Kombu
One of the most commonly utilized seaweeds in Oriental cuisine, kombu or konbu has long been a dietary staple in Japan, and refers to a type of brown seaweed, namely kelp of the Saccharina japonica species that is native to Japan but also extensively cultivated in China and Korea where it's known as haidai and dashima, respectively.
Apart from the great nutritional and healing values, kombu is also used for its flavor-enhancing properties: it is an invaluable natural source of glutamic acid whose powdery crystals emerge to the surface of the dried seaweed and easily dissolve in water, giving any food cooked with kombu its rich, umami flavor.
The ultimate renewable superfood, kombu is harvested at various ages, and while most of this kelp in the market is first-year kombu, what has a depth of flavor unlike any other is the second-year kombu known as ma-kombu in Japanese (lit. real or true kombu). Read more
Far more superior and more expensive, ma-kombu is the only choice in Japanese restaurants which aim for the highest quality. In Japan, people use kombu in everything, from daily meals to recipes for special occasions, and while many other types of edible seaweeds are mostly used as they are, kombu is processed and used in a wide variety of ways.
The sun-dried and either whole or powdered dashi kombu is ideal for preparing the full-bodied dashi stock, but it is also perfect for miso and other soups. Powdered kombu can even be used for brewing kombu kelp tea called kombucha.
Meat and vegetable kombu-wrapped rolls tied with dried shavings of kanpyō calabash gourd are called kombu-maki and it is one of the most popular ways to prepare kombu. Tsukudani-kombu refers to thin kombu strips or squares boiled in soy sauce and sugar.
This kombu is usually eaten with rice or wrapped in onigiri rice balls, and it tastes even better with shiitake mushrooms, sesame seeds, Japanese peppers or shiso, Japanese basil. Often a prestigious gift during the formal gift-giving seasons in Japan, shio-kombu are strips or squares of kombu that have been boiled in a sugar-flavored mixture of soy sauce and mirin, dried and then shredded.
Shio-kombu is typically eaten in ochazuke, a simple Japanese dish made by pouring green tea, dashi, or hot water over cooked rice. Tororo-kombu refers to pickled, softened kombu kelp that is used in soups such as miso, udon, and soba; topped over rice or wrapped in onigiri.
More widely used than this variety are the dried, thinly shaved tororo-kombu flakes called furikake-tororo which are often sprinkled over rice dishes, miso soup, tofu or salads. Matsumae-zuke is a type of pickled dish typically enjoyed with rice and a cup of sake.
It is made with kombu and soft dried squid called surume, both of which are cut into thin strips and mixed with boiled soy sauce, mirin, sake, sugar, and vinegar. Kizami-kombu refers to a type of dried kombu noodle-like strips that can be stir-fried with meat and vegetables or used for preparing nimono dishes.
Kombu is also often enjoyed with green tea as a crunchy snack or finger food; these leathery strips of dried kelp are often flavored with sugar or vinegar and called nakano-kombu. Varying in flavor, texture, and appearance, the countless kombu varieties some of which are detailed above are not often readily encountered outside of Japan but using any kombu found at a well-stocked Asian grocer will elevate and take your Japanese washoku cooking to the next level.