© 2021 Maine Public
Play Live Radio
Next Up:
Available On Air Stations
Business and Economy

Seaweed Beer: Harvesting Maine's Oceans for a Speciality Brew

David Carlson

Brewmasters in Maine have a long track record of using some of the state's signature fruits and shellfish to make specialty beers - think oyster stouts, and blueberry and cranberry ales. Until now, though, no brewer has tried to make beer with seaweed. Fishermen have harvested wild seaweed on the Maine coast for more than 40 years, but only recently began farming it. Next month, a brewery on the Mid-coast hopes to begin pouring mugs of Scotch ale made with farmed sugar kelp.

New beers at Marshall Wharf Brewing Company begin their journey into draft lines and pint glasses inside two large tanks on the Belfast waterfront. The first part of the brewing process is a bit like making a huge cup of tea.

"What we've done so far is that we've 'mashed in' the beer, meaning that we've steeped the grains for about an hour," says brewery owner David Carlson, as he prepares to add a special ingredient to this brew, boiling away in one of his  tanks.

He dips his hand into a plastic bag and pulls out a flaky, brown substance. "During the boil, we're going to go at 20 minutes for half of the addition. At 40 minutes, we'll do the second addition," he says. "Through the whole process, just over 6 pounds of dried sugar kelp is going to go into this whole mess."

Credit Jay Field
Sea Belt Scotch ale in the fermenter at Marshall Wharf Brewing Company.

Marshall Wharf is known for making well-regarded, high-octane beers. This new one, a Scotch ale brewed with sugar kelp,  is called Sea Belt. It's an experiment six years in the making that started when Carlson got turned on to another seaweed beer - an ale from Scotland called Kelpie. "If there's seaweed in Maine that's a good product, why not try putting it in the beer?" Carlson says.

Carlson brought the idea to Jared Mahrunic, a wiry brewmaster of Zen-like focus and few words.

"Jared's very mathematically and chemically and scientifically inclined," Carlson says. "And when I first approached him about it, I kind of got the feeling that it wasn't anything that - well, basically, it boils down to: 'Why mess with what we're doing already?'"

There are people who are willing to help us, Carslon told Jared. Scientists like Sarah Redmond.

"So I work for Maine Sea Grant as a marine extension agent," Redmond says, "and I've been helping these new sea farmers figure out how to grow this seaweed."

There's a $6 billion market for sea vegetables worldwide. Redmond says Maine has had a wild fishery for years. But only recently has the state started to get serious about farming seaweed.

"We know that if we can figure out how to farm it on sea farms, then we'll be able to provide more of a sustainable source of seaweeds for exciting new products in Maine," she says, "and to drive new innovation, new products and new businesses."

On many days, Redmond can be found inside the seaweed nursery at the Center for Cooperative Aquaculture Research in Franklin. There, she teaches fledgling sea farmers, like Peter Arnold, how to seed kelp and other species to be grown on lines.

"The one that we've been raising is sugar kelp," Arnold says. "And we're planning on raising dulse and Alaria and Gracilaria. So our hope is to have a fresh seaweed available, every season, all through the year."

Arnold runs Maine Fresh Sea Farms, a six-month-old start-up. His business partner sells mussels to Marshall Wharf and told Carlson about the sugar kelp they were growing in the Damariscotta River in Bristol. "To have David call up and say, 'I want some for the beer!' was so exciting," Arnold says.

Kelp in hand, Carlson turned to Sarah Redmond for advice.

"You provided us with a glut of information about what we would be able to get out of the seaweed," Carlson tells her. "And that's the most important thing for us, because when you build a recipe, you want to know everything that's going into it. You don't want to fly blind. We knew we were going to get some salt. We'd get some iodine."

Inside the brewery, Carslon and Redmond grab handfuls of kelp. "Jump right up. There's a little platform there you can stand on," Carlson says. "Don't stick you head right in it cause you might get a blast of steam coming out."

It's time. Jared, the brewmaster, stands outside, watching through the window. "All this has to go in," Carlson says. "There's nothing pretty about it. Just grab and toss."

The brittle strips of seaweed disappear into the steam. One question no one can answer yet is exactly what Sea Belt Scotch ale will taste like. "We're taking a risk," Carlson acknowledges. "But at the same time, I want to be on the front line and say, 'Hey, guess what, we made it.'"

If all goes well, Marshall Wharf Brewing Company hopes to begin pouring the state's first seaweed beer in mid to late July.