In 1641 Japan closed the border for over 200 years to any foreign country except Holland. The Japanese did not allow the Dutch to come on the mainland, but on the island Deshima in Japanese waters the Dutch and Japanese merchants did their business. Our Yamaki miso’s and shoyu’s were already made with the same recipe as in that time.

Deshima (literally "protruding island"; Dutch: Desjima or Dejima, often latinised as Decima), was a fan-shaped artificial island constructed in 1634 on orders of shogun Iemitsu in the bay of Nagasaki, that was a Dutch trading post during Japan's self-imposed isolation (sakoku) of the Edo period, from 1641 until 1853.

Deshima was a small island, 120 by 75 meters, linked to the mainland by a small bridge, guarded on both sides and with a gate on the Dutch side. It contained houses for about twenty Dutchmen, warehouses, and accommodation for Japanese government officials. The Dutch were watched by a number of Japanese officials. Deshima was under direct central supervision of Edo by a governor, called a bugyō, who was responsible for all contacts between the VOC (Vereenigde Oostindische Compagnie, translated to english as United East Indian Company) and all contacts with anyone in the Japanese archipelago. Every Dutch ship that arrived in Deshima was inspected by the bugyō, and sails were seized until that ship was set to leave.