The ancient Spartan melas zomos (μέλας ζωμός), or black soup / black broth, was a staple soup made of boiled pigs' legs, blood, salt and vinegar.[1] It is thought that the vinegar was used as an emulsifier to keep the blood from clotting during the cooking process. The armies of Sparta and Athens mainly ate this. While it was by no means a delicacy, it kept the soldiers alive.
According to legend, a man from Sybaris, a city in southern Italy infamous for its luxury and gluttony, after tasting the Spartans' black soup said he understood why they were so willing to die. In another story, it is said that Dionysus, the despot of Sicily, for the sake of this bought a slave who had been a Spartan cook, and ordered him to prepared the broth for him, sparing no expense; but when the king tasted it he spat it out in disgust; whereupon the cook said, "Your Majesty, it is necessary to have exercised in the Spartan manner, and to have bathed in the Eurotas, in order to relish this broth."
No recipe for the Spartan black soup has survived, but blood soups are still eaten in various countries today, such as Italy and France.