Tripe, the spongy, fleshy stomach of a cow, is used often in cooking around the world. Pork, lamb and goat tripe are also regularly consumed in other parts of the world. You will not find tripe in a regular supermarket in the U.S.; specialty ethnic markets will likely carry it, however. Tripe from the market comes already cleaned. You will only need to clean the tripe if you purchase it uncleaned -- known as "green" tripe -- straight from the slaughterhouse. Green tripe needs to be meticulously cleaned by boiling it in water and scraping off any undigested content.
Rinse tripe thoroughly under cold water until the water runs clean and you cannot see or feel any grit.
Place the tripe in boiling water in a large pot and add 1 tbsp. of salt for every liter of water in the pot. Let the tripe boil for two to three hours.
Place the boiled tripe in a pot of cold water and let it soak in the water overnight.
Scrape the insides using a knife to remove any remaining grit until the tripe is whiter and completely clean. The tripe is now ready to be cut and cooked in whatever fashion you choose. The freshly boiled tripe can be served in a stew of sautéed onions, butter and milk to make traditional English tripe and onions. An Italian version of tripe includes baking the tripe with chopped herbs, olive oil, tomatoes and cheese. In Ethiopia, tripe is stuffed with chopped steak, bread crumbs, spices and topped with spiced butter.
Tripe is often found bleached white for appearances and also to ensure that any bacteria that can be found in the stomach has been eliminated.
As an alternative cleaning method, boil the tripe first for 15 minutes, then drain the water. Pour fresh water into the pot and cook the trip for three to four hours until it is soft.
Dogs love raw green tripe; you do not have to clean it, as the leftover contents in the tripe have nutritional value for dogs.