Salt: A World History

by Mark Kurlansky

To make the sauce, the fish scraps were put in earthen jars with alternating layers of salt and weighted on the top to keep them submerged in the pickle that developed as salt drew moisture out of the fish. Classics scholars have searched for precise ancient garum recipes, but the clearest are medieval, from Geoponica, a Greek agricultural manual written about A.D. 900.

The only other place in the ancient world to use garum was Asia. The sauce appears to be, as some historians believe of the domesticated pig, an idea that occurred independently to the East and the West.

In Vietnam salt is so appreciated that poor people sometimes make a meal of nothing more than rice and a salt blend, either salt and chili powder or the more expensive salt with ground, grilled sesame seeds.

Unlike the Roman version, Asian garum has remained popular into modern times and is made virtually everywhere in Southeast Asia, including Cambodia, Myanmar, Laos, and the Philippines, where it is called bagoong.

The French, when they first encountered this sauce, apparently forgetting their own Latin heritage, were horrified that the Vietnamese ate “rotten fish.”

The fish sat in salt for three days, which produced a juice, some of which was reserved to ripen in the sun, while the remainder was pressed with the fish to produce a mush. The two were then mixed together and left for three months, sometimes much longer. Then the solid parts were strained out.

THE ROMANS, USED garum in much the same way that the Chinese used soy sauce. Rather than sprinkling salt on a dish, a few drops of garum would be added to meat, fish, vegetables, or even fruit.

According to Seneca, Apicius committed suicide because, having spent one tenth of a considerable fortune on his kitchen, he realized that he could not long continue in the style he had chosen.

Although this style of cooking was a kind of haute cuisine for the elite, costly garum was frequently described as “putrid,” which is to say rotten. “That liquid of putrefying matter,” said Pliny. Seneca, the outspoken first-century philosopher, called it “expensive liquid of bad fish.”

But Martial was probably writing about garum sociorum, which means “garum among friends,” the most expensive garum, made exclusively from mackerel in Spain.

Since the Britons both made salt and exported fish, it is likely that England too was involved in the Roman salt fish and garum trade.

Many types of garum were made—even a kosher garum, garum castimoniale, for the sizable Jewish market in Roman-occupied Israel.

The usual fish for garum—tuna, sardines, anchovies, or mackerel—all have scales and are kosher. But it seems even in the first century, a rabbinical certification brought a better price.

In 1826, a twenty-three-year-old student at the Ecole de Pharmacie, Antoine Jérôme Balard, after studying the composition of salt marshes, concluded that the blackish-purplish, foul-smelling liquid present in marsh water, the residue water from which salt crystals had formed, was a previously unidentified chemical element. Because the liquid was identical to the purple secretion of the murex, he named the new element muride. The Académie Française, wary of having major discoveries come from students, thought at the least it should not let him give the name. So they changed muride to bromine, a word meaning “stench.”

Between this stinking bromine solution from the dyeworks and the smell of fish being cured, the Roman Empire must have had a redolent coast.

when garum was made properly, the salt prevented rotting until the fermentation took hold. But it became increasingly difficult to convince people of this.

Modern divers examining a shipwreck off of southeastern Sicily found fifty Roman amphorae containing salted sardines. But in later centuries, sardines became better appreciated fresh with a sprinkling of salt.

The entire coast of the Mediterranean was studded with saltworks, some small local operations, others big commercial enterprises such as the ones in Constantinople and the Crimea. The ancient Mediterranean saltworks that had been started by the Phoenicians, like power itself, passed from Romans to Byzantines to Muslims.

VENICE, THE ONE Italian city that was not part of Roman history, was settled on islands in the lagoons in the Adriatic.

though Cassiodorus may have been overly enthusiastic about Venetian egalitarianism, the importance that he attributed to salt in Venice was not exaggerated.

About A.D. 600, Venetians started using landfill to extend the mainland closer to the islands of modern-day Venice. The Seven Seas became a landmass with a port named Chioggia. Below it, in a now much-narrowed lagoon, was Comacchio, overlooking the delta of the Po. Ravenna, formerly a port, became an inland city, and nearby Cervia became its port.

When brine reaches a sufficient density, salt precipitates out—it crystalizes, and the crystals fall to the bottom of the pond, where they can be scooped out.

In a pond with only solar heat, it may take a year or more for seawater to reach this density. But given sufficient sun and wind and a season dry enough not to have rainfall dilute the ponds, the only limit to production is the available area, the number of ponds that can operate simultaneously.

Slow evaporation results in coarse salt, and the Chinese have always considered finegrained salt to be of higher quality.

Close to Venice’s Chioggia was Comacchio, where Benedictine monks produced salt. In 932, the Venetians ended that competition by destroying the saltworks at Comacchio. But this served to strengthen the position of the third important saltworks in the area, Cervia, controlled by the archbishop of the nearby no-longer-coastal city of Ravenna.

Beginning in 1281, the government paid merchants a subsidy on salt landed in Venice from other areas. As a result, shipping salt to Venice became so profitable that the same merchants could afford to ship other goods at prices that undersold their competitors.

This meant that the Venetian public was paying extremely high prices for salt, but they did not mind expensive salt if they could dominate the spice trade and be leaders in the grain trade. When grain harvests failed in Italy, the Venetian government would use its salt income to subsidize grain imports from other parts of the Mediterranean and thereby corner the Italian grain market.

Unlike the Chinese salt monopoly, the Venetian government never owned salt but simply took a profit from regulating its trade.

Between the fourteenth and sixteenth centuries, a period when Venice was a leading port for grain and spices, between 30 and 50 percent of the tonnage of imports to Venice was in salt.

The salt administration also maintained Venice’s palatial public buildings and the complex hydraulic system that prevented the metropolis from washing away.

Producing salt for the Venetian fleet was hard work—moving mud and rocks, clearing and preparing ponds, building the dikes that separated them, carrying heavy sacks of harvested crystal. Often entire families—husband, wife, and children—labored together. They were paid by the amount of salt they harvested.

In the late thirteenth century, wishing to raise the world market price, Venice had all saltworks in Crete destroyed and banned the local production of salt. The Venetians then brought in all the salt needed for local consumption, built stores to sell the imported salt, and paid damages to the owners of saltworks.

In 1473, Venice acquired Cervia, forcing the onetime rival to agree to sell to no one but them. An exception was negotiated for Cervia to continue supplying Bologna in the nearby Po Valley. When Venice’s new archrival, Genoa, made the island of Ibiza the largest salt producer in the Mediterranean, the Venetians made Cyprus into the second largest producer.

There are a number of problems with Rusticello. He may have taken great liberties to improve on the story. Whole passages appear to have been borrowed from his previous books, which were imaginary romantic adventures. For example, the arrival of the Polos at the court of Kublai Khan bears a disturbing resemblance to the account of Tristan’s arrival in Camelot in Rusticello’s book on King Arthur.

Maccheroni, one of the oldest Italian words for pasta, appears to be from Neopolitan dialect and was used before Marco Polo’s return. The word is mentioned in a book from Genoa dated 1279. Most Sicilians are certain that the first pasta came from their island, introduced by the Muslim conquerors in the ninth century. The hard durum wheat or semolina used to make pasta was grown by the ancient Greeks, who may have made some pasta dishes, and the Romans ate something similar to lasagna.

The word lasagna may come from the ancient Greek lagana, meaning “ribbon,” or from the ancient Greek word lasanon, which probably would not make the dish Greek since the word means “chamber pot.”

Among the unexpected details in Polo’s book are many on salt and the Chinese salt administration. Polo described travelers journeying for days to get to hills where the salt was so pure it could simply be chipped away.

The valley of the Po is an anomaly of the Italian peninsula, so strikingly different that its uniqueness becomes apparent after a moment’s glance at a map of Italy.

one thick ribbon of rich, rolling green pastures stretches coast to coast along the Po. A haven for agriculture, this has always been the most affluent area in Italy, and today, known as Emilia-Romagna, it still is.

The agricultural wealth of this region depended on both a port for its goods and a source of salt for its agriculture. By competing for this business, two fiercely commercial competitors at opposite ends of the Po, Genoa on the Mediterranean and Venice on the Adriatic, became two of the greatest ports of the Middle Ages.

Historians have puzzled over Veleia because the Romans had a clear set of criteria for the sites of their cities and Veleia does not fit them. Not only is it too far from the road, it is on the cold windward side of a mountain. But it has one thing in common with almost every important city in Italy: It is near a source of salt.

In ancient times the brine wells had a huge wheel with slats inside and out for footing. Two men, chained at the neck, walked inside on the bottom, stepping from slat to slat, and two other men, also chained at the neck, did the same on the outside on top.

He who controlled the brine wells at Salsomaggiore controlled the region, and the takeover of these thirty-one brine wells marked the transfer of power from feudal lord to city government.

Parma was a good place to make ham because before the sea air reaches Parma it is caught in the mountain peaks, producing rain and drying out the wind that comes down to the plain. That dry wind is needed for aging the salted leg in a place dry enough to avoid rotting.

The sweet-smelling ham of Parma earned a reputation throughout Italy that was credited not only to the region’s dry wind but to the diet of their pigs, a diet which came from the local cheese industry. The Po Valley, where butter is preferred to olive oil, is Italy’s only important dairy region.

The difference between fresh cheese and aged cheese is salt. Italians call the curds that are eaten fresh before they begin to turn sour, ricotta, and it is made all over the peninsula in much the same way. But once salt is added, once cheese makers cure their product in brine to prevent spoilage and allow for aging, then each cheese is different.

All that is needed for cheese is milk and salt, and since domesticated animals require salt, that combination is found most everywhere.

Rennet contains rennin, an enzyme in the stomach of mammals which curdles milk to make it digestible. Usually, rennet is made from the lining of the stomach of an unweaned young animal because unweaned animals have a higher capacity to break down milk.

these stomach linings were preserved in salt so that rennet from calving season would be usable throughout the year.

the earliest surviving record of a Parma cheese that fits the modern description of Parmigiano-Reggiano is from the thirteenth century.