Developing Our Taste for Macroalgae

Introduction

Seaweed may seem like a recent addition to our diets here in Maine, but around the world using seaweed for food has ancient origins. There is evidence that as early as 14,000 years ago, people living in what is now modern-day Chile were eating seaweed as a regular part of their diets. Additional archaeological evidence from ancient Europe indicates that seaweed was regularly consumed by people ranging from Spain to Scotland as long as 8,000 years ago. Thousands of years later, early written records documenting the use of seaweed in people’s diets were emerging around the world, including in China (600 B.C.E), Japan (600 C.E), the United Kingdom (500 C.E), and Iceland (900 C.E.).

Seaweed has often been depicted in art historically, demonstrating the importance of seaweed in cultures around the world. Pictured above are The Seaweed Gatherers, by Howard Russell Butler and Gathering Seaweed at Omori, by Utagawa Kuniyosshi 

Wild seaweed harvest

For most of history, the seaweed people ate and used came from the wild. Seaweeds need sunlight, nutrients, and a solid substrate to thrive, which means they often live along the shoreline in intertidalAn area of the seashore that is underwater at high tide and out of water at low tide. or shallow subtidalPart of the shore that is always underwater except at extreme low tides. waters. This habitat made seaweed a relatively accessible resource for early coastal civilizations and allowed people to practice wild harvestFood gathered from plants that grow undisturbed in their natural habitat. of seaweeds from the shore or from small boats using various techniques.

From the earliest documentation of seaweed use thousands of years ago right up through the 1950s, wild harvest was the primary method for obtaining seaweed in every part of the world. Even today as seaweed aquaculture is taking off, wild harvest continues to be important and practiced in many places. In the United States and Northern Europe, the wild harvest fishery is particularly relevant and accounts for a large portion of seaweed landings. Here in Maine, a groundbreaking commercial seaweed company, Maine Coast Sea Vegetables, started wild harvesting seaweeds in 1971 and continues to operate today with 100% wild seaweed.

In addition to seaweeds wild harvested for food, Maine has a traditional wild harvest fishery for rockweed (Ascophyllum nodosum), which goes into globally-relevant products like organic fertilizers, soil amendments, biostimulants, and health supplements. This commercial fishery also dates back to the 1970’s, with many founding businesses still active today. In the most recently reported statistics from 2023, wild seaweed still makes up 96 percent of seaweed landings by weight in the state.

A video (3:49) about Maine seaweed harvest featuring Maine Coast Sea Vegetables. Video Credit: America’s Heartland. Available on YouTube: https://www.youtube.com/watch?v=C69TOYVjjpM&t=28s

Justification for eating seaweed

It is no surprise that so many people throughout world history have harvested and eaten seaweed when we consider the many health benefits seaweed provides. Seaweed is essentially nature’s multivitamin! Apart from being delicious and easy to access in many coastal communities, seaweed is also a source of numerous important dietary elements including protein, carbohydrates, fiber, and minerals. In addition, seaweed contains many key nutrients including Vitamins C, B1, B2, B3, B9, B12, A, and E as well as minerals including calcium, iron, potassium and magnesium, and trace minerals like zinc and iodine. Seaweeds contain bioactive compounds not found in land plants – like bioactive pigments (marine carotenoids) that are powerful antioxidants. Due to their unique nutritional profiles, seaweeds have played an important role in food systems around the world, particularly in East Asian nations including in China, Japan, and South Korea where seaweed is a staple food in many diets.

A video (1:45) about the nutritional benefits of eating seaweed. Video Credit: TIME. Available on YouTube: https://www.youtube.com/watch?v=eEwmgJGXGSo

Japanese Sushi Roll

Made with nori (Pyropia spp.), a red algae.

Image credit: Just One Cookbook

Korean Seaweed Soup (Miyeok Guk)

Made with Japanese wakame (Undaria pinnnatifida), a brown algae.

Image credit: Future Dish

Chinese Seaweed Salad

Made with Japanese kelp (Laminaria japonica), a brown algae.

Image credit: Omnivore’s Cookbook

A video (2:43) featuring 10 edible seaweeds, their flavor profiles, and some of their uses. Video Credit: Seaweed-o-pedia. Available on YouTube: https://www.youtube.com/watch?v=M_11lxIY778

So regardless of which coastline you look to, the same story rings true: people eat and use seaweed. The use of seaweed for food has emerged independently in coastal communities around the world, which primarily relied on wild harvest for their seaweed consumption. That is until the 20th century when demand for highly nutritious, inexpensive food met with advances in scientific and technological agriculture; this combination allowed for the development and rapid expansion of commercial seaweed aquaculture beginning in the mid-to-late 1900s.

Image credit: Sobuj et al.

A video (3:59) exploring how to cook with three types of seaweeds commonly used in East Asian cuisines: Nori, Wakame, and Kombu. Video Credit: Yin & Yang Living. Available on YouTube: https://www.youtube.com/watch?v=YB6dcWAH7vQ

A video (11:46) exploring how Maine seaweeds are used in food and beyond, featruing Seraphina Erhart from Maine Coast Sea Vegetables, Rob Dumas from the University of Maine, and Colin Hepburn from Everything Seaweed. Video Credit: Maine Aquaculture Innovation Center. Available on YouTube: https://www.youtube.com/watch?v=0bA_T73OaJ4