OLD VINTAGES : Bordeaux researchers have perfected a method of dating the glass of wine bottles. A step further in the fight against fraud :
Last week a couple from the Bouches-du-Rhone region were arrested for having sold, via the Ebay auction website, 200 bottles of so-called Grand Cru French wines which turned out to be fancy bottles filled for the most part with very ordinary wine...
Visually, it is difficult to tell a great wine from an ordinary one and so the temptation to falsify is great.
"Especially as the market for old vintage wines is thriving," says Angélique de Lencquesaing, one of the founders of the website www.idealwine.com in 2000. This company which employs 12 people and is based in the Paris area, provides a service of quoting values of vintage wines. "Our experience helps to authenticate bottles : glass, scanned labels, capsules pierced by syringes to top up wine levels...But these new techniques can provide a plus only if the price remains acceptable", she explains.
Important discovery : In today's select market for old wines, a spectacular discovery has just been made by researchers at the Bordeaux Centre For Nuclear Studies (CNRS/Bordeaux 1) in Gradignan. This centre, employing a staff of one hundred, has been studying composition and structure of matter since 1967. The research team, led by Hervé Guégan, has finally perfected, after two years of work, a unique system of dating the glass of a wine bottle by subjecting it to a beam of ions produced by the particle accelerator based at the Gradignan centre. "Thanks to our analysis of over a hundred glass bottles containing Bordeaux wine from the 18th century onwards, we now possess a database of all the different techniques used by glass-makers in the past. For example, since 1957 manganese is no longer a componant in glass", explains Hervé Guégan, who is the head of Arcane, the department for technological transfer for the Gradignan laboratory. Mr Guégan's mission is clearly to communicate the value of their discoveries to the private sector.
In order to complete this database which initially enables the researchers to define time slots of fifteen years, Hervé Guégan analyses bottles of wine from ten or so of the greatest Bordeaux estates, from the most valued vintages (1890, 1892, 1929, 1945, 1961, 1982, 1990, 2000,.).
Some of these wines sell for astronomical prices in auctions.*
In its capacity to confirm the authenticity of age and provenance of these bottles, Arcane has signed a contract with "The Antique Wine Company", the London specialist in old, rare wines. In November, a new company named Vincert SARL will deliver authentification certificates to traders and buyers alike who wish to allay any doubts about rare bottles. This certificate should be worth approximately 500 euros. In the art world where such certificates guaranteeing authenticity rarely exceed 5 to 10% of the product's value, this service is aimed at a market for bottles worth over 5,000 euros a piece...To give an idea of price range, Idealwine values a Lafite Rothschild 1982 at 1,600 euros per bottle and a Mouton Rothschild 1945 at 7,000 euros.
Checking the wine : This new dating method for glass is an additional weapon in the arsenal of tests available to professionals and the government in the war against fraud. In 2002 researcher Philippe Hubert, also based at the centre in Gradignan, developed a technique which detects the presence of the chemical substance Cesium 137 in wine. This chemical is a result of nuclear weapons tests which began in 1945.
Wine definately has a memory, as proves the correlation between the quantity of Cesium 137 it contains (which is analysed without opening the bottle) and the period during which the wine was produced. The only drawback with this method of analysis also used to check the provenance of prunes and mushrooms, is that one cannot go back farther than the year 1950. Research continues and tomorrow we may see the use of carbon for dating.
César Compadre
doc@sudouest.com
S.O. 09/09/08
Translated by Maxine Colas.
*See the book "The Billionaire's Vinegar" by Benjamin Wallace.