Split boil and hop utlization

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MikeFallopian

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I perform a split boil for my brews due to space/gear restrictions, and the two pots are combined in the fermenter. I have made good beer for years this way, but have a few questions:

- Is it ok to have the first runnings from the wort in one pot and the second runnings in another? Or should they be mixed prior to being added to the kettles?

- Do I need to split the hops across both kettles? Or is it ok to hop only one kettle? I guess what I'm asking is whether or not hopping one pot only affects hop utilization?

EDIT: sorry for the typo in the title...
 

ncbrewer

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Since the maximum IBU's possible is about 100, you can't get any higher than 50 IBU's in your final beer if all the hops go into one kettle. Other than that limitation, you should be able to use the utilization formulas to get the IBU's you want as far as I can see.
 
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MikeFallopian

MikeFallopian

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Since the maximum IBU's possible is about 100, you can't get any higher than 50 IBU's in your final beer if all the hops go into one kettle. Other than that limitation, you should be able to use the utilization formulas to get the IBU's you want as far as I can see.

Could you explain how adding the hops to just one kettle would result in a maximum of 50 IBUs?
 
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MikeFallopian

MikeFallopian

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Since the maximum IBU's possible is about 100, you can't get any higher than 50 IBU's in your final beer if all the hops go into one kettle. Other than that limitation, you should be able to use the utilization formulas to get the IBU's you want as far as I can see.

Could you explain how adding the hops to just one kettle would result in a maximum of 50 IBUs? I was thinking that hopping one kettle then combining the two would still result in the intended IBUs? Or am I thinking about this wrong?
 
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MikeFallopian

MikeFallopian

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Since the maximum IBU's possible is about 100, you can't get any higher than 50 IBU's in your final beer if all the hops go into one kettle. Other than that limitation, you should be able to use the utilization formulas to get the IBU's you want as far as I can see.

Could you explain how adding the hops to just one kettle would result in a maximum of 50 IBUs? I was thinking that hopping one kettle then combining the two would still result in the intended IBUs? Or am I thinking about this all wrong?
 
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MikeFallopian

MikeFallopian

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Since the maximum IBU's possible is about 100, you can't get any higher than 50 IBU's in your final beer if all the hops go into one kettle. Other than that limitation, you should be able to use the utilization formulas to get the IBU's you want as far as I can see.

Could you explain how adding the hops to just one kettle would result in a maximum of 50 IBUs? I was thinking that hopping one kettle then combining the two would still result in the intended IBUs? Or am I thinking about this all wrong?
 

ncbrewer

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Your kettle with hops can get to 100 IBU's. Then you combine the two. Same isomerized acids, but twice the volume, so it's now 50 IBU's.
 
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MikeFallopian

MikeFallopian

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Your kettle with hops can get to 100 IBU's. Then you combine the two. Same isomerized acids, but twice the volume, so it's now 50 IBU's.

Say I formulate a 5 gallon recipe with 40 IBUs. If I split the wort equally between two kettles and hopped one with enough hops to reach 40 IBUs for 5 gallons, will the acids be diluted? Or would I be hopping one kettle to 80 IBUs then diluting it to 40 when combining with the unhopped wort?
 

Yooper

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Say I formulate a 5 gallon recipe with 40 IBUs. If I split the wort equally between two kettles and hopped one with enough hops to reach 40 IBUs for 5 gallons, will the acids be diluted? Or would I be hopping one kettle to 80 IBUs then diluting it to 40 when combining with the unhopped wort?

You'd have to bitter to 80 IBUs- but that is very hard to do. It's said that you can get a maximum of +/- 100 IBUs in wort, but that isn't really always so. Even Pliny the Elder, which calculates out to something like 250+ IBUs, has been tested in a lab and it's actually in the 80's. It would be almost impossible to actually get 80 IBUs in a homebrew concentrated wort.

If you want to do a split boil, that's fine. Just boil as much as you can, and divide the hops and wort as equal as possible. That will give you the best results.

Anytime you take 2.5 gallons of wort and 2.5 gallons of water (or unhopped wort) and add together, you're halving the IBUs.
 
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