Tsukiji Market: What you need to know about Maguro (Tuna)

Bluefin Tuna When you order Akami-dane (red flesh fish) at a Sushi bar, you will invariably be given Tuna.  Unlike Shiromi-dane (white flesh fish) which include fish like Tai (Sea Bream), Hirame (Olive Flounder) and Kanpachi (Amberjack), there is essentially only one fish that qualifies as Akami-dane and that is Tuna.  But the piece of "Tuna" can come from a few sub-species which can range from

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