Culinary Detectives Try to Recover the Formula for a Deliciously Fishy Roman Condiment

From Pompeii to modern laboratories, scholars are working to recreate garum, a sauce made from decaying fish that delighted ancient Rome

Illustration of fish used to make garum
Top Spanish chefs have endorsed garum as a fishy sauce with deep roots in Spanish and Roman history. Illustration by Rebecca Bradley

Garum has long been considered the dodo of gastronomic history. The fishy sauce was beloved by the ancient Greeks and Romans, but until recently, classicists believed it to be as extinct as the flightless birds of Mauritius. And garum hardly sounds like something that would tempt 21st-century taste buds. Many recipes that survive from antiquity call for allowing fish to putrefy in open vats under the Mediterranean sun for up to three months.

Complicating matters, the term could refer to both a sauce used in the cooking process—sometimes also called liquamen—and to a condiment, made with the blood and viscera of fish, that writers such as Petronius, Ausonius and Seneca knew as garum sociorum (“garum of the allies”). In either case, for most scholars, the lesson of garum (pronounced gah-room) has been that the past inhabited by Roman gourmands—known to eat sow udders, ostrich brains and roasted dormice rolled in honey—was an unimaginably foreign country. 

Ancient ruins
The ruins of a fish-salting and garum factory in what was once the Roman city of Baelo Claudia in southern Spain. Bridgeman Images

While archaeologists have excavated concrete vats used for making garum from Tunisia to France, intact organic remains have proven harder to come by. A breakthrough occurred in 2009, when Italian researchers discovered six sealed dolia (large clay storage vessels) in a building that modern scholars have dubbed the Garum Shop at Pompeii. The eruption of Mount Vesuvius in A.D. 79 buried the building under several feet of ash, perfectly preserving a small factory just as it was salting down a late-summer catch of locally fished picarel to make liquamen.

Food technicians from the universities of Cádiz and Seville have analyzed the charred, powdered remains from Pompeii. Using that information, and guided by a liquamen recipe thought to have been written in the third century A.D.—it calls for heavily salted small fish to be fermented with dill, coriander, fennel and other dried herbs in a closed vessel for one week—the researchers produced what they claim is the first scientific recreation of the 2,000-year-old fish sauce. 

“Flor de Garum”  is being sold in amphora-shaped glass bottles in Spain. Chefs say it supercharges dishes with a potent hit of umami, the pleasantly savory “fifth taste” conveyed by foods rich in glutamates.

Flasks of Flor de Garum
Flasks of Flor de Garum are shaped like ancient amphorae to convey the seasoning’s classical roots. Matiz Espana

At his laboratory at the University of Cádiz, Víctor Palacios, a chemical engineer, recently showed me a petri dish filled with gritty, grayish-brown powder—a sample of the charred paste of fish bones recovered from the Garum Shop at Pompeii. Using a gas chromatograph and a scanning electron microscope, researchers at the University of Las Palmas de Gran Canaria identified the fish as anchovies. Specialists at the University of Alcalá de Henares performed pollen analysis, which indicated the presence of mint, sage, thyme, oregano and other herbs. Most ancient recipes call for whole small fatty fish to be layered between herbs and salt in concrete vats. Palacios’ team used large glass fermenting vessels.

“We bought the anchovies fresh from fishing boats at a local pier,” Palacios says. “We used three parts fish for one part salt.” 

When small fish start to decay, the bacterial flora in their guts burst through cell walls, initiating the process of autolysis. The fish essentially digest themselves, liquefying the proteins in muscle tissue. The presence of salt slows this fermentation process, promoting lactic acid bacteria that defeat pathogens and such foul-smelling toxins as cadaverine and putrescine. (Too much salt stops autolysis altogether; too little invites botulism.) Palacios’ team found that the result, after 25 days, was a paste of dissolved fish bones and flesh topped by a salty, amber-hued liquid, which smelled like a “mixture of dried fish, seaweed and spices.” The sauce proved to be a protein bomb, especially rich in glutamic acid, the same amino acid that gives Parmesan cheese, tamari sauce and cooked mushrooms their savory, umami intensity.

“The first time we made it,” Palacios says, “it came out perfectly.” 

Top chefs in Madrid and Barcelona soon joined Cádiz’s Michelin-starred Mauro Barreiro in endorsing Flor de Garum as a sauce with deep roots in Spanish and Roman history. “Our garum is very salty, very concentrated,” Palacios tells me. “But the aromatic herbs make it distinct from other fish sauces. When Japanese clients try our garum, they call it the ‘umami of the Mediterranean.’”

I tasted the results at El Faro, a restaurant in Cádiz celebrated for its respectful takes on classic Andalusian seafood dishes. Mario Jiménez Córdoba, El Faro’s chef, prepared an appetizer of black-truffle ice cream mixed with lashings of liquamen, raw sea bass marinated in oxygarum (an amalgam of wine vinegar and fish sauce) and a chocolate ganache seasoned with Flor de Garum. Rather than overpowering the sweet and savory flavors, the sauce intensified and united them, as if each dish had been subjected to the culinary equivalent of italicization. 

“When people think of garum,” Jiménez says, “they imagine something that smells disgusting. But we have to think of garum like we would salt, or soy sauce. You use only a few drops, and the flavor is incredible.” 

It makes sense that Cádiz, founded as Gadir by the seafaring Phoenicians at the beginning of the first millennium B.C., should have inspired garum’s modern renaissance. The marshes that bracket the old town allowed the development of salterns, which have been celebrated since Roman times for producing fine, hand-harvested salt flakes. By the beginning of the imperial period, the region around Cádiz was famous for its cetariae, fish-salting factories that dispatched high-quality garum sociorum (the condiment version) and ordinary liquamen in terra-cotta amphorae to Gaul, Greece, Egypt and Rome. Marine archaeologists continue to salvage ships laden with cargos of garum amphorae sunk by storms off Spain’s Mediterranean coast; one of the largest, a 100-foot-long merchant ship discovered off Alicante in 2001, carried 2,500 amphorae, each of which could have held up to ten gallons of fish sauce. Sixty miles southeast of Cádiz, the ruins of the Roman outpost of Baelo Claudia include a shorefront complex of concrete vats, each capacious enough to salt thousand-pound bluefin tuna, a now-endangered species whose migration route still takes them through the nearby Straits of Gibraltar.

ruins of ancient Roman factory
In what is now Barcelona, this ancient Roman factory turned out garum as well as salted fish in the third century A.D. Getty Images

Some food historians say it’s impossible to recreate definitive modern versions of these Roman ancient fish sauces. Not only did the Romans consume at least two distinct kinds of garum, but factories in North Africa, Brittany, Spain and other parts of the empire would have used different species of fish—and followed different recipes. Before leaving Spain, I met Darío Bernal-Casasola, a classical archaeologist at the University of Cádiz, who oversaw the excavation of Pompeii’s Garum Shop.

“This is the first time in modern history,” Bernal-Casasola says, “that a scientific reconstruction of garum has been attempted.” But he points out that Flor de Garum isn’t exactly the same as the ancient sauce produced in Cádiz. Rather, “it’s the garum they were making in Pompeii on August 24, A.D. 79, the day Vesuvius erupted.” Or rather, he adds, it’s the closest we can get to it—because we can’t be sure which herbs they were using, the proportions or exactly which recipe they were following.

Sally Grainger, an independent researcher and author of The Story of Garum, published last December, also praises Palacios’ effort. But she believes that what the Cádiz team actually produced was a form of liquamen, and because they combined techniques from different recipes, she doubts whether their claims of authenticity are completely justified.

The aforementioned  recipe attributed to the third century (a date that Grainger disputes) “was designed for making small batches in home kitchens,” and would have resulted in something similar but not identical to liquamen; the liquamen familiar to most Romans would have been fermented for months in open vats, in factories throughout the empire. A question remains: Can garum sociorum, the condiment favored by elite Roman diners, be recovered? Palacios and his team tried to recreate the sauce by salting down mackerel. They even built vats on the beach at Baelo Claudia to replicate conditions from two millennia ago. But after six months, the fermentation remained incomplete. Grainger’s own attempts at making the condiment have also been inconclusive. After fishing in the English Channel, she salted the blood and viscera of mackerel in aquariums in a greenhouse next to her East Hampshire cottage in southern England. The process was labor-intensive—each fish yielded only a tablespoon or two of blood—and Grainger describes the resulting sauce as “weird...not to everyone’s taste.”

Still, Grainger offers accessible options for those eager to get an idea of what ancient Roman fish sauces tasted like. She singles out Red Boat, a brand of Vietnamese nuoc mam nhi made with black anchovies and salt, and no sweeteners, as the closest thing on the market to liquamen; it is widely available in various grocery stores. Grainger also believes she has located a modern analogue to garum sociorum. For at least 300 years, a similar sauce, ishiri, has been made in Japan’s Ishikawa Prefecture from the fermented blood and viscera of squid. Opaque and rich in proteins, ishiri has the same metallic taste she detected in her experiments with mackerel. Like garum sociorum, it is meant to be used as a condiment, rather than in the cooking process.

Until experimental archaeologists definitively resolve the mystery of garum sociorum, I figure ishiri might be the next best thing. I’m expecting the bottle I’ve ordered from Japan to arrive any day. 


Please Pass the Flavor

Far-flung forerunners of the world’s favorite condiments
By Ted Scheinman

An illustration of a mustard plant


Using seeds from the Brassica juncea plant as seasoning dates at least to 3,000 B.C. in Sumeria and India; the Sumerians were likely the first to grind them into a paste. King Tut was buried with a passel of the seeds, to spice up the afterlife. The Romans mixed the ground seeds with wine, creating a tart sauce we might recognize today. The sauce was later called mustum ardens—Latin for “burning wine”—and shortened to “mustard.”

An illustration of a soy bean plant

Soy Sauce

One of soy sauce’s main forerunners was a flavorful Chinese paste known as jiang, which emerged before 256 B.C. and was made with fermented meat, fish or grain. Sometime around A.D. 960-1279, jiangyou appeared—a more watery condiment, made by boiling and fermenting soybeans in brine.  By the 17th century, Japanese soy sauce—shoyu, predecessor of the English term—had evolved into one quite similar to the liquid found in kitchens today.


Though several ancient cultures ground sesame seeds into a condiment, it was in the 13th century that cooks in Persia first pulverized the seeds with oil into a spread called ardeh, later known as tahina, from the Arabic verb “to crush.” The high price of the seeds made tahini a luxury product for several centuries; like salt among Phoenicians or cacao beans among certain Mesoamerican cultures, sesame seeds were sometimes used as curren.

sesame and tomato
The sesame plant, left, and tomato plant, right. Alamy


In southern China c. 300 B.C., chefs introduced a sauce called ge-thcup or koe-cheup, made from fermented fish and soybeans. In the 16th and 17th centuries, Dutch and English merchants liked koe-cheup so much they brought it home with them. In England, early ketchup (or catsup) used fermented oysters or anchovies (or fruits and vegetables). Tomatoes, which Europeans long deemed poisonous, didn’t enter recipes until 1830s America.

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