Learn about wakame (Undaria pinnatifida) seaweed’s long, rich tradition in kitchens around the globe, for its culinary uses and nutritional value – let’s take a deep dive into the history of this fascinating sea vegetable or seaweed, also known as Undaria.
About Wakame’s origins – Where does it come from?
The origin and much of wakame seaweed’s history is found in Asia, especially in Japan. Native to cold temperate coastal areas of Japan, Korea, and China, in recent decades wakame has become established in temperate regions around the world, including New Zealand, the United States, Belgium, France, Great Britain, Spain, Italy, Argentina, Australia and Mexico.
How is wakame used as a sea vegetable?
Sea vegetables like wakame have long played an important role in the eating habits of the Japanese, and excavations have shown sea plants such as wakame to have been consumed as far back as ten thousand years ago in Japan. The oldest existing anthology of Japanese poetry, the Manyoshu, which was written in the 8th century, contains early references to seaweed as a special dish served in sacred ceremonies or bestowed upon nobility as an offering. At that time, wakame was not available for daily consumption by regular Japanese people. Only after the 17th century were ordinary citizens able to obtain and eat wakame seaweed to use in their own cooking for its delicious taste and health benefits, as well as sacred properties.
How is wakame farmed?
Wakame cultivation was first studied at Dalian, northeast China, by Japanese scholar Youshiro Ohtsuki who patented cultivation techniques in 1943. Since the mid-1960s wakame seaweed has been extensively farmed there at a commercial level, but it can also be harvested from the wild. In the Republic of Korea, cultivation of wakame began in 1964, and was largely developed, promoted and industrialised throughout the 1970s, at that stage accounting for 30% of seaweed farming production in 2013.
In China, extensive production started in the mid-1980s, predominantly in two northern provinces which have since become the main wakame producers worldwide. Consumption of this macroalgae as a seafood is divided in two categories; the processed midribs are consumed inside China, while the sporophylls and blades are mainly exported to Japan and other Asian countries.
In 1983, wakame farming was deliberately introduced into the North Atlantic in the coastal areas of Brittany and initially cultivated at three sites. Wakame cultivation is also being developed in Northwest Spain.
Coming closer to home, in 2010, the New Zealand government approved commercial harvest and farming of wakame under certain conditions – simply put, that it be harvested from a man-made structure.
Wakame as an invasive species – aka a ‘weed’
Interestingly, wakame has been regarded as a noxious invasive seaweed in countries other than those where it is considered to be native. It is believed that wakame was first introduced to foreign waters through the ballast water of cargo ships from Asia, as the spores (gametophytes) contained in the water can survive long-distance journeys.
In New Zealand, wakame was in fact declared an unwanted organism in 2000 under the Biosecurity Act 1993. It was first discovered in Wellington Harbour in 1987 and it is thought it likely arrived in our water as hull fouling on shipping or fishing vessels from Asia. Wakame is now found throughout our marine environment in New Zealand, from Stewart Island to as far north as Karikari Peninsula. Even though it is an invasive seaweed, in 2012 the government allowed for the farming of wakame in Wellington, Marlborough and Banks Peninsula.
Wakame spreads in two ways: naturally, through the millions of microscopic spores released by each fertile organism, and through human activities, most commonly via the hull of shipping vessels or marine farming equipment. It is a highly successful and fertile species, which makes it a serious invader. However, its impacts are not well understood and can vary depending on the location.
Wakame: is it a friend or foe?
The downside of wakame is that it is invasive and can change the structure of ecosystems, especially in areas where native seaweeds are absent. By forming a dense canopy, it shades the sub-canopy, and can impact the growth of slower-growing native seaweed species. For instance, in New Zealand the native coralline algae which are important for paua (edible marine snail) settlement were partially displaced by wakame, resulting in decreased paua quantities.
Moreover, this invasive seaweed can affect not only the biodiversity of flora, but also the fauna communities which are based on these phytogroups. Wakame can grow on reefs which offer refuges for fish, and gradually lead to habitat loss of fishes that dwell on the reefs. Studies carried out in the Nuevo Gulf showed that the removal of wakame from invaded sites resulted in an increase in the biodiversity at those locations.
Research indicates that the wakame seaweed or sea vegetable has the potential to become a problem for marine farms because it increases labour and harvesting costs, due to fish cages, oyster racks, scallop bags and mussel ropes becoming covered. This growth can also restrict water circulation through cages.
On the flip side, Pacific Harvest is proud to offer a clean, ethically harvested wild wakame, which is densely nutritious and beneficial for health. The responsible harvesting and appropriate drying of wakame, and subsequent use of it as an amazingly beneficial kitchen pantry staple, means we rid our oceans of a ‘pest’, reduce costs of eradication, and contribute to a circular economy.
Which type of wakame to buy?
Pacific Harvest is proud to offer a clean, ethically harvested wakame, which is a dark khaki colour, and often has a lot of white powder* on the leaf. It is harvested from the ocean, where it grows on made-made structures such as muscle lines, then air dried and tested for contaminants. We thereby rid our oceans of a (highly nutritious!) ‘pest’, reduce costs of eradication, and contribute to a circular economy. Wild wakame is seasonal so not always available year around.
We sell full fronds which can be chopped into recipes or used to wrap around food parcels and baked or roasted.
Pacific Harvest also offers a farmed alternative which has been cultivated in China by a Japanese company. The quality of our seaweed is high and it is all tested for contaminants according to the Australia New Zealand food code. The farmed wakame is blanched, dried and cut into bite-size pieces, making it a very convenient addition to soups and salads. Farmed fronds will re-hydrate to a lovely green colour in a few minutes when soaked in tepid water, expanding 10 times more than that of their dry weight. The colour of farmed wakame when hydrated is far brighter than that of the wild.
Enjoy the incredible health benefits of this sustainable sea vegetable.