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Step aside, kale, because it’s seaweed’s turn to get the hot, nutritious green. After all, it has an extremely high nutritional value, is a regenerative crop, requires only sunlight and seawater to grow, and is just as versatile – if not more so – than the leafy greens in the typical American produce aisle. That’s why Alanna Kieffer is advocating for this to be the next big step in ocean-to-plate dining in the United States. (Of course, it’s worth noting that seaweed is already a nutritional component in many East Asian countries thousands of years old.)
Kieffer, a marine biologist, manages Oregon seaweed– the nation’s largest land-based operation – in Garibaldi, Oregon, a small coastal fishing village west of Portland that’s better known as the home of Tillamook Creamery than ocean greens. She also founded an education company Changing tides to offer tours and workshops on ocean foraging and marine science. Between the two companies, you could argue that the city deserves to be as synonymous with ocean vegetables as ice cream.
Nutritious and delicious
Seaweed – in all its many forms, from kelp to seaweed boring and everything in between – is essentially a superfood. The red Pacific dulse she helps cultivate contains all the necessary amino acids, is a great source of several vitamins and minerals, including potassium, calcium, iron, vitamins A and C, and contains fiber, iodine and omega-3 fatty acids. According to Kieffer, it even consists of about 30 percent protein.
[Related: Europeans ate a lot more seaweed 8,000 years ago]
Moreover, it needs very little to bloom. “It really seems like it’s growing on its own,” Kieffer explains. That’s because dulse is a clonal species, meaning it continually fragments and clones itself. It doesn’t even need a solid surface to plant roots in. All it takes is seawater, light and a few simple technologies to aid the process.
No green fingers required
In the case of Pacific dulse, it starts with a few individual plants placed in the twenty 1,500-gallon tanks at Oregon Seaweed, each supplied with nutrient-rich seawater through pipes that extend into the bay. At high tide, a switch on the nearby pier is turned on and water is pumped into the tanks while bubblers circulate the contents, forcing the seaweed into a tumbling motion as it spins from top to bottom again and again. This allows the seaweed to move through the tank, giving each spindly clump of rusty red plants access to sunlight.
The bubbler slows down or speeds up depending on the season, and the dulse is harvested as the tanks fill with up to 400 pounds of seaweed. If so, leave a few plants inside so the process can continue.
The harvested seaweed is then dried in the sun, which requires no energy at all, and is sold fresh or dried for an impressive number of uses and edible options. Other seaweed operations may work slightly differently depending on whether they are on land or in the ocean and what type of seaweed is being grown (kelp is more commonly grown on lines placed in the ocean), but they are all simple and require little if there is there is careful care or intervention.
Durable superfood
That simplicity is part of what makes ocean vegetables such a sustainable crop: Growing seaweed requires no pesticides or fresh water, just sunlight and seawater. And Oregon Seaweed’s operations use a fraction of the energy required for other agricultural products, Kieffer says.
Seaweed is also a powerhouse when it comes to capture and sequester carbon. That’s partly because it’s one of the fastest-growing photosynthetic organisms in the world: some species of seaweed can grow as much as a meter per day, Kieffer says. Although Pacific Dulse is seeing something closer to two to three percent daily growth. And since photosynthesis is the process of capturing carbon, carbon is created seaweed impressively effective when confiscating it.
For example, according to an expert, a single tree could be absorb an average of 22 kg of CO2 per year (depending on age and species), while dulse captures one pound per four adults.
That said, calculating seaweed as a carbon sink is more complicated than studying trees that last hundreds of years, and more research is needed to figure out what happens to that carbon when seaweed is harvested and consumed. When trees die, some of the carbon they have collected returns to the atmosphere as they decompose on the forest floor. What happens when seaweed is harvested is still largely a mystery.
However, some research is being done into afforestation of seaweed, or into creating permanent seaweed gardens that are not intended to be harvested and eaten. Research shows it could be effective in capturing more carbon for the long term.
But the plants also reduce ocean acidification, which can have harmful effects on all aquatic life. Seaweed absorbs the excess nitrogen and carbon that causes this acidification (and often results from agricultural runoff), creating healthier and more balanced ecosystems.
For us, that includes land dwellers, both humans and animals. One study even showed that when seaweed was fed to cows as a small part of their overall diet, aided digestion and reduced methane emissions by an astonishing 80 percent.
Of course, research into the long-term sustainability of seaweed farms is still ongoing. For example, scientists are finding that it should be grown away from seagrass beds so that it doesn’t block light from already established ocean ecosystems. Entanglement can also be a problem – albeit a minor one – for aquatic life in offshore farms. And while responsible farms must stick to endemic plant species that already exist locally, seaweed farming provides many people who fish for a living with an off-season source of income and provides a virtually endless supply of livelihoods and amenities for a growing population. Yes, seaweed is not only used as fertilizer, biofuel, textiles and even as a cat food ingredient, but is also a delicious and versatile ingredient in the kitchen.
Eat up
“I’m obsessed with dulse because of its versatility,” says Kieffer. “It’s a very easy ingredient to put into things.” She calls it the kale of the sea: you can sauté it, roast it in the oven, make a seasoning, pickle it, dehydrate it and much more. Seaweed adds flavor, texture and added nutrients to almost any dish, but it’s just as delicious on its own. Cooked it gives a smoky umami flavor. You can use it in place of anchovies to make a vegetarian Caesar dressing, and ground it can be used as a more nutritious salt alternative.
Add it to the pasta, make a dulse-onion jam or cut a fresh portion and top a few slices of bruschetta with it. The possibilities are virtually endless, as evidenced by not only Oregon Seaweed’s recipe page, but also Winter watersa month-long statewide dining series that Kieffer co-founded to connect Oregon chefs with seaweed distributors, encourage creativity in commercial kitchens and get more seaweed on Americans’ plates.
It’s simply a matter of educating people, she says, showing them how delicious seaweed can be, what a sustainable crop it is, and inspiring people outside places where seaweed is already a staple food to broaden their culinary perspectives.