The conventional wisdom advises that wines should be kept at a constant temperature of 55°F (13°C), a humidity level of 70%, and with no vibration, no light and no odor. The science of wine ageing is poorly understood but, in his book Making Sense Of Wine, Matt Kramer offers some good technical explanations for why these requirements are unfounded or, on the contrary, totally justified.
Humidity: according to the common wisdom, humidity is required to keep the cork moist. Matt Kramer argues that it only applies to wood barrels, which were commonly used in private cellars in the 1800s and early 1900s. Wood barrels are porous and a high humidity keeps the wood moist and reduces the amount of evaporation through the pores of the wood. On the contrary, a good cork, compressed to half its size in a bottle, adheres to the glass with a barnaclelike grip. Therefore, the moisture present in the air affects only a tiny portion of the cork, which is too little to change the adherence of the cork to the bottle.
Vibration and movement: traditional thinking contends that continual or chronic vibrations are harmful to wine. In his book, Matt Kramer refers to some studies made at UC Davis by Dr Simpleton, showing that vibrations have little consequence on wine. Dr Simpleton concluded that “the only bad feature about vibration is possibly in dispersing sediments.” Here again, the possibly harmful effect of movement seems to only apply to wine in barrels. Because the wood is porous, oxidation increases when the wine is shaken. This is the famous case of these Bordeaux wines, originally tough and tannic, traveling to the Indies aboard sailing ships and coming back, miraculously fully mature and ready to drink. This started a trend in the 1800s to build devices that would agitate the wine and give it a mature taste called “Retour des Indes” or “Return from the Indies”.
Temperature: The effect of heat on the quality of wine is today pretty well understood. Heat speeds up the chemical reactions within the bottle, causing the wine to age prematurely. For example, a wine stored at 73°F (23°C) will age twice as fast as a wine stored at 55°F (13°C). This could actually be advantageous when cellaring space is a problem. A wine that would need 10 years to mature in a cold cellar, could be enjoyed after 5 years or so if stored in a warmer place. Although some wines are more delicate than others and each type of wine responds to temperature differently, high temperatures can deteriorate wine rapidly. The wine loses its fruitness, gets oxidized and develops cooked aromas.
On the other hand, cold temperatures, which slow down chemical reactions, have little impact on wine, until the wine freezing point is reached, around 27°F (-3°C). The wintertime low, but non freezing, temperatures have no detrimental affect on wine and temperature fluctuation should only be a concern toward the high range.
Light: light, especially sunlight because of its intensity, excites wine molecules. Like heat, it creates chemical reactions that degrade color, aromas and tannins. Regarding artificial light, research has shown that it has a lesser impact. It was found that the wine had to be very close to the source of artificial light and exposed constantly to it to present any harmful effects.
Unfortunately, if your wines have deteriorated because of poor storage conditions, you can always use the Catania Wine Enhancer!
Some Web resources:
• 30 Second Wine Advisor: Cellar-less aging
• Wine, collecting
• The Ideal Wine Cellar
• Storing Wine
• CELLARING ...preserving the flavors while postponing the pleasure...
• How to Cellar Wine
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