A Penn researcher and colleagues have chemically identified wine residues in pottery dating back 8,000 years, indicating that the country of Georgia may be the birthplace of viticulture and winemaking.

Patrick McGovern, a biomolecular archaeologist at the Penn Museum, was the lead author of a study produced by a team of international scientists, published earlier this month in the Proceedings of the National Academy of Sciences.

The team found wine residue on pottery sherds, or fragments, from two archaeological sites in Georgia’s South Caucasus region that date to 6,000 to 5,800 B.C.E., during the early Neolithic period. That’s 600 to 1,000 years older than previously believed. The residues are from the Eurasian grape (Vitis vinifera), whose many varietals account for nearly all the wine produced today.

The new study was covered extensively in the national and international media, including The New York Times, National Public Radio, The Washington Post, National Geographic, The Guardian, and Wine Spectator. McGovern has been interviewed by 30-plus reporters since the findings were published on Nov. 13.

“The news is all over the world. It just went out like crazy,” he says. “This is a sort of sexy topic that people really want to know about.”

With this discovery, McGovern has superseded his own research. He was lead author of a 1996 study that previously established Iran as the birthplace of winemaking. Those wine residues were identified in two Penn Museum pottery jars dated to 5,400 to 5,000 B.C.E. from the Hajji Firuz Tepe site in the Zagros Mountains.

The Guinness Book of Records has already posted the new discovery as the “oldest Eurasian grape wine in the world” online.

While exhilarating to find the even-older evidence of ancient wine, McGovern admits he feels “a little sad” that the Museum’s complete reconstructed jar is now the second-oldest.

“I’ve gotten very attached to the Hajji Firuz jar,” he says. Currently on display at the Museum, the Hajji Firuz jar will be featured in the Museum’s new Middle East Galleries scheduled to open in April 2018.

McGovern is the Museum’s scientific director of the Biomolecular Archaeology Project for Cuisine, Fermented Beverages, and Health. He has made a career of finding, analyzing, and interpreting evidence of the role of alcohol in the history of humankind. At Penn since 1970, his most-recent book, “Ancient Brews: Rediscovered and Re-created,” was published in June.

It was nearly 20 years ago, in 1998, that McGovern traveled to Georgia to investigate archaeological sites and possible wine vessels in the South Caucasus, a mountainous region that straddles the Middle East and Europe. He found “tentative but tantalizing” evidence of wine then. Unfortunately, the sherds had been washed in a hydrochloric acid solution that destroyed much of the ancient organics.

With new technology available, excavations were renewed by the international team four years ago at the same sites, about 30 miles south of Georgia’s capital of Tbilisi.

The first two groups of pottery from the new excavations tested negative for tartaric acid—the principle biomarker for a Eurasian grape product, including wine. Just as the team was beginning to lose hope, six pottery sherds from a third group gave positives, McGovern says. 

“We were overwhelmed. We were thinking everything was going to be negative and all of a sudden we had these positives,” he says. “Our skepticism turned to optimism. Now we really had solid evidence that they were exploiting grapes and probably making wine.”

In addition, two sherds from the original 1998 group tested positive for tartaric acid. The detection of other organic acids (malic, citric, and succinic) found in wine provided confirmatory evidence. The team also carried out environmental and archaeobotanical research, providing further support for the history-making finding.

Extensive radiocarbon-dating by accelerator mass spectrometry of plant remains associated with the early Neolithic wine jars gave a narrow time range for their use, about 6,000-5,800 B.C.E.

“Together, these results set the whole tone for future research,” he says.

McGovern is already seeking even older evidence of viniculture in other sites in the South Caucasus, including Armenia and Azerbaijan, and farther afield in Iran, Lebanon, and eastern Turkey.

“As a medicine, social lubricant, mind-altering substance, and highly valued commodity, wine became the focus of religious cults, pharmacopoeias, cuisines, economies, and society throughout the ancient Near East,” McGovern says. “From success to success, viniculture then stretched out its tentacles and entwined itself with one culture after another: the Mediterranean, Europe, and only recently the New World.”

For now, the attention is on the eight sherds from Georgia. They were on display earlier this month at a new wine museum, La Cité du Vin, in Bordeaux, France, and McGovern says he hopes the exhibit will travel and visit Philadelphia.

“It would be nice to see the Georgian sherds next to our complete Hajji Firuz jar,” he says.