I have a few glass carboys that I use to age sours or other mixed fermentation beers long-term (6-18 months). In the past, I had used a standard airlock with a drilled rubber stopper. Last year, I wasn’t checking on them regularly, and one of the airlocks went dry. By the time that I noticed, the beer had developed a vinegary taste and had to be dumped.
In response, I started replacing the airlock and drilled rubber stopper with a solid rubber stopper after fermentation stopped. This solved the airlock issue, but as temperatures went up, I began to worry that increasing temperatures would force out the stoppers. (The carboys are in a room in the basement. The temperature does not swing wildly, but there are seasonal effects.) Last week, I “burped” each of the carboys by temporarily removing the stoppers, and a decent amount of pressure had built up in each one.
I saw these breathable silicone bungs on MoreBeer: Breathable Bung for Glass Carboys | CellarScience® | MoreBeer
This would seem to solve the immediate problems – there’s no airlock to go dry and it would not allow pressure to build up. But I know that silicone is pretty oxygen permeable, and I’m generally very wary of cold-side oxygen exposure. On the other hand, the beers that I’m keeping in the carboys are traditionally barrel-aged, so might not be negatively affected by the oxygen permeability.
Another, more expensive and space-consuming option, would be to buy additional kegs and in age in keg once fermentation stops.
I can also continue on with the rubber stoppers and either (a) check airlocks more religiously or (b) release pressure from the solid stopper whenever the temperature increases. But I prefer a solution that is failproof.
Any thoughts? How do people generally age these beers for a long period of time?
Thanks
In response, I started replacing the airlock and drilled rubber stopper with a solid rubber stopper after fermentation stopped. This solved the airlock issue, but as temperatures went up, I began to worry that increasing temperatures would force out the stoppers. (The carboys are in a room in the basement. The temperature does not swing wildly, but there are seasonal effects.) Last week, I “burped” each of the carboys by temporarily removing the stoppers, and a decent amount of pressure had built up in each one.
I saw these breathable silicone bungs on MoreBeer: Breathable Bung for Glass Carboys | CellarScience® | MoreBeer
This would seem to solve the immediate problems – there’s no airlock to go dry and it would not allow pressure to build up. But I know that silicone is pretty oxygen permeable, and I’m generally very wary of cold-side oxygen exposure. On the other hand, the beers that I’m keeping in the carboys are traditionally barrel-aged, so might not be negatively affected by the oxygen permeability.
Another, more expensive and space-consuming option, would be to buy additional kegs and in age in keg once fermentation stops.
I can also continue on with the rubber stoppers and either (a) check airlocks more religiously or (b) release pressure from the solid stopper whenever the temperature increases. But I prefer a solution that is failproof.
Any thoughts? How do people generally age these beers for a long period of time?
Thanks