8 replies to this topic

[John Flanagan]

I have two 15 gallon barrels that have been stored dry for a little over a year at 55F and 60-70% humidity. I noticed a while back that areas on the seems between the staves were starting to turn black. I pulled the barrels out of storage today and the problem has gotten worse: the black stain is present on most of the seems and spans 50% of the seem stretching about 2" on either side. I assume this is mold. I scrubbed the black areas with a strong sulfite solution and a stiff brissel brush, but nothing really came off. The inside of the barrels smell fine. I plan on using these barrels soon to blend and store wine for a short period prior to bottling.

So, my questions are:

Should I worry about the exterior mold since the inside of the barrel smells fine?
Any suggestions for ways to clean/kill the mold other than sulfite solution and a brush?
How do I keep this from happening in the future?

Thanks for the help.

[Hammered]

I would use percarbonate (oxyclean) to thoroughly clean them then sanitize them well with a 1000 ppm sulfite solution (scrub brush).

[rpage53]

You should always acidify your sulfite with citric or tartaric acid, its much more effective that way. The risk is that the staves have shrunk and the mildew is growing between the staves where you can't clean it and it could taint the wine. You can't be sure that its clean without risking a batch of wine and you don't know what else is growing that you can't see.

There's always a risk storing a wine barrel dry that it will become unuseable. The only sure solution that I know of, is to store them frozen.

Rick.

[Hammered]

I've noticed small black dots or spots on the edges of wine barrels gotten from wineries that I've broken down for one reason or another. Seems fairly common.

Rick's 100% correct on adding citric or tartaric to bring the pH down on any equipment SO2 sanitizing solution.

[Tomer1]

Maybe try a strong hydrogen peroxide sluion if So2 solution doesnt work. That should kill any surface mold.

[NorthernWiner]

How do I keep this from happening in the future?

I'm not sure what would be most effective for removing existing mold. To be honest, I've never run across this. If it were anywhere else in my house, I would use a bleach solution, but that's probably the last thing you'd want to apply to a wine barrel.

As far as how to prevent it, I've used this mildewcide product on my barrels with good results. It also keeps the barrel looking new by preventing wine stains from setting permanently on the surface.
https://www.piwine.c...&category_id=81

[DesertDance]

Peroxide won't hurt you, so I'd probably go with that. In my youth, I went with a church group to some countries where conditions weren't that sanitary, and we always put a small amount of bleach in our drinking water. They both kill mold and sanitize! Nice to know these things can happen.
Suzi

[rpage53]

Mildew will stain the wood black, so even after the mould is removed the black remains. Peroxide (which is also the active ingredient in percarbonate/oxiclean) will bleach out the stain but you may need to mix the powdered percarbonate with a little water into a paste and scrub the wood to completely bleach the stain.
Mildewed wood is a common problem with leaky condos.
http://www.hytechsales.com/mildew.html

Rick.

[John Flanagan]

Thanks for the tips. Sounds like percarbonate scrub would help on top of the strong sulfur solution I already used. I have another barrel purchased at the same time as one of the ones with the mold, and that one hasn't had any issues. It's a different cooper though, and has spent more time filled. I'll definitely be coating my newer barrels with mildewcide.