Airlock activity w/o fermentation

[Fenster]

I brewed an alt on Oct 7, OG 1.062.
FG 1.023 on Oct 20 and 21.

Transfered to secondary and got another cake on the bottom of the carboy.
Today I go to dry hop and notice some slow activity in the airlock.

If fermentation is complete, what are the bubbles?

 

[Warped04]

When did you transfer?

 

[Fenster]

Transfered on the 21st

 

[Benny Blanco]

"Most brewers will notice a brief increase in activity after racking, but then all activity may cease. This is very normal, it is not additional primary fermentation per se, but just dissolved carbon dioxide coming out of solution due to the disturbance."

 

[Fenster]

Thanks Benny, I can buy that explanation.

 

[david_42]

Also, the fermentation may actually be continuing at a very low rate. It is at 63% attenuation, which is a bit on the low side.

 

[malkore]

airlock bubble doesn't necessarily mean fermentation is still occuring, just that something (like a vibration, an increase in the room temperature, a nudge fo the foot on the carboy) made it burp CO2 from solution.

beer is carbonated lightly after fermentation and will burp in secondary.

thats why the hydrometer is the way to test whether fermentation is 'done'