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Old 07-06-2006, 12:53 AM   #1
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Default Hop Isomerization Rate

My beers have been coming up a bit more bitter than intended. I was wondering if Isomerization could be increased with its temps. Persay I'm boiling my water at 240 degrees, would the hops isomerize faster/more than opposed to 206 degrees?

are there high/low limits to isomerizations rates?

k, thx

EDIT: I just realized water only boils around 200 ish, then it turns into steam. Now I feel dumb

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Old 07-06-2006, 01:40 AM   #2
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When in the boil are you adding the hops? How fast do you cool your wort? What is the carbonation level of the finnished beer?


A lot
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Old 07-06-2006, 02:33 AM   #3
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Originally Posted by digdan
My beers have been coming up a bit more bitter than intended.
Every brewery is different in the hop utilization that it will give you. You have to brew a few batches to figure this out and ad just your recipes accordingly. I have the same problem and if I want to brew a recipe that calls for 40 IBUs, I will aim for 35 IBUs to get the desired bitterness.

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Old 07-06-2006, 01:16 PM   #4
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Isomerization is non-linear: Utilization You get more bittering per unit time early in the boil than later. The best way to control your bittering is to calculate based on AA % rather than weight and add a efficiency factor, which can only be learned by experience. Try aiming for 85% of the bittering on your next batch and see how that works. Since bittering utilization changes more slowly the longer you boil, trying to control the IBU by timing is tough. Adjusting the amount of hops is much easier.

I suspect the non-lineararity is due to the smaller grains of resin being consumed early in the boil.
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