The Shimanto River in Kochi Prefecture is known as Japan’s last remaining clear stream. The product is made only using 100% shirasu unagi (freshwater eel), which are carefully raised in clear groundwater from the river basin resembling an environment closer to nature with special feed created by mixing selected ingredients such as Shimanto aonori seaweed and okara (fermented soybeans) with Bacillus subtilis natto. After cutting the unagi into fillet, it is soaked in brine made with “Tosa no Shiomaru” natural salt sourced from the town of Kuroshio while raw, and then grilled. The salt water maximizes the umami flavors while grilling the fish instead of steaming brings out the best in the fatty fish. The gentle salty taste lets you discover a new way to enjoy the traditional delicacy in Japan.