Marbling Score (Marb)
Marbling, or intramuscular fat, is the estimate of the amount of fat present in the loin / ribeye (longissimus dorsi) muscle. Graders evaluate the amount of intramuscular fat at the cut surface of the ribeye on the 12th rib surface. There are 9 marbling scores and each of these is divided into 100 subunits. They are assigned as subscripts to the scores ranging from 00 to 99, representing the least and greatest amount of marbling within the score.
Wyo Beef's Commitment To Superior Beef is highlighted by the fact that we ultrasound each carcass for marbling and tenderness. Any carcass that does not meet high choice or prime at the time of ultrasound and scores in the top range of the tenderness scale will not be sold as Custom Bulk Beef!
The purpose of quality grades is to segregate beef carcasses into palatability groups based on the expected eating quality. Quality grades are based on degree of marbling and carcass maturity. Carcass maturity groups range from A to E and are an estimate of the animal’s age from which the carcass was derived. Maturity group A cattle are estimated to be between 9 – 30 months old, while group E cattle are greater than 96 months. The quality grades are (from most palatable to least) Prime, Choice, Select, Standard, Commercial, Utility, Cutter, and Canner. The relationship between marbling, maturity and quality grades are shown below.
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