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Doppelbock – BIAB

Doppelbock – BIAB

As an avid lover of German beers, I’ve been been a fan of the Doppelbock. Malty, fruity yet powerfully high in alcohol content. It’s a deceptive beer, easy drinking but packs a punch.

Naturally, this was a challenge for my system. I use a BIAB (Brew in a Bag) on my stove top. Although my 15 gallon Megapot can handle a high gravity beer, it would be a stretch to use a massive grain bill. I said what the hell and tried it out. One sore back and 6 months later, I was happy with the result but now am looking to improve.

The other barrier to entry for a doppelbock on a BIAB system is the historic german mashing method of decoction. The Decoction is when a portion of the mash (when the grain mixes with water) is pulled out and boiled it. The boiled mash is then added back into the main pot, raising the overall temperature and also imparting a more malty, caramel flavor. The mash that is pulled out is actually a rather dense mix of grain and water. Originally, I thought that the decoction would be solely wort but the grain imparts a lot of flavor.

The next trick is the fact that doppelbock, with it’s high alcohol content, usually requires several months of “lagering”. Lagering is allowing the beer to condition in cold temperatures and a challenge against my well known lack of patience.

First, I had to come up with a recipe. After some research, I landed on this:

19 lbs of Munich Malt
.5 lb CaraMunich
2 oz Tettnang hops
1 pack Bavarian Bock yeast (Wyeast 2206)

This resulted in one of my most challenging (and long) brew days yet.

Overall Brewing Entry Log

Start time: 11am
End time: 7:20pm
OG (Original Gravity): 1.081
FG (Final Gravity): 1.024

Decoction:
Pulled 3 gallons of the thick mash (both grain and liquid) and boiled it separately, then added back in.
The Bag was so heavy that I couldn’t lift it up without a second set of hands. This is very much the reason for the sore back and something I would not recommend. Definitely a limit of the BIAB process unless you have a pulley system or something.

One new technique I tried was recirculating. I would draw off some of the liquid and gently pour over the bag of grain during the mash several times. This increased the OG (original gravity, basically the higher it is the more potential for a higher alcohol beer).

I pitched the yeast at 58F after letting it cool down in the chest freezer.

After about 2 weeks, I had my first stuck fermentation. The beer hovered around halfway complete during the fermentation. I went to the store and bought 2 packs of liquid yeast (WLP833 german bock) and threw it in there to jumpstart it, which worked wonders.

In order to make room in my limited chest freezer, I also removed the beer and let it sit at room temperature for a week (70F). I then returned it to the chest freezer for another week in the 40F range.

Brewed: 1/21/16
Pitched more yeast: 2/5/16
Kegged: 2/28/16

Tasting Notes

Strong, malty with a bready flavor. Definitely higher notes of alcohol than I’d like. Hoping that with more time it might mellow out.

Overall not my best beer, but a good attempt at a doppelbock. I will update on version 2 and 3 especially changing up the variables of having more time at a lagering temperature.

10 Month Update

I really wished I took everyone’s advice to let this one age longer. After 7 months, it really hit it’s stride but by then I had most bottles already given away. This is one of those beers you need to let chill, literally, for a long time.