From The Food Encyclopedia by Jacques Rolland and Carol Sherman
The fluid that circulates through the veins and arteries of a vertebrate animal, carrying nourishment and oxygen to cells and organs and carrying away waste products for excretion. Blood is a source of food for many cultures, some of whom drink it as is, such as the Masai tribe in Kenya, who regularly consume cow blood in the belief that it makes them strong and powerful. In other cultures, blood is cooked with other foods and is often used as a thickener. Blood pudding, also known as blood sausage, is a typical example of this type of cuisine; blood is mixed with rice, meat and spices and stuffed into a casing. Other well-known blood-based sausages are Blutwurst, boudin noir and boudin rouge. Pig and cow blood are the most common types of blood consumed, but sheep and goat blood are consumed in some areas. Poultry blood is less commonly used, but more-traditional recipes for coq au vin call for the sauce to be thickened at the end of cooking with rooster blood. Blood, specifically ox or bull blood, was traditionally used as a fining agent to clarify wines, but it is no longer used in most places. Dried bull blood was officially banned as a fining agent at the peak of the mad cow disease crisis in Europe.
