Detchi yokan is a traditional sweet popularized in Omihachiman and sold by several local confectioners. It is a simple snack made with azuki bean jam, sugar, wheat flour, agar, and water, steamed and served wrapped in a bamboo sheath. The sweet is purplish-brown in color with a soft, paste-like texture and a light, refreshing sweetness.

Compared to other, more expensive types of yokan, which usually have the texture of dense jelly, detchi yokan contains more water and less sugar. Its low price helped make it a popular snack among merchant’s apprentices or detchi, after whom the sweet is thought to be named. When these trainees returned home to Omihachiman during holidays, they would buy detchi yokan as gifts to take back to their workplaces in the big cities. An alternative theory holds that detchi comes from the word detchiru, which means kneading and mixing ingredients.

In Omihachiman, detchi yokan was traditionally made in late autumn or winter with freshly harvested azuki beans. The perishable sweet was only available from winter to early spring, but refrigeration has made it possible to enjoy detchi yokan at all times of the year.