Hops A-Z: B is for Bitterness

The right kind of bitterness. Not the kind that we associate with toxic substances, nothing bordering on the taste sensation of denatonium. It's about the bite, the edge, the sudden sharp finish or the lingering itch.

It's all about the alpha acids again. The thermal isomerisation of the humulones produces the intensely-bitter iso-alpha acids; they're modified by the residual sugars present in beer to balance out the bitterness.

But how bitter do you want your beer to be? International Bitterness Units (IBU) provide a guide, with a classic English bitter rating around 25-35 IBUs on a scale where 100 IBUs is regarded as the threshold of taste. Not that such limits hold back extreme beers by experimental brewers - Brewdog, Pitstop and Mikkeller have all sought to produce beers with a theoretical bitterness way in excess of what the palate can discern.

Perhaps that's good PR but bordering on developing a denatonium approach to brewing. As Brooklyn brewmaster Garratt Oliver says, "It’s a fairly idiotic pursuit, like a chef saying, ‘This is the saltiest dish'. Anyone can toss hops in a pot, but can you make it beautiful?”