Roger Corder is one of those enviable people, doing wine testing as a job. But Corder does not work for a wine magazine or the Guide Michelin. He is a researcher in the cardiovascular field at the London William Harvey Research Institute. With his publication in the Nature journal regarding the beneficial effects of red wine on the endotheliar function in 2001, he essentially contributed to red wine becoming a trendy drink and the considerable rise in prices as well.
Southern France and Sardinia are the fountains of youth in Europe
Already his first work was just as simple as brilliant: The scientists had dripped different types of red wine on 28 endotheliar cell cultures of beef to see, what would happen with the endotheliar function. The result was, the red wine suppressed the synthesis of the strongly vasoconstrictive potent endothelins, mainly when the content of polyphenols was very high. Polyphenols are some of the coloring- and tanning agents in red wine. They are the reason, why some red wines have such an intensive red color. "Winner" of Corder's test series then was a Madiran "Cuvée Charles de Batz", a red wine from Southwest France with a high portion of Tannat grapes. Since this observation, Corder and his colleagues have traveled half of the world of wines to collect red wines for are more thorough analysis.
The target was to find out, what exactly those polyphenols are which protect the blood vessels. In a new publication in the Nature journal, the scientists have published the latest results of many years of their work. According to this, the so-called Procyanidine are the ones blocking the synthesis of the endothelins most effectively, thus being the candidates for the explanation of the "French Paradox". The French Paradox describes the phenomenon that in Southern France, despite the food being rather problematic for the blood vessels, less myocardial infarcts occur than anywhere else.
In retort wines, the polyphenols prefer staying in the core
One of the advantages of the Procyanidine-hypothesis is, that those polyphenols actually are found in an amount worth mentioning: "Other substances as for example Resveratrol were taken into consideration as an explanation for the French Paradox. But the problem always was, that you would have to drink several hundred liters of wine to achieve the concentration as effective in the experiments" explains Corder. It is different with the Procyanidines: "They are available in a concentration of up to one gram per liter, which means, one glass of red wine a day should be enough", calculates the scientist. But: Not every red wine has it. Because the content of Procyanidines was extremely varied in the wines examined by Corder.
Since polyphenols are found mainly in the cores and the paring of the grapes, roughly the rule applies, that wines pressed longer contain more polyphenols than shorter pressed wines. The reason: the substances of contents of the cores "reach" the wines only after about 10 days. Industrially pressed wines have just about four to five days, enough to make the wines red, but not enough to protect the Endothel.
Grapes out in the sun – out for health!
But not just the length of time of the processing is relevant. The grapes themselves play a role as well. For example the Tannat grape, related to the Cabernet. Sauvignon, is rich in Procyanidines. That explains, why wines from the Southern French Departement Gers, where the above mentioned Madiran is originating from, showed excellent results in Corder's tests: They are pressed relatively long and are very rich in Tannat grapes. "Those wines have a ten-time higher biological activity than modern wines from the new world" says Corder. And a third factor seems to add a word or two as well: the sun. Another winner in Corder's wine competition was Sardinian wine from the province around the town of Nuoro, which actually is famous for the longevity of its inhabitants. You will not find any Tannat grapes here, but several unknown vine varieties, mainly the Cannonau.
The remarkable in the central Sardinian wines is the relatively high crop growing in the mountains. "We known, that UV light can influence the polyphenol synthesis in the grapes", says Corder. UV light, the vine variety and a long pressing – those factors can be essential, whether a red wine is good for medical purposes or not. One of the central messages of Corder: That little glass of red wine in the evening is healthy, does not always apply. After all it depends on, what you sip…