Seaweed Demystified

June 6, 2012

Seaweed Demystified and Ready to Eat!
Editorial by Leanne Haight

Seaweed has been harvested around the world for centuries. But, here in America, it still seems to be a bit of a mystery for many. So, let’s see if we can demystify it and then eat some!
Seaweed is the common name for a wide variety of algae in the oceans, and is generally classified into three categories: Red, brown, and green. There are in the neighborhood of 10,000 different types of seaweed. Kelp is a species of brown seaweed, and there are over 300 different types of kelp. It is no wonder we sometimes feel overwhelmed by which seaweed to use! There are several factors to consider when choosing a seaweed- nutrient values, intended use, location from which it is harvested, and harvesting practices, to name a few. Let’s look at each of these pieces, but first let’s talk about what seaweed is exactly, and how it functions in our food system and our bodies.

Seaweed requires two basic things to flourish: Salt water (at least to a degree) and light for photosynthesis. It does not have a root system; it absorbs nutrients directly through its outside membrane. The different varieties grow at varying depths. Green seaweed grows closest to the surface- often at water’s edge, brown grows at mid-range depths, and red can grow as deep as 200 feet, depending on the clarity of water and the ability of light to penetrate.

Seaweed is a vital base of our marine food system. It is fed on by small animals (periwinkles, limpets, sea urchins, as examples) which in turn are food for the larger fish & animals. Seaweed also provides critical habitat for all of the little ones. Because of its status in the food web, close attention must be paid to harvesting practices- when, where, how much and how often. The seaweed suppliers supported by Azure are vigilant in their sustainable harvesting practices, adhering to strict wild harvesting and even organic guidelines. Those guidelines define where seaweed can/cannot be picked –distance from ports, cities, drainage systems, etc., how close to the base to cut, and what percentage of the bed can be harvested per year. Some Azure suppliers go beyond the organic standards by not using motor boats in or near the bed, hand harvesting, and using drying nets that are non-toxic. 

Seaweed is an extremely nutritious plant as it absorbs all available nutrients. The ocean is the ultimate depository for the nutrients that are washed or blown off land, and seaweed soaks them up! For that very reason, it is crucial to consider where seaweed is harvested. We can look at two recent events to understand in the most basic sense why that is so important- the oil spill in the Gulf Coast, and the Fukushima nuclear disaster. Rest assured that all of the seaweed products offered through Azure are sourced from pristine waters in the Atlantic Ocean, the Norwegian Sea near Iceland, the Bay of Fundy, or were harvested in the Pacific Ocean, pre-Fukushima. Dried seaweed, properly processed and stored, has a shelf life up to two years! Unfortunately, research has shown that seaweed clear to the California coast has been contaminated with high levels of radioactive iodine and cesium xenon from the Fukushima nuclear power plant, and it will likely stick around for several decades. Azure will not sell any seaweed harvested from any contaminated regions.

Each variety of seaweed has different nutritional strengths (see this chart: ), which can also vary depending on where it was grown and how/when it was harvested. One general commonality is that seaweed is rich in iodine- how rich depends on the species. Iodine is essential for thyroid function which regulates the body’s metabolism. The thing about the thyroid, however, is that it does not distinguish between stable or radioactive iodine. That is in part why the intake of rich sources of iodine (i.e. seaweed/kelp) was/is suggested after the Fukushima accident. The thinking is to supply the thyroid with enough of the good iodine so it isn’t taking in the bad. The other reason kelp in particular is suggested, versus a simple supplement, is because the walls of kelp are made up of alginates which protect the body from many things, including various forms of radioactive substances, heavy metals, etc. They help prevent or altogether block the absorbtion, and they act as a cleansing and soothing agent to the digestive track as well.

It is also important to mention the potential correlation between seaweed consumption and decreased risk of breast cancer and tumors. Clear back to the ancient Egyptian times, and across boundaries from traditional Chinese to Ayruvedic medicine, brown seaweed has been used as a treatment for breast and other types of cancer. It has also been acknowledged that the prevalence of breast cancer in Japan where seaweed is a staple, is much less than in western countries.

One seemingly confusing factor about seaweed is its sodium content. On one hand, it is considered to be high in sodium, but it is also considered a heart healthy food. How can that be? There is a large difference between your standard table salt- or even the sea salt you get at the store, and the sodium in seaweed. The sodium chloride in table salt is accompanied by other ingredients, and it is refined. It is not a sodium solutions that works harmoniously with the body. The sodium in seaweed is naturally occuring and unrefined; it is much more bio-available and helpful to the body.

The other function of harvested seaweed has been as a fertilizer. While the Asian civilization was preparing and eating it through history, Europeans were putting it on their gardens and fields! Makes sense. All of those valuable nutrients that leached out of the soil over time, ended up in the ocean. They were absorbed by the seaweed, and the farmers figured out that supplementing their farms with seaweed kept them fertile. Today, the most common variety used for fertilizer is of the Fucaceae variety (knotted wrack, bladderwrack and rockweed). It is also a favorite for animal supplementation.

Another predominat reason for commercial seaweed production has been for the extraction of carrageenan and agar. Carrageenan is a stabilizer and widely used in food, cosmetics, pet food, and industrial applications. Agar is often used in desserts and as a natural thickener. It also proved to be an excellent medium for growing bacteria and fungi in petri dishes- utilized around the world in scientific research. Both carrageenan and agar are used as a vegetarian gelatin.

Finally, the most fun aspect of seaweed is the eating of it! Each variety has its own distinct texture and taste. They all add depth and flavoring to any dish, and this is a a rough guide for some of the common types, their characteristics and uses:
Alaria/Wakame: Mild tasting. Chewy and slightly rubbery. Good for Miso soups.
Check out these Wakame/Alaria products: CO157, CO 158, CO331, CO330, CO207, CO206
Kombu/Kelp: Can have a slightly sweet taste. Use as a soup seasoning and as cooked vegetable.
Check out these Kombu products: CO145, CO146, CO209, CO208, CO196, HS616, HS619
Hiziki: Crispy and tender with a slightly sweet flavor. Accompanies any seafood or rice dish.
Check out these Hiziki products: CO211, CO210
Nori: Sushi wraps!
Check out these Nori products: CO150, CO151, CO026, CO033, CO327, CO326, CO329, CO328, CO216, CO197, CO005, CO198
Irish Moss: High carrageenan content. Used for thickener in ice cream, puddings, etc.
Check out these Irish Moss products: CO424, CO425
Dulse: Straight out of the bag! Medium smoky taste.
Check out these Dulse products: CO124, CO125, CO017, CO016, CO187, CO186, CO192
Sea Lettuce: On salads, raw or dried.
Check out these Sea Lettuce products: CO155, CO156

Now How About Some Recipes!
Before we get to the recipes, here are a few helpful hints from Maine Coast Sea Vegetables on how to handle and prep your seaweed!
• Before using, roast plants at 350° for 5 to 8 minutes or in medium skillet until crisp, but not burned. These "chips" may be eaten as is, or crumbled over any grain dish, soup, or salad. Nori may be mixed into stir-fries and casseroles for delicate flavoring. Unroasted plants may be marinated in vinegar or lemon juice 1 to 24 hours to tenderize them. Marinated plants are great for salad and sandwiches.
• Presoaking Alaria 1 to 24 hours will reduce cooking time up to 50 percent. Removing midribs also shortens cooking time. Add a piece while cooking any grain or bean dish instead of salt. Marinate Alaria overnight in vinegar or lemon juice to obtain tender, zesty fronds for salads or stir-fries. Alaria swells to twice its volume when wet.
• Kelp is thinner and sweeter than Japanese Kombu. It provides minerals, glutamic acid (a natural flavor enhancer), and dietary fiber.
• Kelp is good for soup stocks. Leave it in to "dissolve," in approximately ½ hour, or take it out after 15 minutes. A slab of kelp in any bean-based dish will enrich digestibility and shorten cooking time. Dried kelp swells to twice its volume when wet.
• To make "chips," cut dried seaweed into bite-sized pieces and place them in a medium hot skillet with sesame or canola oil. Press each piece into hot oil with a spatula until it changes color and becomes crisp. Remove and allow to cool. Chips may also be made with dulse, alaria, or nori.

Our own Anita Pearl, Azure Standard Buyer, has an easy and excellent way to incorporate seaweed flakes into her daily diet. Here’s what she has to say:
“A little over a year ago, I started reading all I could about seaweed after hearing about its benefit for us- especially in this irradiated world. We had incorporated kelp in our diet a number of years ago, but then learned the importance of a variety of seaweeds as the nutrients are different. So, I bought one 4 ounce bag each of dulse flakes (Co124), kombu flakes (Co145), nori flakes (Co150), sea lettuce (Co155), and wakame flakes (Co157), and mixed them together in a large bowl. I filled a small container to keep in a handy spot on the counter and put the rest in a glass gallon jar. My husband and I are always finding new, delicious ways to use my “mix!” We use on salads, potatoes, eggs, in green drinks, on veggies! In fact, we use it on almost everything for which a slightly salty taste would be good. We found the recommended one/two tablespoons a day of mixed seaweed was an easy addition to our diets. I started sharing with family and now they all have the “mix” on their tables too! Sometimes we even catch our grandchildren eating it straight out of the shaker!

Here’s another recipe that might be fun for the summer! Recipe by Maine Coast Sea Vegetables:
Seaweed pickles
Fresh or dried kelp, rinsed and cut into strips 2 in x ½ in
Equal parts, Shoyu (soy sauce) and rice vinegar
Fresh garlic cloves to taste
Place kelp strips in sterilized crock or glass pickle jar
Combine remaining ingredients and pour over the kelp. Cover and refrigerate at least 24 hours.

The following websites were used in researching seaweed and developing the comparison chart:
1., The Seaweed Health Foundation, Dr. Craig Rose, 2011