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Old 11-12-2012, 09:45 PM   #11
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Quote:
Originally Posted by tre9er
What about temp control? How do you do it and what were the actual beer temps during fermentation? If you cooled at any point, it could have encouraged the yeast to fall out. I always recommend a slight warming after initial fermentation has slowed down. That encourages yeast to stay in suspension. A gentle swirl can help, too.
I do that simply by keeping the house cold... Fermentation temps stayed at about 67-69 degrees for the entire time, so inside the fermenter could have been somewhere near 72° at the peak of yeast movement. I swirled one fermenter and a lot of gas was released, but I haven't noticed anymore movement out of it. Fwiw, there was very little yeast slurry at the bottom of that fermenter when I did that, so the cells obviously didn't multiply very much.

I am hoping that this new starter hits high krausen in the next few days, so it will prove that the wort is indeed fermentable... If it never hits high krausen, I will cold crash and take a gravity reading of this forced fermentation to see if it moved at all and try to determine whether or not its salvageable.

 
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Old 11-12-2012, 09:54 PM   #12
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Also, taste it. Is it cloyingly sweet still? Gravity obviously matters, but I also wonder how it tastes.
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Old 11-12-2012, 10:05 PM   #13
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I suspect the following:
1. Way underpitched and a lot of really stressed out yeast that just plain quit
2. A high amount of less fermentable malt in that grain bill
3. A thermometer that is off- a 2-3 degree difference in the wrong direction can create a very different wort than expected

Just because you are getting airlock activity when you move the primary does not mean any further fermentation is actually occurring, just that gasses are escaping and it could just be off gassing. If there is any question as to what the beer is doing then take another reading.

If you elect to re-pitch then definitely do it at high krausen so you don't add any more stressed out yeast to the batch Raise the temp a bit and keep the yeast in suspension. Give it a week and take a reading.
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Old 11-12-2012, 10:05 PM   #14
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Quote:
Originally Posted by tre9er
Also, taste it. Is it cloyingly sweet still? Gravity obviously matters, but I also wonder how it tastes.
Yeah, it's definitely sweet... It has a GREAT flavor to it, but very sweet still...

If it can get anywhere closer to 1.015-1.020 I think it would be great and I would consider that a full fermentation for it given the ingredients and mash temp. Bt it's got a little ways to go before it gets there...

 
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Old 11-13-2012, 12:29 AM   #15
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Something to think about... You only have 64% base malt in that recipe. With all the trouble you're having getting it to ferment to where you want it, I would seriously think about not using so much other malts moving forward.

I do my best to have at least 80% base malt in my recipes. If I go lower, there's a damned good reason for it, and it's not all that far below that level. I prefer to have more like 85-90% base malt. Even my DARK ales have 80% base malt (or better)...
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Old 11-13-2012, 12:49 AM   #16
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Quote:
Originally Posted by Golddiggie
Something to think about... You only have 64% base malt in that recipe. With all the trouble you're having getting it to ferment to where you want it, I would seriously think about not using so much other malts moving forward.

I do my best to have at least 80% base malt in my recipes. If I go lower, there's a damned good reason for it, and it's not all that far below that level. I prefer to have more like 85-90% base malt. Even my DARK ales have 80% base malt (or better)...
True, but those should have contributed some fermentable sugars to the base as well...

But definitely a point to note.

 
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Old 11-13-2012, 01:11 AM   #17
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Quote:
Originally Posted by tre9er View Post
Pitch at high krausen. That's a lot of aromatic/cara, FWIW. .
It's alot of cara but aromatic malt is fermentable, so I'm not sure what's going on it. (You can actually use 100% aromatic malt as a base malt, although I wouldn't recommend it for best flavor- it does have enough DP to convert itself. It's just a "higher" Munich malt).

I think there are two main causes of this stuck/slow fermentation:

1. Underpitching. It was a huge underpitch, and that is a big issue.
2. Too high mash temp. If it was 155, it might not be too high. But if the thermometer was even 1.5 degrees off, then it WAS too high. That could be a contributing cause.
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Old 11-13-2012, 03:35 AM   #18
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I feel pretty confident in the thermometer accuracy, I used it a few weeks prior at 153° for a stout that finished at 1.1014, and again for a smoked pale ale at 150° that has been VERY active...

I'm not ruling out human error though.

 
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Old 11-13-2012, 04:07 AM   #19
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Quote:
Originally Posted by HollisBT View Post
I feel pretty confident in the thermometer accuracy, I used it a few weeks prior at 153° for a stout that finished at 1.1014, and again for a smoked pale ale at 150° that has been VERY active...

I'm not ruling out human error though.
Then I say it's the recipe used is the culprit.
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Old 11-13-2012, 04:46 AM   #20
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Thermometers become less accurate as temperatures go up, so it may read dead on at room temperature but be way off at mash temps. My floating thermometer runs 4-5 degrees higher at mash temperatures than it should. If yours is way off that 155F mash could have been 160 or higher. Nevertheless, even a 160F beer should ferment out more than 20 points.

Between the golden promise and aromatic you definitely have enough diastatic power to convert those starches, so the recipe is fine.

Your most likely culprit is underpitching and underaerating. Shake the **** out of your fermenters and add some nutrient.

 
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