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Old 04-07-2014, 09:50 PM   #21
fearwig
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I have never had BS or Brewtarget guess my FG correctly, usually they are high by 2-5pts. I have resigned myself to thinking my system is just too different from whatever ideal BS has in mind.

Now that I read your batch volume I suspect my advice is less valuable than your experience, but some heat (up to maybe 74?) would seem to be in order.
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Old 04-07-2014, 10:04 PM   #22
boydster
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Your temps are right in line with what I do for 05. I think the advice to warm it up a few degrees is good, and rouse the yeast. Is it possible your thermometer you used for the mash needs to be calibrated?

 
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Old 04-07-2014, 10:13 PM   #23
Weezy
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These kinds of posts make me think that the person's mash temp may have been higher than they think, or insufficient aeration.

 
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Old 04-07-2014, 10:20 PM   #24
fearwig
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Mash temp issues are my go-to for high FG because incomplete conversion is easy to do if you don't get adequate mash circulation and even denature some of the mash early on if it's fired. You can sometimes pitch in totally unaerated wort and get good attenuation, eventually. You won't get that from semi-converted wort, ever. Just my first hunch, though.
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Old 04-07-2014, 11:12 PM   #25
Beernik
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To get that much attenuation, I'd drop the Carapils. If you want +80% attenuation, any Carapils is going to be working against you.

Add a flaked or a torrified grain if you are worried about head retention.
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Old 04-08-2014, 01:26 AM   #26
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It was pointed out earlier that that adding simple sugars inhibit yeast from completely metabolizing maltose in wort. A while back I came across this academic paper describing this phenomenon. Perhaps, as one poster pointed out, sucrose is less problematic than dextrose which is what I use. In the future, you might consider an approach that works for me which is to add the sugar as a sterol syrup near the end of fermentation. I have regularly fermented a Pliny the Younger clone from 1.091 to 1.010 or below. In one case, I got it down to 1.008. But, I have found that I needed to add the bulk of the sugar near the end of fermentation rather than in the boil.

 
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Old 04-08-2014, 01:58 AM   #27
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Quote:
Originally Posted by seanppp View Post
34 gallon batch.

84% Pale
7.5% cane sugar
6% Carapils
2.5% Crystal 40

Mashed at 150F.
Servomyces in boil.
Safale US-05. Rehydrated yeast before pitch.

1.075 OG. Pitched at 18C (64.4F).
2 days after pitch: Set to 19C (66.2C). [didn't take a gravity]
3 days after pitch: 1.040.
4 days after pitch: 1.030, set to 20C (68F).
5 days after pitch: 1.022.
6 days after pitch: 1.020, set to 22C (71.6F).

Thanks!
I'd expect to get to at least 1.015 with that, and you still might.

Check your thermometer in some boiling water.

 
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Old 04-08-2014, 11:28 AM   #28
seanppp
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Thanks for the great advice everybody. You are right, I should calibrate my therometer.

Guess what? I jumped the gun a bit. Since the beer was at 1.020 for two days in a row (6 & 7 days after pitching) I *thought* it finished attenuating so I turned the chilling system up to 71.6F hoping it would clean up the fermentation byproducts, and then I posted my underattenuation question. Well, I just checked it today (9 days after pitching) and it was at 1.014! So even though it "stalled" for two days, the push in temperature really helped it! So I'll check it tomorrow and see where it is. Very interesting...

 
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