As I noted a little while ago a friend and I decided to go in on a used 15 gallon whiskey barrel. We decided to brew a Rye IPA as our first batch (recipe coming soon) and before any beer can go in the barrel, the barrel itself needs to be cleaned as to not contaminate 15 gallons of beer.
Questions to ask
To begin with I want to quickly look at some things that you might want to consider when picking a whiskey barrel. Below is a small list of things that I would take into account if I were getting a barrel:
- How old is the barrel?
- Was it recently dumped?
- What did it previously hold? Beer, liquor, wine?
- Are there any noticeable cracks, bulges, or anything else that looks out of sorts?
- Is the barrel sealed or is the bung open?
There are many reasons to ask these questions, but the main thing you are looking for is something that will turn out a quality beer. The age of the barrel matters because you want to know the strength of oak and or liquor flavor that you are going to get. A newer or once used barrel will not give as much liquor flavor, but it will give a lot of oak flavor. A recently dumped barrel is important as you don’t want the wood to dry out, thus giving air and the little bugs that come with air a chance to make their home in the wood. Some used barrels will hold things other than liquor. My preference is to not get a barrel that once held beer as there could be yeast in there that you will never truly get out. Make sure that you barrel looks like a barrel for many of the reasons noted above. Finally you want to make sure your barrel is sealed. Ours was sealed with a wooden bung, that needed a hammer and several good whacks to dislodge. This helps ensure that your barrel stays air tight.
There are several options to cleaning your barrel. In this process you are looking to get rid of anything that would contaminate your beer. Remember, a barrel is the same thing as a secondary fermentor. Below I have outlined several options and provided your with the option that we went with and why.
Sanitize like a fermentor
You can put a typical no rinse sanitizer into a barrel like what you would do with a fermentor and let it sit for awhile. This will kill most things on the surface of the barrel and if your leave it sit for long enough, it will absorb into the wood killing things that are deeper. It will not get rid of anything, nor will any of these methods. I considered this for a long time, but decided against it as I didn’t want anything left that would kill any yeast that transferred over. We are looking to bottle this beer after aging so I want to have some yeast alive for carbonating the bottles.
Campden tablets are usually used in wine making. They kill pretty much everything that they come in contact with. For the reasons noted above we did not go this route, but may in the future.
Potassium Metabisulfite Powder
This is the active ingredient in campden tablets and I did not pick it for the same reasons.
I decided to go with hot water. I heated 15 gallons of water up to 170 degrees and then poured it into the barrel with the help of a funnel. I then sealed the barrel up and left it sit there for 30 minutes. I was looking to neutralize anything on the surface and to also check for leaks. The hot water allows the wood to swell quickly, ensuring that any leak would be plugged more quickly. I also knew that we had a good barrel that was sealed well. In addition, the beer going into the barrel is currently at 9.5% ABV, so most critters that would like to ruin our beer wouldn’t be able to survive in that setting.
The beer has been in the barrel for about a week at this point. I’ll give it a few more weeks before I check it and add back any beer that has evaporated out. There are a number of other ways to clean a barrel, but hot water in a well sealed, recently dumped barrel, did the trick for me.