Wagyu — The Marbling Science and Grading System (和牛)

Japan — the four Wagyu breeds were developed through selective breeding of native Japanese cattle with imported European breeds from the late 19th century. Kobe beef (神戸牛) is Tajima-gyu cattle raised in Hyogo Prefecture under strict standards — one of Japan's most famous geographical food indications.

Wagyu (和牛, Japanese cow) refers to four specific Japanese cattle breeds — Kuroge Wagyu (Japanese Black, the dominant breed), Akage Wagyu, Nihon Tankaku Wagyu, and Mukaku Wagyu — characterised by their extraordinary intramuscular fat (shimofuri, 霜降り, frost pattern). The fat marbling produces beef of extraordinary tenderness and a distinctive buttery, umami-rich flavour from the high proportion of oleic acid in the fat. Wagyu is graded by Japan's Beef Marbling Standard (BMS 1–12), with BMS 6–12 representing premium quality. The A5 designation (A = yield grade, 5 = highest quality score) is the commercial summit.

Wagyu's flavour is defined by its fat: the high oleic acid creates a buttery, clean, rich sensation rather than the heavier saturated-fat character of conventional beef. The intramuscular fat delivers umami alongside fat richness — the beef tastes simultaneously fatty and deeply savoury. BMS 10–12 Wagyu eaten as shabu-shabu slices has a sweetness from the rapidly rendered oleic fat that is unlike any other meat experience. The lean meat, when present, is deeply iron-mineral and savoury.