I’m often asked about the wooden barrels I use in my homebrewery. While people are mainly interested in their size, the following questions tend more towards what to do once you get a barrel, how long to age in a barrel, and what to do once you’re done using a barrel. This post is not meant to serve as a catch-all guide, moreso what I have found to work well over for me the last five years I’ve been using barrels. I currently have five 50-60 gallon barrels. Three are American Oak whiskey barrels, and two are French Oak barrels that held Riesling wine for ten years prior to me getting them. While I used to have a few more, I found five is a good number (for now!)
Disclaimer: I’ve never used a barrel smaller than fifty gallons, so I can’t say that all of these methods will fit each and every barrel one might run across in a homebrewing adventure. However, most of these methods will work across the size spectrum.
What do you do when you get a barrel?
When I know I’m going to be getting a barrel, I try to have beer ready to put into it. If I’m using the barrel as a primary fermentor as well as aging vessel, I align a brewday for within a few days of getting the barrel. Many people freak out (or so I’ve read) and think they have to fill their barrel with a holding solution if they aren’t going to be filling it immediately. My advice is DON’T DO IT!
First, odds are the barrel you just received was not emptied hours ago. Its probably been sitting in a warehouse for days, if not weeks – its hard to tell. A few more days probably won’t hurt anything.
Secondly, you want to leave as much flavor in the barrel as you can. You probably won’t get a chance to use a ‘fresh’ barrel (fresh meaning the last thing in it was spirits/wine) as often as you’d like, so use that flavor for something wonderful! [Rumor has it when Allagash Brewing first started getting their barrels, they would rinse them out and clean them prior to use. After immediately seeing the tan liquid flowing down the drain, they realized the flavor potential they were missing out on and promptly changed methods.]
So, what should you do? Fill it! Figure out a style that will go best with the type of barrel and its previous contents. Try to maximize that flavor contribution. If you’re sitting on the edge of your seat thinking about sour beer (as I am often), don’t worry – you can do that after you’re done aging this first beer (unless you want big wine/spirit flavors in your sour beer. I’ve done both with great results.)
More often than not, I run a clean beer through the barrel first and then follow up with a sour beer afterwards.
How long should I leave the beer in the barrel?
This mainly boils down to personal preference and taste. I have a small nail in each the side of all my barrels and taste them every couple weeks (although the sour beers not as often.)
An important consideration for smaller barrel users would be that you have a much larger surface area to volume ratio. Approximating a barrel stave as a circular arc, and subtracting for the thickness of the staves/endcaps (which I approximated at 1″), we can use some calculus to rotate the stave about the x-axis of an imaginary barrel located at the origin.
A barrel with a volume of 58.5 gallons has a surface area of approximately 2997 square inches. A barrel with a volume of 10.2 gallons has a surface area of 983 sq in. Therefore, the smaller barrel has a SA:V ratio of 95 and the larger barrel 51. What does this mean for a homebrewer? If you hear about your favorite brewery getting some great flavor from aging their barleywine in a whiskey barrel for a year, you might want to think about 5-6 months for your own project. However, as awesome as all that math is, taste should ultimately decide.
I put a permanent page on the website for these calculations, you can find it here.
For my barrels, I go strictly by taste for a clean beer in a fresh barrel. When fermenting a sour beer, taste still dominates but I give the beer at least a year in the barrel, if not two before I consider packaging. When it comes to clean beers, I previously aged during the secondary fermentation; but I am currently fermenting a Belgian quad in a whiskey barrel for its primary.
That beer is delicious, what do I do now?
When it comes time to package, you must still take into consideration everything you would if you were packaging a beer from a carboy. Spray the top of the barrel with sanitizer. Rack into a bottling bucket or directly into a keg. Finish as necessary.
In all honesty, once I get my barrels I keep them full 99% of the time. I have only done a “holding solution” once and I hated it. It was a ton of water, chemicals, and all around a pain in the ass. Granted, on a smaller scale it might be less of a pain, but I hold to my point. Barrels were made to be filled. Just like when I find out I’m getting a barrel, I plan a brew day for the day after I package my previous beer. A great way to do it is empty/package one night, then brew/fill the next day.
For smaller barrels, a siphon works fine. In fact, for large barrels it works well too. I’ve graduated to the point where I now package my barrels into 15.5 sanke kegs, so there is a lot less cleaning to be done. Barrels are emptied using a March pump and some 1/2 high temp tubing. The tubing is flexible enough I can lay it on the bottom of the barrel and after the initial plug of trub the rest of the beer comes out quite clear.
After packaging, I take the barrel and put it upside down over a drain or a bucket to get the yeast and sediment out. I use a multi-directional sprayer (just like you’d use in a carboy) and spray (with the bung facing down) until water runs clear. Temperature doesn’t matter to me, but I generally do use warm water.
Once the water runs clear, I put the barrel on its side and add more water. If you’re using a small barrel, just hold it under your sink. Then I slosh the barrel around every which way to make sure the whole thing is rinsed. A visual check with a flashlight confirms the barrel is clean. If it isn’t, I’ll put in a length of chain and roll that around to “scrub” out any nooks and crannies.
And… that’s it. The barrel gets one final rinse, and I fill it up with beer.
A few other thoughts…
If you do let your barrel go dry, fill it up with hot water. It will leak, so keep it somewhere that it won’t matter. Keep topping it off until the leaking stops. If the leaking persists for more than a day or two, you might need to look into sealing issues. There are food grade epoxies out there – that’s what I would use if I had an issue.
If you decide to keep your barrel full (to keep it swollen) you will need to use a holding solution of citric acid and potassium metabisulfite in a 1:2 ratio. For me that’s a half pound of citric acid and a pound of K2SO4 (50 gallons.) Once I filled a barrel with plain water and left it thinking “I’d get to it” … and it molded. It is now cribbage boards, office toys, and pens.
When you do get a barrel, if its a big one ask some friends to help you move it. Nothing is worse than a chunk missing from your barrel, or your back. These things can get heavy. I’ve had my share of issues when moving them around (even a full one once) and I’ve found that friends are more than happy to help for some barrel aged beer. If you don’t have friends, a hand truck and ratcheting strap can work as well.
It isn’t required to have a barrel to age with wood. If you go the non-barrel route, let me suggest to you cubes rather than chips. Surface area calculations will differ also, as you’re now dealing with different grain directions and wood freshness.