Calculating Grain Absorbtion

Northern Brewer General
1

I just want to check to make sure I’m doing this right:

8.75lbs of grain.
7.5 gallons of water through the mashtun (strike + sparge)
6.16 into the kettle

So, the difference is absorption - 1.34 gallons, or .153 gallons/lb (which seems high compared to what I’ve read)

That’s the way to do it right?

I think I previously calculated it just based on the strike water and i got a slightly lower number (.128 gal/lb).

Further, I did another batch today, same size grain bill but less water (7.125 gal) and my absorption was .128 when I figured it based on total water through the system.

Thoughts?

Thanks!

2

That may not all be due to absorption, how much is left in your mash tun? At the end of the day it’s all considered a loss and needs to be factored in in your water calculations. My losses to absorption and my minimum dead space in my mash tun works out to ~.12 gallons/pound.

3

I like to use JT’s Mashwater3.3.

http://suburb.semo.net/jet1024/beer/sof ... tware.html
4

If you’re losing more than 0.125 gallons per lb of grain I would let your mash sit in the tun for a while after draining and then scoop out the grain and see what’s in the bottom.