Author Topic: Fermentation completion  (Read 577 times)

Offline JohnnyC

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Fermentation completion
« on: February 26, 2018, 02:44:42 PM »
If:
1. gravity readings are consistent over 3 days and the attenuation of the strain are within parameters, the beer is  done, correct?
2.If 1 is correct, there is nothing more for the yeast to do and won't "clean up" anything, correct?
C. It doesn't matter how long it's taken to get to this point, 3 weeks or 7 days, correct?

Proper sized starter, it was temp controlled, there are no off flavors/aromas in the sample.

Online Robert

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Re: Fermentation completion
« Reply #1 on: February 26, 2018, 02:49:16 PM »
Correct x 3.
Rob Stein
Akron, Ohio

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Offline kramerog

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Re: Fermentation completion
« Reply #2 on: February 26, 2018, 03:07:03 PM »
I don't think 2 necessarily follows from 1 even for ales, but 2 usually follows from 1.  I think that diacetyl reduction could happen on day 4 of the same readings.  But since everything tastes fine you are good to go.

Offline flars

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Re: Fermentation completion
« Reply #3 on: February 26, 2018, 03:36:04 PM »
1.  A yeast like WY 3787 can sometimes take a week to drop the last one or two gravity points.  FG depends upon the yeast and how fermentable your wort is.  The same yeast used in two different worts can finish with two different final gravitys.

2.  Yeast cleans up throughout the entire fermentation.  As the fermentation ends there is just less to clean up.

3.  Correct.  We just need to give the beer time to get to that point.  This is a lot easier if you have brewed the beer with the same yeast a couple of times.

Online Robert

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Re: Fermentation completion
« Reply #4 on: February 26, 2018, 04:16:54 PM »
There will be no further cleanup once the FG has truly been achieved.  Cleanup begins in earnest when yeast transitions from primary to secondary fermentation,  around 50% of OG,  when the easy food (maltose) is gone and it starts to work on the other consumables, more complex sugars and its own earlier fermentation products, in preparation for dormancy.  The 3 day rule is pretty good in most cases. If you really want to be sure, the only way is to do a FFT at the outset.
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.