The Anglo-Norman word boudin meant 'sausage', 'blood sausage' or 'entrails' in general. Its origin is unclear. It has been traced both to Romance and to Germanicroots, but there is not good evidence for either (cf.. The English word "pudding" probably comes from boudin.
Types
Boudin ball: A Cajun variation on boudin blanc. Instead of the filling being stuffed into pork casings, it is rolled into a ball, battered, and deep-fried.
Boudin blanc: Originally, a white sausage made of pork without the blood. Variants include:
* French/Belgian boudin blanc, with milk. Generally sautéed or grilled.
* Cajun boudin blanc, made from a pork and rice mixture in pork casings. Often includes pork liver and heart. Generally simmered or braised, although it may also be grilled.
* Boudin blanc de Rethel : a traditional French boudin, which may only contain pork meat, fresh whole eggs and milk, and cannot contain any breadcrumbs or flours/starches. It is protected under EU law with a Protected geographical indication status.
Boudin noir: A dark-hued blood sausage, containing pork, pig blood, and other ingredients. Variants of the boudin noir occur in French, Belgian, Cajun and Catalan cuisine. The Catalan version of the boudin noir is called botifarra negra. In the French Caribbean, it is known as boudin Créole. In Britain a similar sausage is called "black pudding", the word "pudding" being an anglicized pronunciation of boudin, and probably introduced after the Norman Conquest.
* Boudin rouge: In Louisiana cuisine, a sausage similar to boudin blanc, but with pork blood added to it. This originated from the French boudin noir.
Boudin vert: A green sausage made of pork meat and cabbage and kale. Popular in the Belgian province of Walloon Brabant.
Boudin valdôtain: with beetroot, spices, wine and beef or pork blood, in the French-speaking Aosta Valley of Italy;
Brown-rice boudin: Brown-rice boudin is a less common variation made from brown rice with taste similar to traditional pork boudin.
Shrimp boudin: Similar to crawfish boudin, shrimp boudin is made by adding the shrimp to rice.
"Le Boudin"
Boudin gave rise to "Le Boudin", the official march of the French Foreign Legion. "Blood sausage" is a colloquial reference to the gear that used to top the backpacks of Legionnaires. The song makes repeated reference to the fact that the Belgians do not get any "blood sausage", since the king of the Belgians at one time forbade his subjects from joining the Legion.