Strange bubbling activity - Temperature change or Dry Hop!

[wafublue]

Hi everyone - new to home-brewing but really excited for the first taste of my first batch. Looking for advice if anyone has seen this before: essentially I started primary fermentation of an IPA in the garage as it was a steady 18-22 degrees C (65-72F) in a spell of good weather. 7 days into a two week fermentation we had a cold night and my bubbling ceased completely. Fearing the worst I took it into the house and half a day later it started bubbling again every 3 secs. Patted myself on the back for the recovery. 2 days later it stopped completely. Devastated at the prospect of ruining the beer I took a sample of 1017 (start 1048 - final est 1005) - and thought I would throw the Hops in now in case the process was ruined but in case i could salvage something drinkable. Problem is, now it's still bubbling like crazy approx 1.5 per sec 24 hours later. Is this because the temperature kickstarted the process back up again (intermittently) or can the dry hopping cause such vigorous bubbling??? If it's the former i'm concerned the fermentation is back on track but i've dry-hopped way too early... Sorry for the long post - appreciate any advice!

 

[CU_tony]

Bubbling just means you have a higher pressure inside the carboy and is not indicative of fermentation by itself.
If you warm the wort it will expand slightly and vent, also a higher temp may restart fermentation if it stalled from the cold night.
Also I have noticed that dry hopping may invigorate airlock activity.
No worries on the brew though, it sounds like its doing well.
Until you sample the same gravity a few days apart it's not likely to be done just yet.

 

[CU_tony]

And don't worry about dry hopping too early, as long as the bulk of fermentation is done you'll be fine. I even dry hopped a beer when I pitched once and it was tasty after conditioning for a few weeks!

 

[brewkinger]

The bubbling is more than likely because of the temperature change.
The addition of dry hops could make it off gas some more I think too.
No harm done at this point, the only possible down side is with active bubbling you could potentially lose some of your aroma from the hops.

I still wouldn't worry about it though. It will still be beer in the end.

 

[TasunkaWitko]

Bubbling just means you have a higher pressure inside the carboy and is not indicative of fermentation by itself.
If you warm the wort it will expand slightly and vent....

This answers a question that I was just about to ask on this forum.... Thank you!

 

[wafublue]

Thanks very much for the quick replies - very useful, and a much better prognosis than I originally feared...!!!

 

[jddevinn]

The colder the beer is the more CO2 will dissolve into solution at a steady pressure. As active fermentation is occurring CO2 is produced and held in suspension. When the temperature rises, even if fermentation is done, the beer will no longer have the "ability" to hold as much CO2 in suspension and it will off-gas the CO2 until it reaches equilibrium. Agitating the fermenter will cause it to do this quicker.