Author Topic: Grain Absorption  (Read 1377 times)

Offline flbrewer

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Grain Absorption
« on: January 25, 2015, 05:27:16 PM »
Just sorting out some notes from my first brew and needed some help with grain absorption. Given the below variables;
-10.2 pounds of grain
-4 gallons of strike water
-2.75 gallons of first runnings
-.25 gallons of MT dead space

Secondly, do grain absorption rates change based on grain, strike, etc.




Offline denny

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Re: Grain Absorption
« Reply #1 on: January 25, 2015, 05:55:05 PM »
I find that if I calculate grain absorption at .12 qt./lb. it's pretty darn close.  It does vary a bit with crush and grain type, but not enough to worry about.
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Offline brewday

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Re: Grain Absorption
« Reply #2 on: January 25, 2015, 06:00:01 PM »
+1

I get around 12% also.  Looks like you got ~10% absorption, which is certainly an acceptable number.
Jon Weaver

Offline HoosierBrew

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Re: Grain Absorption
« Reply #3 on: January 25, 2015, 06:00:44 PM »
I find that if I calculate grain absorption at .12 qt./lb. it's pretty darn close.  It does vary a bit with crush and grain type, but not enough to worry about.

.12 is pretty spot on for me,too. At least plenty close enough.
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Offline BrewBama

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Re: Grain Absorption
« Reply #4 on: January 25, 2015, 09:27:36 PM »
I've been getting .14 but I count that as "in the range" of acceptable.
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Offline flbrewer

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Re: Grain Absorption
« Reply #5 on: January 25, 2015, 09:30:03 PM »
How are you getting my absorption at 10%?

Offline brewday

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Re: Grain Absorption
« Reply #6 on: January 25, 2015, 10:32:57 PM »
How are you getting my absorption at 10%?

Absorption Rate (gal/lb)

Strike Water Added - First Runnings Collected - Loss To Tun = Volume Absorbed

4 - 2.75 - 0.25 = 1

Volume Absorbed / Grain Weight = Absorption Rate

1 / 10.2 = .098
« Last Edit: January 26, 2015, 08:09:42 PM by brewday »
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Offline ynotbrusum

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Re: Grain Absorption
« Reply #7 on: January 26, 2015, 06:59:24 PM »
For clarity, the absorption rate being referenced above is in the .12 gallons per pound range, right?  I have always just figured a pint per pound for a horseback estimate.  I have so little dead space as to not be worth calculating that part, but YMMV.  Maybe a half cup to a cup, at most below the pickup tube.
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Offline Wort-H.O.G.

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Re: Grain Absorption
« Reply #8 on: January 26, 2015, 07:04:38 PM »
For clarity, the absorption rate being referenced above is in the .12 gallons per pound range, right?  I have always just figured a pint per pound for a horseback estimate.  I have so little dead space as to not be worth calculating that part, but YMMV.  Maybe a half cup to a cup, at most below the pickup tube.

same here...almost no dead space and that's how i have it configured in beer smith. my absorption is .12gal/lb...so i collect precisely the amount of projected wort every time.
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Offline dmtaylor

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Re: Grain Absorption
« Reply #9 on: January 26, 2015, 07:07:48 PM »
I get 0.10 GALLONS per pound.
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Offline brewday

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Re: Grain Absorption
« Reply #10 on: January 26, 2015, 07:15:49 PM »
Yep, gal/lb
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Offline factory

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Re: Grain Absorption
« Reply #11 on: January 26, 2015, 07:24:50 PM »
I was wondering if my system was freakishly efficient for a minute there.  I actually get .10 gal per pound too. 0.15 gallons left for mash tun deadspace. 

Offline flbrewer

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Re: Grain Absorption
« Reply #12 on: January 26, 2015, 08:16:17 PM »
Thanks gents.