ARCHAEOLOGICAL CHEMISTRY—EXPLORING HISTORY WITH CHEMISTRY - Chemistry: Notable Research and Discoveries - page 183

separates components of a mixture by pumping a solution to be studied
through a column of absorbent material. Some of the components of
the solution travel farther along the column than others, and scientists
can isolate the separated components. Guasch-Jané and her colleagues
discovered a substance, syringic acid, which derives from the grapes
used to make red wine. As described in a news release posted on April
3, 2005, at Science Daily, this was the first identification of the color of
wine in ancient Egyptian residues. In later experiments, the researchers
also found evidence for white wine in Tutankhamen's tomb.
Written records of many ancient civilizations, beginning a few
thousand years ago, document the use and production of beverages. But
archaeological chemists have pushed the date of the earliest such pro-
cesses further back than the historical records go. A team of researchers
led by Patrick E. McGovern, at the Museum Applied Science Center
for Archaeology at the University of Pennsylvania Museum of Archae-
ology and Anthropology, performed chemical analyses of substances
that had been absorbed into pottery belonging to Chinese villages of the
early stone age. The pottery they studied range from 7,500 to 9,000 years
old. Using solvents such as methanol, chloroform, and hexane, along
with heat or sonication (high-intensity sound waves), the researchers
extracted organic material from the pottery pieces. They identified the
materials by a number of different analytical methods, including chro-
matography, mass spectrometry, and isotope analysis. Components of
these materials, such as tartaric acid and alkanes (a type of hydrocar-
bon), match the composition of wine made from grapes or rice.
The researchers published their findings in a 2004 paper, “Ferment-
ed Beverages of Pre- and Proto-historic China,” in the Proceedings of
the National Academy of Sciences. They concluded their paper with the
following observation: “The ancient chemical evidence now enables the
later beverages to be traced back as far as 7000 b.c.e. and reveals how
Chinese beverage-making developed over the millennia. Our results
also illustrate how both religious ceremonies and activities of everyday
life in which these vessels were used, and still important in modern Chi-
nese culture, likely have their basis in prehistory.”
The Museum Applied Science Center for Archaeology conducts
studies such as these to expand the knowledge of ancient cultures by
applying rigorous scientific techniques. More information about this
research center can be found in the following sidebar.