IBU - Beersmith vs. Jamil's Brewing Classic Styles

hbrew · March 13, 2012, 4:46pm

I brewed a Munich Helles from “Jamil’s Brewing Classic Styles” which calls for 11 pounds of grain (10# pilsner, .75# munich,.25# melanoidin). His recipes call for 6 gallons left in the boil kettle. The hop addition is 1.1 oz. Hallertau 4.0 % for 60 minutes. He shows this to yield 18.1 IBU.

Plug this into Beersmith and it gives me a value of 13.6 IBU. Most of his other recipes i have brewed were pretty consistent with values from Beersmith but this seems too far off.

Has anyone else had similar experience or are my calculations off?

muddywater_grant · March 13, 2012, 7:00pm

Did you account for the difference in alpha %?

There could be a 1% or more difference in what the book says the hop has and what beersmith have.

And they both could be off. You really should adjust aplha% to what the hop package says.

shadetree · March 13, 2012, 8:13pm

Jamil uses Tinseth for IBU estimates IIRC - which method do your have your Beersmith using?

jlap · March 13, 2012, 8:56pm

I think Jamil uses Rager actually.

shadetree · March 13, 2012, 9:09pm

[quote=“JLap”]I think Jamil uses Rager actually.[/quote]You’re right, haven’t listened to any of his podcasts in a long time, but now I think about it I can hear him saying “Rager”.

cheshire_cat · March 13, 2012, 9:19pm

Yep he uses Rager… Beersmith’s default is Tinseth. When I changed over had to make some adjustments.

hbrew · March 13, 2012, 10:49pm

mudddywater, i used his alpha value for the comparison. I adjusted to 4.3 % when brewed which brought my addition to 1 oz. Does the different between Tinseth and Rager account for the different that i see (13.6 vs, 18.1)
Why are other recipes closer to Jamils vs. Beersmith in IBU?

jlap · March 13, 2012, 11:46pm

Which formula are you using in beersmith? Rager? Tinseth? Rager will give you more IBU’s for 60 min additions than Tinseth so that might be the difference. Tinseth estimates more bitterness for late additions.

If you’re trying to copy his recipe I would just use the quantity x alpha that he uses. Forget what the IBU estimate is. If his other recipes have resulted in an appropriate level of bitterness on your system then you should be fine. I’ve found that I need to increase the bitterness slightly for many of his recipes to get the right balance but that might not be true for the way you brew/your system.