Venting Overcarbonated Flip-Top Bottles

[russell_c_cook]

Hi everyone,

Due to some bungling on Wednesday evening, we bottled our pale ale with about 3 times the amount of priming sugar we should have.

What I have done is vent the bottles after 12,24 and 36 hours. I plan to keep doing this every 12 hours. I have been covering my body with thick clothing, wearing gloves and safety goggles in case of explosion,
and a thick towel is beteeen me and the bottle as I open them.

My idea is that this will avoid pressure building up too much, and also that oxidisation is not a big issue as, when I vent, escaping CO2 will prevent oxygen coming in.

I'd like to hear people's intuitions about how long would be good to keep doing the 12 hour vents? Just hypothetically speaking, I may just chuck the batch to be safe. I'm not so interested in putting it back into the fermenter.

So far the vents have been similar in intensity to opening a properly carbonated beer.

Any ideas would be great.

 

[TwoCrows]

Cube it and then drink it in a big session!!

 

[Lyrebird_Cycles]

This is a real how long is a piece of string question but as an example: if your headspace is say 5% of your container volume and the beer averages to about 2 x desired [CO2] over the period concerned and reached equilibrium before each venting, on average you will reduce the [CO2] by something around 0.15 g/l every time you vent. Assuming you need to reduce your [CO2] by say 8 g/l, if you vent twice a day it will take a little over three weeks.

Unfortunately if the headspace pressure reaches equilibrium the bottle will likely fail so it would probably be a good idea to increase the venting frequency.

The [CO2] reaches the maximal value at about 4 days for normal levels of priming, in your case it will take longer but I would still expect it to hit max value within a week.

 

[russell_c_cook]

Two Crows,
Thanks for getting in touch, what does "cube it" mean?

Lyrebird Cycles,

Thanks for the ballpark figure, it will give me a starting point. My headspace is actually more like 10%, so I'll factor that in.

I'll post results once I have them.

 

[russell_c_cook]

It's been almost 5 days now, and I have been venting 2 or 3 times a day. Gas has been escaping but nothing dramatic at all, just like opening a bottle of normal beer.

The smell of the escaping gas has become less yeasty, it seems to me, and the bottles appear to have a yeast cake forming at the bottom.

Any thoughts welcome.

P.S. The temperature has been a steady 19-20 degrees.

 

[rossbaker]

This would scare the crap out of me, but good effort. Maybe select 1 or 2 bottles that you always open first and as soon as you feel their pressure drop when venting leave the whole batch for a couple of days and use a different two to test first.

 

[rossbaker]

Another thought... you could use glad wrap and rubber bands to turn each bottle into a mini fermenter. Allow each bottle to ferment out safely then re-prime with carb drops or sugar cubes to the correct dose and re-send. Might be a bit fiddly, but better than venting every 12 hours for 3 weeks, and certainly better than stitches from exploding glass.

 

[russell_c_cook]

Hi Ross,

Thanks for the feedback.

It's been over a week now, and I vented up until the 5th day, now I'm gonna just leave it to play out as it may. Next time I would do it the way you described. I've wrapped the bottles in towels to hopefully absorb any possible damage.

As a note, it seems that the bottles may be self-venting to some extent, as the fermenting fridge has a beery smell when I open the door.

Since they did have carbonation when I vented them, perhaps when the pressure reaches a certain point, the rubber seals are forced slightly open. As the pressure then drops they close up again.

Anyhow, in a few more days I'll chill one bottle to 4 degrees for a few days, have a try and report back.

 

[PolyVinalDistillate]

Hmm.. 2017... I worry this experiment didn't go well