New IBU model

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Pennine

Landlord.
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I have been having some bitterness level issues since moving from sea level to 1,700m. When I use the old ibu models in beersmith they tend to put my IBU levels significantly higher than what I am subjectively tasting. I usually target 20% higher IBUs to balance out the boiling temp differential between sea level and here which is about 6c

Anyway I was listening to a podcast with a Homebrewer who built his own model with additional variables to adjust for calculating IBUs and some experiments where he sent in his data and the model tracks the actual data well. The whole podcast is well worth a listen and you can read about it on his website.

https://alchemyoverlord.wordpress.com/tag/ibu-model/
https://jphosom.github.io/alchemyov...mph-model/alchemyoverlord-blog-content31.html
Here is the model
https://jphosom.github.io/alchemyoverlord/ibu_SMPH.html
When I use the model and adjust for elevation difference and all the other variables it shows why I have been having IBU issues, I am not using enough.

Its really cool to hear about a Homebrewer collecting the data and then publishing it for free.

https://podcasts.google.com/feed/aH...GEtNWI4Yi00N2RlLThiN2EtZmQwYjk4MmYxYzY1?ep=14
 
So is that on top of what beers smith calculate?

https://beersmith.com/blog/2019/12/08/high-altitude-beer-brewing-and-hop-utilization/
Glad I live less the 100m above sea level, save a fortune on hops, but I suppose you use less power in the boil.
Seems like it per beersmith in a 10l batch 30ibus is 10g of 14% magnum at 60, it's closer to 20g according to this calculator.

There are many other factors besides isomerized alpha acids that affect IBUs if you read the initial page. 30% or so of the IBUs come from these.
 
There are other issues too with the late additions they seem to add more fruity contribution from most hops, I think it's more like a whirlpool addition so I also need to figure out the timing. It's a benefit in a neipa not so much in a pilsner.
 
SMPH model is all I ever use. It isn't so new its about 7 years old but a damn site better than using the older models. I put a post up about it a couple of months ago after there was an article in BYO.
A Modern Method for Calculating IBUs - Brew Your Own
I completely missed that one... Just read through it though. Typical banter although a surprising amount of naysayers.

I am also going to start using it as it has an elevation adjustment and seems like it tracks well with my experience at brewing at high elevations.

He said he would love to collect more data to help, might be worth sending a few samples out at some point.
 
I completely missed that one... Just read through it though. Typical banter although a surprising amount of naysayers.

I am also going to start using it as it has an elevation adjustment and seems like it tracks well with my experience at brewing at high elevations.

He said he would love to collect more data to help, might be worth sending a few samples out at some point.
Makes a big difference to the end result more like I would expect a hop forward beer to taste like. I have been trying to tee up with Monash Brew Lab who have the equipment to measure IBU'S but they are close to the end of term at the moment but still trying to get in there before they change the officers.
 
I just ran a czech pils recipe through the SMPH model and Beersmith's Tinseth. I am up to 100g of czech saaz for a 12l batch and with the SMPH model it only at 36ibus, per Beersmith it is 70 ibus. 100g seems bit high but what the hell I am going to go for it.
 
I just ran a czech pils recipe through the SMPH model and Beersmith's Tinseth. I am up to 100g of czech saaz for a 12l batch and with the SMPH model it only at 36ibus, per Beersmith it is 70 ibus. 100g seems bit high but what the hell I am going to go for it.
My Bohemian Pilsner for a 21 litre batch was 160 g of Saaz 61.24 IBU's on Brewers Friend, can't remember the difference would be similar to yours. SMPH has a 2.5 error to Tinseth's 30.5 error.
 
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