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General Category => All Grain Brewing => Topic started by: dons on August 10, 2011, 06:01:55 PM

Title: Fermentation taking LOOOONG time
Post by: dons on August 10, 2011, 06:01:55 PM
Okay, I am making a replica of an IPA done previously with the only changes
being the grains - now using 10.5 pounds Munich and 1 pound of Victory instead of the
previous 10.5 pounds domestic 2-row, 1 pound Crystal 45 and .5 pounds Cara pils.

I would expect the timing to be about the same.  Instead, I have something strange.  The
first brew was bottled 4 weeks after brewing, but it has now been 5 weeks since brewing day
and my bubble rate is 7 seconds.  Yes, I have done gravity readings.  And for the past 7 days,
the 3 readings have been 1.021 (the og of the previous brew was 1.011).  So, I'm not sure if
fermentation is done or not, but the activity is odd.  Could a simple change of grain make that
much difference in fermentation time - presuming it is still fermenting?

As much as possible, the rest of the process was pretty much the same.  If I'm at 7 seconds
now (and, I know, I should put little faith in bubble timing), seems like it will be a long time
until I can bottle.  I am not interested in making bottle rockets at this time.

And, by the way, the taste is pretty good. 

Seem okay to you?
Thanks!
Don
Title: Re: Fermentation taking LOOOONG time
Post by: ukolowiczd on August 10, 2011, 06:04:46 PM
5 weeks and it's still bubbling every 7 seconds!? Did you mean 5 days? I have definitely had different mash efficiencies and yeast attenuation rates with different grains. I've never used mostly Munich though so I'm no help there.
Title: Re: Fermentation taking LOOOONG time
Post by: dons on August 10, 2011, 06:07:04 PM
I mean 5 weeks.  I am 2 weeks into the secondary at this time.  The primary was down to about
90 second bubbles.  Racked to secondary and dry-hopped.  This is unbelievable activity, huh?
Title: Re: Fermentation taking LOOOONG time
Post by: ukolowiczd on August 10, 2011, 06:09:04 PM
yeah, wow! what was your OG and what yeast are you using?
Title: Re: Fermentation taking LOOOONG time
Post by: blatz on August 10, 2011, 06:10:35 PM
what yeast and did you make a starter?
Title: Re: Fermentation taking LOOOONG time
Post by: dons on August 10, 2011, 06:20:29 PM
Yeast on the first brew was WLP001 and second yeast was Wyeast 1056.
OG was 1.061, same as expected.  Expected FG is 1.015.
Title: Re: Fermentation taking LOOOONG time
Post by: blatz on August 10, 2011, 06:24:07 PM
if you didn't make a starter, you underpitched.  and if the yeast was old/close to expiration, you dramatically underpitched, which might explain your long fermentation.

Title: Re: Fermentation taking LOOOONG time
Post by: dons on August 10, 2011, 06:32:28 PM
Good point, but it was a good yeast (I know my supplier) and I did a good starter.  Always do.
Of course, what I'm so worried about is that there is an infection - but there is nothing of that in
the taste.
Title: Re: Fermentation taking LOOOONG time
Post by: denny on August 10, 2011, 06:37:23 PM
There have been reports of Munich not converting as completely or quickly as pale malt, depending on the maltster of the Munich.  Maybe you didn't get full conversion or produce as fermentable a wort?
Title: Re: Fermentation taking LOOOONG time
Post by: tschmidlin on August 10, 2011, 06:38:31 PM
Airlock activity is not a good indicator of fermentation.  If the SG has been stable for more than a couple of days, it is done.  Bottle it.  If you are paranoid about it, warm it up to the mid 70s for a couple of days to encourage the yeast to finish, and keep checking the gravity.  Don't forget to correct for the temp difference.
Title: Re: Fermentation taking LOOOONG time
Post by: bigchicken on August 11, 2011, 05:23:37 PM
I have gone from very little airlock activity to feverish after racking to the secondary while dry hopping. It could just be a reaction from adding hops. I've also had this happen with the addition of coffee beans in the secondary.
I agree with Tom's response.
Title: Re: Fermentation taking LOOOONG time
Post by: dons on August 15, 2011, 03:11:24 PM
Okay, guys, I hear you.  And I trust ya - pretty much.

But riddle me this:  I checked that nasty old bubble rate this morning and it has now gone to 5 seconds!!!  So, given that I am bottling, not kegging, what is going to stop this bubbling so that I don't blow up every bottle.  Yes, the sg is perfectly leveled off to 1.020.  So, if fermentation is not happening, what is the yeast eating and what will save my ceilings?

Title: Re: Fermentation taking LOOOONG time
Post by: denny on August 15, 2011, 04:06:01 PM
Okay, guys, I hear you.  And I trust ya - pretty much.

But riddle me this:  I checked that nasty old bubble rate this morning and it has now gone to 5 seconds!!!  So, given that I am bottling, not kegging, what is going to stop this bubbling so that I don't blow up every bottle.  Yes, the sg is perfectly leveled off to 1.020.  So, if fermentation is not happening, what is the yeast eating and what will save my ceilings?



I think you're confusing fermentation with CO2 outgassing here.  Both will produce bubbles in the airlock, but outgassing can happen after fermentation is finished, as shown by your steady gravity reading.
Title: Re: Fermentation taking LOOOONG time
Post by: dons on August 15, 2011, 04:16:30 PM
Thanks, Denny.  Yes I am.  I misspoke.
But isn't the CO2 exhaust just as dangerous for bottles?
Or is it miniscule - which is why I'm told to go ahead and bottle?

Title: Re: Fermentation taking LOOOONG time
Post by: Jimmy K on August 15, 2011, 04:31:53 PM
Thanks, Denny.  Yes I am.  I misspoke.
But isn't the CO2 exhaust just as dangerous for bottles?
Or is it miniscule - which is why I'm told to go ahead and bottle?


I once saw some calculations on priming sugar additions - take home was that the priming sugar rates we use depend on that dissolved CO2 to create the predicted carbonation levels.

Here is that thread, see the last message.

http://groups.google.com/group/cider-workshop/browse_thread/thread/6bf0339cb32848e7/bfa5908288cce23f?lnk=gst&q=carbonation#bfa5908288cce23f
Title: Re: Fermentation taking LOOOONG time
Post by: denny on August 15, 2011, 04:39:40 PM
Thanks, Denny.  Yes I am.  I misspoke.
But isn't the CO2 exhaust just as dangerous for bottles?
Or is it miniscule - which is why I'm told to go ahead and bottle?



Most priming calculators I've seen take the temp of the beer into account.  That supposedly accounts for the dissolved CO2.  Additional CO2 will only be created by the amount of priming you add.