Writer: Yumiko Ishimaru
90% of the domestic production of kombu in Japan is from Hokkaido. However, species of kombu vary by region even within Hokkaido; the name of region becomes the brand-names.
The following four kinds are generally good to use for dashi:
Ma-kombu is from the southern part of Hokkaido. It is known as the king of kelp because of its ability to produce crystal clear, rich and refined dashi stock. It is very thick and wide. It is used for high-class tsukudani (small seafood that has been simmered in soy sauce and mirin), tororo-kombu (pickled, softened kombu kelp that is layered, pressed, and thinly shaved) and oboro-kombu (dried shredded kombu kelp).
Rishiri-kombu is sweeter, saltier, and harder than ma-kombu. It is popular in kaiseki dishes in Kyoto. Its dashi is very rich, savory, and clear. It is often used for dashi stock in nabe (Japanese hot pot) and yu-dofu (tofu cooked in dashi stock).
Rausu-kombu is from the northern part of Hokkaido. The official name is “Rishiri Enagaoni Kombu”. Its stock is characteristically kombu-colored, fragrant, soft, and rich. It is called the king of dashi stock. It is mainly used to make stock for nabe and nimono (simmered vegetables, meats, fish, seaweed and tofu with dashi, sake, soy sauce and a small amount of sweetener).
Hidaka-kombu is from the Hidaka area of Hokkaido (Pacific side). It is soft and cooks quickly. It is used in many prepared dishes such as nimono and kombu-maki as well as dashi stock.
Kombu products: from left, Ma-kombu, Rishiri-kombu, Rausu-kombu and Hidaka-kombu.