Striploin

A Japanese menu writing サーロイン is describing what American fabrication calls the strip loin: NAMP 180, the New York strip. It is a loin cut, taken from the back behind the ribs. It is not the American sirloin.

The American sirloin is a different region, further back toward the hip. Its closest Japanese counterpart is らんいち, ran-ichi, one of the 13 official Japanese cuts, which subdivides into ランプ ranpu as the top sirloin and イチボ ichibo as the cap. Even that correspondence is approximate, because the U.S. sirloin also takes in bottom-sirloin cuts such as tri-tip that ran-ichi does not.

The practical consequence is worth stating plainly. If you order sirloin expecting the Japanese meaning and receive the American one, you have bought meat from a different part of the animal with a different texture and a different price. The fix is not to learn a conversion table, because there is not a clean one. It is to ask which muscle, or to read the seller's own cut description.

Striploin and ribeye are neighbours on the same muscle, the longissimus, and they are cut on either side of the point where the rib primal ends. Striploin is usually the firmer of the two, with a tighter grain and marbling distributed more evenly through the muscle rather than pooled around the seams of a rib cap.

That evenness is why some people prefer it in Wagyu specifically. At high marbling scores a ribeye can be very rich in the cap, and a strip gives a more consistent bite across the slice. Neither is better; they fail differently, and the choice is about how much richness you want in one mouthful.

Fabrication specifications vary between sellers, so the trim, the fat cap and whether the strip is cut bone-in all change what arrives. Compare the seller's description rather than relying on the name, and treat NAMP 180 as the useful precise reference when a seller quotes it.

Then ask the two questions any Wagyu claim should answer: where it came from, and what it graded. Origin is a prefecture, a named producer or a country. Grade is a Japanese letter and number, a USDA grade, or an Australian marble score, and none of the three converts exactly into another.