Brewtoad and whirlpool IBUs

[deadwolfbones]

So, Brewtoad doesn't add any IBUs for whirlpool additions.

I made a 2.5gal sessionable SMaSH with Calypso (12.9% AA) with the following hop schedule:

0.25oz at 60
0.25oz at 15
0.25oz at 5
1.5oz whirlpool (15min at 170F)

According to Brewtoad, the estimated IBU was ~43. After 7 days fermenting, it tastes more like 100. Lo and behold, I put the same recipe into Brewer's Friend and got 108, since it assumes 10% utilization from whirlpool hops.

I should note I also gently squeezed the hops that I filtered out transferring to the fermenter.

So, is this just a (known?) shortcoming in Brewtoad, a combination of that and the fact that I squeezed the hops, or something else making it super duper hoppy?

I admit my knowledge of hop utilization from whirlpool additions is basically zero, so I have no real reason to trust Brewtoad over Brewer's Friend (or vice versa) beyond my tastebuds telling me that this beer is waaaaay too bitter.

In the interest of science, I'm brewing a second batch tomorrow (with Idaho 7, instead of Calypso—12.8% vs. 12.9%) and planning to use this hop schedule:

0.25oz at 20
0.25oz at 5
0.70oz whirlpool (15min at 170F)

Brewer's Friend tells me this is ~47 IBU, which is more like what I'm looking for. Is this a good way to go?

 

[ScrewyBrewer]

Using either app, reduce the hop quantities to where you like the level of bittering. Without a lab to measure the actual IBUs, its impossible to say which app's IBU prediction is the closest.

 

[deadwolfbones]

I mean, that works if I don't want to use whirlpool hops, but I do.

If I plug my newer recipe into Brewer's Friend, I get 47 IBU, while Brewtoad gives me 17 IBU. That's a huge difference.

I think ultimately I have to just make a few batches based on different software and see which one comes out closest to my expectations. Right now, Brewtoad isn't anywhere near close, though.

 

[raysmithtx]

I had a similar problem when I altered a known recipe to make it all late addition hops and ended up with a bitter hop bomb. I did a lot of research on the whys and came up with a solution that works for me.

To minimize the problem, use hop bags so you can remove all of the hops at the end of the boil. If you don't (assuming it takes 15 minutes to get down to 170 degrees) then your 60 minute hops become 75 minute hops, the 15 minute hops become 30 minute hops and the 5 minute hops become 20 minute hops. When you put those numbers in and look at the IBU's it will definitely make a huge difference. Having a way to remove all the boiled hops at the exact end of the boil will get the recipe a lot closer to the predicted IBU's, and waiting for the temp to drop below 170 before adding the whirlpool hops will minimize the bitterness from the whirlpool hops.

 

[ScrewyBrewer]

...you can remove all of the hops at the end of the boil. If you don't (assuming it takes 15 minutes to get down to 170 degrees) then your 60 minute hops become 75 minute hops, the 15 minute hops become 30 minute hops and the 5 minute hops become 20 minute hops.

My 10-gallon batches take ~45 minutes to cool to 170F after flameout. For NEIPAs, and a few other styles lately, I only add whirlpool hops to a hop spider at flameout. And the bitterness is just right.

 

[madk]

If you cooled to 170F before your whirlpool, you shouldn't have added any more IBUs as you are below the isomerization temp. As far I know that stops around 175F.

 

[raysmithtx]

If you cooled to 170F before your whirlpool, you shouldn't have added any more IBUs as you are below the isomerization temp. As far I know that stops around 175F.

But if the other hops that were added previously were still in the kettle, they will continue to add bitterness.

Here's some really good information at this link:
https://alchemyoverlord.wordpress.com/2016/03/06/an-analysis-of-sub-boiling-hop-utilization/https://alchemyoverlord.wordpress.com/2016/03/06/an-analysis-of-sub-boiling-hop-utilization/

 

[madk]

But if the other hops that were added previously were still in the kettle, they will continue to add bitterness.

Here's some really good information at this link:
https://alchemyoverlord.wordpress.com/2016/03/06/an-analysis-of-sub-boiling-hop-utilization/https://alchemyoverlord.wordpress.com/2016/03/06/an-analysis-of-sub-boiling-hop-utilization/

Interestingly enough there is an article about IBUs in the latest Zymurgy. Not sure of all the details just yet as I just browsed it, but it talks about 60+ min additions not adding more IBUs.

 

[raysmithtx]

Interestingly enough there is an article about IBUs in the latest Zymurgy. Not sure of all the details just yet as I just browsed it, but it talks about 60+ min additions not adding more IBUs.

I'm just sharing what happened to me when I converted all my hops to late hop additions and ended up with a hop bomb.

Figure 3 in the article shows the IBU's continue to increase during the whirlpool.

 

[ScrewyBrewer]

Interestingly enough there is an article about IBUs in the latest Zymurgy. Not sure of all the details just yet as I just browsed it, but it talks about 60+ min additions not adding more IBUs.

Great article. I dropped Petr an email and he replied with a link to download his spreadsheet mentioned in the article. Once I wrap my head around his formulas I plan to add them to ezRecipe. The whirlpool hop IBU formulas I'm using now are accurate but I'd like to compare them with Petr's.

 

[deadwolfbones]

I had the hop bomb/late addition issue in a previous batch I did, thanks to my lack of any kind of chiller. This time it was due to whirlpool additions. One of these days I'll get a handle on it, probably with a plate chiller. But thanks for the hop bag suggestion; I'll try that for the next IPA I make.

 

[thehaze]

I only use 3% hop utilization for whirlpool on Brewer'sFriend and that seems to work for the system I have. 10% utilization is high, at least for the way I am doing and have seen others do.