Garum was an important fish sauce and condiment of the Roman Empire, one of several fish sauces manufactured and widely traded (others include muria, allex, lymphatum and liquamen). Garum is a salty, slightly fish-flavored condiment. Roman writers report that garum was used for a whole range of dishes, rather like soy sauce or Worcestershire sauce today. Garum's key ingredient was glutamic acid--a.k.a. MSG; and that makes it an "umami" sauce, one of several sauces found throughout the ancient and modern world.
Garum was traditionally made one of two ways. The dry-salting method involved placing small whole fish or the guts of larger fish into a vat. Herbs, spices and salt were added to the vat, which was then covered and left for three months to ferment.
Alternatively, garum makers began with a strong salt solution (or brine) into which they placed whole fish or fish intestines. The brine was heated over a fire until the liquid had reduced to an acceptable level.
Garum Manufacturing Sites
Roman garum manufacturing sites have been identified throughout the Roman empire. In Pompeii, garum manufacturer Aulus Umbricius Scaurus decorated an atrium of his house with a mosaic of four garum containers. Another private residence in Pompeii discovered in the 1960s had been converted for the lucrative garum manufacturing process. At this house, six large ceramic containers in the peristyle were found to have anchovy bones. Something tells me the neighbors might have complained.
Other garum production areas have been identified archaeologically in many Roman period sites including Aila (modern Aqaba) in Jordan; at Leptiminus (Lamta) and Neapolis (Nabeul) in Tunisia; Correeiros, Tróia and Setúbal in Portugal; Baelo in Spain; Cotto in Morocco; as well as many, many other locations.
Analysis of garum remnants found at the manufacturing site in Pompeii revealed free amino acids, the dominant one being mono-sodium glutamate (MSG), a result comparable to modern Italian and Asian fish sauces.
Various theories about the origins of garum suggest that the earliest form of the sauce was made by Phoenicians or Punic colonists from Asia Minor, perhaps as long ago as the 8th century BC. One possible source may have been Greeks from the Black Sea region; but from whatever source the stuff came from, it quickly became the go-to condiment to conserve fish and complement poor, cereal-based diets.
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