A new flavor is brewing in the world of craft liquors as distillers borrow from the beer world and add hops for an aromatic twist.

Recent products include hopped whiskies such as R5 from Charbay Artisan Distillery & Winery in the Napa Valley and Hopmonster from the Corsair Distillery with operations in Tennessee and Kentucky. In the non-whiskey category, there’s Hophead Vodka from Anchor Distilling Co. in San Francisco and a hopped gin from the New York Distilling Co. There’s even a half-dozen or so hopped hard ciders.

The move, says H. Joseph Ehrmann, who carries several of the hop-flavored liquors at his Elixir bar in San Francisco, is inspired by the desire to stand out. “They’re up against the big boys, the big brands, and they’re trying to make something that’s going to compete and be unique so that people aren’t looking at them as another bourbon or another American single malt.”

It also tracks the boom in India pale ales – the hoppy beers beloved by craft beer enthusiasts – as well as the quest for innovative cocktails.

Industry-wide, there’s been an explosion of flavored spirits in the past few years, especially the many shades of vodka, driven by efforts to attract new customers and expand shelf space. But Christopher Null, who blogs about liquor at Drinkhacker.com, sees the hop-flavored spirits trend as less about growing market share and more about craft distillers getting in “mad scientist” mode, exploring the limits of what’s possible.

Allen Katz, co-founder of New York Distilling, laughs at the mad scientist label, but concedes there’s may be some truth to it. “We’re just trying to have fun. We are trying to be purposefully different, not esoteric.”

Aromatic and assertive, hop-flavored liquors aren’t for everyone, but they play well with people who are interested in the craft distilling scene and in trying new things, says Ehrmann.

“It’s kind of like smoke or spice; you don’t get a huge amount of people who like it right off the bat.”

Anchor Distilling Co. president David King says there are two types of people who like Hophead Vodka, “the really quite serious craft mixologists like it because it’s so unusual and the craft beer guys like it.”

Sales have been steady, with 4,000 9-liter cases sold in the past 18 months, says King. “It’s an acquired taste, but the people that acquire it like it very much.”

Hop-flavored liquors are made in various ways, but the whiskies generally get their flavor by being distilled from consumer-ready, hoppy beers, as opposed to the much cheaper regular whiskey mashes.

Charbay’s R5 Lot No. 3, the current release, is distilled from Bear Republic Brewery’s Racer 5 IPA beer, and it takes 10 gallons of beer to make a gallon of whiskey, which is further reduced by the 3 percent “angel’s share” lost during barrel aging, says Susan Karakasevic, co-owner and general manager of Charbay. The process shows up in the price, around $80 a bottle.