Kombu
Kombu is edible kelp, usually from the genus Saccharina, prized in Japanese cooking for its savory glutamates and use in dashi.
Dashi: A Japanese stock commonly made by steeping kombu and dried fish or mushrooms in water. Kombu supplies much of the glutamate that gives classic dashi its savory depth.
Glutamic acid: An amino acid whose ionized form, glutamate, contributes a savory taste called umami. Kombu’s glutamate is the main source of its characteristic savory taste.
Hokkaido: The northernmost of Japan’s four main islands and a major region for kelp harvesting. Hokkaido is the source of many prized kombu varieties.
Wakame: An edible brown seaweed, usually Undaria pinnatifida, commonly served in soups and salads. Unlike kombu, wakame is usually eaten as a tender vegetable rather than used chiefly for stock.
Kombu tea: A savory drink made by steeping kombu or dissolving powdered kombu in hot water. It uses kombu’s umami as a drink rather than as a stock ingredient.
Umami: One of the basic tastes, associated with glutamate and certain nucleotides. Kombu is a celebrated natural source of this taste.
Rishiri Island: An island north of Hokkaido known for producing Rishiri kombu. Its clear, mild-tasting kelp is valued for refined dashi.
Nori: Edible red algae processed into thin sheets for foods such as sushi. Nori is a different kind of seaweed, valued for sheets rather than kombu’s broth-making properties.
Tsukudani: A Japanese preserve made by simmering ingredients in soy sauce and sugar. Kombu is often simmered this way into a concentrated, chewy side dish.
Inosinate: A nucleotide that enhances umami, especially in combination with glutamate. Its synergy with kombu’s glutamate explains why kombu and dried fish make especially savory dashi.