Kelp was dubbed "the new kale" a few years back by chefs, nutritionists and foodies who embraced its oceanic flavors and purported health benefits. Now seaweed is the star ingredient in "Selkie," a beer at the on New Hampshire's seacoast. Its named after a mesmerizing, mythological water creature that — as the story goes — can shed its skin to take human form on land.

For over a decade, brewery owner Joanne Francis fantasized about making a kelp beer. She discovered one in Scotland called "Kelpie" that was made with bladderwrack seaweed — and fell under its spell.

"It was a beautiful beer, so memorable," she reminisces. "I just loved the idea."

But makers back home didn't hear the same siren song. "It fell on deaf ears among a lot of brewers," Francis recalls. Eventually, brewer Matt Gallagher listened and took up the challenge.

"I could only assume the flavor qualities were going to be salty-briny," he remembers, "and the only way I could think to bring some sort of quaffable balance to that profile would be barley malt sweetness."

So along with Charlie Ireland, the brewery's head of experimentation, the team set out to make their first batch of a full-bodied Scottish red seaweed ale. They just needed the kelp.

Enter Michael Chambers, a marine aquaculture specialist at the University of New Hampshire.

"Next thing we knew Matt and Joanne were out at the farm collecting sugar kelp," Chambers says.

UNH's program maintains a floating aquaculture operation in Portsmouth that's used for research and training on how to grow sustainable seafood.

"Right now we're growing sugar kelp, steelhead trout and blue mussels — all in the same floating structure," Chambers says. "The fish are in net pens inside the frame, and along the perimeter outside of the frame we have the sugar kelp and mussels growing — so it's almost like a biological curtain."

The fish eat and then excrete nutrients that are absorbed by the kelp and mussels, he continues, "so it has a cleaning effect on the environment we're growing them in. Plus, we're growing three different types of seafood."

Collecting sugar kelp was "one of the more interesting days of work," Gallagher says. "Most of the time, as a brewer, you're stuck down in the cellar doing your brewer things."

He and Francis brought 60 pounds of sugar kelp back to the brewery. They rinsed away epiphytes, including tiny crustaceans that grow on the surface of sea plants. Then into the boil it went.

Kelp isn't a new flavor enhancer for brewers. For hundreds of years, coastal farmers in Scotland grew grains in seaweed beds. The terroir imbued the region's beers with hints of sea breeze.

After sipping a freshly poured pint, Gallagher asks, "Do you see this beautiful lacing on the glass?" The tipped beer leaves tiny white lines of foam that evokes a wave-lapped shoreline.

Then he describes the Selkie's bouquet: "When you first get the original nose on the beer, there's something distinctly briny-oceany in there."

What about the taste? (You wouldn't be alone in wondering if Selkie delivers a mouthful of low tide.)

"As I take my sip — and it crosses over my palate — I'm getting a full rush of barley malt sweetness," Gallegher describes. "Then, long after you've had your sip, you experience a saltiness clinging to your lips — like when you jump out of the ocean and a while later you can still taste it."

For the brewer, Selkie is an alternative to the now ubiquitous India pale ales. At 4.9 percent alcohol by volume, Francis calls it "a perfect session beer," or a low-alcohol beer that can be drunk over an extended period of time.

As for customer reaction, Gallagher says his favorite comment has been, "There's definitely beer in this beer." A few said they wanted more "kelpiness."

This journey has been more than a nostalgic trip for Francis. "From my perspective, the obvious local ingredient choice is from the ocean," she says.

It represents an exciting opportunity for seaweed growers, too, according to Chambers.

"You can harvest it, dry it, and sell it," he says, "but for making craft beer, this could be a new market for farmers here in New England."

For their second batch of Selkie, brewers doubled the amount to 14 barrels — requiring 120 pounds of seaweed. They also added two more types of seaweed: dulse and alaria.

The team hopes people won't see Selkie as a gimmick in a crowded beer marketplace. They're fully aware that it merges two food world fads — seaweed and craft beer.

"I don't want people to just drink it and say, 'Yup, that's kelp.' I want them to say, 'That's a really nice beer and I can taste the kelp,'" Gallagher says. "Finding that balance is a subtle line to walk."

Francis agrees. "I don't want to fall into that triple-bacon-donut-coffee-beer trap — with unicorn tear," she muses, with a nod to the foodie obsession with rare ingredients.

Andrea Shea is a senior arts and sometimes agriculture reporter at WBUR in Boston. She was a professional brewer back in the '90s and continues to track the industry's evolution.

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