What does the acronym "IBU" stand for in brewing?

The acronym "IBU" stands for International Bitterness Units. This metric is crucial in brewing as it quantifies the bitterness of beer, which primarily comes from hops. The IBU scale helps brewers, judges, and consumers understand the relative bitterness of different beers, facilitating comparisons and selections based on taste preferences.

A higher IBU value indicates a more bitter beer, while a lower value suggests a sweeter or less bitter profile. It's important for brewers to balance IBU levels with other flavors, such as sweetness and malt character, to achieve a well-rounded beer. This measurement is particularly relevant for styles like India Pale Ales (IPAs), where bitterness is a defining characteristic.

The other options do not accurately reflect established terminology in brewing, as the terms related to cellular count (brewhouse, bready, or beverage) do not exist within this context.