All-Grain Noob Question

I have a noob question regarding the volume of water collected after the mash and sparge.

Lets talk about a big high gravity beer. Say for example I have 15lbs of grain to mash. I would use about 4.5 gallons of mash water because of the ratio of 1lb of grain to 1.25q water. ok, then 1/2 gallon sparge water for every pound of grain comes to 7.5 gallon sparge water. I understand there is some grain absorption and evaporation in the boil but this seems like I will collect 12 gallon of wort (4.5 gallon mash + 7.5 gallon sparge = 12 gallons). how does this make a 5 gallon batch of beer????? Boil for 3 days strait?? Thanks for any help.

WVBeerBaron said:

I have a noob question regarding the volume of water collected after the mash and sparge.

Lets talk about a big high gravity beer. Say for example I have 15lbs of grain to mash. I would use about 4.5 gallons of mash water because of the ratio of 1lb of grain to 1.25q water. ok, then 1/2 gallon sparge water for every pound of grain comes to 7.5 gallon sparge water. I understand there is some grain absorption and evaporation in the boil but this seems like I will collect 12 gallon of wort (4.5 gallon mash + 7.5 gallon sparge = 12 gallons). how does this make a 5 gallon batch of beer????? Boil for 3 days strait?? Thanks for any help.

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For maximum efficiency, that's exactly what you'd do! HOWEVER, most of us are willing to give up some efficiency and just use enough sparge water to get us to the boil volume.

In your example, you'd mash in with 4.5 gallons of water. Now, because grain does absorb some liquid, out of that mash you'd probably get out 3 gallons of runnings. If you want to end up with 7 gallons to start your boil (and boil down to 5 gallons), you'd use 4 gallons to sparge with. You won't absorb any more liquid during the sparge- once the grain is saturated, you don't "lose" any more to absorption.

The half gallon of sparge water per pound grain is a general rule of thumb but when you are doing a big beer like this, that may not hold up to the general rule of thumb as you are out of the general beers too.

Anyways, my method is this.

I sparge with 1.25 - 1.5Q per pound.

I record how much I collect during my run off.

Then I determine how much I will need to sparge with to reach my boil volume and divide that in half and do 2 batch sparges.

For example, if I needed 7.5 Gallons of pre-boil goodness and I collected 2.5 gallons after my first run-off, I would need to sparge with 2.5 gallons twice.

Since the first runoff has filled up your dead space and the grain has absorbed most of what it will absorb, what you put in is what you will get out or pretty darn close.


Edit: looks like Yooper beat me to this one

ok, thanks for the help. let me see if i got this right...

i'd mash with 4.5 gallons of water and lets say i get 3 gallons out of the mash, the rest is absorbed by the grain. Then i can add 3 gallons to sparge with. Since the grain is done absorbing water i'll get my 3 gallons of sparge water back and make 6 gallons in total. The average evaporation rate seems to be about 10%. The 6 gallons then becomes 5.4 gallons during the boil because 6 gallons minus 10% over one hour = 5.4 gallons. Bada Bing

Humann_brewing nice avatar...my quote and your avatar are from the same episode. Best Sitcom Ever

+1 on the above advice for fly sparging.

I batch sparge and recently was advised to simply avoid sparging altogether on a large beer (1.100) and I just aimed for 55% efficiency.

It worked out great.

WVBeerBaron said:

ok, thanks for the help. let me see if i got this right...

i'd mash with 4.5 gallons of water and lets say i get 3 gallons out of the mash, the rest is absorbed by the grain. Then i can add 3 gallons to sparge with. Since the grain is done absorbing water i'll get my 3 gallons of sparge water back and make 6 gallons in total. The average evaporation rate seems to be about 10%. The 6 gallons then becomes 5.4 gallons during the boil because 6 gallons minus 10% over one hour = 5.4 gallons. Bada Bing

Humann_brewing nice avatar...my quote and your avatar are from the same episode. Best Sitcom Ever

Click to expand...

Yep, you have got it but don't get your hopes squashed if you don't hit your numbers the first time.

You will need to figure out what you evaporation rate is, it may be more than 10%. Mine is huge since my pot is like 16 inches wide and there is a lot of surface area. I am usually around 7.25 boil to get 5.5 in 60 minutes.

Just make sure to raise the temp up on your sparges but try not to go over 170.


And yes Simpsons are the best.