Author Topic: FG estimates in Beersmith  (Read 119 times)

Offline jc24

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FG estimates in Beersmith
« on: November 20, 2017, 03:04:54 PM »
I'm going to brew a Grapefruit IPA on the weekend with my new Grainfather, but was wondering how seriously I should take the FG estimates in Beersmith? I know they were pretty bang on when I was partial mashing, but how much notice should I take of it when brewing all grain? Am I right in thinking the software does not take into consideration mash temp and therefore fermentability of the wort? It's currently saying my FG will be around 1.015 and I'm wanting 1.010 - should I add some dextrose?

Offline Stevie

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Re: FG estimates in Beersmith
« Reply #1 on: November 20, 2017, 03:19:23 PM »
It does account for mash temp to a degree, but it is just an estimate and can’t always be counted on reliably.

Offline pete b

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Re: FG estimates in Beersmith
« Reply #2 on: November 20, 2017, 04:03:54 PM »
You can't take it too seriously but that only means you could be as likely to end up 5 points higher as you are to come in 5 points lower.
If your concerned about ending up not dry enough, in addition to mashing low use a light hand with any crystal/Carmel malts and add a little sugar.
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Offline a10t2

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Re: FG estimates in Beersmith
« Reply #3 on: November 20, 2017, 04:09:09 PM »
I think that any potential error in the estimate is actually because it *does* assume a mash temperature dependency, which you may or may not actually see, within reason. That being the case, I would assume that if your yeast strains haven't changed, you'll see roughly the same results you were before.
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Offline oginme

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Re: FG estimates in Beersmith
« Reply #4 on: November 20, 2017, 05:10:28 PM »
The BeerSmith FG estimations have been pretty close BASED ON MY SYSTEM.  Everyone's process runs a little differently and when I do a BIAB batch vs using my mash tun, I do figure I will end up a point or two on the low side versus right on or a point high with wort made with my mash tun.

Until you actually do a couple of brews and figure out where the prediction falls in relation to your process and fermenting practices.


Offline BrewBama

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FG estimates in Beersmith
« Reply #5 on: November 20, 2017, 05:18:36 PM »
I think that any potential error in the estimate is actually because it *does* assume a mash temperature dependency, which you may or may not actually see, within reason. That being the case, I would assume that if your yeast strains haven't changed, you'll see roughly the same results you were before.

+1. BS lists % attenuation but I reference the yeast spec sheet when anticipating FG. I find I get pretty close to the spec each time.


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Offline Richard

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Re: FG estimates in Beersmith
« Reply #6 on: November 20, 2017, 10:45:17 PM »
If you click on Options, then select Advanced in BeerSmith, you will see a section called "Adjust Final Gravity Based on Mash Temperature". The default values are a center mash temperature of 153.5 F and a slope of -1.25%/deg-F. There is also a check box to enable this adjustment or not. These settings work in tandem with the yeast attenuation specs. If they aren't working for you, you can adjust them, but I would caution you to do so only after you have made enough precise measurements on your system with a variety of yeasts and accurately controlled mash temperatures.