Doing my first 10 gallon batch, not sure I have the room

[TorMag]

Question: I am doing my first 10 gallon batch. I have a 16 gallon kettle, Beersmith says my total mash with grains will 15.92. That is too close to the top for my comfort level. Thinking of doing a dunk sparge, and I have never done one. Volume of water for the mash is supposed to be 14.12. So the question is how much should I reserve for the Dunk Sparge? Should I take three gallons out of the mash?

Thanks in advance, and Happy Holidays.

 

[doug293cz]

Question: I am doing my first 10 gallon batch. I have a 16 gallon kettle, Beersmith says my total mash with grains will 15.92. That is too close to the top for my comfort level. Thinking of doing a dunk sparge, and I have never done one. Volume of water for the mash is supposed to be 14.12. So the question is how much should I reserve for the Dunk Sparge? Should I take three gallons out of the mash?

Thanks in advance, and Happy Holidays.

I did the same thing a few days ago. I mashed in with 7.75 gal (7.95 @ strike temp) and held back 5 gal for a pour over sparge. Hit my numbers pretty close for a first time process. I didn't want to try to mash in with almost no freeboard. Not sure why you need ~1.5 gal more total water than I did (I netted 11.1 gal to fermenters.)

Brew on

 

[Magnus314]

I've done this a bunch of different ways in my 15.5 gallon kettle. If I'm going to full-on sparge, I'll mash in 10+ and sparge around 4 gallons.

Most times, I'll set aside a gallon or more of strike water in a pitcher or pot or something, mash in, and top the kettle all the way up once everything is stirred in. Then once I pull the bag I'll pour over whatever's left.

Often I find I can fit it all in, even if the math is pretty close.

 

[btbnl]

Before I got my 20G kettle I did this all the time.

If you have a big enough second vessel, and can heat any amount of sparge water, then you'll get the best efficiency by splitting the water equally between mash and sparge.

 

[btbnl]

Not sure why you need ~1.5 gal more total water than I did

Many possible reasons, including different amount of grain, different boil-off rate, different boil duration, or leaving more trub in the kettle.

 

[doug293cz]

Many possible reasons, including different amount of grain, different boil-off rate, different boil duration, or leaving more trub in the kettle.

Quick estimate shows OP's grain bill at about 22.5 lbs vs. my 21 lbs. So, grain absorption difference should be small. Boil off rate should be pretty much the same for a 5.5 gal and 11 gal batch when measured in gal/hr, so OP would have to boil ~ 2X what I did. To boil off twice as much in the same time would require 2X the heat input, or twice the time (i.e. a 2 hr boil). A gallon or more in left in the kettle seems excessive to me. I still think ~1.5 gal more water seems like too much. Maybe it's a little of each of the above, plus maybe more hop absorption.


Brew on

 

[TorMag]

Thanks all. My grain bill is 23.5 and 6 ounces of hops. Beersmith is telling me with my equipment profile and that grain bill I need 14.2

I do have a second kettle 12.5 gallons. That is what I was thinking of using for the dunk sparge.

 

[doug293cz]

Thanks all. My grain bill is 23.5 and 6 ounces of hops. Beersmith is telling me with my equipment profile and that grain bill I need 14.2

I do have a second kettle 12.5 gallons. That is what I was thinking of using for the dunk sparge.

That should work. You'll want to squeeze the bag so that it doesn't hang up on the sides of the smaller kettle during insertion. Tends to drip all over the outside if it does hang up on the sides.

Brew on

 

[TorMag]

One other question, as I have never done a sparge before, what temp is the sparge water supposed to be?

 

[jtratcliff]

Doesn't really matter... I tend to warm mine up near mash out temps so it's faster to boil but I think people have shown that a cold sparge works just fine.

 

[jschein]

Doesn't really matter... I tend to warm mine up near mash out temps so it's faster to boil but I think people have shown that a cold sparge works just fine.

Yup, either way

 

[TexasWine]

One other question, as I have never done a sparge before, what temp is the sparge water supposed to be?

You could keep it simple. Just heat your entire volume of water in your main kettle to strike temp, run some off into the spare kettle for the sparge, and use it at whatever temp it's at when it comes time for the sparge.

 

[btbnl]

With 2 burners and 3 15G keggles I'd do a 10G and 5G batch, heat the sparge water for the 10G batch in with the mash water for the 5G batch while the 10G batch was mashing, and transfer it to the 3rd keggle before mashing the 5G batch.

 

[TorMag]

You could keep it simple. Just heat your entire volume of water in your main kettle to strike temp, run some off into the spare kettle for the sparge, and use it at whatever temp it's at when it comes time for the sparge.

Got it. That makes the most sense.

 

[RM-MN]

Question: I am doing my first 10 gallon batch. I have a 16 gallon kettle, Beersmith says my total mash with grains will 15.92. That is too close to the top for my comfort level. Thinking of doing a dunk sparge, and I have never done one. Volume of water for the mash is supposed to be 14.12. So the question is how much should I reserve for the Dunk Sparge? Should I take three gallons out of the mash?

Thanks in advance, and Happy Holidays.

Beersmith comes with a default set of info that you need to adjust to your system. What kind of efficiency you expect would be the first and that depends on how fine your grain is milled. If you change that to reflect an efficiency that is higher, your quantity of grain will be reduced. With a lower amount of grain less water will be absorbed so that will reduce too. Then you need to input your expected boil off. Beersmith seems to default to about 2 gallons but I tend to boil off less than half a gallon so that would lead to less water too.

If you adjust all those parameters you should find that you have plenty of room for a 10 gallon batch in a 15 gallon pot. If you then reduce the water some more and plan for even a small sparge amount you'll have lots of room.

 

[wilserbrewer]

I tend to be drawn to the easiest and fastest approach. Sometimes I mash in with approx 60% of the total water and begin heating the remainder to around 180 once mashed in. This saves a little time heating a smaller volume prior to mash in.

If my mash temp falls a couple degrees, sometimes I add a gallon of the 180 degree water to bump the temp. When the mash is done, I add the remaining water to the kettle, stir well, wait a few minutes and stir again prior to removing the bag.

I'm not overly concerned with efficiency and find a dunk sparge a PIA especially with larger batches.

Efficiency gained doing a dunk sparge IMO is earned through additional work, personal preference how much work you choose.