Japan Grade, Thunnus Albacares, 1.5 x 1.5cm, superfrozen at sea at -60°C. Thaw and serve This exceptional Super Frozen Japan Grade Tuna Tartare comes from the lean part of the belly. Selected when the tuna's body and fat index are optimal, the traditional Japanese ikejime method is used to perfectly preserve the integrity of the meat. It is then expertly cut at sea before being stored at -60°C ensuring unquestionable quality.