🍱 Kaiso

Kotjitsunomata, which is the origin of "Kaisou," is a seaweed about 20 cm in height that adheres to rocks in the intertidal zone. It grows in a regular pattern, branching out in two halves. It is said that its name comes from the shape of its branches, which resemble the strings of a koto (Japanese zither). The seaweed is thickened when heated and coagulates when cooled, and was used as a soap and adhesive in the olden days. At the end of the year, merchants from Choshi sold kotojitsunomata for the New Year, and this is how it came to be used in osechi dishes. It is customary to eat refreshing "kaizo" on New Year's Day, in addition to the more flavorful osechi dishes, to improve the digestion of the stomach. In some areas, it is also used for the Obisha Festival held on the small New Year's day.