In the old days, Shinagawa-shuku was a seaweed production area. As a vestige of that, each family has its own seasoning, but the tradition of simmering fresh seaweed remains. More than half of the fresh seaweed that enters Tsukiji Market is said to be consumed in the Johnan area.

生海苔煮
江戸自慢三十六の図 品川海苔