IBU's

[foxy]

Those who subscribe to BYO may have read this article, A Modern Method for Calculating IBU's, I haven't fully checked out his calculator but I have always suspected that Tinseth may be flawed. As I say I haven't compared the two together but the article is in the section Blog Mirror (on world press)
AlchemyOverlord : experiments in beering

 

[foxy]

So looking at the chart I think my suspicions are confirmed.
My brew for tomorrow an English IPA.

The Tinseth predicted IBU 70 actually comes in at just under 40 IBU

 

[Stu's Brews]

Thanks for sharing @foxy - looks like a really useful site.

The mIBU method is what I use in the GrainFather app (you can choose from a couple of different methods) as it seemed to be the most comprehensive method for accounting for post-boil additions.

I've always been under the impression that Tinseth under-estimated the IBUs though as it effectively assumes 0 IBU contribution from the post-boil additions. Maybe that's just the GrainFather implementation though.

 

[foxy]

Thanks for sharing @foxy - looks like a really useful site.

The mIBU method is what I use in the GrainFather app (you can choose from a couple of different methods) as it seemed to be the most comprehensive method for accounting for post-boil additions.

I've always been under the impression that Tinseth under-estimated the IBUs though as it effectively assumes 0 IBU contribution from the post-boil additions. Maybe that's just the GrainFather implementation though.

I have always thought that the IBU's are under estimated using Tinseth, using BJCP guide lines I think the IBU's are lacking when it comes to formulating a recipe and using which ever program, be it Brewers Friend, Brew Father or Beer Smith. It will be interesting to see if any of the later adopt this new concept.

 

[Agentgonzo]

Listing to a variety of podcasts, home-estimated IBUs (a variety of different formulas) seem to always be over estimating when compared to lab-analysed samples - by a similar amount to what you are seeing.

For me, IBU end up just being "a number". I know that in a pale ale 35 (grainfather/mIBU) is the upper limit for what I like, whether the value of 35 is accurate or not - but at least I have something consistent to work with.

It'll be interesting to see how your new brew turns out.

 

[Stu's Brews]

I did a West Coast IPA a couple of years back that including a fairly significant hop-stand addition. I calculated the IBUs using Tinseth and it came out around 50 but when it was ready to drink it was definitely far more bitter. I re-did the calculations with mIBU and it came out at something like 70-75.

Like @Agentgonzo says, it is essentially just a number that we use to describe a subjective impression so the key thing is consistency. I prefer mIBU as it means I can compare the number of a beer with a hop-stand addition to one without it and believe that it will give me the end result I'm expecting.

 

[Agentgonzo]

It's a shame they don't have a more zoomed in view of the graph above, focusing on the more "normal" IBU range of 20-30 (measured). It's just a mass of dots on top of eachother and hard to read in that range

 

[Sadfield]

Unless one is accurately hitting their predicted pre-boil pH and gravity, utilisation is a bit of a crapshoot anyway.

 

[foxy]

Listing to a variety of podcasts, home-estimated IBUs (a variety of different formulas) seem to always be over estimating when compared to lab-analysed samples - by a similar amount to what you are seeing.

For me, IBU end up just being "a number". I know that in a pale ale 35 (grainfather/mIBU) is the upper limit for what I like, whether the value of 35 is accurate or not - but at least I have something consistent to work with.

It'll be interesting to see how your new brew turns out.

The IPA I am drinking now is 70 IBU ( on Tinseth scale) but I know it isn't even close to that, it is a beer I have been trying to replicate for a couple of years. My trouble was taking notice of the not to style.
I have spoke to the brewer from Holgate Brewery who not only told me which hops he used he gave me the hops he used. Even if I had asked him what the IBU's was it wouldn't have made any difference. Their lab would be able to measure the IBU's, so if he told me 40 IBU's that is what I would have been programming into my recipe using Tinseth. I have brewed it many times and kept the IBU's within the style yet when I have had a pint in the brewpub I can drive for one hour still tasting the bitterness of the beer so even 70 IBU's on the Tinseth scale still isn't quite enough.

It's a shame they don't have a more zoomed in view of the graph above, focusing on the more "normal" IBU range of 20-30 (measured). It's just a mass of dots on top of eachother and hard to read in that range

The mass of dots which are close to each other are at the lower end of the scale, the more the IBU's goes up the further out of whack the other scales drift. For instance 60 IBU on the SMPH scale shows the Rager, Tinseth and mIBU well out with Garetz being the closest.

Unless one is accurately hitting their predicted pre-boil pH and gravity, utilisation is a bit of a crapshoot anyway.

Well hopefully most brewers are, but still all things being equal there is still a big difference.

 

[Sadfield]

The IPA I am drinking now is 70 IBU ( on Tinseth scale) but I know it isn't even close to that, it is a beer I have been trying to replicate for a couple of years. My trouble was taking notice of the not to style.
I have spoke to the brewer from Holgate Brewery who not only told me which hops he used he gave me the hops he used. Even if I had asked him what the IBU's was it wouldn't have made any difference. Their lab would be able to measure the IBU's, so if he told me 40 IBU's that is what I would have been programming into my recipe using Tinseth. I have brewed it many times and kept the IBU's within the style yet when I have had a pint in the brewpub I can drive for one hour still tasting the bitterness of the beer so even 70 IBU's on the Tinseth scale still isn't quite enough.


The mass of dots which are close to each other are at the lower end of the scale, the more the IBU's goes up the further out of whack the other scales drift. For instance 60 IBU on the SMPH scale shows the Rager, Tinseth and mIBU well out with Garetz being the closest.


Well hopefully most brewers are, but still all things being equal there is still a big difference.

Different yeast, pitch rate and fermentation will add to the crapshoot.

https://beerandwinejournal.com/bitter-speculation/

 

[JockyBrewer]

Ooh. Good stuff.

I’ve used Tinseth for the past decade (or more accurately, Tinseth in BeerSmith), but the whirlpool/steep calculations are objectively wrong and I’ve relied instead upon empirical methods (aka try it and adjust next time).

Will need to put some of my recipes through that to see how the numbers compare to my impressions.

 

[phildo79]

Those who subscribe to BYO may have read this article, A Modern Method for Calculating IBU's, I haven't fully checked out his calculator but I have always suspected that Tinseth may be flawed. As I say I haven't compared the two together but the article is in the section Blog Mirror (on world press)
AlchemyOverlord : experiments in beering

Seen that. An interesting read and something I would really like to give a try. I have always found it a concern that tinseth and rager can have such huge differences on Brewer's Friend. I would like to see this new calculator added to BF so that I don't actually have to engage my brain to work the IBUs out.

 

[Brewnaldo]

I have often felt the Brewfather predicts more IBU than I end up getting. In fact I think I posted recntly that I was going to start attempting to compensate for this by increasing my hops to push the IBUs of Brewfather up into the 30s for a lager.

 

[DocAnna]

An interesting chart on the calculations, what I wonder about is now is how closely the objective measured values of IBU match the subjective perception of IBU by those drinking beer. This is because our subjective alignment of reported IBU to taste is aligned with Tinseth, as opposed to the subjective taste of a professional laboratory assessor who's taste is aligned in scale to measured values. This makes me wonder whether the BJCP guidelines for IBU are aligned with the Tinseth calculated and perceptually aligned value, or the measured value. If the former, then even though the BJCP IBU guidelines wouldn't match their scientifically measured values, the Tinseth model should still be used.

I hope that makes sense?

 

[Stu's Brews]

An interesting chart on the calculations, what I wonder about is now is how closely the objective measured values of IBU match the subjective perception of IBU by those drinking beer. This is because our subjective alignment of reported IBU to taste is aligned with Tinseth, as opposed to the subjective taste of a professional laboratory assessor who's taste is aligned in scale to measured values. This makes me wonder whether the BJCP guidelines for IBU are aligned with the Tinseth calculated and perceptually aligned value, or the measured value. If the former, then even though the BJCP IBU guidelines wouldn't match their scientifically measured values, the Tinseth model should still be used.

I hope that makes sense?

I'm assuming that you say 'our subjective alignment of reported IBU taste is aligned with Tinseth' is because it is the most common calculation method? As mentioned earlier, I've found that to my taste mIBU is subjectively more accurate when using large hop-stand additions as Tinseth doesn't really account for the bitterness they provide.

When brewing your own beers you can make your own subjective correlation to whatever calculation you prefer to use provided you are consistent with it.

The challenge comes with trying to compare your beer versus someone else's (commercial or home-brewed) as without knowing what calculation method has been used you won't be able to correctly correlate it to your subjective expectations. For example, the same beer can be 50IBU Tinseth and 70IBU mIBU, which obviously you'd expect to taste quite differently if they were just presented as a number with no context.

 

[phildo79]

FWIW, I have contacted several breweries in the past to enquire about clone recipes that they have willingly provided online. I always ask which IBU measuring tool they use and they have always said Tinseth. So if it is a clone beer you are making, I doubt there is much need to deviate from Tinseth as that seems to be the popular choice.

Although I would quite like to design a beer from scratch and use this new measuring tool to calculate the appropriate IBUs depending on style. Would be an interesting experiment.

 

[Clint]

I really will not venture into this...but isn't there a point when bitterness becomes theoretical as we cannot determine bitterness above a certain level?

 

[foxy]

Different yeast, pitch rate and fermentation will add to the crapshoot.

https://beerandwinejournal.com/bitter-speculation/

With a logical approach it means it is the same for whichever measurement also the author noted that hops from the same batch can have different AA.
So concluding that I would prefer to align with a scale with the most degree of accuracy.

An interesting chart on the calculations, what I wonder about is now is how closely the objective measured values of IBU match the subjective perception of IBU by those drinking beer. This is because our subjective alignment of reported IBU to taste is aligned with Tinseth, as opposed to the subjective taste of a professional laboratory assessor who's taste is aligned in scale to measured values. This makes me wonder whether the BJCP guidelines for IBU are aligned with the Tinseth calculated and perceptually aligned value, or the measured value. If the former, then even though the BJCP IBU guidelines wouldn't match their scientifically measured values, the Tinseth model should still be used.

I hope that makes sense?

The guide lines for the BJCP are the actual IBU measured, not from a predictive scale. Some comps ask for the ABV to be on the bottle, never the IBU I suspect the reason being the huge discrepancy in home brew measurements.

FWIW, I have contacted several breweries in the past to enquire about clone recipes that they have willingly provided online. I always ask which IBU measuring tool they use and they have always said Tinseth. So if it is a clone beer you are making, I doubt there is much need to deviate from Tinseth as that seems to be the popular choice.
Although I would quite like to design a beer from scratch and use this new measuring tool to calculate the appropriate IBUs depending on style. Would be an interesting experiment.

I think phildo they are pulling your plonker, breweries, even small ones measure the actual IBU they don't go on Brewers Friend to work out the IBU. All the breweries brew for consistency they wouldn't even venture to guess.

 

[WonkyDonkey]

I think it is somewhere around the 90-100 mark where anything after that point is imperceptible to the common man

 

[Brewshed]

This is very interesting. A while ago I posted a recipe for an Amarillo smash that I had made that had turned out very nicely. Someone pointed our that it had a predicted IBU of about 120 (in either Brewfather or Brewsmith, I can't remember which) and so was far too heavily hopped. It was hop forward (as intended) but not unbalanced and was one of the more enjoyable beers I have made. The graph suggests that, being at the higher end of the IBU scale, the predicted value would have overestimated the IBU considerably, which is what my taste buds were telling me.