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2016 Mellow Midnight Update


Well, here we are over a year later. For those that need caught up, I brewed a 12% Imperial Stout a little over a year ago, with a plan to age it on charred oak cubes for 12 months. The goal obviously being to see how well I could replicate the flavor of bourbon-barrel aged beers. I took pretty good notes during the process, since there was no way I could remember how things progressed over the twelve months. I typed everything in a Captain’s Log of sorts, so it’s easy to follow along.


January 17, 2016:

It’s been three weeks since I first tossed the charred oak cubes into this batch, and my curiosity is getting to me. I turned the keg over end-over-end to distribute the flavors, then cracked the keg open to take a sample. The aroma smells awesome, still mostly stout, hardly any wood. The flavor has some noticeable wood flavors, but not the bourbon barrel flavors I was hoping for. Much more oak-y, like if you licked a piece of oak. I’m not discouraged, but not thrilled either.


February 3, 2016:

It’s been another 2 and a half weeks, and some doubt has been creeping in. I’m worried that oak flavor might be getting stronger. So I crack the keg open again and draw another sample. My worries were confirmed. It’s REALLY oak-y. Both flavor and aroma. Not bourbony, just woody. I’m definitely concerned at this point, but there’s really nothing left to do but ride it out I guess. I purged the keg again with CO2. Moral is not high right now.


March 3, 2016

It’s been a month since the last tasting, and I’m again curious. I rolled the keg a couple times to distribute the contents, and took another sample. There’s HOPE!!! Those woody flavors are starting to fade, and there’s a very distinct bourbon flavor present. Nothing in the aroma, but you can definitely taste it. I’m not really sure what magic happened over the last month. It has been much warmer in the house (Phoenix had one of the hottest Februarys on record), so maybe that had something to do with it. My biggest concern at this point is whether this will progress too quickly. I guess I’ll have to continue tasting monthly to see.


April 1, 2016

Sheer coincidence this was April Fools day, as it just happened to be the first Friday of the month (trying to get on a schedule here.) I rolled the keg and gave it a sample. We’re definitely moving in the right direction. The bourbon flavor is getting stronger, and it’s present in the aroma now. There’s an a slight soy sauce aroma which i’m guessing is some oxidation. I can’t say I’m thrilled with that, but hopefully it doesn’t get stronger. The oaky/woody flavor is completely gone, which makes me very happy. You could almost pass this off as a barrel-aged stout at this point.

Lid on, and back into storage for now. I think I’ll wait until June before cracking back into this, I’m not as anxious as I was a couple months ago.


June 1, 2016

Summer is officially here, and after two long months, it’s time to crack open the keg and see what we’re working with. The first smell of the tasting glass tells the story, this is definitely working!!! There’s a nice mellow bourbon flavor that’s very noticeable in the aroma. The soy sauce aroma has faded, and the flavor is getting much closer to what I expect when I hear “barrel-aged”. As the beer has cleared up from sitting this long, I’m wishing I had added a little more roasted barley for color and flavor. The head is a rich tan, but definitely not the light brown you expect. I’ve decided to add an additional half ounce of charred oak cubes as well; they’ve been sitting in bourbon since December. After tasting some BCBS and Parabola lately, I think a little more barrel character will be a good thing. Nonetheless, I’m going to seal the keg up until August.


August 1, 2016

Well, I’m very curious to see how this tastes after adding the additional oak cubes, and the verdict is very good. This getting wonderfully close to what I want the final product to taste like. The beer is continuing to mellow out, and the bourbon barrel flavor is coming through really nicely. It’s now just a guessing game when to pull the beer off the oak at this point. I can’t say the additional oak cubes made a huge difference, but I guess that’s the challenge of barrel-aged beers. Part of me is ready to pull the beer now, but I’m going to check again in two months and see how we’re doing.


September 1, 2016

Two more months have gone by, and it’s time for another taste test. We’re getting very close. The barrel-aged flavor is continuing to increase, but the rate has really slowed down. At this point my only worry is that the flavor profile will somewhow take a turn for the worse. With that said, my patience has paid off so far. Lid back on for now, and CO2 purged.


November 27, 2016

Well, life gets busy, and sometimes you’re behind on stuff. I was supposed to check on this about a month ago, but I forgot. C’est la vie. But from tasting the beer now, I can tell from the first sip: this beer is done. I’m going to keg this as soon as I get a chance (likely tomorrow), and call it finished.




In the end, I actually just dropped the keg with the oak cubes straight into the kegerator to carbonate. After two weeks of carbing up, I can tell you this hands down, the best beer I’ve ever made. I’m very proud to call this beer my own, and I ended up bottling off a dozen bottles to set aside for a homebrew vertical in the years to come.


As for the beer left in the keg, the appearance is a little lighter than I first planned, but still a rich black with a tan head. The head actually persists better than I expected for a 12% ABV beer. The aroma is big bourbon notes with rich chocolate behind it. This beer doesn’t have a massive roasty, coffee like aroma, but that’s not necessarily a bad thing. The first thing that surprised me about tasting this was that it isn’t as boozy as I expected it would be. It drinks like a much lower ABV stout, and I can’t help but think the year on the oak helped with that. The flavors that jump out are chocolate and bourbon, followed by a roasted note, and an underlying sweetness. Mouthfeel is medium-full. It’s not overly rich or cloying, and the beer definitely begs another sip after you put the glass down.




Considering hindsight is 20/20, how successful was this little experiment? Quite successful. I’ll admit that I even had a couple happy accidents go my way. I initially planned for this beer to be 12 points higher in gravity, and for it to finish 5-6 points higher. I’m really glad that wasn’t the case. There’s a balance between the alcohol, the booziness, and the dryness (for lack of a better word), that make this beer very drinkable. Often times I find BA Imperial stouts to be absolutely delicious, but hard to get through a glass of. Either a strong booziness, or cloying sweetness keep the beer from being overly drinkable.


With that said, I’m getting very close to brewing the 2017 version of this beer, and there’s still some room for improvement. To start with I’m going to increase the Roasted Barley and Carafa III to 14oz and 12oz respectively. I think an extra half pound of highly-kilned malt should give me that jet black color I’m looking for. It should also give a hint more roasted character without taking things to far. I also plan on adding 1.5oz of bourbon-soaked charred oak cubes right from the start. 2017 will also be the ‘Vanilla Bean’ version, but I’ll save that for a later post.


I’ll wrap up with a few tips for anyone who plans on tackling a beer like this. First, char your oak cubes in advance, and char them well. Like really blast the shit out of them with the propane torch. This is where the heart and soak of the barrel-aged flavor come from. Soak them in bourbon for at least a month. Brew up a beer that will lend it self well to aging, and make damn sure you’re happy with it before you lay it down for awhile. ‘Barrel aging’ is not going to make a shitty beer good, or a good beer great. Be very mindful of oxidation. In the end, after some extensive reading, I decided to avoid purposefully oxidizing the beer at all. I figured 10-12 samples will introduce a marginal amount of O2 into the beer, even while still purging the keg after every sample. A marginal amount of O2 is really all you’re looking for; barrels allow in less O2 than you might think. Also, I was definitely stressed over some of the twists and turns the flavor of this beer took over the aging process. Sometimes the best advice is just to ride it out.


Lastly, make sure to share a beer like this with family and friends. I’m all for setting some special beers aside, but we shared most of this batch with everyone we know over the holidays. Beer is for drinking, not for hoarding. Even those precious, waxed-dipped, barrel-aged, time-sucking, batches. Cheers everyone!

9 thoughts on “2016 Mellow Midnight Update”
  1. Chris Hudson 01.12.2017 on 9:20 AM Reply


    Your experience has inspired me!

    I may have to do my own project!

    What are your plans for the vanilla version? Infuse the bourbon with vanilla and then use that bourbon on the cubes?



    P.S. MORE POSTS!!! 🙂

    • Scott 01.12.2017 on 9:52 AM Reply

      Awesome! For the vanilla version I’ve emailed quite a few breweries that make BA vanilla stouts to see how much they use. Scaled down to the home-brew level it sounds like 2 beans per 5 gallon batch is about right. I’m planning on adding the beans directly to the beer as it’s aging. The only thing I’m still not sure on is how long they need to sit in there. It’s likely not that long.

  2. Oisin 01.12.2017 on 1:08 PM Reply

    Great article as usual and great timing.

    I’m doing a RIS this weekend and would love to age some on oak dominos that I have. Only problem is I don’t have a propane torch or any access to on. Any other methods of charring advised?

    • Scott 01.12.2017 on 10:11 PM Reply

      You’ll need some kind of gas flame to char them enough. Butane or propane torches are usually pretty affordable (at least in the US). Maybe find a friend with one? Charring the oak doesn’t take very long.

    • Gordon 01.13.2017 on 12:09 PM Reply

      Use your kettle burner or gas BBQ

  3. Steve Masar 01.12.2017 on 9:46 PM Reply

    Scott, if I remember right, you charred your original oak cubes on 1-2 sides. Based on your tips above, are you now suggesting to char them as much as possible on all sides?

    • Scott 01.12.2017 on 10:04 PM Reply

      I likely didn’t articulate that as well as I should have. I torched one side of the oak cubes, did my best to flip them all over and torched them again. Due to the size of the flame on a typical propane torch, and the size of the oak cubes, most of the surface gets charred pretty well.

      Only 1-2 sides glowed orange, but the end result is very charred all over.

  4. Paul Taylor 01.13.2017 on 6:30 AM Reply

    Great write up Scott, with regards to Vanilla I would highly recommend soaking them for as long as you can in Vodka to extract and preserve the flavour. I added 3 beans to a stout and left for a few weeks, the flavour was there but faded very quickly to nothing.

  5. David 02.09.2017 on 7:38 AM Reply

    Scott, what is bottling from keg method? I use a rubber stopper with the fill tube pushed through it, then just fill from my tap, breaking the seal on the bottle when it stops filling. While this works ok and doesn’t foam much, I still feel like my carb levels in the bottle are lower than I want.

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