He deals with the dating of the Vesuvius eruption and.. garum!
Garum, made from fermenting fish in saltwater, was basically the ketchup of the ancient Romans. It boasted a much appreciated sweet and sour taste, and was used on almost on every dish, often substituting expensive salt.
Most likely it was widely available at the numerous open air trattorias, known as thermopolia, where Pompeian “fast food” was served. The sunken jars on the counter contained spiced wine, stews of meat or lentils as well as garum.
Producing garum was relatively simple. A garum maker such as Aulus Umbricius Scaurus would have first placed a layer of fish entrails on a bed of dried, aromatic herbs such as coriander, fennel, celery, mint and oregano.
Then he would have covered the fish entrails under a layer of salt about two fingers high. The layer sequence — herbs, fish and salt — was repeated until the container was filled. The concoction was then left in the sun to macerate for a week or so, and the sauce was mixed daily for about 20 days.
The process produced a smelly liquid — a local delicacy to the Romans.
“Pompeii’s last batch of garum was made with bougues, a fish that was cheap and easy to find on the market in those summer months. Still today, people living in this region make a modern version of garum, called “colatura di alici” or anchovy juice, in July when this fish abounds on the markets,” Ciarallo said.