Americans can’t decide which they love more: red wine or white wine. Fifty-one percent of the wine they buy is red, but the varietal they drink the most is chardonnay, a white wine. They drink a lot of white wine in Nebraska, Kansas, and Iowa, and a lot of red wine in North Carolina, Mississippi, Michigan, and Pennsylvania, but the other states drink both in roughly the same amount. If you’re like most Americans, sooner or later you’ll find yourself with both red and white wine bottles in your home and only a fuzzy idea about how to keep them both fresh. Do you store them apart or together? Do you need one fridge or two? A dual or single zone wine cooler? Fortunately, these questions have a simple answer. There’s no trick to storing red wine vs. white wine, just a god appreciation of their chemistry and a careful balance of vibration, humidity, light, and heat.
A bottle of wine is made up of over a thousand different chemical components reacting and interacting with one another. The most important are acids, alcohol, esters, and tannins, the ingredients responsible for your wine’s taste.
|Acids||Tartaric, malic, and citric acids come directly from the grapes. Determine how tart your wine is|
|Alcohol||Produced by yeast during fermentation. A high level of alcohol diminishes the sweetness of your wine|
|Esters||Flavor compounds created by the interaction of acids and alcohol. Responsible for the flavors in the wine’s aroma, such as pepper, vanilla, plum, almond, mint, chocolate, coffee, caramel, cinnamon, and smoke|
|Tannins||Come from grape skins and oak barrels. Bind to proteins in your saliva and give wine its dry taste|
Wine is not a stable solution. Its components continue to react and interact with one another longer after the wine has been fermented and bottled. Under the right conditions, these reactions can improve the wine’s taste, texture, and aroma. Under the wrong conditions, it can ruin it.
There are four factors that determine how well a wine ages: vibration, humidity, sunlight, and heat. Some have a bigger impact than others, but each plays a role and none should be neglected.
|Vibrations||Accelerate chemical reactions. The faster molecules are moving, the more energy they have when they collide with one another and the more likely they are to initiate a chemical reaction. Vibrations should be kept to a minimum|
|Humidity||Corks need to stay humid in order to keep the wine safely sealed. When corks dry out, they shrink and crack, which lets oxygen seep into your wine and ruin it. Always keep your wine bottles at 50-80 percent humidity|
|Sunlight||Sunlight, especially UV rays, breaks down amino acids in wine and create volatile sulfur compounds. In white wine, it also creates a coppery haze. Always store your wine someplace dark. The good news: fluorescents or LEDs emit light in a narrower range and don’t damage your wine the same way.|
|Heat||Drives chemical reactions. The more heat you add to a system, the faster it evolves. Storing wine at high temperatures causes it to age faster. Cool, stable temperatures are best|
Though wines age faster at high heat, they don’t all age the same way. Each component requires different temperatures to start reacting. Tannins polymerize at lower temperatures than sugars ferment, and acids and alcohol react at different temperatures too, which is why heating your wine isn’t a good way to speed up the aging process. While reaction rates will increase, they won’t increase in unison. Some will double or triple, while others will hardly be affected at all. Imagine taking a bottle of wine aged ten years and mixing it with a bottle of wine aged ten months. The resulting mish-mash is exactly what happens when you heat a bottle of wine too far. If you can, always keep your red wine at 55°F and your white wine at 45°F until you’re ready to drink it. At those temperatures, all the reactions will proceed at roughly the same place and your wine will be safe from spoilage.
High temperatures are bad for wine, but temperature fluctuations are even worse. When a bottle of wine heats up, the volume of the wine inside increases. Since wine bottles are sealed, the extra volume exerts more pressure on the bottle, especially the cork. It’s the weakest part of the wine bottles, and if the pressure climbs too high, it will eventually break the seal around the cork and let oxygen into your wine. If you’ve ever left a bottle of wine someplace, only to find the cork push out slightly when you return, this is what’s happened. If you leave the wine as the temperature starts dropping again, the wine’s volume will decrease and pull the cork back into the bottle, sucking in more oxygen. This cycle is terrible for wine. Oxygen and oxidation are bad for your wine. Oxygen is what turns wine into vinegar. It feeds bacteria that produce acetic acid, one of the main components in vinegar. It also produces aldehyde, which turns the wine from brown to red. This process is so damaging, that some experts claim you’d be better off storing wine in a warm spot with a stable temperature than a cool spot with an unstable one.
Storing Red Wine vs. White Wine
Even though red wines and white wines react to vibrations, humidity, sunlight, and heat in exactly the same way, their different level of tannins means that sometimes they’re better off being stored at different temperatures. Tannins play an important role in aging. They’re a buffer against oxidation. They absorb bind to oxygen molecules and prevent them from being absorbed by residual bacteria or binding to other molecules. Tannins mostly come from grape skins, grape seeds, and oak barrels. Because they’re fermented with all three, red wine has a much higher tannin level than white wine. White wines may also absorb some tannins if they’re aged in oak barrels, otherwise they’re mostly absent because they’re fermented with just the juice. Tannins are the reason why red wines age so much better than white wines. Some reds can be kept for up to 30 years without spoiling, while white wines rarely last for more than seven or eight.
Most wine is sold ready-to-drink and doesn’t benefit from aging. If you are planning on keeping a bottle of white wine for a long time though, maybe to celebrate a special occasion, then the best way to keep it safe is to store it at 45-50°F in order to slow the chemical reactions inside. It’s the only way to preserve its flavor and extend its lifespan. By depriving the system of energy, you’ll slow oxidation to a minimum. You won’t stop it completely. Some chemical reactions will continue and the ones with a low heat threshold will happen fastest. High threshold reactions will still occur, just much more slowly. Some of these are beneficial, so you don’t want to lower the temperature below 45°F if you can help it. You want the reaction rate to be enough to slow oxidation, but not so slow the wine stops aging completely.
Another reason why red wines and white wines are stored at different temperatures is because reds and whites are meant to be served as different temperatures. White wines have a higher proportion of esters and flavor compounds than red wines. These aromas accumulate in the head of the wine glass and heighten the wine’s fruity flavors best when they’re served at 49-55°F, while the tannins in red wine react with your taste buds much more strongly when they’re consumed at 62-68°F. Keeping your wines in a dual zone cooler lets you store them each at their optimal temperatures, so they’re always ready to be served when you’re ready to drink.