What Is Barrel Aged Coffee?
Rounton Coffee Roasters x Donzoko Brewing Company
It’s not every day you receive an email from your favourite North East brewer (Donzoko Brewing Company) regarding an exciting collaboration. Their enthusiasm for creating and developing flavour-forward, delicious and innovative beers is something to be commended. I should know, I’ve had a fair few!
The email from Reece (founder and master brewer) went something like this:
“Now dude, fancy ageing some coffee in a bourbon barrel so I can brew some up in a batch of beer?”
“Damn right” was the reply (or words to that effect).
It didn’t take me long to realise that this was going to be something of an epic experiment. That said, I didn’t fully expect how amazing the results would be, not just in the beer but as an outstanding coffee. It’s that good that it won’t all be going into the beer – there’s plenty left for you at home (and for us)!
What about the beer?
The plan from Donzoko was simple:
- Get some great specialty coffee
- Get a Bourbon barrel
- Put said coffee in said barrel, and wait.
- Roast barrel-aged coffee
- Use barrel-aged coffee to brew up some delicious beer.
Now obviously it’s not that simple. The work and ingredients that will go into the beer will be revealed in the not too distant future, but for this blog, I want to focus on the coffee.
What about the coffee?
After multiple cupping sessions (both Bourbon and coffee) we finally landed on a coffee from Los Cielitos in Nicaragua. This coffee offered so much caramel sweetness with layers of buttery shortbread and a lingering peach – perfect to complement the smokey vanilla hit from the whiskey. The coffee’s honey process and altitude growth of 1300masl was also a deciding factor.
This meant that the coffee would be slightly more porous, aiding in the absorption of the whiskey residue that was in the barrel. This coffee would be a standout in its own right, so we were super excited for the results.
How does barrel-ageing work?
There are some rules to note when purchasing Bourbon barrels – one of which is to never name the whiskey in any marketing material, so, unfortunately, this will be our little secret. Secondly, Bourbon barrels (unlike wine and other spirits) can only be used once to age the whiskey. This particular whiskey has seen the inside of this barrel for 4 years, so they’ve become very well acquainted! The barrel is made from oak, first scorched on the inside to add those deep smokey tones, then whiskey is added and sealed to mature for 4 years.
The barrel would’ve easily held 100kg of coffee but we decided to only add 1 x 69kg bag of green coffee. The idea behind this was to give the coffee enough room to absorb as much of the whiskey residue as possible, as well as creating enough space for agitation. We did this (or should I say “I did this”) daily by laying the barrel on its side and rolling it 4-5 times around the roastery. The thing was mega heavy, but my feeling was that doing this would aid in the even absorption of the flavours throughout the whole bean pile.
This took place over 2 weeks, as from lots of reading, this seemed to be the optimum time needed for the beans to take on the flavours and aromas that the barrel had to offer. The last note on this would be to find a reputable barrel supplier. The reason for this is that you want the freshest barrels with hopefully a little whiskey left inside. Let’s just say we were not disappointed….
How did we roast it?
Being the first time, we approached this roast slightly different to our normal profiles. Understanding that the coffee would have a higher moisture content coming out the barrel we wanted to give the coffee a little extra time to dry out at the start of the roast. The start of roast or the drying phase as it is also known is a crucial time for any roast.
This phase will provide the beans with the energy needed to meet the specific parameters of each roast. Too much heat, and the roast will get away from you, not leaving enough room for sufficient development. Too little, and the roast can become muted and baked. So, we approached with some caution as we needed the right amount of drying time, without sacrificing any of the coffee’s natural sweetness and acidity.
We opted for a charge temperature of 20 degrees centigrade higher than we would if we were roasting this coffee in our usual way. We then opted for a soak of around 2 minutes. A soak is when you reduce the heat applied to a minimum, so the beans are just soaking up the heat from the preheated drum as supposed to applying direct heat from the burners. This allowed us enough time for a nice gentle drying phase but with still enough temperature so we could hit our desired end time and temperature.
The rest of the roast was completed within our desired timeframe of 8-10 minutes with a final temperature of around 210 degrees centigrade, coaxing out more of the caramel sweetness this coffee had to offer from the cupping table.
How does it taste?
Now I have to be honest, the smell of this coffee is truly mind-blowing. Rich in caramel and vanilla with a huge hit of bourbon on the aroma. This will probably not be your morning coffee but will truly go down a treat as a decedent after-dinner brew accompanied by your favourite dessert. The taste of this coffee is something to be savoured with a big hit of vanilla and the sweetness from the coffee taking centre stage and with just the right amount of subtle bourbon character lingering on the finish.
I will also be dusting off the cocktail shaker again this year and trying this coffee out in my updated espresso martini cocktail. I am also looking forward to trying out the beer and would like to thank Reece again for letting us get involved in this amazing experiment. Here’s to many collaborations in the future. We hope you enjoy the coffee and would love you to get in touch with your feedback.