“Fingerprinting” of Washington Wines
Shirley Orellana and Anne Johansen*
*Chemistry Department, Central Washington University, MS
7539,
400 E. University Way, Ellensburg, WA 98926
(anne.johansen@cwu.edu)
Washington State is the second-largest premium wine producer in the United States, harvesting over 200,000 tons of grapes per year and producing 16 million cases. With a total economic impact of ~$5 billion, wine fraud could have a significant negative effect on the industry. In an effort to reduce this risk, here we explore the use of advanced analytical techniques to “fingerprint” and build a database of WA wines that could classify each wine to its geographic origin. Focus is on the analysis of inorganic, chemically stable, and thus conservative tracers that remain constant in bottled wine, independent of aging. These techniques are analogous to those used by the European Union to mitigate against fraud and consist of the analysis of trace metals and isotopic compositions. Of particular importance in this context is the extraordinary capability of our recently acquired Inductively Coupled Plasma Triple Quadrupole Mass Spectrometer (ICP-QQQ), with which 66 elements can be quantified reliably at sub-parts per billion (ppb) levels, including relative isotopic abundances of some elements. Furthermore, with a different instrument, we will analyze the isotopic composition of water in wine, as it provides the geospatial origin of water. Statistical analyses will be used to establish significant similarities and differences among wines within the region and with selected wines from other parts of the world. Since measured parameters are controlled by vineyard soils and winery procedures, they should allow unique identification of region once a database is established.
Funding Support: Central Washington University