Imo-yokan (azuki-bean jelly containing sweet potato paste) (芋羊羹)
Imo-yokan is a Japanese sweet having sweet potatoes as a main ingredient that is kneaded and molded. It is used as a bait to catch a carp preferring potatoes. A product made with combination for baits is available in fishing tackle shop.
(Be careful that the product is not delicious for human beings because chrysalis powder is included in it.)
A production method
A commonly used production method is as follows. That is, a sweet potato is steamed and then is kneaded and mixed with sugar while being hot, and subsequently it is pushed into a box and then cooled to harden. Sometimes a sweet potato is boiled instead of being steamed, or a little salt or agar may be added other than sugar.
During the period from 1897 to 1902, Wasuke KOBAYASHI was a potato wholesaler in Asakusa Kotobuki-cho (present-day Kotobuki, Taito Ward, Tokyo). To make good use of the waste potatoes that were difficult to dispose, he tried to make yokan (azuki-bean jelly) with different taste from bean jelly made with agar and sugar. He approached to Sadakichi, the second generation of Japanese sweet shop 'Funasada' in Asakusa, and then 'imo-yokan' was completed by joint development. Afterwards, Wasuke learned from Sadakichi how to make imo-yokan. He trained to become a skilled artisan of Japanese sweets, and became independent by setting up a branch of the same shop to share the clientele.
Wasuke founded 'Funawa' in Asakusa 1-chome, the name of which was made by taking one character from each of 'Funasada' and 'Wasuke.'
In addition, Sadakichi and Wasuke used a character of 'Fune' because two came from Funabashi-cho (the current Funabashi City, Chiba Prefecture). Then, Sadakichi moved to Ashikaga-cho (present-day Ashikaga City, Tochigi Prefecture) with his family, and thus 'Funasada' moved to Ashikaga.
Nowadays, imo-yokan has spread all over Japan, and is familiar as a special product of sweet potato production areas such as Kawagoe City, Saitama Prefecture.