Wine cooling is much more than just a method of preservation: it's also a continuing story of evolution. The distinction may seem small, but it's an important one if you're to understand the role that bottle storage temperature plays in the aging and maturing of wine.
Better tasting through chemistry
As any wine drinker knows, the taste is a product of chemistry. A common misconception about storage is that its sole purpose is to prevent the spoiling of a wine's given taste. Yet like the chemical processes that create it, the taste isn't a static thing. Wine changes over time in response to its environment - in particular, to temperature, humidity, light, and bottle position and movement. The goal of climate-controlled storage isn't just to "freeze" the taste in time and prevent it from spoiling, but to encourage desirable chemical reactions and prevent undesirable ones, thereby yielding a product of greater complexity and maturity.
The best wine temperature storage range
The most common temperature storage question is fortunately the easiest to answer: 55°F (13°C) is widely considered to be the best temperature for storing bottles, though some experts advocate a degree or two cooler. A range of 50°F to 55°F (10° to 13°C) is optimum for many types. The lower the temperature, the slower the speed at which chemical reactions can occur, and the more gracefully it is able to age.
Some white wines can be stored around 45°F, e.g. Champagne, sparkling, and medium-to light-bodied whites. Speaking generally, however, excessively cold storage may inhibit the maturation, plus may expand and damage the cork. Outright freezing will invariably ruin the wine and/or break the bottle.
When good wines go bad
Here's where things get tricky: it's not just the temperature at which a wine is stored that matters, but also the fluctuations of that temperature and the reactions that they trigger. An increase in oxygen and decrease in sulfur dioxide are two of the main processes that harm the taste and color of both white and red.
Oxidation is the result of a wine's rate of oxygen uptake, which increases when it exposed to air or higher storage temperatures. White wines are generally more vulnerable to oxidation than reds. Signs of oxidation include flat taste, a dark or brown color, and a sherry-like odor.
The speed of chemical reactions in wine increases exponentially as its storage temperature rises. For example, Principles and Practices of Winemaking, one of the leading reference books, features a temperature storage chart which shows the relative rate of chemical reactions at various temperatures, using 50°F as a baseline. An increase to 59°F increases oxygen uptake by 2.76%, and the oxygen uptake rate at 77°F is 18.9% faster. Oxygen uptake at 95°F is 114% faster than at 50°F.
Daily cyclic variation in storage temperature is another potential concern. Thermal expansion and contraction causes variations in bottle pressure, which can lead to cork movement or "headspace venting" and the introduction of air into the bottle.
When good wines get better
Not all wines significantly improve with age. In fact, most that an average collector purchases are likely best consumed within six months to two years. So-called "big" red wines such as Cabernet Sauvignon and Syrah are likely to age well due to their high phenol levels. Highly acidic whites may also have greater aging potential. Factors that determine whether it has aging potential include its grape variety, vintage, and region. In most cases, slow aging in a temperature-controlled cooler refrigerator should give any bottle its best chance of reaching its full potential.