Age can be such a delicate matter. Assume a woman is older than she is, especially if she's over 30, and you may get a clip round the ear. Underestimate a child's age and you may get a kick in the shin. Old folks? Well as long as they consider themselves in that category, they may not mind reminiscing about bygone days.

Wine, however, is an altogether different matter. The vintage (the year in which it was made) is an important part of a wine's pedigree and history. For Bordeaux wines, the vintage plays a key role in how much a wine costs upon its release for sale, its stature compared with wines of other chateaux and estates, and, of course, other vintages.

A wine expert should be aware of the weather conditions in different regions. Weather plays a major role in the characteristics of a vintage, as it influences the ripeness of the grapes when they are harvested. Rain during a harvest can spell disaster - grapes absorb rainwater, which can result in watery juice with diluted sugars.

The winemaker spends many hours in his cellar overseeing the vinification process. There's sort-ing the grapes; deciding how long the skins should be in contact with the juice; pressing the must (that's the juice together with the skins and stems) and determining which yeast to use to start fermentation.

Then there's the question of how often the fermenting juices are stirred and the temperatures they are allowed to reach; when to stop fermentation; whether one should filter or not; oak or not (and also whether its new oak or used); how long the wine spends in the barrels or tanks; the clarification process to be used; and when to bottle the wine.

After that, come decisions such as labelling, pricing, marketing and shipping.

With all the effort and care that goes into a wine before it is shipped to faraway destinations, I find it a shame when a restaurant lists the name of a wine without giving the year it was made.

Recently, at one SoHo establishment which calls itself a wine bar (and which was recommended to me by a wine buff), the whites were listed without their vintages. My inquiries were met with a nonchalant, "Well, white wine vintages change all the time, so it's just easier not to put them on the list." Well, the last time I looked, the same rules of time and space applied to both reds and whites.

Taking the bull by the horn, I asked to see the manager, as there obviously was not a sommelier in residence. Upon questioning, the manager told me that he didn't think vintages were important for whites, as they were usually drunk young. He noted that I was the first person to have spotted that the whites were listed minus their vintage - perhaps I was being too picky? I was so indignant at this bit of wine discrimination that I was tempted to leave, but as I was a guest, I had to remain somewhat polite.

My host proceeded to order a bottle of Italian pinot grigio - a safe choice, we thought - with the simple request, "Could you find out what vintage it is please?" The waiter disappeared for 10 minutes only to return with the answer: "2008". Ugh, too old.

Next, we asked for a New Zealand chardonnay. This turned out to be a 2006. Unusually for a New Zealand wine, rather than a screwcap it had a cork, which was an uninviting shade of brown. We declined the bottle.

At this point we had spent more than 20 minutes trying to order a bottle and we were, by now, thirsty (I was even contemplating a beer). But we tried again, this time going for a German riesling. Surprise, surprise (third time lucky, I guess), it was a lovely 2009 Kabinett from Mosel, which turned out to have lovely fruit and acid, with a crisp minerally finish.

The moral of the story? A good wine list should have the vintages on it. It saves time and is an important part of choosing a wine. Some whites are meant to be enjoyed in their youth (think sauvignon blanc, pinot grigio) while others can be more interesting when they've had a bit of time in the bottle. I'm sure the poor sommelier will be shown mercy if he's erred in not updating a wine list immediately when a new vintage is delivered without prior notice.