Converting AHS recipes for batch sparging

[29thfloor]

I'm doing my second all grain recipe from Austin Homebrew and I'm trying to figure out how much water to use for a batch sparge. The instructions it comes with just say to use 5 gallons and fly sparge until I run off 6.25 gallons.

I'm assuming I would just subtract the first runnings volume from 6.25 and use that amount for the sparge? Is grain absorption an issue during the sparge? I was thinking that after the mash the grains will have already taken in all the water they can so so, if anything, it would be a lot less during the sparge.

 

[brew2enjoy]

I would down load brewtarget or the Beersmith free trail and plug in your recipe. It will calculate volumes for you

 

[Yooper]

I'm doing my second all grain recipe from Austin Homebrew and I'm trying to figure out how much water to use for a batch sparge. The instructions it comes with just say to use 5 gallons and fly sparge until I run off 6.25 gallons.

I'm assuming I would just subtract the first runnings volume from 6.25 and use that amount for the sparge? Is grain absorption an issue during the sparge? I was thinking that after the mash the grains will have already taken in all the water they can so so, if anything, it would be a lot less during the sparge.

The grains won't absorb any more liquid, so the easiest thing to do is to measure your first runnings and just use the difference of the amount needed for your boil volume.

You can guestimate the amount by figuring out how much absorption you'll probably have. It's about .12 gallons per pound of grain. So, if you use 10 pounds of grains in the mash, you can figure about 1.2 gallons absorbed in the mash. If you mash in with 4.25 gallons, you should get three gallons out of the first runnings (in this example), and you'll need to sparge with 3.25 gallons to get to 6.25 gallons. But measure it to be certain!

 

[29thfloor]

Awesome thanks

This is a session strength beer so it's only using 8.5 lbs of grain, so if I go with 1.25 qt / lb for the mash that's only 2.65 gallons. If 8.5 lbs absorbs about a gallon the first runnings will only be 1.65 gallons. So I would sparge with 4.6 gallons? I'm guessing I'll need to break that up into two batches?

 

[ajf]

Right,

Two other things to consider:

1. You may lose some of the first runnings to dead space in the MLT.
2. You may want to collect a bit more than 6.25 gallons total to account for dead space in the kettle and trub.

I'd prepare about 1 gallon more sparge water than you think you will need. It's better to have too much than too little. The next brew you should have a better idea how much water you will need (if you take notes).


-a.