Ray Isle (@islewine on Twitter) is Food & Wine's executive wine editor. We trust his every cork pop and decant – and the man can sniff out a bargain to boot. Take it away, Ray.

It’s possible you may have missed it, but just before Christmas a team of scientists in Seattle managed to determine the absolute configurations of isohumulones in beer!

Relieved, aren’t you? Me too. But no matter what you think, it’s evidence of sorts that people’s curiosity about beer knows no bounds; and in this case, their curiosity about how hops work.

Hops (the female flower of the hop plant) are used both as flavoring and stabilizing agents in beer. They impart bitterness, and also - depending on the hop strain—resinous, piney and/or citrusy and tangy notes (largely by way of those isohumulones, which they produce when the beer is brewed - but enough about that).

Most beers have some hop character; over the years various craft brewers have also been obsessed with pushing the envelope of how hoppy a beer can get. In the wrong hands, this obsession can result in undrinkably bitter haaargh - water that’s simply masquerading as beer, but for a talented brewer it can result in beers that are delicious in large part because of their complete, crazy, in-your-face hoppiness.

The bitterness that comes from hops, by the way, is measured in IBUs, or International Bitterness Units. To give a comparative guide, most domestic lagers (Miller, Bud, etc.) have bitterness level of about 12 to 15 IBUs, Heineken is about 23, Sierra Nevada Pale Ale, about 38 IBUs.

Beyond 100 IBUs or so, people can’t really detect much difference in bitterness levels, so there’s a physiological limit to all this boundary pushing (that didn’t stop the folks at Ontario’s Flying Monkeys Craft Brewery, who last year came up with an Imperial IPA that clocked in at a wince-inducing 2,500 IBUs). For the adventurous, here are a few extremely hoppy beers that also happen to be extremely good.

Lots of Hops - 50 to 70 IBUs

Ballast Point Sculpin IPA
Dogfish Head 60 Minute IPA
Three Floyds Alpha King Pale Ale

Even More Hops - 71 to 90 IBUs

Saint Arnold Endeavour Double IPA
Bell’s Brewery Hopslam
Russian River Brewing Blind Pig IPA

Just Crazy Amounts of Hops - 90+ IBUs

Stone Ruination IPA
Green Flash West Coast IPA
Harpoon Leviathan Imperial IPA

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