Beer ibu what is

By definition, an IBU is a chemical measurement in beer that quantifies the bittering compounds that make your beer taste bitter, specifically polyphenols, isomerized and oxidized alpha acids, and a few others. The bitterness found in beers comes from the addition of hops during the boiling process when brewing. Hops contain alpha acids, which, when boiled, a chemical process occurs called isomerization. Isomerization rearranges the alpha acids to iso-acids, which adds bitterness to the beer.

The IBU is a scale that measures parts per million of isohumulone iso-acids found in a beer. The IBU scale ranges from 0 — or ; it depends on who you ask. There is a lot of disagreement here on the upper end of the scale.

So any IBU reading higher than is useless as it will all taste the same. When brewing beer, the wort or unfermented beer can reach a saturation point, making it impossible to take on additional alpha acids. From here, no amount of hops will change the IBU number. Here are some styles of beer and their typical IBU range:. What usually comes as some surprise is the high IBU count on some of the sweeter beers, not associated with a hoppy bitter flavor, like American Barley Wine.

For those of you not familiar with this beer style, it is known for its malty sweetness with caramel or toffee-like aroma, not bitterness. Perceived bitterness is the bitterness we actually taste.

This is complex as the bitterness level tasted changes by the individual and sweetness. The IBU scale is not based on perceived bitterness but the iso-alpha acids present. In fact, most modern craft breweries describe the style, ABV, and IBUs on their label artwork and designs, along with a few select mouth-wateringly delicious adjectives to wet your whistle. Thirsty yet? Beer, in its modern form, is a beverage meant to satisfy almost all your senses. The aromas are fresh and evocative.

The taste is often complex when you break it down. The carbonation, the temperature, the viscosity…all factors that contribute to a wonderful experience and perception around the product in your hand.

Did you enjoy it? Did you like it? Would you want to do it again? These are the questions that really matter. I wrote a separate article on this very subject for my site a few years ago, which inspired me to get a few industry experts on the record to hear their take in But before we can go any further, I should quickly define what an IBU actually is.

I was able to catch up with him briefly to get the most accurate definition. Full disclosure — this gets really science-y. The IBU correlates well, in most cases, with the sensory bitterness of beer, and this is why brewers use it. You shake it for minutes to ensure good mixing and make sure the bitter components are in the non-polar phase, take a sample of the nonpolar phase which now has the bitter compounds in it and then put it in the spectrophotometer.

The spectrophotometer shines a specific wavelength of light through the sample, in this case, nanometers which is in the UV range , and measures how much light was absorbed. What none of these breweries explicitly state is that the human palate can only distinguish up to around IBUs before it tucks into its shell and retreats down the esophagus. It could be argued that IBUs have become as much a marketing ploy as a tool for understanding beer.

My advice: just try a sample at the right temperature. To the brewer, beer is art, and art cannot be quantified. Treat IBUs like an art critique: a resource for insight and appreciation. But take them with a grain of salt.

After all, beauty is in the eye of the beer-holder. Jump to navigation. Sign-In Create Account. My Cart Account Support. Search form Search. Podcast Livestream Buying Events.