This past Sunday, I brewed a Belgian Witbeir from a mini-mash kit I got online. This is only my second attempt at homebrewing, and so I had a question regarding fermentation. I noticed yesterday (as well as today) that there seems to be very little activity in my airlock. Within only a few hours of pitching my yeast, a very aggressive fermentation set in then suddenly seemed to putter out. I used Safbrew S-33 dry yeast and I rehydrated it with 4oz of warm water before pitching it onto my wort. There's some sediment in the bottom of my airlock (3-piece) from when the beer started to blow off during the onset of fermentation, so I was curious if the airlock being dirty has anything to do with it? Should I be concerned or should I just let the beer do it's thing? Any comments or advice would be appreciated. Cheers!
That is true if you have a leak in your fermenter. Air lock activity is a great indication of how you beer is fermenting. I have never used the yeast the op is using so I cannot comment on that.If I have a beer that starts off strong and shuts down sooner then I think is normal I will check my seal then swirl the fermenter to get the yeast back in suspention. If I don't have activity in my air lock for a couple days that soon after pitching I'll take a gravity reading to descide if I need to pitch more yeast.
how long would you say this aggressive fermentation took? what was your original gravity? what temp are you fermenting at? in all honesty the bulk of you fermentation might be done. give it 2 weeks and take a gravity reading. also if you have some shmaltz in your airlock you should wash and re sanitize it... and relax your beer is most likely fine...
Do you see other signs of fermentation: krausen, churning inside the carboy, etc? If the other signs of fermentation are there and you're just not getting bubbles in the airlock, it could be that the airlock got clogged and the gas is escaping out the side or some other way. (You should wash the airlock with warm water, re-sanitize it, and put it back in place regardless. You can put a little foil over the hole in the stopper while you're doing this if you want to be super safe.) If you don't see other signs of fermentation--if the krausen has fallen, there's no churning, and the beer is starting to clear--then your fermentation is probably finished. This is probably what happened. There aren't too many things that can stop an agressive fermentation once it starts--other than running out of sugars.
I've only done one homebrew batch and it was using this yeast. (just under 4 weeks ago I brewed, just started drinking them a few days ago) It started fermenting very quickly and aggressively for me, I saw very little activity in airlock after 48 hours. Based on my gravity readings this yeast seems to start fermenting quickly, and does its work quick. It was also a bit warmer than I wanted in my environment so that may have expedited my fermentation as well. I'm no expert but your experience sounds similar to mine. Don't worry have a homebrew.
FYI, this is a very common observation/question around here. Most of the time, the yeast have just finished the bulk of attenuation and are more into the cleanup phase. As already said, give it a week (or two) and take a gravity reading. (Then another 3 days later.) Edit: another thought...make sure your fermenter's temperature remains in a good range for the yeast while you're waiting.
