There've been a number of discussions on hop utilization in recent months, and I think there are some things in the works. I want to take this opportunity to illustrate a difference I've run into on a recipe and ask for guidance on which estimates are closer to reality.
I have an IPA recipe with the following key parameters:
* Preboil: 7.5 gallons
* Kettle volume: 6.5 gallons (1 gallon of evaporation loss over a 60 minute boil)
* Fermenter volume: 5.0 gallons (due to leaving 1.5 gallons of hop sludge / trub in the kettle)
* OG target: 1.060
* FG predicted: 1.013
* ABV predicted: 6.09%
* 60 minute boil with various hop additions
I have the same recipe loaded using 2 approaches:
* Kettle volume target of 6.5 gallons @ 80% kettle efficiency
* Fermenter volume target of 5.0 gallons @ 61.5% brewhouse efficiency (= 80% x 5.0 / 6.5)
The OG, FG, and ABV are consistent for both scenarios.
My issue is that the predicted IBUs are significantly different:
* Kettle approach: 72.23 IBUs
* Fermenter approach: 104.55 IBUs
I'm guessing the 72 IBU value is closer to reality. The program still does not seem to handle the kettle losses properly even when loaded in the Equipment Profile.
For what it's worth, when I view the same recipes on the beta site, I get slightly different values for the Fermenter approach, but the Kettle approach is the same. I'm not sure what improvements are on the beta site at this time.
* Kettle approach: 72.23 IBUs (same as above)
* Fermenter approach: 93.92 IBUs
Here are my two recipes if you want to check them out.
https://www.brewersfriend.com/homebrew/recipe/edit/832951
https://www.brewersfriend.com/homebrew/recipe/edit/932254
I would appreciate any direction you can provide. Thanks.
I have an IPA recipe with the following key parameters:
* Preboil: 7.5 gallons
* Kettle volume: 6.5 gallons (1 gallon of evaporation loss over a 60 minute boil)
* Fermenter volume: 5.0 gallons (due to leaving 1.5 gallons of hop sludge / trub in the kettle)
* OG target: 1.060
* FG predicted: 1.013
* ABV predicted: 6.09%
* 60 minute boil with various hop additions
I have the same recipe loaded using 2 approaches:
* Kettle volume target of 6.5 gallons @ 80% kettle efficiency
* Fermenter volume target of 5.0 gallons @ 61.5% brewhouse efficiency (= 80% x 5.0 / 6.5)
The OG, FG, and ABV are consistent for both scenarios.
My issue is that the predicted IBUs are significantly different:
* Kettle approach: 72.23 IBUs
* Fermenter approach: 104.55 IBUs
I'm guessing the 72 IBU value is closer to reality. The program still does not seem to handle the kettle losses properly even when loaded in the Equipment Profile.
For what it's worth, when I view the same recipes on the beta site, I get slightly different values for the Fermenter approach, but the Kettle approach is the same. I'm not sure what improvements are on the beta site at this time.
* Kettle approach: 72.23 IBUs (same as above)
* Fermenter approach: 93.92 IBUs
Here are my two recipes if you want to check them out.
https://www.brewersfriend.com/homebrew/recipe/edit/832951
https://www.brewersfriend.com/homebrew/recipe/edit/932254
I would appreciate any direction you can provide. Thanks.