The sweet potatoes are generally steamed first before peeling, slicing, and drying, with no artificial sweeteners added.

One theory holds that a rice cracker maker named Toshichi Yuasa hired a technician who modified his dried seafood processing facility to produce this agricultural product.

[7] Another theory holds that Seiji Koike and Jizan Ouchi got the backing of the governor of Ibaraki Prefecture, Masataka Mori, to start up local production with the aid of two technicians from Shizuoka.

[8] Both public and private sectors in Ibaraki Prefecture have promoted steamed dried sweet potatoes extensively.

[14] In China, a snack very similar to hoshi-imo known as "dìguā gàn" (地瓜干) is popular and in Vietnam a product known as "khoai lang sấy dẻo" is common.