Confused about my fermentation

ibracn · January 17, 2015, 5:01am

I’ve got a question or concern I would like help with. The last four all grain batches I’ve brewed, I have had a fermentation that will not quit. The air lock bubbles for 14+ days. My amber ale was at 16 days until I cold crashed it and it stopped. It still turned out good but the 16 days of bubbling in the air lock was not normal for me (OG 1.053, FG 1.008). My cream ale lasted 12 days but turned out great (OG 1.047, FG 1.002). My copper ale lasted 14 days until I cold crashed it…kegged it yesterday so have yet to taste it (OG 1.057, FG 1.006). I have a Kolsch that is still active at 10 days (1.044). I combined a brew and had a team brew lasted 5 days as I have experienced in the past. The only thing different between all of them is that I used a new counter flow chiller on the brews that bubbled a long time. Everything else is the same. My Team brew was chilled by an immersion chiller prvided by one of the team members.

I know that the length the bubbling occurs isn’t neccarily indicitive of fermentation, but taking a gravity reading is more exact. I have not done gravity readings due to fear of oxidation and contamination. What do you guys think is going on here? I’ve cleaned my counter flow chiller 2x with PBW and ran Star San through it 3x. I’m confused. All of my brews before this counter flow chiller, the fermentation lasted 5-7 days. Any advice?

Sorry to be so lengthy.

frenchie · January 17, 2015, 11:44am

Give us an idea of your fermentation temps and schedule and yeast. In my experience, cooler temps equal longer ferments, and then when I raise the temp toward the end of fermentation, the airlock keeps bubbling slightly, sometimes for days, but only because co2 is being released at the higher temp, not because of fermentation.

You’re right, though. Gravity readings are the only way to know for absolutely sure, but some of the more experienced brewers here have so many brews under their belts that they can pretty much tell when it’s done without a reading. I’m not quite there yet. Doesn’t really sound to me like there’s anything amiss with your beer, though.

Good luck, I’m sure some more experienced folks will be able to give you a little more insight than I have.

:cheers:

Ron

jimrmaine · January 18, 2015, 8:28pm

Hmm, what yeast are you using? Unless my math is wrong, you got between 80 and 95% attenuation on all 3 examples you gave. Seems higher than usually expected.

ibracn · January 20, 2015, 9:13pm

My fermentation temps are 68 degrees for everything but the Kolsch, that is set at 60.

The yeast I’m using is the Wyeast 1056 and used the Wyeast Kolsch yeast. I checked my gravity reading for the Kolsch last night and it came in at 1.016 which is higher than expected (goal was a 1.008). The Kolsch bubbled for 12 days before I cold crashed it, then it stopped.

My Copper Ale doesn’t taste like I expected…not like the first time I brewed it. I’m going to let it set for another couple of weeks and give it another try. Guess I will plug away and see what happens.

drgonzo · January 20, 2015, 9:18pm

How does the copper ale taste? too sweet? too dry? Is it possible your beer is just off gassing trapped CO2 after active ferm, giving the appearance of continued ferm? Do you test the SG?

ibracn · January 20, 2015, 9:29pm

Taste sweet with a different taste that I can’t describe…new to the game so struggle with defining odd/different taste. It does not take like metal or anything like that but just a little odd.

I do test OG and FG.

drgonzo · January 20, 2015, 10:38pm

The sweet taste leads me to think that your beer was not done fermenting. I would try warming up the fermentation. set you carboy on a heating pad and wrap it in towels if you do not have a warmer place in the house.

bwmac2 · January 21, 2015, 2:11am

Are you pitching enough yeast ? A big starter of fresh yeast may do the trick. Check out Mr Malty pitch rate calculator. I had similar problems with some of my early brews.

ibracn · January 21, 2015, 2:11pm

I’ve been using a yeast starter with about 700 ml of wort using a smack pack so I’m guessing I have plenty of yeast.

rebuiltcellars · January 21, 2015, 2:43pm

Those FG numbers are much lower than you should get. Combined with the use of a new CFC and continuous outgassing, I’d check for contamination. There may be some bug hiding in your chiller that is eating sugars that the yeast normally can’t. Brett immediately comes to mind as a candidate for this, though the time frame would be very short for that effect from a Brett infection. Could the strange flavor in the copper ale be reminiscent of wet leather or horse sweat? How are you sanitizing the chiller before use?

By the way, 700 ml starter is NOT a lot of yeast. It is enough to get the yeast from the smack pack active, but not enough to grow the population by any significant quantity. For a typical 1.050 beer, I’ll use 1.5 - 2 liters.

loopie_beer · January 21, 2015, 5:40pm

[quote=“rebuiltcellars”]Those FG numbers are much lower than you should get. Combined with the use of a new CFC and continuous outgassing, I’d check for contamination. There may be some bug hiding in your chiller that is eating sugars that the yeast normally can’t. Brett immediately comes to mind as a candidate for this, though the time frame would be very short for that effect from a Brett infection. Could the strange flavor in the copper ale be reminiscent of wet leather or horse sweat? How are you sanitizing the chiller before use?

By the way, 700 ml starter is NOT a lot of yeast. It is enough to get the yeast from the smack pack active, but not enough to grow the population by any significant quantity. For a typical 1.050 beer, I’ll use 1.5 - 2 liters.[/quote]
I agree. Those FG are pretty low. Like RC asks, how are you cleaning/santizing your CFC? Are you measuring FG and with what? What are you fermenting in? Does the beer start tasting funny/bad with age? If you do have an infection all soft items must go.

ibracn · January 21, 2015, 5:55pm

I ran PBW through the CFC twice and ran Star San through it three times before using. I run Star San through it each time before using it as well as store it with SS in it. I ferment in a glass carboy and it sets in my chest freezer with temp control. I check FG with a hydrometer and my OG with a refractometer I calibrate it before each brew session. All of what I brewed has tasted really good (IMO) with the exception of this Copper Ale I last brewed…I have yet to taste the Kolsch.

I’m doing everything the same as I have always done in the past. In the past, the fermentation (bubbling) has lasted 5-7 days. The only thing I have changed is the CFC. I think my next batch will be cooled with my immersion chiller and see what happens…going back to the basics I guess. Thanks for all of the questions/suggestions…much appreciated.