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Old 04-06-2014, 02:34 AM   #11
tyler2you
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Jan 2014
Madison, Alabama
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From 1.075 to 1.020 is 73.3% attenuation.

That's typically what I get when using something like WLP002 (English Ale Yeast). WLP001 or WLP007 usually get me into the mid 80% range.

What yeast did you use and what was your mash temp? Mashing in the 145 to 147 range for 90 minutes usually gets me higher attenuation as well.

 
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Old 04-06-2014, 07:30 AM   #12
seanppp
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Jun 2013
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Hey guys, thanks for the responses. Here's the recipe:

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!

 
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Old 04-06-2014, 08:18 AM   #13
F_R_O_G
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Nov 2013
north Seattle, wa
Posts: 210
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you really have 2 options, just like anyone else who doesn't get there finishing gravity. heat the fermentor to 77deg or add more yeast. heating it up is by far the easiest. if heat doesn't work do a force fermentation test to find out if your yeast has lost viability/vitality. next time don't add any refined sugar as this can cause the yeast to consume just the sugar then stop and not consume the more complex sugar from the pale malts

one other thing I've noticed is that sometimes the LHBS doesn't store the dry yeast properly, if the yeast is not stored in the refrigerator than the expiration date is only 3 months from the manufacturer date.

 
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Old 04-06-2014, 02:16 PM   #14
Beernik
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Jun 2009
Lopez Island, WA
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I would think the complete fermentability of the sugar would be countered by the unfermentability of the Carapils. 150F is kind of middle of the road for mash temps. So I would guess a middle of the road attenuation ~ 75% - 78%.

So, I'm thinking with a little coaxing, you might get to ~ 1.015. But it wouldn't surprise me if it stopped at 1.018.
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Old 04-07-2014, 01:08 AM   #15
F_R_O_G
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Nov 2013
north Seattle, wa
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Quote:
Originally Posted by Beernik View Post
I would think the complete fermentability of the sugar would be countered by the unfermentability of the Carapils.
unfortunately it doesn't really work that way, yeast will ferment glucose from the refined sugar with almost no effort. then it will either stop or switch gears to ferment the maltose from the 2row pale malt. if the yeast has decided to stop you will have to put more yeast in to restart the fermentation. yeast will completely ignore unfermentable sugar.

 
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Old 04-07-2014, 03:40 AM   #16
Beernik
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Jun 2009
Lopez Island, WA
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Nice. You tell me "it doesn't really work that way" and then go on to explain how it works that way. Let me clarify...

7.5% of a grain bill that is 100% fermentable + 6% of a grain bill that is 0% fermentable is a lot like having 1.5% of a grain bill that is 100% fermentable.

Of course, it's not going to be quite that even. Table sugar is ~ 42 ppg. Carapils is ~ 33 ppg. So it will ferment like having more than 1.5% of the grain bill being sugar, but not a whole lot more. I'm coming up with ~ 2.8%.

The bottom line is you can't expect the sugar to drop the FG much lower than if the recipe was all malt.

If Safale-05 normally gives 78% attenuation, seanppp shouldn't expect much more than 78% attenuation. (78% is what BrewPal gives me for the yeast. I don't know how accurate that is.)
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Old 04-07-2014, 06:07 AM   #17
F_R_O_G
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Nov 2013
north Seattle, wa
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sorry, I wasn't trying to be rude, I obviously didn't understand what you were trying to say. I don't think you understood what I was trying to say.

what I'm getting at is the biological property of yeast. yeast, being temperamental, can't allays be put into an equation and expect the same results. If they feed on simple sugars it can be hard for them to switch to more complex sugars

as I read more about it I don't think this would be the issue here. table sugar is sucrose. Glucose is the sugar that can cause problems.

 
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Old 04-07-2014, 07:00 AM   #18
seanppp
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Jun 2013
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Well, I guess the real question is how can I avoid this happening again (assuming the same grain bill). My recipe was based on the Pliny grain bill (though I upped the Carapils and lowered the Crystal, but the sum of those two is the same), and they get the attenuation that I was wanting.

I added servomyces, oxygenated, and rehydrated the yeast, so I'm thinking it was maybe my temperature program.
-1.075, pitched at 64.4F
-1 day: 64.4F
-2 days: Set to 66.2F
-3 days: 1.040, 66.2F
-4 days: 1.030, set to 68F
-5 days: 1.022, turned off cooling
-6 days: 1.020 (terminal), still 68F (never got warmer after turning off cooling)

It seems to me like it mowed through the sugar pretty well during the first 4 days, which is great, but maybe I should have done this:
-Pitch at 64.4F
-1 day: Set to 66.2F.
-2 days: Set to 68F
-3 days: 68F
-4 days: Turn off cooling.

What do you think?

 
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Old 04-07-2014, 03:53 PM   #19
pm5k00
 
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Apr 2011
Cibolo, TX
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34 gallon batch? Is that correct? How much and how viable was the yeast used?

 
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Old 04-07-2014, 09:31 PM   #20
seanppp
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Jun 2013
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Yeah. 34 gallon batch. I used the Mr Malty yeast pitching calculator to determine the pitch.

 
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