Gyukakuso' (a plant of a buckwheat family, scientific name: Polygonum Thunbergii) that had been grown along the area of the Asakawa river, which was a tributary of the Tamagawa river, near Hijikata's house, was its raw material.
土方家のすぐ近くにある、多摩川の支流の淺川（浅川(東京都)）に生えている牛革草（ぎゅうかくそう、ミゾソバのこと）を原材料にしている。