山芋 (Yamaimo)

Aomori has 50+ year history of nagaimo export to Asia (especially Taiwan / Hong Kong); jinenjo wild-collection cooperatives in Nagano and Hyogo set the gold standard.
Mucin-protein content 0.3–1.2% wet; diosgenin 0.05–0.2% in dried product; allantoin 50–150 mg/100g fresh.
Fresh export (Asia premium retail), freeze-dried digestive-support supplements, traditional-food convenience products.
Native Japanese yam (Dioscorea japonica) and the related cultivated nagaimo (D. opposita), distinguished by the viscous mucin-rich tuber flesh that drives both culinary and functional positioning. Aomori produces over 50% of Japan's nagaimo for export and domestic processing; jinenjo (wild yamaimo) commands premium pricing in retail and restaurants. Used in tororo, okonomiyaki batter, soba-noodle binder, and increasingly as a freeze-dried functional ingredient for digestive-support supplements.
| Japón | Food product; FFC notifications exist for diosgenin / mucin; cosmetic use under JSCI |
|---|---|
| Unión Europea | Food import; phytosanitary certificate required for fresh tuber |
| Estados Unidos | GRAS by traditional food use; MoCRA cosmetic use |
| China | Imported tuber; GACC registration; AQSIQ phytosanitary inspection |