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05-23-2010, 01:31 PM   #1
redfox
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 attenuation question

if the OG = 1.065 and the yeast strain has an attenuation of 70-76 percent, what SHOULD the FG be?

I know I should be able to figure this out, but...it's early here!

Thanks!

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05-23-2010, 01:55 PM   #2
danielinva
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FG = OG-((OG-1)*Attenuation)
so
FG=1.065 - (.065*.75) = 1.065-.049 = 1.016

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05-23-2010, 02:10 PM   #3
redfox
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thank you, danielinva!

yes, that makes sense.

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05-23-2010, 03:01 PM   #4
homebrewer_99
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For many yeasts 75% is within the attenuation range.

For a quick computation I divide the OG by 4 and the answer is the FG.

Of course, danielinva's process is more precise.

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05-23-2010, 05:26 PM   #5
david_42
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Quote:
 Of course, danielinva's process is more precise.
Although you really should calculate the range, not just one value.

There's always ways to make brewing more complicated.
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05-23-2010, 05:36 PM   #6
TipsyDragon
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your FG should be between 1.020 and 1.015. don't be alarmed if its a couple points outside this range.

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