Wagyu A5: what the grade means and how to eat it
How Japan grades Wagyu beef, what the BMS marbling score measures, and why an A5 portion is far smaller than an ordinary ribeye.
In Japan, every beef carcass is assessed by an independent grader under a two-part system. The first part is a letter, from A to C. The second is a number, from 1 to 5.
What the letter means
The letter measures yield: how much of the carcass weight is saleable meat. A is above average, B average, C below average. It is information for the abattoir and the trade, not for the diner.
What the number means
The number is what matters at the table. It is the quality grade, awarded on four criteria assessed separately: marbling, colour and lustre of the meat, firmness and texture, and quality of the fat. The final grade is the lowest of the four.
In other words, a cut cannot score 5 if it excels on three criteria and falls short on the fourth. The system is designed to be unforgiving.
Marbling is measured separately, on a scale of 1 to 12 known as BMS. To earn a 5, a cut needs a BMS of at least 8.
Why the fat is different
Wagyu fat melts at a lower temperature than that of European beef — around 25 degrees, compared with 45. In practice, it begins to melt in the mouth.
Hence the distinctive sensation the Japanese call toroke, meaning 'melting'. It is not a figure of speech; it is chemistry.
Why the portion is small
This is the most common mistake. Anyone ordering Wagyu for the first time expects a 300-gram piece, as with a ribeye.
Wagyu A5 is so rich in fat that a portion of 100–150 grams is enough for most people. Beyond that, the richness becomes overwhelming and stops being a pleasure.
That is why it is sliced thinly, in strips, and cooked very briefly — thirty seconds a side, sometimes less. It needs no oil: it renders its own fat to cook in.
How to eat it
- Simply Coarse salt and perhaps a few drops of soy sauce. No heavy sauces to mask the flavour.
- No rich sides Plain rice or grilled vegetables. Chips clash with the fat.
- Shared A 200 g portion is better suited to two, as an opening course.
- First Eat it before a larger cut, not after. The palate is more receptive.
Why it costs so much
The cattle are raised for 28 to 36 months, compared with 18–24 for ordinary beef. Each animal has an identity certificate with a unique number, allowing it to be traced back to its farm of origin. Add refrigerated shipping from Japan and import duties.
We serve certified Japanese Wagyu A5 in two cuts: ribeye and striploin. It is ordered by the 100 grams.