If you've been spending too much time in bars lately — and we certainly hope you have been — you've likely noticed the rise of barrel-aged cocktails. The technique takes some of your favourite mixed drinks, mellows them out and adds some layers of complexity. There is, however, a barrier to entry for most at-home barkeeps: Patience. Unless you know this shortcut.
Barrel-aging typically takes six weeks. Depending on what you're making and what kind of barrel you have, it could be months. Of course, the best things come to those who wait, but for those who want to try a barrel-aged cocktail right now, we've got a trick for you.
It's time for Happy Hour, Gizmodo's weekend booze column. A cocktail shaker full of innovation, science and alcohol. Let's reverse Benjamin Button some booze!
This comes to us from our friend Timothy Zohn, at the AQ Bar in San Francisco, who last week taught us how to clarify citrous juices to make clear cocktails. All you need is an iSi cream whipper, some pieces of oak, a shaker, a strainer and a little bit of fire. Oh, and the ingredients for the cocktail of your choice.
You may remember the iSi from our piece on creating rapid infusions. That is, essentially, what we're doing here, except instead of infusing a single spirit, we're infusing a pre-mixed cocktail, and instead of fresh botanicals, we're using burnt wood. The mechanisms remain the same, though. The high pressure forces the liquid into the cell membranes of the wood. Once the pressure is released, the liquid escapes from the wood, dragging the flavours along with it.
Here's how to do it:
- Step 1: Char some wood. Since oak is what most ageing barrels are made of, that's what we recommend you start with. You can find oak chips at most places where they sell barbecue supplies. All you really need to do is light them on fire, and then put them out before they burn too much. Tim tossed them into a metal pan and used a butane torch to set them ablaze, then smothered them out by laying a damp towel over the pan. Or you could set them on fire in a grill or fireplace.
- Step 2: Pick the Right Pieces. Unless you are a zen fire master, the pieces aren't all going to char evenly. That's OK. You want to select a small handful of pieces that are medium-burned. You want plenty of exposed wood, too. This may take some trial and error. Once you're happy with your chosen pieces, toss them into your iSi container.
- Note: If you are able to get your hands on a stave from an actual barrel, that's even better, especially if it was already used for bourbon or wine (it'll add some nice flavours). If that's the case, you can skip steps one and two, and instead, saw off a piece of the stave that will fit into the iSi charger.
- Step 3: Make your cocktail of choice and pour it in to the iSi. This probably goes without saying, but don't add ice yet. The dilution comes after you instant-barrel-age it, because alcohol is a much more efficient means of extracting flavour compared to water. Manhattans and Negronis are probably the two most popular cocktails for barrel-ageing right now, but Tim decided to go with an Alaska Cocktail (made famous in the Savoy Cocktail Book). That's three parts dry gin (he used Beefeater 24), one part yellow Chartreuse, and a dash or two of orange bitters (optional). They're delicious, but be careful — they're a lot stronger than they taste.
- Step 4: Rapid Infusion. Screw the top of the iSi down nice and tight, and then spike it with a nitrous oxide cartridge (make sure you're using N2O, not CO2). Let it rest a minute, then charge it with another N2O cartridge. Now gently agitate it for a minute or so. You don't need to whip it like a cocktail shaker, just get everything moving. Let it rest for another minute or two.
- Step 5: Release the Krakken. Put a towel over the iSi's nozzle and, keeping it vertical, slowly pull the trigger to gently release the gas. The towel is there in case any liquid escapes. Once the pressure is released, unscrew the lid all the way and pour the drink through a strainer into your awaiting shaker. Add ice, and stir to sufficiently chill and dilute the drink (Alaskas, Manhattans and Negronis are all best stirred, not shaken. Same with Martinis, Mr Bond). Strain the drink into your cocktail glass and enjoy!
As you can see in the video above, the process darkens the drink and does indeed make it look older. Whiskey comes out of the distilling process clear (it's known as "white dog" at that stage). It doesn't take on its dark colour until it ages in a barrel.
Tasting the drink before and after really was two very different experiences. Before undergoing the process, the Alaska was very crisp and the sweetness really stood out. Afterward, the smokey wood flavours made it taste more settled. It had more going on. Both were great in their own right — they're just different.
So, this isn't really barrel-ageing. The real barrel-ageing of a cocktail essentially does two things:
- 1: Adds New flavours. It adds the flavour of the wooden (ideally charred) barrel to the drink. This gives it the a flavour we associate with aged spirits, like bourbon, which spends a minimum of three years in a barrel, or Scotch whisky, which is frequently aged much longer.
- 2: Gives Real Age. The considerable time spent resting allows the flavours of the disparate ingredients to blend. When you make, say, a Negroni, you have the flavours of three distinct ingredients: the gin, the Campari, and the vermouth. When it's fresh, you can taste each of those elements a little more distinctly. Once the drink has spent six weeks or so in a barrel however, there is a more unified flavour. There is also a certain hard-to-quantify "mellowing" of the drink, and it's not just the wood, because a similar effect is achieve through bottle-ageing cocktails. This isn't just geekery for geekery's sake; the drink goes down incredibly smoothly.
So, while no one could argue that this instant barrel-ageing technique does an excellent job of adding the wood flavours, the passage of time is something that's bound to spark some debate. The process is actually very similar to what Tom Lix is doing with his Cleveland Whisky, which we wrote about earlier this week. He's essentially trying to use pressure to accelerate the agine process. As he describes it:
The spirit ages in a whiskey barrel like normal for the first six months of its life. Then it is deposited in stainless steel tanks. Meanwhile, the barrel it aged in is cut up, processed and put into the tank as well. Within the tank, the spirit is agitated, and undergoes a series of differences in pressure to squeeze in and out of the wood pores.
Sounds familiar, no? The whiskey spends just a week in those pressurised tanks, where as a true bourbon would have to spend at least another 2.5 years in the wood barrel.
We only had the chance to sample one of these rapidly aged cocktails, so we can't deliver a definitive verdict, but it seemed to us that the high pressure we used helped the flavours bind together, but it didn't quite achieve that same mellowing effect that perhaps only age can provide. More experimentation is certainly required.
That said, this is at least a pretty good approximation of the real thing. It's certainly a terrific way to experiment with the flavours of barrel ageing in different cocktails, and it even has some advantages to real barrel ageing. You could experiment with different types of wood, including some that might not be used in commercially available barrels (make sure it's non-toxic, though). And of course the biggest advantage it has over real barrel ageing, is that it only takes about 1/12,000th as long. Leaves you more time for drinking.
Timothy Zohn is the Bar Manager at AQ Restaurant in San Francisco, He has spent the last eight years working at some of the best bars in the city with some of the best bartenders in the country. He is proud to call San Francisco home. You can find him on Twitter @TimothyZohn
Thank you to Tim and the AQ Bar and Restaurant for their time, and to Trevor Easter for the love connection.