Partial Mash Questions

Hello World -

I am going to move from extract to a partial mash this evening. I have been reading about this process for a little over three days now and keep getting deeper and deeper into the black hole of information overload.

My plan is to partial 7#'s of grain and then utilize the remaining in LME.

I have a 5 gallon home depot jug that I have converted into my mash tun.

I am extremely confused about the sparging component (batch / fly / continuous) and exactly how to determine the exact amount of water necessary to sparge with.

My brew kettle is only capable of 3 gallons so I am trying to come up with a solid game plan...

Q1 - How do I determine the volume of water to use for sparging?
Q2 - Am I trying to partial too much grain with the equipment that I am working with?

BrewFrisco said:

Q1 - How do I determine the volume of water to use for sparging?
Q2 - Am I trying to partial too much grain with the equipment that I am working with?

Click to expand...

Q1: Everyone goes about this in a little different way. My personal method is to use a total of 3 quarts of water per pound of grain when I brew. This is divided between the mash and the sparge. I've been mashing thinner lately, so I use 1.5 qr/lb for the mash, and then the other 1.5 qt/lb for the sparge. (I batch sparge).

Q2: I think you are going to have some issues with that much grain and that small of a pot. Using my 3 qt/lb method, I would end up using 21 quarts of water for 7# of grain. That's 5.25 gallons of water, split between mash and sparge. The grain will absorb about 1 gallon of that water, but that would still leave me with about 4 gallons of wort collected from the mash.

Advice from an AG newb: All you're trying to do is create enough wort to work with. You will have to use less water than standard recommendations to come up with just 3gal wort. Most people do a full boil but partial boil is FINE. Consider you will lose about a gallon to the grain. You will figure it out after a couple batches. If you have a little extra wort that is better than not enough.

I would start experimenting with a 2.5g for mash, then 2g for sparge. Hopefully you will produce about 3.25g of wort, losing 1.25 to the grains. You should end up with a little extra wort this way. These numbers are just my best guess. I was not able to find a lot of search data regarding PM/AG partial boil so it's a little experimenting. I have done it twice so far.

I have been doing AG BIAB method, give it a search. If you have a mash tun that can hold all the grain, you could still do full AG using partial boil method. It's not any harder than partial.

Q1 - I'm sure someone will have the 'standard recommended' number for mash water, I hear 1.25Qt/lb. Sparge with as much as you can to get up to volume.
Q2 - I was able to fit 13lb of grain and ~3 gal of water in my 5 gal kettle for my mash. You should be fine. It's super fun, good luck!

Thanks for the advice. I could just reduce my base malt (2-row) down to something like 3# and then 1# special and 1# victory for a total of 5# grain to mash.

Using the 1.5qt/lb method - assuming 1 gallon loss to grain soak - leaves me with 2.75 wort - thus leaving me enough room for the 3.3# LME?

Sound like a good plan?

BrewFrisco said:

Thanks for the advice. I could just reduce my base malt (2-row) down to something like 3# and then 1# special and 1# victory for a total of 5# grain to mash.

Using the 1.5qt/lb method - assuming 1 gallon loss to grain soak - leaves me with 2.75 wort - thus leaving me enough room for the 3.3# LME?

Sound like a good plan?

Click to expand...

Well, I'd add the LME at flame out, or at least near the end of the boil, so you don't really need "room" for the 3.3 pounds of LME for the boil.

I'd do this- use 1.5 quarts of water per pound of grain for your mash. Drain. Measure the runnings you got out. Say you got out 1.5 gallons- then sparge with the amount of water you need to fill your pot without boiling over. You'd batch sparge in this instance, so just add the sparge water that you figured you need, stir well, vorlauf and drain. You will be at your boil volume. Do your boil, adding the hops at the correct times, and then add the LME at the end of the boil.