Author Topic: Missing FG???  (Read 1754 times)

Offline noodle

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Missing FG???
« on: May 21, 2011, 04:51:50 PM »
Fresh pitch from starter. Correct amount of yeast for target/actual OG. Missed FG by 5 points.

OG - 1.051
FG - 1.018 - supposed to be 1.013

Why?

thanks,

noodle

Offline hokerer

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Re: Missing FG???
« Reply #1 on: May 21, 2011, 04:58:53 PM »
Fresh pitch from starter. Correct amount of yeast for target/actual OG. Missed FG by 5 points.

OG - 1.051
FG - 1.018 - supposed to be 1.013

Why?

thanks,

noodle

how 'bout a recipe?  could be the extract or the mash schedule if all grain, the yeast, the fermentation, etc.
Joe

Offline noodle

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Re: Missing FG???
« Reply #2 on: May 21, 2011, 05:11:23 PM »
All grain

Primary for 7 days

Mash @ 152

We will run a new yeast then rack to secondary and add new wort to the fermentor.

Seems that our first batch will not finish as expected.

Additional batches will come out as expected.

thanks,

Offline tubercle

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Re: Missing FG???
« Reply #3 on: May 21, 2011, 05:13:39 PM »
All grain

Primary for 7 days

Mash @ 152

We will run a new yeast then rack to secondary and add new wort to the fermentor.

Seems that our first batch will not finish as expected.

Additional batches will come out as expected.

thanks,

Not sure what ' run a new yeast " means but if you mean pitching more yeast it won't matter if there are no more fermentables. Skip the secondary unless you nees the room.
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Offline noodle

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Re: Missing FG???
« Reply #4 on: May 21, 2011, 05:16:49 PM »
We brew every week and will reuse the yeast for a period of time. Our issue with not hitting FG seems to be with the first/original pitch of our starter.

thanks,

Offline narcout

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Re: Missing FG???
« Reply #5 on: May 21, 2011, 05:47:25 PM »
What was the recipe?

Did you aerate or oxygenate the wort?

What yeast did you use? At what temperature did you pitch? At what temperature did you ferment?

Sometimes fermentation isn't finished after only 7 days, are you sure it has already reached terminal gravity?

Offline noodle

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Re: Missing FG???
« Reply #6 on: May 21, 2011, 06:59:02 PM »
narcout -

Beersmith software - It shows an expexted OG and FG based on the recipe. We hit OG but miss FG on initital pitch only.

Wort is fully oxyginated via inline stone.

Issue is with first pitch verse second, third, fourth and so on.

I faill to see the relevance of the recipe or yeast type.

Terminal gravity is usually reached within three to four days.

thanks,



Offline a10t2

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Re: Missing FG???
« Reply #7 on: May 21, 2011, 07:12:47 PM »
I faill to see the relevance of the recipe or yeast type.

Do you have any experience brewing? Different recipes will have different FGs, and even fermenting the same recipe with a different yeast will alter the FG.

Regardless, somewhere along the line you input an expected attenuation into BeerSmith, which it is using to calculate the expected FG. It doesn't "know" anything about your beer, so it can't make a prediction.

There are some pretty experienced brewers on this forum, on the other hand, so if you'd tell us the recipe we *could* make a prediction.
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Offline bluesman

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Re: Missing FG???
« Reply #8 on: May 21, 2011, 07:27:30 PM »
Detailed recipe please. This will help us get to the bottom of your potential issue.

Thanks.
Ron Price

Offline noodle

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Re: Missing FG???
« Reply #9 on: May 22, 2011, 03:34:57 AM »
This is why I ask -

We will run the same yeast for four batches starting as follows - Pub Ale, ESB, ESB, Brown Ale

Pub - Missing FG
ESB - Hit numbers as expected
ESB - Hit numbers as expected
Brown - Hit numbers as expected

Second run as follows - Brown, ESB, ESB, Pub
Brown - Missing FG
ESB - Hit numbers as expected
ESB - Hit numbers as expected
Pub - Hit numbers as expected.

In both cases, the first beer of the run doesn't finish as expected.

Any ideas?

Thanks,

Offline stlaleman

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Re: Missing FG???
« Reply #10 on: May 22, 2011, 04:45:23 AM »
I'll take a shot at this. If I understand correctly, you are repitching the yeast three more times, each of those times you hit the expected FG, but never the first time. Therefore the starter is to blame, either too small or you somehow stressed the yeast. Revisit that aspect of your brewing.

Offline noodle

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Re: Missing FG???
« Reply #11 on: May 22, 2011, 06:24:21 AM »
stlaleman -

Thanks, this is what I need to figure out. I make the starter 1-2 days prior to brewing and everything looks good with it.

Any advise as to what I'm looking for?

Thanks for your help and direction.

Offline hokerer

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Re: Missing FG???
« Reply #12 on: May 22, 2011, 08:30:34 AM »
stlaleman -

Thanks, this is what I need to figure out. I make the starter 1-2 days prior to brewing and everything looks good with it.

Any advise as to what I'm looking for?

Thanks for your help and direction.


Try messing around with the Pitching Rate Calculator here...

http://www.mrmalty.com/calc/calc.html

and see if your starter is big enough.  A re-pitch is going to be a much higher pitching rate than a 1-2 day starter so it makes sense that you're getting full attenuation on batches 2, 3, 4.
Joe

Offline denny

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Re: Missing FG???
« Reply #13 on: May 22, 2011, 09:01:52 AM »
Beersmith software - It shows an expexted OG and FG based on the recipe. We hit OG but miss FG on initital pitch only.

Beware of ANY software that does this...it's a guess and it's bogus.  The software is using the attenuation rating of the yeast, which is actually meant only as a method of comparing one yeast to another, NOT as a way of predicting FG.  Wort composition is actually much more important to FG and any yeast can yield a wide range of attenuation depending on the wort you pitch it into.
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Offline Pawtucket Patriot

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Re: Missing FG???
« Reply #14 on: May 22, 2011, 09:30:09 AM »
Wort composition is actually much more important to FG and any yeast can yield a wide range of attenuation depending on the wort you pitch it into.

Which is why other posters have been asking for detailed recipe info.  I don't know why the OP is so reluctant to provide this -- we're only trying to help!  It's sort of SOP on this forum to provide your recipe if you want a proper diagnosis of a problem.
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