Here are some highlights about cellaring and aging from a recent Robin Garr newsletter.
• Most wines don't age. This point is simple but often overlooked. Probably 99 percent of all the wines made in the world, including virtually all inexpensive wines, are never better than when they are first bottled. Only a tiny fraction are made to age, and an even smaller number require aging. Look to the most "noble" red grapes - Cabernet Sauvignon and the Bordeaux blends, Syrah and Shiraz, top Italian red grapes and, of course, the finer Pinot Noirs, for your cellar candidates. Age worthy white wines are even more rare, although Riesling and Chenin Blanc and a few exceptional Chardonnays will gain from aging. Sweet and fortified wines, particularly Port and late-harvest whites like Sauternes, will also age into a golden maturity.
• Aging wines need care.. Even the most cellar worthy wines won't thrive if you keep them under poor conditions. The kitchen cabinet or other warm place is worst. A wine rack at room temperature (or a wine-shop rack in the open store environment) is slightly better, assuming horizontal storage position and air-conditioning. But for long-term cellaring, as we're discussing here, keeping find young wines for 10, 20 years or more, you must have a temperature-controlled cellar that holds the wines horizontally at a constant temperature close to 55F (13C), the approximate temperature of natural caves.
• What happens when wine ages? Again assuming an age worthy wine kept under excellent conditions, the primary reaction that takes place over time involves changes (technically, polymerization, primarily) in the organic compounds called tannins that occur naturally in the red grape skins and seeds as well as the oak barrels in which the wine may be fermented and stored. As time goes by, the wine's color may change a bit, taking on more brownish or golden colors or, among reds, sometimes becoming lighter. The youthful fruit aromas and flavors (sometimes called "primary") and the aroma characteristics associated with wine making - yeast and oak, for example - (called "secondary") will begin to fade somewhat, ideally remaining present but taking a back seat to the intriguing, complex earthy flavors ("tertiary"), which may evoke a wide range of attractive aromas and flavors from toast or leather to woodsy or spicy scents. At the same time, the changes in tannins reduce or remove the rough astringency associated with young tannins, replacing this with a more smooth and mellow texture. And all this assumes that the young wine offered a good balance of fruit, acidity and tannins in the first place. A youthful wine that's out of whack and imbalanced isn't likely to achieve greater grace and elegance with age.
Age your noble wines gracefully!