Garum

Garum is an ancient fermented fish sauce dating back to Roman times. This liquid combination of fermented fish and salt was originally used by the Romans to enhance the flavor of dishes by combining garum with vinegar, oil, wine, or pepper. It was often used instead of salt, because salt extracts moisture while garum adds moisture to dishes.

In order to prepare it, tubs were filled with fish guts coming from anchovies, tuna, whitebait, mackerel, and others, and the guts were placed between layers of salt and herbs, then left to ferment in the sun for a few months. The thick liquid was garum, while the leftover paste was called allec (inferior to garum, but it was still traded or sold).