Grapevine

Professional winemakers and savvy consumers are catching on to the Clef du Vin, or "wine key"—a metal dipping stick that comes in pocket, bottle and glass sizes and which simulates the effects of the passage of time on wine. Immerse the end of the Clef du Vin into a glass of wine, and the wine's flavor will change as if it had been aged one, two or even 10 years longer—thereby enabling the taster to assess the cellaring potential of the wine in an instant, a capability that has made the Clef du Vin the hottest (and snobbiest) accessory on the tasting circuit.

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Developed in France by top sommelier Franck Thomas and enologist Laurent Zanon, the Clef du Vin's alloy (the combination is a trade secret) acts as a catalyst to speed up the oxidization process. The metals are precisely gauged so that dipping the tool into a glass of wine for one second will mimic the effect of a year's aging. Dipping it for two seconds simulates the effect of two year's cellaring, and so on. The key does not leach into the wine, and therefore is not harmful to drinkers.

Experts caution that the Clef du Vin will not magically transform a harsh vin de table into a grand vintage. (You can ruin a good wine by leaving the instrument in the drink too long.) What it can do is help determine which vintages are worth waiting for, and for how long. Wine goes through stages of oxidization, from fermentation and bottling to total oxidization, when it becomes too old to consume. In between, it reaches periods of equilibrium when it is perfect for uncorking. The Clef du Vin helps predict when those periods will fall—and with 95% accuracy, according to experts. In other words, with the Clef du Vin, you'll get a much clearer picture of what being "aged to perfection" is all about.