Author Topic: Can Estimated Final Gravity be Modified?  (Read 865 times)

Offline philm63

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Can Estimated Final Gravity be Modified?
« on: October 15, 2019, 12:46:09 PM »
Brewed a Kolsch recently and used WLP029 as I always have, started around 1.048 as I always have, got it down to 1.007 as I always have... it just dawned on me that for this one style and this one yeast; I always come up a few points lower FG than what BS2 is telling me I should get.

BH Eff: 82%
Batch Size: 6.25 G
9 Lbs Pilsner
10 oz Vienna
72g Tettnang @60min
WLP029 with a 1.6L starter on a stirplate
Est OG: 1.047
Est ABV: 4.9
Est Final Gravity: 1.010

Mashed at 150 F for an hour, fly sparge, hit OG 1.048 - 1 point higher than predicted but close enough for me. I ferment cool (60F) with a slow rise toward the end to help it finish up and it always lands on 1.007. I've done this in a kettle on a bayou burner fermented in a glass carboy in a temperature-controlled chest freezer, and on an electric HERMS system fermented in a unitank with glycol keeping temperatures in check. Same thing; 1.007. It's predictable, I'll give it that much. But can I get BS2 to estimate the final gravity more in line with what I am actually seeing? Not sure what I might be missing here - it only happens with this recipe/yeast combination. Can I bump the attenuation in that particular yeast profile?
On Tap: Oatmeal Stout, IPA
Fermenting: Air
On Deck: Kolsch

Online Oginme

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Re: Can Estimated Final Gravity be Modified?
« Reply #1 on: October 15, 2019, 01:01:29 PM »
Yes, if you identify that this is happening with this particular yeast strain you can adjust the expected attenuation of that strain.  Open up your yeast profiles, select the yeast you want to change, and then modify the lower and upper attenuation limits for that yeast.  Note that adjusting it in the yeast profiles will not affect any recipes where that yeast is used.  You will need to open up any recipe where you want to change to this newly adjusted yeast and 'substitute' the existing yeast profile for the new one.

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modification