Would be very old indeed if a recent article in Scientific American is to be believed. It appears that proof has been found that Chinese villagers brewed alcoholic beverages more than 9000 years ago. A technique known as mass spectrometry was used by researchers at the Pennsylvanian Museum of Archaelogy to detect tartaric acid (a bi-product of grape fermentation) on shards of pottery that dated from around 7000 BC. The tests revealed that:
"13 of the 16 remnants came from containers that had held the same liquid, a "mixed fermented beverage of rice, honey and a fruit".
While I'm at it here's a informative extract from that well known organisation The Amercian Society for Mass Spectrometry.
"Mass spectrometry is a powerful analytical technique that is used to identify unknown compounds, to quantify known compounds, and to elucidate the structure and chemical properties of molecules. Detection of compounds can be accomplished with very minute quantities (as little as 10-12g, 10-15 moles for a compound of mass 1000 Daltons). This means that compounds can be identified at very low concentrations (one part in 1012) in chemically complex mixtures. Mass spectrometry provides valuable information to a wide range of professionals: physicians, astonomers, and biologists, to name a few."
So that explains that then! Actually it's a very interesting website and I recommend people to take a look.