What does a wine’s vintage date mean for its quality?

I noticed restaurant wine lists and some wine reviews that catalogue wines without a vintage date. Is that information no longer important to know?

The vintage date stated on a label declares the year in which the grapes were harvested. By indicating how old a wine is, a vintage can help consumers decide when (or not) to drink a wine to experience it at its best or, more importantly, whether or not to purchase it at all.

You might not care to splurge on an expensive wine from Burgundy or Bordeaux, say, if it’s from a cool and wet vintage that yielded substandard grapes. Buying a wine from a vintage that’s been declared as good or outstanding is a safer bet as the raw materials were present to produce wines of the best possible quality and style. A better vintage doesn’t guarantee the wine will live up to the expectations or lofty price, but it does narrow the odds.

Likewise, a vintage date can signal a wine that’s past its prime. For instance, you wouldn’t wish to drink a bottle of Marlborough sauvignon blanc from 2011. Most tasters like their sauvignon blancs in a younger, fresher style – “bottled as close to yesterday as possible,” in the words of one New Zealand winemaker I interviewed years ago – not mellower and richer with more complex flavours.

The majority of wines produced nowadays are best consumed when young. Some wines are made in a style that will benefit from extended aging in bottle, during which time they develop more complex aromas and flavours. Knowing more information about how they were made is crucial to understanding when an age-worthy wine might reach its potential.

The vintage on a wine label is testament that the liquid inside the bottle came from a crop of grapes that was affected by its growing season and handling.

Climate influences the taste of a wine through its effect on the grape. Hotter and drier climates like south Australia, Southern California and South Africa tend to produce wines that are less variable from year to year. Grapes in warmer climates typically ripen to full maturity. But even in these more uniform areas, the grapevines’ and fruits’ reactions to sunshine, rain, cold and wind influences during the growing season will affect the end product of any given vintage.

Thanks to advances in grape-growing and winemaking, there’s much less bad wine produced even in more marginal climates. Shared information from schools of oenology and viticulture and other research institutes has helped the winemaking industry cope with the vagaries of mother nature, but even casual consumers may sense a difference from wines made in a sunny and warm vintage compared to “classic” conditions, to use the term French producers commonly employ when forced to market wines from an average growing season.

In places such as Canada’s largest wine-producing regions, Niagara and the Okanagan, weather can vary considerably from year to year, which has significant influence on the quality of the grapes. On occasions when we enjoy a particularly sunny and dry summer, odds are high that the vintage will probably be good. Knowing the vintage and what the growing conditions were like ultimately help consumers know what to expect before committing to the purchase.

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