How often have we overlooked the fact that wine lives in the bottle and ages over time. As in the case of food, high ambient temperatures can hasten its development and even cause a wine to spoil.

Temperature

Swedish Nobel Prize-winning chemist Svante Arrhenius determined that for every 10°C increase in temperature, the speed of an average chemical reaction in wine increases between 50% and 200%. Wines age faster at higher temperatures.

The upper end of acceptable wine storage temperature is around 18°C. Store wines at much higher temperatures and they begin to develop prematurely. A red wine might reach its peak within a year instead of a few years. This may sound like a bonus – being able to drink wines before “their time”. However, there is a price to pay for wines aged prematurely. Red wine will take on a “cooked” character – similar to the taste of boiled red wine. The colour of white wine changes to an unattractive brown and the wine will taste oxidised.

What if you kept your wines really cold – at beneath 10°C? At these lower temperatures, the chemical reactions in wine are so slow, it hardly ages.

“What is the optimal temperature then?” asks reader JT who has set up a walk-in wine cellar at home.

The recommended optimal temperature for wine storage depends on the type of wine. White wines appreciate cooler temperatures – aficionados suggest 12°C as an optimal temperature. However, collectors maturing red wines might prefer 14°C. For white and red wines, 12°C is best.

Temperature fluctuations

Temperature fluctuations can be damaging to wine. When I began with a modest collection of wine, I believed that I could store wines long term easily in a dark corner of my wardrobe. The wardrobe was in an air-conditioned bedroom. When the air-conditioner was on during the night, the room was cooled to 16°C. During the day, when I was out of the room, the air-conditioner was switched off, and the room warmed up to about 20°C and sometimes more. The premise was that the average temperature would be at 18°C.

About a year later, to my dismay, I found that the wines were not very palatable – I knew this because I compared them with the same wines that my friend had stored in his wine fridge. I then questioned the fact that in Europe, the natural underground cellar temperature changes according to the seasons. However, an expert agreed that temperatures do change. But with those underground cellars, the temperature fluctuates about 2°C around the average once per year. In the case of my wardrobe cellar, the fluctuations were at least four degrees daily!

The temperature swings in my wardrobe cellar had an adverse effect on the wine. As the wine warmed up, it expanded. The cork moved out slightly and in some instances a little bit of the contents (the wine itself as the bottle was stored properly on its side) pushed past the cork. As the bottle cooled, the wine contracted, drawing air into the bottle. I lost 12 bottles of wine. What I gained, however, was an invaluable lesson in storing wines properly.

If you are thinking of getting the domestic refrigerator to do double duty, note that it cannot do the job of maturing wines in the long term for the following reasons:

• Fridges store food at around 4°C. This is too cold for wine.

• The compressor turns on and off at intervals and is a source of vibration.

• Whenever the fridge is opened – when it is loaded up or food is removed – this causes temperatures to change.

• Food requires a dry environment and the domestic food refrigerator is designed as such. The dehydrating nature of the appliance will not be good for keeping your wine corks moist and plump. Eventually, the cork “seal” will be bridged.

Easiest solution

The best way to store wines is in a special wine cave/chiller/cooler. This is because it offers temperature control. Some units are fitted with humidity controls. And certainly, most brands feature isolated cabinets (against compressor vibration and light). Where glass doors are used, they are anti-UV treated. Expensive models will even incorporate air exchange/filters.

Take heart, if a wine fridge seems a bit extravagant, you can always store cosmetics and chocolates alongside your wine but make sure they are in their own sealed boxes.

Ed Soon is a qualified oenologist and has run wine shops and worked as a winemaker in various countries. He now writes and teaches about wine around Asia.