Almost like our mayonnaise, ketchup or tomato sauce accompanying many of our meals and dishes, the Romans had their own typical sauce: garum. Because of its high price and scarcity, it might be better to compare it with the occasional spices or condiments more expensive and bizarre of our time, but hey, it serves as an introduction to this sauce.
The garum, Roman delight, was produced as follows: they used fish guts or, occasionally, the whole fish, and left it marinate in salt for a few days. What remained after this first step, was “distilled” by passing it through successive strainers making it increasingly finer, and of course, more expensive in each distillate.
As you see, the truth is that Roman delight does not seem very appealing at first glance. Also the smell should not be very attractive since the great chef Apicius recommended avoiding the smell of garum with laurel, honey and wine.
Perhaps the closest food to garum among the ones known nowadays could be anchovies paste, slightly denser than oil. Now… does anybody want to join me to have lunch at an Italian restaurant? 
The garum produced throughout the southern Iberia and the coastal strip between the current Lisbon and Cartagena had a special fame and was very appreciated the one manufactured in Baelo Claudia, in the Strait of Gibraltar, because it was made with tuna.
The disappearance of this sauce in the kitchens, in the Mediterranean trade, resulted from the breakup of the Roman Empire after the invasion of the barbarian peoples of northern Europe. The disappearance of virtually all communications infrastructures and the impoverishment of the population made garum a not very popular food. It only kept being produced in specific locations until almost the middle ages, especially in the Byzantine Empire, but not only there.
This product was targeted to large cities and therefore was an expensive luxury, which made it a great deal for those who manufactured the product. The location of the industries were generally in the suburbs of the coastal cities where they were produced or, as in the case of Baelo Claudia, where the economic base of the city’s economy was based.
Place to make garum. Photo by Poblado de Doña Blanca.
