Whirlpool IBU Calculations?

[ultravista]

I plan on whirlpooling for 20 to 30 minutes and would like to know how to calculate the bittering contribution of the whirlpool after flameout.

Is a 20 to 30 minute whirlpool like a 20 minute boil addition or?

[ghwren]

Interesting article here http://www.mrmalty.com/late_hopping.php on the benefits of late, knock off, whirlpool, or standing hop additions (or what ever it's being called today.) I might try using a FWH and a standing addition to make up for the lower utilization from first wort.

[maddspoiler]

I believe you can change this setting. On the recipe page in BS2 double click on your hop addition. This brings up an expanded menu for your current hops addition. Now there is a drop down that says use. Change this to steep and put the amount of time your whirlpooling for. Now it should get you close. There are alot of variables here like how fast you cool and what not and Im not quite sure how BS calculates whirlpool additions. Realize these will make a big impact on utilization factors. If you cool fast enough I dont think youll have too much trouble hitting your mark.

[ultravista]

maddspoiler - my options under the Hops > Use drop-down is boil, dry hop, mash, aroma, and first wort.

Steep is not an option.

[maddspoiler]

Yeah I meant Aroma in the drop down. Then below that it says boil/steep ___Min.

So for Whirlpooling I would guess you should use Aroma in the drop down and you would be steeping for ___ min...

[MaltLicker]

............ a standing addition to make up for the lower utilization from first wort.

Most people/things (incl BSmith) assume that FWH adds to bittering extraction slightly.  Logically, that makes sense to me since the hops are there for the entire steeping time, the rise to boiling, and then the full boil time.  My personal experience led me to think, however, that the perception of bittering was less.  I can't measure IBUs, but FWH does seem smoother and I felt several FWH beers came up short on bittering.

If anyone has good links on this aspect of FWH, please post here.  Thx.