B
BeerMonster
Im having trouble making sense of the IBUs calculated by Beersmith for a given boil volume versus recipes from outside of beersmith.
Im making Port O’ Palmer Porter from page 136 of How to Brew 3rd edition, using the extract method plus steeping grain (as per the recipe).
It calls for :
14g Horizon 12% 60 mins 21 IBU
21g Willamette 5% 40 mins 12 IBU
14g Willamette 5% 20 mins 5 IBU.
Total IBU 38.
Putting this into Beersmith with a batch size of 19L and a boil volume of 19L gives 38 IBU. All is well.
But I only have a 10L stockpot. So I change the boil volume to 9L. Beersmith recalculates the IBU to be 21.
I initially think this is realistic as there will be poorer hop utilization with less boil volume. Im just about to up the hop weights by around 100% to get BeerSmith to calculate the final IBU to be 38.
But then I notice the recipe uses a boil volume of 11.4Litres and not 19L. This implies the recipe would give 21 IBU (or thereabouts) despite the book saying it is 38IBU.
So how can Beersmith calculate an IBU of 21 with a boil volume of 9L, yet the recipe calculates 38IBU with a boil volume of 11.4L and gets 38IBU ? Clearly I have entered the initial data correctly since Beersmith agrees with the recipe for the hop quantities used when the boil volume is the same as the batch volume.
One of them has to be wrong, or else Im missing something. 38IBU versus 21IBU is significant in my opinion. Although clearly Im just learning and haven’t really used Beersmith in anger yet – so there’s plenty of scope for a decent explanation and education here.
Colin
Im making Port O’ Palmer Porter from page 136 of How to Brew 3rd edition, using the extract method plus steeping grain (as per the recipe).
It calls for :
14g Horizon 12% 60 mins 21 IBU
21g Willamette 5% 40 mins 12 IBU
14g Willamette 5% 20 mins 5 IBU.
Total IBU 38.
Putting this into Beersmith with a batch size of 19L and a boil volume of 19L gives 38 IBU. All is well.
But I only have a 10L stockpot. So I change the boil volume to 9L. Beersmith recalculates the IBU to be 21.
I initially think this is realistic as there will be poorer hop utilization with less boil volume. Im just about to up the hop weights by around 100% to get BeerSmith to calculate the final IBU to be 38.
But then I notice the recipe uses a boil volume of 11.4Litres and not 19L. This implies the recipe would give 21 IBU (or thereabouts) despite the book saying it is 38IBU.
So how can Beersmith calculate an IBU of 21 with a boil volume of 9L, yet the recipe calculates 38IBU with a boil volume of 11.4L and gets 38IBU ? Clearly I have entered the initial data correctly since Beersmith agrees with the recipe for the hop quantities used when the boil volume is the same as the batch volume.
One of them has to be wrong, or else Im missing something. 38IBU versus 21IBU is significant in my opinion. Although clearly Im just learning and haven’t really used Beersmith in anger yet – so there’s plenty of scope for a decent explanation and education here.
Colin