Bourbon Barrel Chocolate Imperial Coffee Stout

My Local Home Brew Shop (Weak Knee) recently acquired another whiskey barrel for a group fill.  I have enjoyed the process of the first one enough to jump on board with this one.  For this round we will be making a stronger beer to stand up to the stronger whiskey and oak flavors of the first use barrel:  a Chocolate Imperial Coffee Stout

This will be the first beer I have brewed with either chocolate or coffee.  Cocoa powder will be added at the end of the boil and then at the start of secondary in the barrel.  We will then age the beer in the barrel for 6 to 8 months before steeping the coffee.

It's a complicated recipe, with a lot of specialty malts, and then with the chocolate, oak, whiskey, and coffee added to the mix.  I think the flavors are of the sort that obviously work well together so I'm pretty confident that we'll end up with a pretty good final product.  The main concern I have is that if the FG ends up too low for enough of our batches that the oak, chocolate, whiskey, and roasted malt could take on too sharp an edge.  My piece of the batch is less than 1/10th of the beer that will be in the barrel so there's nothing I can do to prevent this - hopefully everyone will hit the target FG of 1.019.

We are scheduled to put this beer into the barrel on 4/18 so I'll have just under 3 week to get it fermented out.  I don't expect any issues with this.  I'm really excited to get to do another one of these.

As a last minute decision, based on the huge grain bill and a fairly low projected efficiency, I decided to try my hand at a Parti-Gyle beer which is a second, weaker, beer using the sugars remaining the mash after the first big beer is mashed out.  This will be a Dark Chocolate Sour.

Recipe Details:

• Grain:
• 9 lbs 2 Row
• 2 lbs Roasted Barley
• 2 lbs Chocolate malt
• 1 lb 8 oz Munich
• 1 lb Crystal 40L
• 12 oz Aromatic
• 12 oz Carapils
• 4 oz Black Patent
• Hops:
• 1 oz Cascade (Pellet, 7.2% AA) at 60 min
• 1 oz Fuggle (Pellet, 4.2% AA) at 30 min
• 1 oz Fuggle (Pellet, 4.2% AA) at 15 min
• Yeast:
• Wyeast 1098 British Ale yeast
• Red Star Premier Cuvee (For Priming)
• Water:
• 10 gal spring water
• 1 tsp Calcium Chloride
• 1 tsp Gypsum
• 1 tsp Irish Moss at 15 min
• Extras:
• 1st use Bourbon Barrel 3 oz of Jack Daniels Soaked Oak Cubes
• 5 Tbsp Hershey's Special Dark Chocolate Powder at 5 min
• 5 Tbsp Hershey's Special Dark Chocolate Powder in secondary
• 750 mL of Jim Beam Extra Aged Bourbon Whiskey

Process Details:

• Batch Size:
• 5 gal (Target 5.25 gal)
• Mash:
• 155 F for 70 min (Target 153 F for 60 min)
• Boil:
• 60 min (Target 60 min)
• Fermentation Temperature:
• Ambient Basement Temps (60 to 63 F)
• Primary Duration:
• 5 Weeks
• Secondary Duration:
• NA
• Barrel Aging Duration Secondary on Oak:
• 6 to 8 months
• Coffee Steeping Duration:
• NA - Decided not to use coffee on this batch

Results:

• OG:
• 1.083 (Target 1.077)
• Efficiency:
• 70% (Target 68%)
• FG:
• 1.008 (Target 1.019)
• Apparent Attenuation:
• 90% (Target 74%)
• ABV:
• 9.84% (Target 7.61%)

Brewing Notes:

• 3/28/15 - Made a 1 liter yeast starter with 5.5 oz of LME.  Added 1/8th tsp of yeast nutrient.  Left on the stir plate to propagate over then next 24 hrs

• 3/29/15 - Brew day - 8:00 AM to 12:30 PM including setup (started the Parti-Gyle after this):
• Heated 8 gal of strike water to 185 F (assuming 20 degree loss to the mash tun, a 1.5 ratio of water to grain, and that the grain was at 60 F) - took 40 min
• Added Gypsum and CaCl to the kettle as it was heating up
• Transferred 28 qt of strike water to the mash tun and let the temp settle for 10 min - temp settled out to 178 F
• Added the grain and stirred in (there is a ton of dark malt in this one - the liquid was inky black)

• Measured the temp after 10 min as 160 F.  I stirred to cool until it got down to 156 F.  Restarted the clock on the mash at this point.
• Gave the mash a stir at 30 min - temp was down to 155 F
• Brought 6 gal up to 185 F for the Batch Sparge (and Parti-Gyle Beer) - took 25 min
• After 60 min the mash was at 154 F
• Stirred, vorlaufed, and drained (slowly at first and then at full speed)
• Added 3 gal batch sparge, stirred, vorlaufed, and drained.  Flow was being inhibited by the mash for some reason.  I have to stir and then blow air into the manifold to get a decent flow
• Collected 7.25 gal of pre-boil volume (right on target)
• Brought to a boil - took 15 min
• Added the 60 min hops once the hot break had settled down
• At 6.25 gal the 30 min hops were added
• At 5.75 gal the 15 min hops and irish moss were added
• Added the chocolate with about 5 min left in the boil - I stirred well to help the chocolate dissolve

• Added the wort chiller at flameout to sanitize
• Chilled down to 65 F - took 10 min
• Drained into the fermentor - aerating by letting the wort fall into the bucket
• Collected just about 5 gal (slightly less)
• Pitched the entire starter into the beer - it looked like it was pretty much at the height of it's fermentation activity which should get me a quick start
• Gravity was measured as 1.082 at 65 F which is about 1.083.  The sample had a nice balance between roast and chocolate.  The chocolate seemed to be at a nice level (not too strong which I was thinking might be an issue with 5 heaping tablespoons)
• Setup the fermentor with an airlock as I have quite a bit of headspace
• 3/30/15 - The airlock was bubbling this evening
• 4/9/15 - After a little less than 2 weeks in the fermentor the beer is down to 1.038.  I expected it to be quite a bit lower than that but I guess the large percentage of specialty malt and higher than target mash temp played a factor.  The beer is still bubbling a bit so maybe it will come down a few more points.  It has a nice chocolate flavor along with a firm roast.  The sweetness of the beer doesn't seem out of place - the alcohol level is a bit off the "Imperial" mark though.  This beer will really just be one in a larger blend so it's probably not that big a deal.
• 4/18/15 - Measured the gravity again today - still 1.038.  I guess it's done.  Very surprised at this (only 52% attenuation).  Drove it to homebrew store for transfer into the barrel which will happen next week.

• 5/2/15 - My beer was rejected for the barrel due to a suspected infection.  The beer had accumulated an oily film which could be a pellicle.  It doesn't really look like the pellicle I've seen on any of my deliberately infected beers.  I suspect that it isn't infected and that this film is actually a result of the chocolate as the beer seemed to have accumulated this film very soon after primary fermentation completed (much quicker than I would expect an infection to make itself known).  I did some research and found this forum discussion that seems to be documenting the same observation.  Based on this I felt safe transferring the beer to secondary for monitoring/aging.  I have 1.5 oz of oak cubes soaking in Jack Daniels which I plan on adding to this beer in a couple weeks.  I have been offered some of the beer from the barrel even though I haven't contributed anything to it which is very generous of the group.  Not sure I'll take them up on that but I think it would be very interesting to compare the beer aged in the barrel to this secondary oaked version.

• 5/16/15 - Added whiskey soaked oak cubes to the secondary.  I didn't include any of the whiskey it had been soaking in as it had turned a dark brown and tasted very woody.  Just to note:  I had soaked 1.5 oz of oak in the whiskey.  A few days in the cubes had soaked up quite a bit of the liquid so I topped it off.  They had been floating initially but they eventually sunk to the bottom.  After two weeks of soaking they weigh about 2.5 oz.  I decided to only transfer 1.5 oz of that to the beer.  I will continue to soak the remaining cubes and add them later if it seems like the beer needs it.

• 10/11/15 - Checked on this beer after almost 5 months.  Still no pellicle or other visible sign of infection.  Measured a sample as 1.012 which is shocking to me as the beer had previously stopped at 1.038 (measured twice - a week apart).  I have to eat some crow - there is a definite acidity to the beer that suggests some lactic acid bacterial infection.  The barrel team made the correct choice in booting my beer.  Overall I'd say the beer still holds together pretty well.  Even though is pretty dry the roast flavor doesn't really contribute any out-of-balance astringency.  The chocolate provides a nice dimension and the slight sourness in the finish just provides another interesting component to the flavor.   I don't get any whiskey or oak in the flavor which surprises me.  Given this new development I am going to skip the planned coffee addition.  I will give this beer another 3 months of aging before I check it again to get a feel for whether I have hit a stable gravity.
• 4/17/16 - Pulled another sample of this beer to taste.  I'm not sure what I was thinking with the last sample because with this one I'm not really getting any acidity.  No pellicle on the beer either.  I don't think this beer is infected after all.  It has a bit of fruitiness along with roast and chocolate flavors.  It tastes really nice actually.  The whiskey and oak flavors barely come through.  I am going to put in another 5 table spoons of chocolate powder (sanitized in 1 cup of boiling water) and another 1.5 oz of whiskey soaked oak cubes and let this age a bit longer.
• 8/5/17 - This beer has spent the last year or so in my wife's townhouse basement.  It had a film on the top like it had previously - assuming this was just the chocolate rather than a pellicle.  I am going to bottle today!  Measured the gravity as 1.008.  The beer has a subtle chocolate character along with quite a bit of oak flavor.  The oak provides a bit of sharpness (which may have been what I mistook for acidity initially).  It's a wine-like oak character I would say - it may be that I'm tasting the tannins.  There isn't a lot of whiskey in the flavor profile.  I tried blending some Jack Daniels whiskey into half a cup of the beer and found that 1-2 tsp added enough whiskey character to be interesting.  This amounts to a full 750 mL bottle.  Based on this I am adding a full bottle of whiskey to the beer at bottling.  I chose Jim Beam "Extra Aged" Bourbon for this.  Bottled with a pack of Red Star Premier Cuvee wine yeast.  Added 3 oz of priming sugar.  Ended up with 4.5 gal of beer which got me 46 12 oz bottles.

Lessons Learned:

1. Two batches in a weekend (even a long weekend) is too much brewing for me.  Two and a half batches like I did today is way too much.  I'm exhausted.
2. Brewing with chocolate is fun but the powder is pretty darn messy.  Cleaning the kettle was a pain.  I imagine cleaning the fermentor out is also going to be a pain.
3. FG is a product of mash temp, yeast, and grain bill.  In order to predict FG you need to understand the impact of all three of those variables (and there may be others as well).  I'm not sure there's anything to be done to get an accurate prediction of a recipe the first time you brew it.  This recipe has an unusually high percentage of specialty malt (48%) which made the prediction even more difficult.  Never would have guessed I'd only get 52% attenuation even with this grain bill. 
4. I oaked this batch for 2 years.  The oak character is kind of sharp and "wine-like.  I think I would have been better off charring the oak prior to adding it for aging.  This could produced some more Whiskey like flavors.  I think I'll do that next time I try an oak aged dark beer.