Jump to content

- - - - -

Easy Mash Calculator

  • Please log in to reply
No replies to this topic

#1 zymot


    Comptroller of Small Amounts of Money

  • Patron
  • PipPipPipPipPip
  • 23020 posts
  • LocationMortville

Posted 05 March 2020 - 11:59 AM

My next brew day, I plan giving BIAG a try. Looking on web sites and researching calculators, I found ones that were way too complicated or too simple than I wanted. After some research, I came up with a simple spreadsheet that I like.


[side bar] You can use this for batch sparging as well, but it does not account for heat lost due to the mash tun.





Grain = Total recipe to be mashed

Pre-Boil = Desired volume when the boil starts (or after you first batch sparge)

Grain Temp = Temperature of the grain

Target Temp = Desired mash temperature

Absorption = Input your allowance for water to be absorbed by the mash. Entering zero here is an option.



Qts/Lb = Calculated for an FYI

Strike Volume = Total water required with absorption included

Strike Temp = Calculated temperature of your strike water

Mash Volume = Calculated volume of mash in your mash tun


It is based on John Palmer's latest "How To Brew" book. In the latest version, Palmer accounts for the difference between volume and weight.


Latest formula is:


Tw = ( ( 0.4 / R ) * ( T2 - T1 ) ) - T2


where R = Qts / Lb * 2.055


The previous versions:


Tw = ( ( 0.2 / R ) * ( T2 - T1 ) ) - T2


Where R = Qts / Lb


Palmer changes the numerator from 0.20 to 0.40 and then divides it by 2.055. The update returns a slightly different Strike Temp value. Between temperature reading errors and rounding up I doubt it makes a real world difference, but might as well be as accurate as we can.


The second tab is a chart that calculates mash volume with gran absorption factored in. This is an issue for those of us doing BIAG using a 10 gallon mash tun/boil kettle.

  • 0

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users