« on: Today at 01:39:13 AM »
This brings up an idea for debate. Dont you need to clean AND sanitize? I think so, and its why I'm not a fan of spigots.
So back to the OPs question. There can be CO2 in solution being held there under the slight pressure of the airlock. Once you burp it, then CO2 comes out of solution, etc. But temp also plays a part in this. So if the temp goes up, liquid expands and CO2 comes out of solution. Also agitation can cause CO2 to come out of solution. Also, the added nucleation points caused by dry hopping can cause CO2 to come out of solution.
Airlock activity is an indication but not the only one, and it can be misleading. As stated, gravity readings are the best way to know, coupled with tasting and smelling the sample you measure. I use a number of indications to know my beer is done. (With a basic lager or ale) After airlock activity has ceased I look at the beer. If its beginning to drop clear, I will take a hydrometer reading and smell/taste it. If it smells and tastes done I wait another 4 days to a week and take a second reading. If those two readings are the same, I start my fining or chilling or bottling.