[ketch32]

Been brewing in San Diego for over 7 years now, and I am a hophead.  I am primarily an IPA and Pale brewer with an emphasis on the hop administration.  More than ever I have been offended by the subjective nature of IBU claims by breweries.  It has become a marketing byline and I don’t understand it.  Claims of over 100 IBUs and even 1000 IBUs have me perplexed, and as a BJCP competition entrant and educated beer drinker  , I am at a loss when I read such nonsense on a bottle, especially when the experience is something much different than what is being claimed.  Sometimes I think, “If that’s 100+ IBU’s my homebrew must be 1,000,000 IBU’s.”  Lovibonds, ABVs, volumes, etc. are all specific, measurable metrics.  According to the definition of IBUs, the scale tops out at 100.  There are ways to calculate your IBU’s.  Why then is it possible to exceed the scale?  Why can’t the IBU information help me decide what beer I want to buy rather than tricking me into some marketing scheme? Maybe if a brewery claimed an ABV of 5% and I find out it’s 10%, or rather the “man” finds out, there may an issue legally, taxing, etc.  But, I think the reason the fluctuation in the IBU standard is that there is no enforcer, and thus the marketers have used it to their advantage, but again, if it really doesn’t educate me as a buyer, and in fact misleads me, then it no longer holds value and is just a gimmick. I don’t believe in gimmicky beers.  My ramblings are done, but hopefully we all can stand up for standardizing some of these “measurable” claims – to help educate buyers, to help educate brewers, and ultimately, to aid in the substantiation of claims of the brewers’ product.

[liquidbrewing]

I agree.  As far as I understand 100+ IBU's is only achievable with hop extract.  Maybe that's how they make their claims.  Like Stone claims Ruination is 100+.  My Beersmith claims the Pliny clone I made, recipe from Zymurgy, was over 200 IBU's!

I understand what you're getting at.  If I'm paying $15 for a 12 oz beer that claims to have 120 IBU's, you kinda want some back up right??  But if the beers good I drink.  Hop utilization is way over my head.  But malt plays a part, so maybe only the high alcohol beers can claim to have such high IBU's.  The hops need the malt to isomerize, or something like that...or is it the Two Hearted clone talking,    I digress..

[mabrungard]

The saturation limit for alpha acids in wort or water is on the order of 85 ppm and the conversion to iso-alpha acid approachs 90 percent of the alpha acids with an extended boil.  An IBU is equal to 1 ppm iso-alpha acid.  So, the maximum IBUs achievable in beer will never approach the exaggerated claims from some brewers.  IBU models such as Rager and Tinseth don't take into account the saturation limit and they will show increasing IBUs with increasing hop and alpha acid addition.  

That premise that the IBUs can exceed about 90 ppm is not factual and has been entirely proven by brewers that take the time to measure the amount of iso-alpha in their beers via lab methods.  I heard Vinny Cilurzo quote that Pliny has only about 80 ppm on the best of conditions and more typically is around 75 ppm.  That is more than enough evidence that the saturation limits I mention above are true and factual in practice.  

Now that saturation limit for alpha acids and iso alpha acids doesn't mean that a brewer and drinker cannot achieve and percieve greater bittering through higher hop additions.  There are other bittering and flavor compounds beside iso-alpha acids (oxidized beta acids are one).  But their bittering effect and perception are far less than iso-alphas.  I think its safe to say that a brewer can't really bitter a beer too far given this limitation for iso-alpha.  

The standard for measuring bitterness is Quinine.  I'd say that it may be possible to add more bittering to beer via an addition of that compound, but I'm not sure if its useful in beer.  I'm betting that its been tried by someone before, but I haven't heard of it.

As a testament to the limitation of bittering in beers, take the case of Double IPAs.  They are typically more balanced than IPAs even though the bittering levels calculated for those brews are typically astronomic.  The level of malt overwhelms the bittering and lends to a more balanced perception.  A true testament to that is that my wife will drink most Double IPAs, but finds most IPAs too bittered for her tastes.  

A new IBU formula is needed that includes the limitation of iso-alpha saturation.

[hopfenundmalz]

Don't believe everything that your programs spit out.  Martin states it correctly that the saturation limit is not taken into account.  What that limit is can be debated, but it is around 90-100 IBU's.  I have never hear a pro talk about a lab measurement of 120 IBUs.

You can get over 100 IBUs in the wort.  Some of that drops out with the trub.  The saturation limit goes down as the pH drops in fermentation, so more drops out.  Some of that sticks to the yeast (more in flocculant strains) so you lose more.  The end result is that your final beer is much less in the IBU level than what the wort started out as.

[dmtaylor]

I agree with Martin and Jeff.  Based on various things I have read (and I read a LOT), in conjunction with my knowledge as a chemical engineer, I agree that it appears impossible to truly get more than about 90-100 IBUs in a finished beer, for the reasons M & J have cited.  Truth be told, determination of true IBUs requires a laboratory test, and the various IBU formulas out there are only estimates giving a theoretical value.  The various IBU formulas don't take the ~90 IBU limit into account, so that is why you see advertisements for 200 IBU beers, etc.  It is certainly false advertising, but what it does tell you is that they most likely used an unusually large buttload of hops in that particular beer, which for some folks, is all they really want to know anyway.  Right?!

[EHall]

It is your responsibility as a consumer to educate yourself! Brewers aren't the only ones with 'gimmicks' and 'false advertising'... The last thing we need is more regulation.. especially around something so trivial as IBUs...

[tomsawyer]

I think the EPA should get involved.  Those dangerous extra acids people are throwing out with their trub are probably getting into the water supply and affecting the development of young children's taste buds.

[phillamb168]

@tomsawyer I am in absolute agreement with you. We have started a movement in France, "GURHou" - Groupe Unitaire de Résistance au Houblon - http://www.facebook.com/groups/259936794027387/?id=263257673695299

The aim of the group is to educate people about the dangers of hops. Hops are evil!

[hopfenundmalz]

@tomsawyer I am in absolute agreement with you. We have started a movement in France, "GURHou" - Groupe Unitaire de Résistance au Houblon - http://www.facebook.com/groups/259936794027387/?id=263257673695299

The aim of the group is to educate people about the dangers of hops. Hops are evil!

Dr. Charles Bamforth always uses an old English quote about hops being "a vile and pernicious weed".

[ketch32]

Thank you, gentlemen!  A lot of useful information for the brewer who wants to be educated (me).  I, for one, will never claim that my beer is something that it is not.  I think a lot of the people claiming astronomical IBUs just aren't educated on the subject and are jumping on the IBU marketing bandwagon.  I don't believe we have regulations to police bitterness claims.  I would hope honest, educated brewers would self-regulate, as they do with a lot of the ingredients, processes and claims that are used.  If more brewers and consumers know about this, I would think the trend would decrease.  Cheers!

[bonjour]

There are measured IBU's and calculated IBU's.  I have heard of a brewer changing the formulation of a beer because it's measurement wasn't the calculated value he was stating.

I have on occasion stated that the Calculated "IBU's" were xxx, especially when they are over 100.

[ynotbrusum]

But are the calculated IBU's for a lower IBU beer correct in terms of what a lab would measure it at?  For example, trying to be style compliant in formulating a recipe of, say 20 or 30 IBU's?  Or should it be similarly qualified as merely "calculated"?  Finally, how do most programs operate - I.e. Tinseth or Rager?

[bonjour]

Most programs allow both, actually your choice.  Only one functional at a time.

[hopfenundmalz]

This should help you to see how the numbers are calculated.  Garetz too.
http://www.realbeer.com/hops/FAQ.html

On my system Tinseth is accurate to within a couple percent for up to 65 IBU, based on the beers that were measured.

[denny]

But are the calculated IBU's for a lower IBU beer correct in terms of what a lab would measure it at?  For example, trying to be style compliant in formulating a recipe of, say 20 or 30 IBU's?  Or should it be similarly qualified as merely "calculated"?  Finally, how do most programs operate - I.e. Tinseth or Rager?

I use the Tinseth scale.  I had some beers in the 35 IBU range analyzed and the results were almost exactly what Promash predicted.