A few weeks ago, I wrote about watching for signs of spring in the ocean and the Maine Sea Grant project to track the growth and reproduction in a common intertidal species, rockweed. In the spring, the tips of its fronds swell full of spores that will be released into the water to produce new rockweed colonies.

While these rockweeds are “budding” and “blooming” much like the flowering plants coming up along the coast, they are not plants, but rather are a type of macroalgae. Seaweeds don’t qualify as plants because they don’t have roots or circulatory systems. Instead, they have holdfasts that stick them to rocks or piers and they absorb nutrients directly from the water and the sun throughout their tissues.

These nutrients are not just tasty and nutritious for other marine life like sea urchins and snails, that munch on their fronds, but also for people who either knowingly or unknowingly consume them.

Not too long after I finished graduate school, I had a job at the Scripps Institution of Oceanography and its educational facility, the Stephen Birch Aquarium. There was an exhibit there that looked much like the shelves of a grocery store and was used as part of an activity for school groups that came to the Aquarium for educational programming.

The students had to guess which of the products contained some form of seaweed and it was always funny to see the looks on their faces when they learned that the answers included some of their favorite food items, like ice cream and Cheez Whiz, and that they had likely scrubbed their teeth with seaweed after breakfast that morning.

Carrageenan, a food additive derived from seaweed, is commonly used in food to help emulsify it (keep it mixed) or to thicken it. Salad dressing, for instance, often separates into oil and vinegar, but not if you add a bit of carrageenan. It either emulsifies or thickens ice cream, processed cheese – and toothpaste.


Aside from helping to mix and thicken food products, seaweed is also good to eat in simpler preparations. Rather than using seaweed in a salad dressing, you can have a salad made of seaweed, for example. You would be correct in thinking that rockweed probably won’t make a very tasty salad. But it is just one of many different types of macroalgae that are edible and are native to the Maine coast.

Other brown algae (of which rockweed is one type) include a variety of kelps, which can be dried and eaten as a snack, used to flavor a broth, or eaten raw when fresh. Red algae like dulse, Irish moss, and laver, can be crisped up into crunchy snacks or ground up to make a pudding. Delicate green algae like sea lettuce are perfect in a seaweed salad.

Maine Sea Grant produced a simple guide to edible Maine seaweeds several years ago that you can find at seagrant.umaine.edu/maine-seafood-guide/seaweed. All of these species are high in vitamins, essential amino acids like omegas (which they give the fish that eat them) and antioxidants.

In recent years, seaweed has joined other species like mussels, oysters, and clams in the suite of local species that are being farmed in Maine waters. There are myriad benefits to this including improving the oxygen levels in the water and reducing the Carbon Dioxide levels, thereby reducing the acidity of the water, which is a problem for shelled marine life.

For that reason, seaweeds are even sometimes grown among or nearby shellfish farms. The most commonly farmed species include sugar kelp, skinny kelp, and winged kelp (Alaria). Maine has over 30 seaweed farms along the coast and the industry continues to grow.

In celebration of the environmental and health benefits of seaweed, several groups have come together to organize the third annual Seaweed Week, which began April 22 and continues through May 1. There are multiple components to the event including demonstrations of how to prepare seaweed, workshops on how to identify seaweeds, and tasting events at many restaurants along the coast.


There are two events nearby in Brunswick at ZaoZe Café – Atlantic Sea Farm’s Bri Warner will present a Science Cafe Talk and Zao Ze’s Chef Cara Stadler will host a class on cooking with seaweed followed by dinner. The event’s sponsor, Heritage Seaweeds, is a brick-and-mortar shop on India Street in Portland that sells a variety of seaweed products including cookbooks, field guides, and skin care products, along with many edible products.

On the event’s website (seaweedweek.org), you can find a calendar of all of the events along with a list of restaurants serving seaweed dishes, producers where you can purchase seaweed directly, local businesses featuring products like seaweed beer, cheeses, chocolates, and breads, and an impressive of list of seaweed recipes to try at home.

These include simple ideas like tossing one of Atlantic Sea Farm’s kelp cubes into your smoothie instead of kale or spinach to complex recipes like Zuppa Toscana, a tuscan soup flavored with kelp-infused broth. One favorite seaweed recipe in my house is seaweed pesto, made with kelp cubes, basil, parmesan, olive oil, and sea salt.

Seaweed Week is a way to explore the many ways that the coast and its waters help sustain us and to find new ways to taste some of its benefits. And, if you miss the events this week, there are plenty of products featuring Maine seaweed like kelp noodles, crunchy snack bars, seaweed seasonings, and an assortment of pickled and dried seaweeds, to be found at local stores. Or you can collect your own sampling along the shore and try a few preparations at home.

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