IBUs have been up and coming in the beer world for some time now, especially around craft beer. They are now typically found on menus alongside ABVs and many breweries -including ourselves- are putting them on their cans and bottles.
But what do they mean? Interpreting these numbers could probably help you decide which beer you want out of the two, three or four you’ve narrowed the list down to. It can also make you seem like a beer aficionado to your friends as many people are still yet to sweep aside the cloudy mist surrounding these strange ratings. So let's delve into it, shall we?
IBU stands for International Bitterness Units. It is a measurement made by brewers of the isomerized alpha acids (bittering chemicals) found in your beer; these are the things that make it taste bitter, and these alpha acids mainly come from the hops. This precise chemical measurement matches up extremely well with how bitter your beer actually tastes to your brain and this is why people are putting it on their labels. The scale goes from 5 (least bitter) up to 120 (most bitter) but this is not set in stone and in theory there is no end to the scale; however, after about 110-120 IBU we mere humans can’t perceive any noticeable differences anymore.
The measurement of IBUs was first invented, or used, as a quality control tool for brewers so that they could make sure that every batch of beer they produced was exactly the same as the last one i.e. a consistent product. It is only recently that they have found their way out of the laboratory and into the public sphere for the consumer to use.
Wrong. Now we’ve explained to you what IBUs are we’re quite sure you can work out that IBUs are not a rating system for how good your beer is. You can head over to Beer Advocate for that sort of information.
We hope we’ve swept aside the mist that was clouding IBUs. When comparing beers of the same style IBUs can be very useful however they don’t indicate how great the beer is or, necessarily, how it will taste, but they will tell you approximately how “hoppy” or bitter a beer might be. Think of them as actual measurements of bitterness in the beer and a solid piece of information on the side of your beer alongside ABV and the scrumptious sounding brewers tasting notes.
Where it gets tricky with IBUs is that not all beer is made the same, that being that you have stouts and ales and pilsners and sours and so on and so forth. The IBU scale is set the same for all beers, however different malt roasts and grains all impart different flavours into your beer that the IBU scale doesn’t account for. So you could find a stout with a higher IBU rating than, let's say, an ale, yet the ale tastes much more bitter than the stout. The IBUs tell you that the stout is bitterer but the ale tastes bitterer, this is the folly of IBUs. They only really work for comparing like for like beer i.e. beers of the same style. IBUs are most useful when looking at IPAs, why? Because these are beers with a larger hop content than most others and in which, most often, bitterness is a forward and desired flavour and where IBU counts can really help point you in the direction of a beer you'll enjoy.