Kombu

To the untrained eye, one piece of dried kombu may look very much like another but, in fact, this valuable commodity is graded and categorised on a number of criteria, rather like a fine wine. Over 95% of Japans kombu comes from the seas off Hokkaido in the north of the country and, depending on the coastline where it is harvested, it is assigned one of several different names, as detailed on the opposite page. In addition to the area of harvesting, factors such as the shape of the frond and its degree of lustre are used to give each piece of kombu a rating from 1 to 6.