Are All Meat Casings Edible?

Elizabeth Boyle, Ph.D. and Rodolfo Estrada
Department of Animal Sciences and Industry
Kansas State University
January 1995

Fresh pork sausage may be marketed as bulk sausage, in plastic tubes or as links. The only difference between these three products is the type of packaging material, or casing, that is used to surround the sausage. Bulk sausage typically would be marketed in a styrofoam tray covered with an oxygen permeable film. Pork sausage distributed in plastic tubes is often sliced by the consumer with the packaging still covering the sausage so uniform patties are obtained. The plastic casing is then discarded before cooking. Pork sausage links are usually cooked and consumed without removing the casing. It is important to recognize that not all meat casings are edible.

There are many types of casings used to surround processed meat products. Before the development of manufactured casings, only natural casing were used by sausage makers. Natural casings are derived from the gastro-intestinal tracts of swine, cattle and sheep. Hog casings are obtained from the stomach, and small, large and terminal portions of the intestines. They are commonly used to stuff Italian sausage, smoked sausage, bratwurst and pork sausage. While less tender than sheep casings, hog casings are usually consumed with the sausage.

The esophagus, small and large intestine, bung and bladder from cattle are used as beef casings. Ring bologna, blood sausage, polish sausage and dry sausages are examples of products that may be stuffed into beef casings. Certain Italian specialties such as mortadellas are stuffed in beef bladders. Beef casings, however, are the toughest of the natural casings and are usually peeled off the product after cooking.

Obtained from the intestines of sheep, sheep casings are very tender and may be used for bockwurst, natural casing frankfurters and pork sausage. Sheep casings are digestible and are consumed with the product.

Casings made from cellulose, inedible collagen, edible collagen and plastic are four classes of manufactured casings that are used on processed meat products. Cellulose casings are strong casings made from cotton fibers or wood pulp that are used on sausage products of all sizes and shapes. This is a paper-type casing that should be removed before the meat product is consumed.

Collagen extracted from skins and hides is used to make edible and inedible collagen casings. As with natural casings, edible collagen casings are used for fresh pork sausage links and frankfurters. Plastic casings, also called chub packages, are used to market ground beef and fresh pork sausage. All plastic casings must be removed before meat products are consumed. The use of casings provides you with a large selection of processed meat products to suit your taste.