All Grain Split Boil Math?

[iBrewBeer]

Hi,
I'm getting ready to do my first all-grain 5 gallon batch and can't do full boils (high rise condo). So, I'm splitting the boil. I think I've got most of the procedures down except how to make sure I collect enough wort to account for the boil off rate in my two kettles (they're exactly the same size and type).

I use BeerSmith but don't see how to set it up to account for split boil evaporation. Anyone know the best way for me to tackle this first AG batch?

Cheers!

 

[Yooper]

Hi,
I'm getting ready to do my first all-grain 5 gallon batch and can't do full boils (high rise condo). So, I'm splitting the boil. I think I've got most of the procedures down except how to make sure I collect enough wort to account for the boil off rate in my two kettles (they're exactly the same size and type).

I use BeerSmith but don't see how to set it up to account for split boil evaporation. Anyone know the best way for me to tackle this first AG batch?

Cheers!

I used to have to do that, too, when I first starter. Your boil off will be twice what it would normally be, but for the first time it's hard to know for sure. If you've ever done an extract batch in that pot, the AG boil off rate will be the same. I'd expect a gallon or so from each pot to start, if you don't know where to begin.

What I liked to do was to make sure the runnings were "equal"- that is, half of the first runnings and half of the second runnings roughly equally divided between the two pots, and then the hopping divided roughly equally also. That helps will making sure your hops utilization is about the same in both pots, and to make sure you actually have the same beer recipe you intended.

 

[iBrewBeer]

That makes sense Yooper. So I'll make up the difference in collecting the second runnings? For example, if the recipe says to sparge with 2 gallons I'd bump it up to 4 gallons?

 

[Yooper]

That makes sense Yooper. So I'll make up the difference in collecting the second runnings? For example, if the recipe says to sparge with 2 gallons I'd bump it up to 4 gallons?

Not necessarily! You'd probably only want to account for an "extra" gallon. When you get a chance, if you post your recipe, and what your typical boil off is in that pot, we can help you come up with a good volume guestimate.

 

[iBrewBeer]

I've read really good reviews of Edwort's Bee Cave Brewery Haus Pale Ale - All Grain recipe. Think that would be a good starter AG batch. The 1 gallon evaporation rate is a good starting point for my kettle(s).

Thanks for helping me nail down these volumes Yooper!

 

[lostboysbrew]

@Yooper isn't another way to just do a concentrated boil and then add top off water at the end???

back in the day when I only had a 20qt and was doing 5 gallon batches, I did about a 3 gallon boil and just topped off at the end. Never had any issues what so ever as long as you either camden tab your top off water, or boil it in another pot.

It might be easier than trying to even out the runnings.....

 

[Yooper]

@Yooper isn't another way to just do a concentrated boil and then add top off water at the end???

back in the day when I only had a 20qt and was doing 5 gallon batches, I did about a 3 gallon boil and just topped off at the end. Never had any issues what so ever as long as you either camden tab your top off water, or boil it in another pot.

It might be easier than trying to even out the runnings.....

There are ways to do that, I'm sure. I'd rather boil more than less, though. A couple of reasons. One, you'll kill your efficiency! No way you can get enough gravity points for a bigger beer with only mashing with 3 gallons and no sparging. For another, you'll kill your IBUs. Not a big deal at all for a beer like a Scottish, but for an IPA, that would be very noticeable. About the max you can get into suspension is 100 IBUs. If you top up with 50% water, you'd half the IBUs.

It would work better if you had a 4.5 gallon boil, and just topped up a gallon or so. But having enough grain for a 5 gallon batch but only drawing 3 gallons of runnings out would mean a lot of wasted grain, and still low efficiency.

 

[iBrewBeer]

Well I just ran another test of my kettle boiling 3 gallons of water and ended up losing about 3/4 gallon after a 60 minute boil. Looks like I'll have to swag it to determine my initial volumes for the first split boil AG batch.......****sigh****