Brewtarget accuracy?

[jeppenedved]

Hi!
I started putting together a recipe in Brewtarget 2.3.0 and noticed that the IBU increased quite fast. So, I put in the recipe of Brewdog Punk IPA to have something to compare with and the IBU ended up at around 200, instead of the 40 it should have. I had to guess the boiling time for the hops but even if I changed timings until it didn’t make any sense at all, the IBU was still way to high. I have checked the units and they are correct. Anyone who has the same experience? And knows if it can be sorted somehow?

 

[pricelessbrewing]

Brewtarget uses a slight modification of the original tinseth IBU formula (same modification as beersmith, and brewersfriend). Instead of the average boil gravity being used, it's the final boil gravity.

Other than that, you should end up with the same IBUs for any boil addition.

Right now, pretty much all software is making different modifications to how flameout/whirlpool/hop stand additions are being calculated.

Can you share the recipe? i can take a look at brewtarget 2.3.0 and the latest developer version to see if there have been any changes/patches.

 

[jeppenedved]

Thanks for your reply! Here is a print screen on the hops. The malt that was specified in the recipe wasn't available in Brewtarget so I had to add it myself (Extra pale 4,38 kg, Caramalt 0,25 kg), which I guess is the reason for the low OG. Although even with correct OG, the Bitterness is still high.

 

[jtratcliff]

Brewtarget uses a slight modification of the original tinseth IBU formula (same modification as beersmith, and brewersfriend). Instead of the average boil gravity being used, it's the final boil gravity.

Other than that, you should end up with the same IBUs for any boil addition.

Right now, pretty much all software is making different modifications to how flameout/whirlpool/hop stand additions are being calculated.

Can you share the recipe? i can take a look at brewtarget 2.3.0 and the latest developer version to see if there have been any changes/patches.

Thread Jack: Hey priceless, I'm stoked you're working on BT... I'm a "long time" user of Brew Target... Submitted a bug report or two... And a big fan of your BIAB calculator...

I had trouble with a quick and dirty build of 2.4 under Ubuntu bionic... Any chance of some new .deb files or 2.4 builds in the ppa?

I'm available for debugging under Ubuntu and Mac OSX if you need... I'm usually running at least 2-3 versions of Ubuntu either in VMs or on my personal laptop... And usually the latest MacOS in my work machine...

End thread Jack

I haven't seen anything similar in my usage of Brewtarget...

Post the recipe and I can try on my various versions, too ..

 

[pricelessbrewing]

Thread Jack: Hey priceless, I'm stoked you're working on BT... I'm a "long time" user of Brew Target... Submitted a bug report or two... And a big fan of your BIAB calculator...

Thanks for the words of kindness. Unfortunately I'm not very well versed in c++ or the tools they're using to develop brewtarget. I'm helping out mostly in documentation, testing, and oversight a bit. But really it's not that involved. There's a lot of people submitting bugs, but from what I can tell not a lot of active devs.

I'm focusing on learning some more, then I'll be working on my own fully fledged software (free, web based mostly, at least at first). Some pretty innovate features are planned if I do say so myself!


Back on topic:

I had trouble with a quick and dirty build of 2.4 under Ubuntu bionic... Any chance of some new .deb files or 2.4 builds in the ppa?

I'm available for debugging under Ubuntu and Mac OSX if you need... I'm usually running at least 2-3 versions of Ubuntu either in VMs or on my personal laptop... And usually the latest MacOS in my work machine...

End thread Jack

I haven't seen anything similar in my usage of Brewtarget...

Post the recipe and I can try on my various versions, too ..

I just run windows atm. I need to get around to re organizing the hard drives and run a dual boot setup again but it's probably a couple months away. You'll have to build it from the github repo, https://github.com/Brewtarget/brewtarget , using https://github.com/Brewtarget/brewtarget/wiki/Getting-Started

 

[jeppenedved]

I have uploaded the recipe as a PDF extracted from BT. Some wording is in Swedish (Kokning=Boil, Torrhumling= Dry hop). The original recipe has been taken from Brewdog's website, the second brew in there DYO Dog. I noticed some some values handling IBU that are adjustable in the preferences (See picture attached). Could that have something to do with it?

 

[jeppenedved]

Now I saw the recipe that 37,5 g of Chinook was set to boil for 5 days instead of being dry hopped. That of course makes a huge difference. Still, I get the IBU to 68, instead of 40 but I guess it could be a matter of not having the entire recipe for the original Punk IPA (they are only specifying the hops as bitter, flavour, aromatic or dry hop). So, I guess it all gets down to my sloppiness. Sorry for making a big thing about nothing!