Relatives of the grapevines that produce nearly all the wine made in the world today were first cultivated in Eurasia, in the area of the modern-day Republic of Georgia, about 8000 years ago, according to researchers working on the Gadachrili Gora Regional Archaeological Project Expedition, or GRAPE, a venture between Canada’s University of Toronto and the Georgian National Museum.
The team of scientists has uncovered evidence of the earliest winemaking anywhere in the world, dating the origin of the practice to the Neolithic period around 6000 BCE, pushing it back between 600 to 1000 years from the previously accepted date. Their findings are reported in a research study this week in the Proceedings of the National Academy of Sciences.
"We believe this is the oldest example of the domestication of a wild-growing Eurasian grapevine solely for the production of wine," says Stephen Batiuk, a University of Toronto senior research associate and co-author of the study.
"The infinite range of flavors and aromas of today's 8000 to 10,000 grape varieties are the end result of the domesticated Eurasian grapevine being transplanted and crossed with wild grapevines elsewhere over and over again," Batiuk says.
"The Eurasian grapevine that now accounts for 99.9% of wine made in the world today, has its roots in Caucasia."
The earliest previously known chemical evidence of wine dated to between 5400 and 5000 BCE, and was from an area in the Zagros Mountains of Iran. Researchers now say the practice began hundreds of years earlier, in the South Caucasus region on the border of Eastern Europe and Western Asia.
The researchers say the combined archaeological, chemical, botanical, climatic and radiocarbon data provided by the analysis demonstrate that the Eurasian grapevine Vitis vinifera was abundant around the sites. It grew under ideal environmental conditions in early Neolithic times, similar to premium wine-producing regions in Italy and southern France today.
"Our research suggests that one of the primary adaptations of the Neolithic way of life as it spread to Caucasia was viticulture," Batiuk says. "The domestication of the grape apparently led eventually to the emergence of a wine culture in the region."
Batiuk describes an ancient society in which the drinking and offering of wine penetrates and permeates nearly every aspect of life from medical practice to special celebrations, from birth to death, to everyday meals at which toasting was common.
"As a medicine, social lubricant, mind-altering substance, and highly valued commodity, wine became the focus of religious cults, pharmacopeias, cuisines, economics, and society throughout the ancient Near East," he says.
He cites ancient viniculture as a prime example of human ingenuity in developing horticulture, and creative uses for its byproducts.
The GRAPE excavations have focused on two Early Ceramic Neolithic sites (dating to 6000 and 4500 BCE) called Gadachrili Gora and Shulaveris Gora, about 50 kilometres south of the Georgian capital of Tbilisi. It’s an area that has been the subject of several archaeological studies over many years, as researchers investigate settlement organisation, architectural techniques, and evidence regarding “the processes of neolithisation”.
Pottery fragments of ceramic jars containing residue preserved inside for several millennia were recovered from the sites. Scientists at the University of Pennsylvania, US, collected and analysed the materials using the newest methods of chemical extraction and confirmed the presence of tartaric acid, a key indicator grapes and wine, along with three associated organic acids — malic, succinic and citric – in the residue recovered from eight large jars.
The Neolithic period is characterised by activities that include the beginning of farming, the domestication of animals, the development of crafts such as pottery and weaving, and the making of polished stone tools.
GRAPE is part of an international, interdisciplinary project involving researchers from the United States, Denmark, France, Italy and Israel.
"In essence what we are examining is how the Neolithic package of agricultural activity, tool-making and crafts that developed further south in modern Iraq, Syria and Turkey adapted as it was introduced into different regions with different climate and plant life," Batiuk says.
"The horticultural potential of the south Caucasus was bound to lead to the domestication of many new and different species, and innovative 'secondary' products were bound to emerge."