how long shall I count?

[jsstewar]

I remember being taught that one can count the seconds between airlock bubbles as a helpful tool to determine when initial fermentation is complete. Is it once every 30 seconds? Mine is still burping every 10 seconds and it's 2 weeks after activity started. I used a white labs belgian yeast that was 4 months passed it's expiration date and took 3 days to start the ferocious bubbling stage. thanks!

 

[Yooper]

Airlock bubbling doesn't necessarily signal fermentation activity. Airlocks can bubble due to other factors, like temperature changes or barometic pressure changes. If it gets warmer, the bubbling will increase. That's because there is dissolved c02 in solution in the beer even after fermentation is over. Colder temperatures "hold" onto the co2 more easily, so if the temperature is raised by even a degree or two, the airlock can bubble like crazy! I've taken lagers out of the lagering chamber, and with them going from 34 to 65 degrees, the airlock will bubble like mad. But fermentation is over.

The best way to see if fermentation is finished is to simply use a hydrometer instead of counting airlock bubbles.

 

[mosquitocontrol]

Someone gave you bad advice! Never use airlock as indication of fermentation. Repetitive hydrometer readings are the only thing that you should use. That, or time. I use no hydrometer most of the time and just wait 3-4 weeks.