Author Topic: Can I account for water absorbed by the grain for a brew in a bag method?  (Read 4815 times)

Offline Pixalated

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I am doing my first all-grain brew, and trying to set up a profile. I figured my hourly boil off rate to be 2 gallons, so I entered that in the profile.
But how do I account for water that's going to absorbed by the grain?

Offline Trendmere

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Re: Can I account for water absorbed by the grain for a brew in a bag method?
« Reply #1 on: February 12, 2012, 05:54:52 PM »
I can only reference a article by Dave Louw  in Brew Your On Magazine and I quote.An approximation that has served me well is one pound of grain absorbs one half a quart of  water. I.E. 12lbs of grain will absorb 6 Quarts of water.

Offline Pirate Point Brewer

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Re: Can I account for water absorbed by the grain for a brew in a bag method?
« Reply #2 on: February 21, 2012, 01:46:46 AM »
I am not a Brew In a Bag brewer so I do not have any exact data, however you can very quickly in just a few brews collect enough data to be very close. Below is a field of "Notes" I include with each brew:

Brew Data:
Strike Temp = ___ *F, Mash Start = ___ *F,  Mash End = ___ *F, Mash Avg = ___ *F, Mash Out = ___ *F,
Strike Volume =_.__  gal, Sparge Temp = ___ *F, Sparge  Volume =_.__  gal, Pre-Boil Volume =_.__0 gal,
Absorption =_.__  gal or _.__ ozw/ozg, Pre-Boil Gravity = 1.0__, End Boil Wort Volume =_.__ gal,
Evaporation Loss = _.__  gal, Hop Loss =_.__  gal, Hop Loss Recovery = _.__ gal, Boiled Wort Volume =_.__ gal,
Cooled Wort Volume = _.__ gal, Cooling Shrinkage = _.__ gal, Shrinkage Percent = _.__ %,
Wort Gravity into Fermenter(OG) = 1.0__, Primary = PRI- _, Yeast Use = _, Pitch Date = __/__/__,
Pitch Temp = __ *F, Pitch Time = __:__, Lag Time = __.__ hrs, Secondary = SEC - _, Rack Date =__/__/__,
Gravity into Secondary = 1.0__, Secondary Temp = __*F Bottle/Keg Date = __/__/__,
Final Gravity = 1.0__, Attenuation % = __.__%

Kettle Water = _,__ gal, Treatment =
Strike = _.__  gal, Sparge = _.__  gal
Top Up Water = Sparge -(Kettle-Strike) = _.__ -(_.__ -_.__) =_.__  gal, Treatment =
Brew Notes:

To make it easy for me, I open a New Recipe, select each of my commonly used profiles, then I copy/paste this note field int the Notes. I then save this basic data as my "Default" recipe. Then I just delete it. When I'm ready to make a new beer, I select New Recipe" and all of my Profile choices and "Brew Data" notefield are there ready to use or modify. As I work through each brew I fill in the data and make the simple calculations. Then I can look back and make averages to enter back into BeerSmith.

For Absorption, since I only Batch Sparge, I calculate the total amount of water I put into the Mash Tun (Strike Volume + Sparge Volume) and subtract it from the total Pre-Boil Volume of wort collected. This is the water lost to the Mash and Lauter process. The "dead space" losses were accounted for in your Equipment Profile to ensure you have enough water prepaired to start out. I then subtract the amount left in the tun, "Lauter Tun Deadspace" which is in the equipment profile, from the total amount lost and use the remainder value as the actual amount absorbed. I then convert this to the "Ounces of Water per Ounces of Grain" shown as "ozw/ozg" as used in the "Options", "Adavnced" screen. Note that the top two entries here are for the ozw/ozg for mash tun and ozw/ozg for BIAB. I think, but don't know for sure, that the difference is that by hanging the large bag of grain where the water can escape from all sides, it is drained more efficiently.

By collecting all of this data, I can brew in a repeatable manner and make reasonable choices about extraction efficiency and hopping rates.

I hope this will help you get where you wish to go.

Good Luck,

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