Sargassum fusiforme

Lore & Background

Hijiki is green to brown in colour when found in the wild. Fishermen and professional divers harvest it with a sickle at low tide during the spring tide from May to March. After collection, the seaweed is boiled and dried before being sold as dried hijiki, which turns black once processed. To prepare dried hijiki for cooking, it is first soaked in water then cooked with ingredients like soy sauce and sugar to make a dish that goes by the same name. In Japan, hijiki is normally eaten with other foods such as vegetables or fish, and may be added to foods that have been steamed, boiled, marinated in soy sauce or fish sauce, cooked in oil, or added to soup, stir fries or quiches. It may be mixed with rice, but not used as a wrap, to prepare sushi. Konjac is typically prepared with hijiki mixed in to give the dish its characteristic grey color and texture. In Korea, the seaweed is called tot and eaten as namul or cooked with bap.

Reader's Guide

The word 'hijiki' first appeared in an English-language publication in 1867, in James C. Hepburn's A Japanese and English Dictionary. Starting in the 1960s, the word began to be used widely in the United States, and the product (imported in dried form from Japan) became widely available at natural food stores and Asian-American grocery stores, due to the influence of the macrobiotic movement, and in the 1970s with the growing number of Japanese restaurants. Several government food safety agencies advise consumers to avoid consumption of hijiki seaweed, as testing showed it contains significantly higher concentrations of inorganic arsenic than other types of seaweed. Agencies that advise against consumption include the Canadian Food Inspection Agency, the Food Standards Agency of the United Kingdom, and the United States Department of Agriculture. The Ministry of Health, Labour and Welfare of Japan responded with a report pointing out that while consumption of more than 4.7 g per day could exceed the tolerable daily intake, the average daily consumption for Japanese people is estimated at 0.9 g. Several reports acknowledged that occasional consumption was unlikely to cause significant health risks but advised against all consumption regardless. No known illnesses have been associated with consuming hijiki seaweed to date, but inorganic arsenic has been identified as carcinogenic to humans, and exposure has been linked with gastrointestinal effects, anemia, and liver damage. People who follow a macrobiotic diet that often includes large amounts of seaweed may be at greater risk.

Did You Know?

• Hijiki is green to brown in the wild but turns black after being boiled and dried.
• Several countries' food safety agencies advise against consuming hijiki due to inorganic arsenic content.
• The average daily consumption of hijiki in Japan is estimated at 0.9 g.