Add extra boil hop utilization when whirlpool hops are also added

[Si-Co Brewing]

Would it be possible to calculate the extra bitterness derived from late addition boil hops when you also add whirlpool hops and leave everything in the wort during the whirlpool?

For example, I recently created a recipe that had a small 60 minute addition and then two large hop additions split evenly between 5 minutes and flameout/whirlpool. When playing with the recipe I realised that bitterness is only calculated for boil hop additions up to the end of the boil, so when I changed all of the hop additions to become whirlpool hops, the bitterness actually went up, even though they would have been in the wort for longer and at a higher temperature with the 60 minute and 5 minute additions.

Would it be possible to calculate the total IBUs for wort made with normal utilisation for boil hop additions up to the end of the boil and then, if whirlpool hops are added, the boil additions continue to add bitterness but at the lower utilisation rate of whirlpool hops.

I know that would probably be quite tricky to work out mathematically and implement practically but it would probably give a more accurate idea of the bitterness of a beer, especially now large late additions are so popular.

 

[Yooper]

It might be really hard to get it to work right- late additions are often added, but some chill at flame out while some chill to 180 and whirlpool, and some use no chill.

I think the quick and easy fix is to adjust the utilization percentage of the late hops, so that it's more customized to your system (ie no chill, fast chill, whirlpool, etc) without affecting others' calculations. What do you think about that way?

 

[Si-Co Brewing]

Thanks, I think that could work. I've only played around with utilisation for whirlpool hops, I've always left it as the default value for boil additions.

Thanks!

 

[Brewer #186349]

this is a interesting subject and a difficult calculation to work out, not sure.... but if (aa per g of hop strain) x time @ boil = ibu ,
then this must be possible to work by doing Ibu tests at decreasing temps from a boil and recording the values and generate a curve which would probably apply to most hop strains.
looking at Ibu results with a singe hop over a period of time in the calculator shows that most of the Ibu/aa comes out in the early minutes of a boil period and decreases over time. Im sure this will be the same at many temps sub 100c
14 g Citra Pellet 12.8 Boil 60 min 17.65
14 g citra Pellet 12.8 Boil 10 min 6.4
14 g Citra Pellet 12.8 Boil 5 min 3.52
I also wonder also how much ibu's come out at a addition at "flameout/whirlpool" , im thinking quite a lot?? especially if you don't chill the wort immediately.
however someone was able to work out the Ibu's at a boil should be able to do the same at lower temps?
as temp decreases the amount of aa released decreases.? i think...
I probably have this wrong in parts as am not an experienced brewer at all, but understanding the processes, I think
otherwise its down to trial and error and experience

 

[Ozarks Mountain Brewery]

it's a very controversial subject so like above we try to make it as customizable as possible because variables can change for each person, hardness of water, chlorine, brewing salts, acid for ph, all can change the perceived bitterness, when I'm done with my recipe I have a negative RA or hardness and no chlorine, my ph is relatively high so the acid I use drops the bitterness out of my water completely and all recipes need twice the bitterness as most people so a 50 IBU to me is the same as a 25 to most that's why it's better to leave it up to the user to customise it to their set up