Author Topic: Does fermentation ever totally cease?  (Read 888 times)

Offline fyouberg

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Does fermentation ever totally cease?
« on: March 05, 2013, 07:45:46 PM »
That's my question.  Let's say you start with a relatively high OSG of .070.  If you ferment in a 5 gal. Glass carboy with a basic fermentation lock and steady temperature, will the bubbles of CO2 ever totally stop or do the just keep getting slower and slower.  My stouts been going for 10 days now and fermentation has slowed significantly (1 bubble/90 sec.).  I really don't want to open is up until I'm pretty sure that the SG has reached it's low point.  Is it basically done or should I wait longer?
If your yeast is happy, it can't help but be a good day.

Offline hokerer

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Re: Does fermentation ever totally cease?
« Reply #1 on: March 05, 2013, 07:56:15 PM »
That's my question.  Let's say you start with a relatively high OSG of .070.  If you ferment in a 5 gal. Glass carboy with a basic fermentation lock and steady temperature, will the bubbles of CO2 ever totally stop or do the just keep getting slower and slower.  My stouts been going for 10 days now and fermentation has slowed significantly (1 bubble/90 sec.).  I really don't want to open is up until I'm pretty sure that the SG has reached it's low point.  Is it basically done or should I wait longer?

Repeat after me:  bubbles does not equal fermentation!  say it ten times

Bubbles often simply indicate off gassing as temperatures change.  There's lots of reasons for bubbles other than fermentation.
Joe

Offline duboman

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Does fermentation ever totally cease?
« Reply #2 on: March 05, 2013, 08:04:32 PM »
That's my question.  Let's say you start with a relatively high OSG of .070.  If you ferment in a 5 gal. Glass carboy with a basic fermentation lock and steady temperature, will the bubbles of CO2 ever totally stop or do the just keep getting slower and slower.  My stouts been going for 10 days now and fermentation has slowed significantly (1 bubble/90 sec.).  I really don't want to open is up until I'm pretty sure that the SG has reached it's low point.  Is it basically done or should I wait longer?

Repeat after me:  bubbles does not equal fermentation!  say it ten times

Bubbles often simply indicate off gassing as temperatures change.  There's lots of reasons for bubbles other than fermentation.

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Offline jamminbrew

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Re: Does fermentation ever totally cease?
« Reply #3 on: March 05, 2013, 08:42:01 PM »
I generally give my beers 14-21 days before checking gravity. Have patience. Yeast will finish when they are done. And +100 to Hokerer... Bubbles are not a great way to judge whether the yeast are done or not. 

To answer your question, yes, eventually fermentation does cease. When alcohol levels get too high, or food is all gone, yeast will flocculate out or die off. But they will keep working for months, just at a vastly lower rate than the first couple of weeks.
Brettanomyces will work for months and more, cleaning up the leftovers from the original fermentation.
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Offline fyouberg

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Re: Does fermentation ever totally cease?
« Reply #4 on: March 06, 2013, 04:56:39 AM »
Hope I'm doing this reply thing right.  OK, my bubble vigil will end immediately.  It's time for the trusty hydrometer.  Thanks all for the help and advice.  I will also try DWHAHB.
If your yeast is happy, it can't help but be a good day.

Offline davidgzach

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Re: Does fermentation ever totally cease?
« Reply #5 on: March 06, 2013, 05:10:47 AM »
Hope I'm doing this reply thing right.  OK, my bubble vigil will end immediately.  It's time for the trusty hydrometer.  Thanks all for the help and advice.  I will also try DWHAHB.

Don't forget the R in front of DWHAHB for 'Relax!'. 

Dave
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Offline garc_mall

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Re: Does fermentation ever totally cease?
« Reply #6 on: March 06, 2013, 09:41:05 AM »
Hope I'm doing this reply thing right.  OK, my bubble vigil will end immediately.  It's time for the trusty hydrometer.  Thanks all for the help and advice.  I will also try DWHAHB.

Don't forget the R in front of DWHAHB for 'Relax!'. 

Dave

+1

Relaxing is the most important part. Remember, it's a hobby, not a business. If you make a mistake or two, you will still have beer.
In a Keg: Flanders Red Ale, Rye Altbier, Cascade/Topaz Pale
Fermenting: Flanders Red, Saison