABV: ~8.5% before icing; ~10% after icing
Brewhouse Efficiency: 60% (dropped it to accommodate lower efficiency with big beers)
Wort Boil Time: 90 Minutes

Grain / Extract / Sugar
----------------------
13.5 lbs. Bohemian Pilsner Malt (Weyerman)
9.5 lbs. Munich Malt 10L (GlobalMalt)
1.25 lbs CaraMunich 40L

Hops
-------
0.5 oz Warrior Pellet Hops (15% AA) at 60 minutes
0.5 oz Hallertauer Pellet Hops (4% AA) at 30 minutes

Extras
-------
1.0 Tab Whirlfloc at 30 minutes
28 drops of Foam Control in the boil

Yeast
-------
Saflager S-189 (from a local brewpub), propagated up through two 2L starters

Mash Schedule
---------------
60 minutes at 152° F
Batch sparged to get 7 gallons in brew kettle

Notes
---------
Brewed on 4/1/12 by the Wallace Brothers.  Seventh collaborative session brew

Aeration was accomplished via an aquarium pump and diffusion stone, run for 30 minutes.  Foam Control was added to the carboy as needed during aeration.

Beer was about 53° F after aeration, so the carboy was placed inside the fermentation fridge (set point at 45° F) for ~8 hours before pitching yeast.

Pitched entire 2L starter when carboy was 43° F and placed the setpoint of the fermentation fridge to 46°F.

Activity kicked off in the carboy 48 hours after pitching yeast.

In order to help drive fermentation of the lager, I will be ramping the temperature up using Mike McDole's technique for driving lagers.  Also, given the OG of the beer, I will keep the initial fermentation temperatures lower than normal, as this sucker is going to throw off a lot of heat.

4/4/12 - Fermentation activity started with kreuzen forming.  Temp set at 46° F

4/6/12 - Fermentation going strong.  Raised temp set point to 48° F

4/7/12 - Fermentation still going strong.  Raised temp set point to 50° F

4/9/12 - Fermentation slowing slightly. Raised temp set point to 52° F

4/11/12 - Fermentation slowing more.  Raised temp set point to 55° F

4/20/12 - Fermentation continues to slow.  Raised temp set point to 60° F

4/26/12 - Fermentation almost complete.  Raised temp set point to 70° F

5/3/12 - Fermentation has been complete for a few days.  Cold crashed the beer by dropping the set point temperature down to 35° F.  The beer remained in the carboy until I got the chance to rack it off the lees and into a keg.

5/26/12 - Finally, I was able to transfer the beer off the yeast and into a sanitized keg (after ~3 weeks of lagering in the carboy).   The beer tastes very clean and has a stong malt intensity paired with a warming alcohol sweetness.  No detectable hot alcohols at all, which I am very pleased with.  The color, on the other hand, is fairly light - lighter than I would have wanted.  The icing should darken it a bit, but perhaps if we ever brew this again, we'd add in some coloring grains to darken it up a bit.  I'll let the beer lager for another 2-3 weeks before icing it.

6/19/12 - Completed the icing process by placing the keg in a freezer for 10 hours and then transfering the unfrozen liquid into a new keg while the frozen slush was left behind.  After measuring the volume of the left behind slush, we removed 3 quarts of liquid, thereby condensing the eisbock by 15%.   A description of the whole process can be found here.

2/24/13 - After 8 months of lagering in cold storage, we tasted the beer for the first time.  It is very clean with a sweet, rich malt character, although the sweetness does not linger into the aftertaste.  It may not be "over-the-top" enough to score well as an Eisbock, but the results are very pleasing.

4/8/13 - Samples the Frosty Fool beer were entered into the 2013 Ocean State Homebrew Competition, where the beer was awarded a silver medal in the Bock category.