Illustration by Alyssa Nassner
The concept of bitterness can be somewhat complicated for beer consumers. It’s essential in the development of a stable beer recipe, and it is the sensation most used to describe hops, a key ingredient in lagers and ales. But consumers still largely favor crisper or sweeter malt-driven selections.
In the 1950s and ’60s, the brewing community banded together to create the International Bitterness Units (IBU) scale. The scale was the solution to an issue brewers had with the hops they were using, where alpha acids were decreasing between harvest and brewing.
“It’s always been a brewer’s reference lab measurement that you can use to check for the consistency of your own flavors inside the brewery,” says Steve Parkes, director of the American Brewers Guild Brewing School and owner of Drop-In Brewing, in Middlebury, Vermont. “As a brewery, you need to hit a number from your process so you can know your efficiencies and your losses during fermentation. You want to be able to nail the number every time.”