In his decades-long career in shellfish aquaculture, Carter Newell, founder and managing member of the Pemaquid Mussel Farms cooperative based in Damariscotta, has conducted countless experiments on how to best grow, harvest, grade, sell and cook mussels.

While a marine biology student, he rigged up a test in the kitchen to see where in a pot the mussels get the hottest. The results cemented his standard cooking process for the blue bivalves: Line a pot with sliced onion, garlic and leeks; add 1/4 inch of water or wine; throw in the mussels and clamp on a lid. Once the liquid boils, Newell give the pot a good shake. He brings it back to a boil and gives it a second shake. A third and final boil and shake renders a pot of plump, perfectly cooked mussels, he says.

If you board the Mumbles, the custom-built 60-foot barge Newell and his cooperative colleagues use to move between aquaculture sites, you’ll find specialized mussel-processing equipment from Spain, Holland and Prince Edward Island. Newell has tested and tweaked the imported gear to best suit growing mussels in Maine.

Last summer, he picked up a patent for a submersible raft from which hundreds of thousands of mussels can grow on ropes attached to it in relative peace, protected from wind, waves and ice that can plague mussels that grow attached to traditional floating rafts. Freed from riding the highs and lows of the waves, Newell’s mussels can spend more time feeding, thus growing quickly to harvest size.

Given his experimental nature, it’s no surprise that Newell has a few ideas on how to cut waste from the Maine mussel industry. For example, while working at a mussel processing plant early in his career, he collaborated with a local company to produce an organic soil additive that had as its main ingredient mussels with cracked shells that wouldn’t make the retail grade. And he’s proven that crushed mussel shells planted in piles in the Damariscotta River can be used to collect non-native European oysters as the shells give the young oysters something to hold on to.

When I met him over lunch (we were eating mussels he’d donated to feed conference participants at a Slow Money Maine event in late November), we talked about all the ways spent mussel shells can be repurposed in the home instead of going out with the trash. Exceptionally good-looking shells might make a pretty piece of jewelry or two. A deeply cupped shell can stand in as a spoon in a salt cellar or sugar bowl. And a handful of shells thrown into the bottom of a potted plant makes a biodegradable drainage system. But Newell was thinking slightly bigger: how to make use in one go of all the shells left over from a hearty meal?

En masse, they can be broken up just a bit and piled as mulch around grit-loving plants. Break them up further and spread them around plants to deter slugs. Crush them and throw them to backyard chickens as a calcium supplement or onto the compost pile to break down slowly over time. Actually, Newell argues that burning them in the fireplace is a more efficient way to break mussel shells down into a ready-made garden additive. The protein in the shells give off a nice flame on a small fire, while the calcium carbonate burns into lime-filled ash, a useful soil amendment for any gardener looking to control the pH of his vegetable plot. It’s not lost on Newell that vegetables grown there just may end up in the mussel pot to complete the circle.

CHRISTINE BURNS RUDALEVIGE is a food writer, recipe developer and tester and cooking teacher in Brunswick, and the author of “Green Plate Special,” a cookbook from Islandport based on these columns. She can be contacted at [email protected]

ROASTED MUSSELS WITH SAUSAGE, ONIONS, TOMATOES AND WHITE BEANS

This recipe could easily be made in a Dutch oven on the stove top following mussel farmer Carter Newell’s boil and shake technique for mussel cookery. I roasted them for a change of pace and a thicker sauce.

Serves 4

1/3 pound spicy raw sausage like chorizo, linguica or hot Italian

1 cup chopped onion

1 tablespoon olive oil

2 cups diced canned tomatoes
1/2 cup white wine

1 1/2 cups cooked white beans like great northern or cannellini

3 pounds raw mussels, rinsed and beards removed

1/4 cup chopped fresh parsley

Crusty bread for serving

Heat oven to 425 degrees F.

Chop sausage into 1/2-inch pieces. Scatter sausage and onion around the bottom of a 13 X 9 baking dish. Drizzle with olive oil.

Place pan in oven and roast until sausage is sizzling and slightly browned and onions are softened, 5-7 minutes.

Add the tomatoes and wine to the pan. Stir to combine and return the pan to the oven so that the sauce will heat through and begin to bubble, another 5-7 minutes. Stir in the beans and mussels. Roast until the mussels open wide, 5-7 minutes. Remove the pan from oven, scatter the parsley over the top, and serve with crusty bread, discarding any mussels that failed to open.