[ahoffy]

I am planning to brew the CYBI Union Jack recipe. When I put in the
0 min, Cascade and Centennial hops in Beersmith using the whirlpool/steep for 30 minutes. Beersmith adds about 35 IBUs for a total of 105. Do I need to subtract from the 90 min. or 30 min additions. I am just starting to Whirlpool and trying to understand the extra bitterness this adds. Thanks!

[HoosierBrew]

Depends on what temp you do the whirlpool at - you'll extract more noticeable IBUs at hotter temps. Software is slow to catch up to this method of hopping. I say figure these 35 IBUs into your software this time - ie., subtract that number from your bittering additions. If you think it needs more bitterness, adjust up next time. My current method is to steep at 175-170F but not count those theoretical IBUs toward my total, since I don't perceive IBUs as very noticeable at that temp. Takes some <fun> experimenting!

[erockrph]

A) The difference between 70 and 105 IBU to most drinkers' palates will be minimal. Whirlpool IBU's tend to be less harsh than boil IBU's (at least to me), and most drinkers can't perceive an increase in IBU's above the 70-80 range.

B) It's unlikely that you'll hit 100+ IBU's anyways. There is a limit to how much iso-AA will dissolve in wort, plus the yeast will end up pulling some out during fermentation as well. My 400+ calculated IBU IPA measured at 98 IBU's when I sent it for lab analysis.

C) Short of running controlled experiments that are analyzed in a lab, calculating whirlpool utilization at the homebrew level is a total crapshoot. It would not surprise me at all if the BeerSmith estimate is high.

In other words, run with the recipe you have. If something needs to be tweaked, then adjust it on a future brew. If the beer ends up too bitter, make the adjustment in the earliest bittering addition and leave the late hops as-is.

[hopfenundmalz]

Matt Brynildson talks about the FW procedure, he targets half from early additions and half from whirlpool additions IIRC. If one thinks about how a brewery whirlpools, it is just below boiling and does not drop much due to the large volume of wort. As homebrewers we have the option to do what we want. I have been putting half of my whirlpool hops in after flameout, then some more after the 30-45 min stand and a chill to 170F.

You should listen to the first of the FW series, as he really expains the brewing process in detail.

[ahoffy]

Thank you, for the info.