An object of the present invention is to remove or reduce iodine contained in a marine natural product extract, while maintaining the original flavor, taste, appearance, etc. of the marine natural product extract before processing. A first anion exchange membrane (5) and a second anion exchange membrane (6) are sequentially arranged from the anode (3) side. Between the anion exchange membranes (5, 6), an extract receiving compartment (9) is formed and fed with a marine natural product extract (21). An iodine recovery compartment (8) is formed on the anode side of the first anion exchange membrane (5). A replenisher receiving compartment (10) is formed on the cathode side of the second anion exchange membrane (6) and fed with a replenisher containing chlorine ions (24). During electrodialysis, the iodine ions contained in the marine natural product extract (21) pass through the first anion exchange membrane (5) and migrate into the iodine recovery compartment (8), while the chlorine ions contained in the replenisher (24) pass through the second anion exchange membrane (6) and replenish the extract receiving compartment (9).本發明係有關於一種可除去海產萃取物所含的碘、或降低海產萃取物中碘含量之方法，且能維持未經處理之海產萃取物原本所具有的風味、味道與外觀等性質。排列配置由陽極側(3)依序為第1陰離子交換膜(5)和第2陰離子交換膜(6)，兩個陰離子交換膜(5、6)之間形成萃取物收集室(9)，其可收集海產萃取物(21)。第1陰離子交換膜(5)的陽極側則形成碘回收室(8)。第2陰離子交換膜(6)的陰極側形成補充液收集室(10)，其可收集含有氯離子的補充液(24)。藉由電透析，使海產萃取物(21)中的碘離子通過第1陰離子交換膜(5)，移至碘回收室(8)；使補充液(24)中的氯離子通過第2陰離子交換膜(6)，補充至萃取物收集室(9)內。
