Researchers have found what they believe is the world earliest evidence of mashed grapes, dating back to 6500 years ago in Greece.
The 2,460 charred grape seeds and 300 empty grape skins were used to make wine, and might be the remains of the second oldest known grape wine in the world, the first being the residue-covered Iranian wine jug dating back to the sixth millennium BC.
Lead author Tania Valamoti, a lecturer in the Department of Archaeology at Greece's Aristotle University of Thessaloniki, and her team excavated four homes at a Neolithic site called Dikili Tash.
After discovering the grape remains in one residence, they conducted charring experiments on fresh grapes, raisins and wine pressings to see what would best match the ancient seeds and skins.
They found the archaeological remains "morphologically resembled wine pressings and could not have originated from charred grapes or raisins".
Analysis of the grape remains further revealed they either were harvested from wild plants or originated from a very early cultivar.
"For the Neolithic or the Bronze Age, we have no evidence for markets and a market economy. Production was on a household or communal basis," Discovery quoted Valamoti as saying.
Valamoti and her team also found two-handled clay cups and jars, which they said suggested a use for decanting and consuming liquids.
Charred figs were also found near the grape remnants.
Since the juice from wild grapes often has a bitter taste, figs could have used as a flavour. The world's oldest wine, a 9,000-year old rice wine from China, also contained honey and fruits, she said.
"Figs could have been added to the grape juice prior to fermentation and the sugars contained in them would have entered the juice. Or, they could have been added to the fermented product after completion of the fermentation process. Honey could be dealt with in the same way," Valamoti added.
Valamoti and her colleagues are now looking forward to conduct studies on the Dikili Tash pottery to determine whether tartaric acid, a component of grapes and wine, was present in the cups.
The study is published in the journal Antiquities.