Q: I have noticed while shopping that a few wine bottles did not have a year listed on their labels. Because I like to store wine according to its vintage, this is frustrating — and puzzling too. Could you clarify this?
—Jan Truty, Schaumburg
A: Wineries don't have to put a vintage year on the label. This omission is most common with Champagne and sparkling wine makers, who blend wines from different years to create an unique "house" style that varies little over time.
A vintage year on the label "indicates the year in which the grapes were harvested," according to the Alcohol and Tobacco Tax and Trade Bureau of the U.S. Department of the Treasury. But that doesn't mean a bottle with a 2010 vintage on it is filled just with grapes harvested in that year.
Federal regulations allow wineries who label their wine with a state of origin ("California," say) to put a vintage year on a bottle if 85 percent of the grapes are from that year. If the wine uses a viticultural designation or appellation (like Napa or Sonoma), the percentage rises to 95 percent of the grapes must be from that vintage year.
Unfortunately, the quality of a wine can't be reliably judged by whether there's a vintage on the label.
"Although it's often assumed that a vintage wine is one of superior quality, that's not necessarily true,'' notes "The Wine Lover's Companion." "Some vintages are simply considered better overall than others. That's because the quality of the harvest varies from one year to another.
"In addition, an individual wine may be better or worse than others of a particular vintage because of the originating vineyard's microclimate or because of the winemaking process it underwent."
Vintage years, the "Companion" concludes, should be used by consumers "only as a general guideline."
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