Acetone in an wood aged beer, how to avoid?

[sablesurfer]

I am drinking a beer from a local micro. It is a decent aged beer, but there is a mild hint of nail polish to it. This one can drink, but in the past I have tried some beer from a team brew and it was ALL nail polish remover. At the time I put it down to temps the barrel was stored in.

Now, on the other hand we have amazing barrel aged beers out there, and it was the only way to age way back 'in the day'. So ethyl acetate isn't a given when barrel aging.

What is it that can be done to prevent this? Is there a technique issue here or just a bad luck issue? How does Firestone walker never have this, but home brewers tend to?

 

[dmtaylor]

I wish I knew the answer to this too. The one and only time I have oaked a beer, I got acetone as well. If I ever oak again, I was planning on removing a small portion of the batch, maybe 10-20%, and oaking that perhaps in two different vessels. Then I can blend these smaller oaked portions back into the main batch according to taste, and rather than ruining the entire batch, if one little oaked sub-batch tastes good and the other goes bad, it won't all be ruined and all a waste of time. Also I plan to soak the wood in vodka or whiskey ahead of time to try to kill whatever is in it. Last time I only boiled the wood chips for a couple of minutes and that wasn't good enough to kill whatever was in them. A good soak in spirits should do the trick.

I'll track this thread to see what other good ideas people come up with.

 

[IJesusChrist]

Some things;
1. Are you sure there is no infection? This smell can come from aceto bacteria, or others.
2. Did you ferment at an appropriate temperature?
3. Did you store in the barrel at a high temperature, and how much trub/yeast transferred to the barrel?

Nail polish is not always acetone, it can be ethyl acetate as well. Make sure you know the difference. Ethyl acetate smells stronger (and better imo).

Without knowing anything more I would say this is caused from higher temperature fermentation, autolysis, and/or stressed yeast in the barrel.

To my knowledge, I don't know why a barrel would tend to produce acetone/ethylacetate over any other container.

 

[InLimbo]

iJesus hit the nail on the head. I think it's less about the barrel, and more about the primary fermentation conditions. You really want to stay in the low range for the yeast strain when you're fermenting a high abv beer. Then give it plenty of time to keg/bottle condition afterwards.

 

[sablesurfer]

So then why do none of the other beers from this place have acetone? That is the thing, it is only the barrel aged stuff. The team brew stuff, that guy always has good stuff on tap, so not like he's a new brewer.

 

[IJesusChrist]

So then why do none of the other beers from this place have acetone? That is the thing, it is only the barrel aged stuff. The team brew stuff, that guy always has good stuff on tap, so not like he's a new brewer.

I can only imagine he or she keeps the keg relatively warm, and relatively quickly so there is still some active fermentation.

Again, I don't know of any instance where acetone/ethylacetate would be barrel specific.

 

[TheBigLebrewsk1]

My distiller friend has said to me once that when distilling the first running a have a sweet nail polish smell and a slightly cloudy look. This is discarded because it is primarily methanol. Methanol has a lower flash point than ethanol. Applying this logic I would boil my oak , I tend to do this for sterilization, prior to use.