USDA Lamb and Lamb Varieties and Their Significance
There is something exclusively meat in lamb. I do not mean that he has a lot of meat on his bones – although he can. I mean, this is how it should feel when eating meat. It is often on the bone and has a strong, deep flavor that is the exact opposite of sterile little chicken tenderloin.
Like beef , not all lamb is the same, but the varieties of lamb you see in the grocery store or market are less diverse. According to meatscience.org , “[m] ore over 90 percent of US lamb will meet USDA Prime or Choice requirements.” However, there are three more grades – Good, Utility, and Culling. As with beef, a lamb’s score is highly dependent on the amount of fat present, although age and muscle “thickness” also affect the score.
basic
Young lambs (six to eight weeks old) with “thick muscles” and streaks of fat on the sides ranging from “small” to “abundant” are considered first class. But with age, sheep’s need for fat increases. An older lamb needs modest to abundant veins to be considered first class; 1-year-old mutton should have at least moderate fat streaks. When a sheep develops into “mutton territory” (over 20 months old), meat can no longer be rated Prime, no matter how greasy it is. (See this USDA graph for a visual representation.) All Prime lamb bran will be tender either due to youthfulness or the amount of fat present, but I still prefer to try the meat in the store and go for chops or steaks with the greatest marbling.
Choice
Young lamb with “slight” or “slight” streaks of fat on the sides is considered the choice, but the amount of fat needed to maintain this rating increases with the age of the lamb. If you buy lamb from the grocery store or butcher shop, it will most likely have a Choice rating, which means it will have “moderate” to “heavy” fat streaks on the sides. Since you have no way of knowing exactly how old the sheep was, it is a good idea to look for fat and select the cuts with the largest stripes or marbling.
Good
Lamb rated “Good” has “slightly thin muscles” and can range from “virtually no” fat streaks on the flanks to “moderate” amounts, depending on the age of the animal. (Again, this graph is really helpful.) You will most likely not come across whole cuts of lamb marked “Good” as this meat is usually minced or processed to make other foods.
Utility and rejection
These two are the bottom of the barrel, so to speak. Usefulness may be “striped” (assuming the lamb is young), and lamb with this rating may be “virtually none” or even “modest” fat streaks on the sides. The term “culling” is used to refer to meat that does not meet even these meager criteria. All varietal meats and discarded meats are processed into other products, although I cannot tell you which variety is included in which products. (I bet some of it ends up in dog food.)