Aging sours using cork bung for O2 permeability

[scone]

Apologies if this has been discussed before, I couldn't find anything.

I know people use oak dowels through the necks of better bottles and glass carboys for a bit of oxygen permeability (and for the oak aging bit as well of course) for long term aging of sour beers. I was wondering if anyone has tried using a cork bung instead of a rubber stopper to accomplish the same thing.... Obviously the length and density of the cork would have a huge impact on the oxygen permeability. I was thinking about this as an alternate strategy to the oak dowel. I could simply throw an ounce of oak cubes in the secondary, and seal it with a cork stopper/airlock. No chance of cracking the neck or getting beer pushed through the dowel and growing mold. Anyone have thoughts on this? What length of cork stopper would be appropriate?

edit:

 

[Nateo]

Have you seen this article? There is a lot of info on O2 permeability and aging of sour beers

http://www2.parc.com/emdl/members/apte/flemishredale.shtml

 

[scone]

Have you seen this article? There is a lot of info on O2 permeability and aging of sour beers

http://www2.parc.com/emdl/members/apte/flemishredale.shtml

Yep, in fact Raj Apte is the originator of the bung-through-the-neck technique. I haven't seen measurements for cork stopper oxygen permeability though.

 

[Nateo]

I haven't heard of or seen any info on cork stopper lengths, but I bet you could reason it out. I don't think are any analogs in beer, but wine makers know a lot about corks and permeability. Wine corks vary from 1-1/2" to 2". From what I've read, there isn't any real difference in O2 permeability based on length. You could safely rule out length from the variables.

Corks are rated to 7 different grades based on O2 permeability. The more expensive the cork, the lower the O2 permeability. From "best" to "worst": Flor, Extra, Superior, 1st, 2nd, 3rd, 4th agglomerated, and colmated. All champagne corks are 4th grade agglomerated, because they're bigger than most corks and the cost to make a big cork to a high grade is prohibitive.

Realistically, for a cork of any reasonable size for stopping a carboy, you're going to be in the 4th agglomerated or colmated category. Colmated corks are good for wines intended to be drunk young, within 1-2 years.

So if I were aging the beer for 2-4 years I would use a 4th agglomerated cork of any length, or if I were aging for <2 years, a colmated cork of any length

 

[larrynoz]

Apologies if this has been discussed before, I couldn't find anything.

I know people use oak dowels through the necks of better bottles and glass carboys for a bit of oxygen permeability (and for the oak aging bit as well of course) for long term aging of sour beers. I was wondering if anyone has tried using a cock bung instead of a rubber stopper to accomplish the same thing.... Obviously the length and density of the cork would have a huge impact on the oxygen permeability. I was thinking about this as an alternate strategy to the oak dowel. I could simply throw an ounce of oak cubes in the secondary, and seal it with a cork stopper/airlock. No chance of cracking the neck or getting beer pushed through the dowel and growing mold. Anyone have thoughts on this? What length of cork stopper would be appropriate?

Hehehe cock bung hhehehee

 

[Almighty]

The main part of the oak dowel was that the oak dowel was in the liquid so the oxygen could permeate the pellicle. See when you have beer in a barrel it is in contact with the wood where oxygen can permeate a large surface area. I'm not sure how helpful a permeable stopper would be since you are only filling the headspace. And most silicon stoppers are already pretty permeable so not sure if it would be an improvement.

But maybe a cheaper alternative to a stopper and airlock (which are a pain to remember to keep filled over the course of a year)

 

[Nateo]

The main part of the oak dowel was that the oak dowel was in the liquid so the oxygen could permeate the pellicle. See when you have beer in a barrel it is in contact with the wood where oxygen can permeate a large surface area.

The issue is the ratio of volume-to-surface-area. You actually have a lot smaller ratio in a barrel, since the volume of the barrel is so much larger. But you're right about the silicon stopper being permeable enough. They do make stoppers without ports for airlocks if you don't want to fill up the airlock over time.

Tank O2 cc/L.year
Burgundy barrel 8.5
Rodenbach tank, 0.86
Rodenbach tank, 0.53
HDPE bucket 220
Homebrew barrel 23
Glass carboy, 30cm vinyl immersion tube 0.31
Glass carboy, silicone stopper 17
Glass carboy, wood stopper 0.10

 

[scone]

Hehehe cock bung hhehehee

(All for the sake of the perfect oxygen permeability....)

Oh my. Fixed.

 

[scone]

I haven't heard of or seen any info on cork stopper lengths, but I bet you could reason it out. I don't think are any analogs in beer, but wine makers know a lot about corks and permeability. Wine corks vary from 1-1/2" to 2". From what I've read, there isn't any real difference in O2 permeability based on length. You could safely rule out length from the variables.

Corks are rated to 7 different grades based on O2 permeability. The more expensive the cork, the lower the O2 permeability. From "best" to "worst": Flor, Extra, Superior, 1st, 2nd, 3rd, 4th agglomerated, and colmated. All champagne corks are 4th grade agglomerated, because they're bigger than most corks and the cost to make a big cork to a high grade is prohibitive.

Realistically, for a cork of any reasonable size for stopping a carboy, you're going to be in the 4th agglomerated or colmated category. Colmated corks are good for wines intended to be drunk young, within 1-2 years.

So if I were aging the beer for 2-4 years I would use a 4th agglomerated cork of any length, or if I were aging for <2 years, a colmated cork of any length

Awesome info. Thanks!

The main part of the
oak dowel was that the oak dowel was in the liquid so the oxygen could permeate the pellicle. See when you have beer in a barrel it is in contact with the wood where oxygen can permeate a large surface area. I'm not sure how helpful a permeable stopper would be since you are only filling the headspace. And most silicon stoppers are already pretty permeable so not sure if it would be an improvement.

But maybe a cheaper alternative to a stopper and airlock (which are a pain to remember to keep filled over the course of a year)

Yeah actually that's a good point. Barrels allow oxygen to (very) slowly diffuse in from all sides, thus a pellicle on top can't prevent some getting in to the beer. This would certainly not be the case for a carboy. Now you've got me wondering about the oxygen permeability of the pellicle. I would think it can't possibly be a completely impermeable barrier. I don't know this for a fact, but I would think that if you left the top of the carboy completely open allowing for the free exchange of air, the been would turn to vinegar pretty fast despite the pellicle no?

 

[Almighty]

For sure, I didn't mean to imply that the pellicle is a super Oxygen force field. And I have had a sour beer where I only had 1/2 gal in a 1 gal container and with that much headspace it was more acetic than I would have liked.

I usually try to control the amount of oxygen by only tasting my sours every 3 months.

I believe it was Old Sock who confirmed that his barrel aged beers come out more complex than his carboy aged beers. Hopefully I'll have the space soon.

 

[nofootbreak]

Awesome info. Thanks!




Yeah actually that's a good point. Barrels allow oxygen to (very) slowly diffuse in from all sides, thus a pellicle on top can't prevent some getting in to the beer. This would certainly not be the case for a carboy. Now you've got me wondering about the oxygen permeability of the pellicle. I would think it can't possibly be a completely impermeable barrier. I don't know this for a fact, but I would think that if you left the top of the carboy completely open allowing for the free exchange of air, the been would turn to vinegar pretty fast despite the pellicle no?

I listened to a brewers network podcast with Vinnie from Russian River not long ago, and he suggested homebrewers use buckets for the closest oxygen permeability compared to barrels. I wouldnt really want to tie up a carboy for a minimum of a year either.