The usda defines an extra lean cut of beef as a 3 5 ounce serving about 100 grams that contains fewer than 5 grams total fat 2 grams of which are saturated fat and 95 milligrams of cholesterol.
Which cut of beef has the most marbling.
When beef graders yes there are people who grade beef for a living are grading beef they specifically look at amount of marbling in the ribeye muscle between the 12 th and 13 th ribs.
Indeed to ensure an apples to apples comparison or steak to steak if you prefer inspectors look at the loin muscle specifically between the 12th and 13th ribs which is where the short loin primal cut meets its next.
Beef carcass quality grading is based on 1 degree of marbling and 2 degree of maturity.
Graders evaluate the amount and distribution of marbling in the ribeye muscle at the cut surface after the carcass has been ribbed between the 12th and 13th ribs.
The beef rib and short loin are among the most marbled sections while the beef round and sirloin tend to have the least.