When looking at a craft beer menu, you typically see two quantitative numbers; the Alcohol by Volume (ABV) and International Bitterness Unit (IBU).
The ABV is an important tool for both the brewer and consumer. It tells a scientifically proven amount of alcohol in the beer and is very clear to understand. Beer drinkers should always be aware of the percentage of alcohol by volume, so that they can make informed decisions on their alcohol consumption.
The IBU, however, is part of a much more complicated system.
By definition it is a precise parts per million measurement that scientifically checks the isohumulone found in a beer. Isohumulone is a chemical compound found in hops, which contribute to the bitterness of beer.
Originally a quality control tool used by brewers, the IBU helped to determine a more exact bitterness level from batch to batch of the same beer. Unfortunately, along the way it became a customer facing tool and many inherent flaws were overlooked when employing the IBU as a taste descriptor and marketing tactic. Yet still, this number seems to be forced onto nearly every craft beer menu and can be a major deciding factor of what beer a customer orders.
In reality, a well written beer description gives a much better representation of what the customer is actually going to taste.
One of the reasons that the IBU system is flawed is due to perceived bitterness. Some beers will have a much stronger malt backbone and residual sweetness, which affect the way a person is able to detect bitterness. In beers like this, even if the IBUs are technically higher, the person tasting will likely not be able to sense it.
An example of this can be seen in the Beer Judge Certification Program’s (BJCP) accepted IBU range of a typical Pale Ale and Imperial Stout. When tasting these beers, people will frequently comment on the bitterness of a Pale Ale, while refraining from making the same considerations about an Imperial Stout. However, as you can see below, the Imperial Stout can have double to triple the IBUs. Does that mean the Pale Ale tastes less bitter? Not necessarily.
American Pale Ale IBU: 30- 45
Imperial Stout IBU: 50 – 90
How Marketing the IPA Helped Make the IBU Commonplace
In the mid-2000’s brewery marketing teams, specifically in the United States, noticed that the high IBUs of their new American Style IPAs had a direct correlation with increased sales. This eventually led to the idea of creating beers with super high IBUs, to the dismay of many brewers who tend to seek balance in their beers.
As trend-seeking breweries battled it out for their IPA to have the highest IBU in their region, their sales reps began educating and urging bars and restaurants to list IBU on beer menus, alongside the much more frequently found ABV. By the early 2010’s it was more common than not to see IBU listed on a standard craft beer menu.
In the case of the more modern styles of IPA, brewers attempt to make soft and juicy beers using massive amounts of dry-hops. When the hops are added after the boil, in whirlpool or during fermentation and conditioning, the hops do not go through the same process (isomerization) which creates bitterness that can be detected.
In this case the IBUs remain relatively low, however the beers are pungent and full of aggressive aromatics of hops. Some Vietnamese examples that may be known to some readers would be Hoprizon “Storm Eye IPA”, Heart of Darkness “Loose Rivet NEIPA” and Origins Bia “Đa Kao DIPA”.
This popular trend in modern IPAs has again shifted consumer expectations and muddied the understanding of the relationship between hop character and bitterness. Hop character cannot be expressed by bitterness alone. These terms are not interchangeable and when evaluating hoppiness there are aromas and flavors that must be considered.
The way that craft beer marketers used IBUs as a sales crutch was truly misleading and resulted in a global misunderstanding.
So what is the place of IBU now, in modern craft beer?
As a craft beer consumer there is only one number you should pay attention to; the ABV. Tasting beer is a subjective experience. Enjoy the experience, try new things, and come up with your own conclusions on how the beer tastes.