A sausage is a prepared food, usually made from ground meat, animal fat, salt, and spices (sometimes with other ingredients such as herbs), typically packed in a casing. Sausage making is a traditional food preservation technique.
Traditionally, casings are made of animal intestines though are now often synthetic. Some sausages are cooked during processing, and the casing may be removed at that time. Sausages may be preserved by curing, drying in cool air, or smoking.
Sausages may be classified in any number of ways, for instance by the type of meat and other ingredients they contain, or by their consistency. The most popular classification is probably by type of preparation, but even this is subject to regional differences of opinion. In the English-speaking world, the following distinction between fresh sausages, cooked sausages and dry sausages seems to be more or less accepted:
The distinct flavor of some sausages is due to fermentation by Lactobacillus during curing.
Other countries, however, use different systems of classification. Germany, for instance, which boasts more than 1200 types of sausage, distinguishes raw, cooked and pre-cooked sausages.
In Italy, the basic distinction is:
The US has a particular type called pickled sausages, commonly found in gas stations and small roadside delicatessens. These are usually smoked and/or boiled sausages of a highly processed frankfurter (hot dog) or kielbasa style plunged into a boiling brine of vinegar, salt, spices (red pepper, paprika...) and often a pink colouring, then canned in wide-mouth jars. They are available in single blister packs, e.g., Slim Jim meat snacks, or in jars atop the deli cooler. They are shelf stable, and are a frequently offered alternative to beef jerky, beef stick, and kippered (smoked) beef snacks.