Casings
Traditionally, sausage casings were made of the cleaned intestines, or stomachs in the case of haggis and other traditional puddings. Today, however, natural casings are often replaced by collagen, cellulose, or even plastic casings, especially in the case of industrially manufactured sausages. Some forms of sausage, such as sliced sausage, are prepared without a casing. Additionally, luncheon meat and sausage meat are now available without casings in tin cans and jars.
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