Riblets

Pork ribs are a cut of pork popular in North American and Asian cuisines. The ribcage of a domestic pig, meat and bones together, is cut into usable pieces, prepared by smoking, grilling, or baking – usually with a sauce, often barbecue – and then served.

Several different types of ribs are available, depending on the section of rib cage from which they are cut. Variation in the thickness of the meat and bone, as well as levels of fat in each cut, can alter the flavor and texture of the prepared dish. The inner surface of the rib cage is covered by a layer of connective tissue (pleura) that is difficult to cook tender; it is usually removed before marinating or cooking.

Baby back ribs (also back ribs or loin ribs) are taken from the top of the rib cage between the spine and the spare ribs, below the loin muscle. They have meat between the bones and on top of the bones, and are shorter, curved, and sometimes meatier than spare ribs. The rack is shorter at one end, due to the natural tapering of a pig's rib cage. The shortest bones are typically only about 3 in (7.6 cm) and the longest is usually about 6 in (15 cm), depending on the size of the hog. A pig side has 15 to 16 ribs (depending on the breed), but usually two or three are left on the shoulder when it is separated from the loin. So, a rack of back ribs contains a minimum of eight ribs (some may be trimmed if damaged), but can include up to 13 ribs, depending on how it has been prepared by the butcher. A typical commercial rack has 10–13 bones. If fewer than 10 bones are present, butchers call them "cheater racks".

Rib tips are short, meaty sections of rib attached to the lower end of the spare ribs, between the ribs and the sternum. Unlike back ribs or spare ribs, the structure of the rib is provided by dense costal cartilage, not bone. Rib tips are cut away from the spare ribs when preparing St. Louis style spare ribs.

Riblets are prepared by butchers by cutting a full set of spare ribs approximately in half. This produces a set of short, flat ribs where the curved part of the rib is removed and gives them a more uniform look. Loin back ribs don't always have this removed. When not removed they have a rounded look to them and are often referred to as baby back ribs. Another product (imprecisely) called riblets is actually the transverse processes of the lumbar vertebrae. Riblets used to be thrown out by butchers, but have become popular due to their excellent flavor and lower cost.

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Wikipedia