Need help with a calculation - Home Brew Forums
Home Brew Forums > Home Brewing Beer > Beginners Beer Brewing Forum > Need help with a calculation
Cool Brewing Giveaway - Supporting Membership Drive & Discount

Reply
 
Thread Tools
Old 06-03-2009, 05:18 PM   #1
Chips
Recipes 
 
Feb 2009
Hamilton ON
Posts: 85


Well I've searched the forums far and wide but have had a hard time finding a calculator that will help me figure out my total mash volume.

Basically, I'd like to be able to enter the amount of water in my mash tun and the amount of grains. The calculator would then spit out the total volume.

It'd also be nice to know what volume would be left over after I remove the grains (using a BIAB system) but the first calculation is the most important.

Any links or formulas would be greatly appreciated!



 
Reply With Quote
Old 06-03-2009, 05:19 PM   #2
PseudoChef
 
PseudoChef's Avatar
Recipes 
 
Apr 2007
West Chicago 'Burbs, IL
Posts: 3,401
Liked 110 Times on 81 Posts


Here you go!

Green Bay Rackers--Mash Calculators



 
Reply With Quote
Old 06-03-2009, 05:22 PM   #3
springer
 
springer's Avatar
Recipes 
 
Feb 2008
Wappingers falls NY
Posts: 4,727
Liked 24 Times on 22 Posts


I use this one mash it
__________________
'The taxpayer: That's someone who works for the federal government but doesn't have to take the civil service examination.'- Ronald Reagan

 
Reply With Quote
Old 06-03-2009, 06:12 PM   #4
MMW
Recipes 
 
Apr 2009
Longview, TX
Posts: 527
Liked 4 Times on 4 Posts


Quote:
Originally Posted by Chips View Post
Well I've searched the forums far and wide but have had a hard time finding a calculator that will help me figure out my total mash volume.

Basically, I'd like to be able to enter the amount of water in my mash tun and the amount of grains. The calculator would then spit out the total volume.

It'd also be nice to know what volume would be left over after I remove the grains (using a BIAB system) but the first calculation is the most important.

Any links or formulas would be greatly appreciated!
I've been kicking around BiaB recently too, here's how I've been thinking it through (giving it a go this weekend, we'll see how it turns out):

For total volume, you need to figure grain absorption. According to the Aussies I've been reading that's 0.5-0.75 l/kg = 0.5-0.75 l/kg * (1.057 qt/l)*(0.453 kg/lb) = 0.5-0.75*0.48 qt/lb = 0.24-0.36 qt/lb grain absorption.

Now plug your grain weight into the calculator with a mash thickness in that range. This gives a grain + absorbed water volume.

Add your batch size
Add boil off
Add some for trub loss

That's the total volume in your mash.

For total water, figure the water for grain absorption then add the three items above.

From everything I've been reading, the only fixed quantity here is the batch size...everything else is based on experience in your system. Hope that helps, and if anybody notes any flaws with that I'm sure they won't hesitate to point them out

 
Reply With Quote
Old 06-03-2009, 06:18 PM   #5
Zen_Brew
Recipes 
 
May 2009
Seattle
Posts: 1,854
Liked 23 Times on 23 Posts


Most of the brewing softwares will figure that out for you as well. I downloaded the trial version of Beer Smith which seems pretty helpful and the trial version doesn't seem very restricted. Not a bad piece of software for the $20 or so.
__________________
Primary: German Hef, Belgian IPA, Scottish 80, Belgian Dubbel
On Tap: Oatmeal Stout, Vanilla Oatmeal Stout, Belgian Dark Strong, Munich Dunkel, Dunkel Weizen, Oktoberfest, Bock, IPA, Black IPA, English IPA, Pale Ale

Using the mind to look for reality is delusion. Using your senses to look for reality is awareness.

"One time I was so desperate for a beer I snuck into the football stadium and ate the dirt under the bleachers." Homer Simpson

Life, Liberty, and the Pursuit of Hoppiness

 
Reply With Quote
Old 06-03-2009, 08:10 PM   #6
Chips
Recipes 
 
Feb 2009
Hamilton ON
Posts: 85

Alright...so I guess I'm just thinking out loud here, but correct me if you see an error:

I'd like my total post-boil volume to be 23L.
So pre boil will have to be 27L. Plus if I assume 3L lost to 5Kg of grain so my total pre-mash volume will be 30L.

30L water / 5 Kg grain = 6 L/Kg mash thickeness. Using that Green Bay "Can I Mash it" calculator I guess I'll need a pot at least 33L (mine is 40). Looks like it'll work!

Thanks to everyone for their input!

 
Reply With Quote
Old 06-03-2009, 09:07 PM   #7
ajf
Senior Member
HBT_LIFETIMESUPPORTER.png
 
ajf's Avatar
Recipes 
 
Oct 2005
Long Island
Posts: 4,646
Liked 105 Times on 99 Posts


I'd like my total post-boil volume to be 23L.
So pre boil will have to be 27L.
That would be true if you boil off 4L and transfer everything from the kettle to the fermenter, or boil off xL, and leave (4 - x)L in the kettle. 4L seems to be a reasonable amount.

Plus if I assume 3L lost to 5Kg of grain so my total pre-mash volume will be 30L.
I would guesstimate that you would lose 5.2L to grain absorbtion.

30L water / 5 Kg grain = 6 L/Kg mash thickeness.
You don't want to use 6L/Kg for the mash. You need about 2.5 - 5 L/Kg (2.5 is thick, 5 is thin) for the mash, and you need to use the remaining water for sparging. If you mash too thin, you may not get full conversion.

Using that Green Bay "Can I Mash it" calculator I guess I'll need a pot at least 33L (mine is 40). Looks like it'll work!
Yup.

-a.
__________________
There are only 10 types of people in this world. Those that understand binary, and those that don't.

 
Reply With Quote
Old 06-04-2009, 04:53 PM   #8
Chips
Recipes 
 
Feb 2009
Hamilton ON
Posts: 85

Plus if I assume 3L lost to 5Kg of grain so my total pre-mash volume will be 30L.
I would guesstimate that you would lose 5.2L to grain absorbtion.

30L water / 5 Kg grain = 6 L/Kg mash thickeness.
You don't want to use 6L/Kg for the mash. You need about 2.5 - 5 L/Kg (2.5 is thick, 5 is thin) for the mash, and you need to use the remaining water for sparging. If you mash too thin, you may not get full conversion.
[/QUOTE]

Alright since I've never done a full boil before I'll go with 4 L lost to an hour long boil, and 5.2L loss to grain absorption. I think everything should still fit!

I'm going to do a "Brew in a Bag" or BiaB method so while the mash seems ultra thin (and it is) everything apparently works out just fine. Here's an informative post about brewing in a bag:
BIAB

Thanks again for the great feedback!



 
Reply With Quote
Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
IBU calculation help Paulasaurus Beginners Beer Brewing Forum 13 04-09-2009 12:49 PM
IBU calculation help Pharmguy General Beer Discussion 4 01-24-2009 08:53 PM
IBU calculation? bbrim Recipes/Ingredients 2 01-10-2009 05:32 AM
Appropriate calculation of ABV? mrfocus General Techniques 2 11-26-2007 07:37 PM
calculation of s.g OCC General Beer Discussion 5 05-31-2005 02:29 PM


Forum Jump