University of Córdoba Researchers Find Yeast Protein in 2,000-Year-Old Roman Wine

Researchers at the University of Córdoba said on November 6 that they have found traces of a yeast-related protein in a 2,000-year-old Roman wine from southern Spain, a discovery that they say adds new evidence linking the ancient liquid to the winemaking traditions that still define parts of Andalusia.

The finding was presented at the XVI Iberian Congress of Archaeometry and focuses on microorganisms preserved in the wine, which was discovered in 2019 inside an intact Roman tomb in Carmona, near Seville. According to the university, the newly identified protein is associated with Saccharomyces species, yeasts that play a central role in the production of some of Andalusia’s best-known white wines.

Those yeasts are especially important in wines that undergo biological aging, a process in which a layer of yeast forms on the surface of the liquid. In Spain, that layer is known as flor. It helps shape the character of white wines made in areas including Montilla-Moriles, Jerez, Sanlúcar de Barrameda and Condado de Huelva.

The research team said the presence of that biological signal in the Roman sample suggests the ancient wine may also have gone through a stage of surface yeast aging, comparable in some ways to the flor process used in traditional Andalusian wines today. The team stopped short of saying the full original process can be reconstructed, noting that 2,000 years of chemical change have heavily altered the liquid. But they said the evidence opens a new path for studying how wine was made and preserved in Roman times.

José Rafael Ruiz Arrebola, a professor at the University of Córdoba who presented the results, said the study points to the possibility that the Roman liquid experienced a biological aging phase associated with a superficial film of yeasts. He said the degree of degradation after two millennia makes it impossible to recover every original detail, but the signal offers a starting point for investigating ancient winemaking techniques with more precision.

The Carmona wine has already drawn attention in previous studies because researchers had identified it as a white wine and said it appeared to be of Andalusian origin. The new work adds a microbiological dimension to that picture. Rather than relying only on chemical composition, the team examined molecular traces left by microorganisms and proteins that remained in the sample.

To do that, the researchers used tools from molecular archaeology that can analyze both microbial DNA and preserved proteins. The university said that combining those methods with a comparison to a modern fino wine helped the team separate what may be original biological markers from changes caused by contamination or by the very long burial period. That comparison, the researchers said, is important because ancient residues often contain mixed signals created by time, environmental exposure and later handling.

The Roman wine was not found in a domestic setting and was not intended for drinking. It came from a funerary context inside a tomb in the Carmona necropolis, where it had been placed as part of a burial ritual. The liquid was preserved in a glass urn that also contained the skeletal remains of a man and a gold ring bearing an image of the god Janus, according to the university.

That context has made the find significant not only for the history of wine but also for the study of Roman daily life and funerary customs in the ancient province of Baetica. Because the tomb remained sealed until its discovery in 2019, researchers have treated it as an unusually well-preserved setting that can offer clues about ritual practices, materials and the objects placed with the dead.

The team also reported other evidence from the sample, including chemical and protein signals associated with pines. The university said those traces could point to the use of pine wood, either as a fuel source during production or as an aromatic element. Researchers did not present that as a firm conclusion, but said it is another line of evidence that may help explain how the wine was prepared or stored.

The study was carried out by specialists from the University of Córdoba’s Department of Organic Chemistry, the Institute for Chemical Research in Energy and Environment, known as Iquema, and the university’s central research support service, along with staff from the City Museum of Carmona.

For archaeologists and chemists, the main importance of the work lies in what it suggests about the survival of molecular evidence in ancient liquid remains. The university said the results show that well-preserved archaeological liquids can retain enough information to investigate where they came from, how they changed over time and part of their biological history, even after two millennia.

That could broaden the study of ancient food and drink beyond conventional residue analysis. In many archaeological settings, containers survive but their contents have long since evaporated or degraded beyond recognition. The Carmona find appears to show that under rare conditions, enough material can remain to support a much more detailed reconstruction of production methods and use.

The researchers also said the work may help build a fuller picture of Roman society in southern Spain by connecting laboratory findings with cultural evidence. In the Carmona tomb, that means looking not only at the wine itself, but also at related items such as perfumes, jewelry and other objects deposited with the dead. The sealed condition of the burial gives those materials added value because they were not disturbed over the centuries.

While many questions remain, the new results suggest that one of the most distinctive features of modern Andalusian white wine may have roots much deeper in the region’s past than previously shown in the archaeological record. The researchers said further analysis of the Carmona sample and comparison with both ancient and modern materials could help clarify how closely Roman practices resembled the methods that survive in parts of Andalusia’s wine industry.