Wine seems, at times, to be the only food that not only improves as it ages, but is designed to be aged for extended periods.
Aging a bottle of wine leads to complex chemical reactions that can improve qualities of wine such as flavor, aroma, and body until excessive oxidation begins to turn the wine.
To understand how aging can make wine taste better, it is important to understand the effects of aging on wine and how wine is aged. It is also important to know which wines should be aged and for how long, as this differs based on the natural chemicals found in each wine.
What is Wine Aging?
In terms of wine, aging refers to any additional chemical reactions that take place after fermentation but before the wine is consumed. Most wineries will age their wine for a time after fermenting and bottling, but wines can be aged by wineries or consumers for a longer time to increase the benefits of aging.
Wines are traditionally aged by sealing them in a wood or metal barrel and leaving them in an aging cellar or chamber to develop. This not only prevents the wine from becoming contaminated or spoiling, the environmental conditions of specialized aging rooms are designed to improve the aging process.
Most aging rooms are cool, dry areas with little light expose, as extremes of heat, moisture, and light can cause adverse chemical reactions in wine. This is why cellars are traditionally used for aging, since they are usually far from light, cooler than upper floors, and easier to keep dry, provided the aging containers used are elevated off the floor.
Wineries will generally age wines to a state of maturation, this being when the benefits of aging first begin to manifest and create a more balanced wine. Maturation for most wines occurs within the first two years, but some vintages are, or can be, aged for longer to further improve their flavor.
How does Aging Effect Wine?
There are a number of chemical reactions that occur in wine during the aging process that impact the qualities of wine. While each of these processes has unique benefits for wine, the merging of these reactions through aging that causes the process to improve the flavor and body of wine.
One of the main processes responsible for the development of aging wine is known as malolactic fermentation. This occurs when malic acid, which is a natural compound found in wine grapes, is fermented into lactic acid, meaning that is undergoes a natural process that breaks down and converts malic acid’s chemical structure.
Malolactic fermentation gives wine a smoother, mellower quality, as malic acid is highly astringent and acidic in taste, creating an equally stinging flavor in wine. By removing this acid and replacing it with the far milder lactic acid, aging creates a richer, more pleasant body in the aged wine.
The natural flavors of wine will also begin to develop as remnants of chemicals like sugar and malic acid are fermented. This causes flavonoid phenols, chemicals that create different flavors and textures, to blend into new polymers creating different tastes and textures in the wine as it ages.
These flavors can be particularly strong if the wine is aged in a wooden barrel, such as oak wood, which releases additional chemicals into the wine. Oak wood in particular releases tannins that create a full, dry texture, while adding sweet notes of vanilla and caramel for an all-around creamier wine.
One chemical that is important not only to wine aging but preservation and flavor is tannins, a natural compound found in wine grapes and oak wood. Tannins have a naturally dry and astringent taste when young, but as they mature through aging they dissipate through the wine to create its body and bouquet.
Flavor is also effected by oxidation, or the process of oxygen gas passing into and out aging barrels, often through porous wood like oak since metal barrels are completely sealed. While oxidation can ruin a bottle of wine, under certain circumstances it creates a nutty, savory flavor similar to sherry wine that can be quite pleasing to the palate.
While not the same as taste, aromas and bouquets often have a strong effect on how a wine is enjoyed and how it impacts the palate. As wines age in sealed containers, their trapped scents begin to mingle the same way its flavors do, with chemicals breaking down and being made into new polymers.
As wine ages, its bouquet also grows more complex and nuanced as different chemicals and flavonoids balance out while trapped in the aging barrel. This means that aged wines often have a more robust and pleasing scent, as opposed to younger wines that may be more immature or chemically imbalanced.
Which Wines Age Better?
When looking you are looking to age a bottle of wine, it is important to remember that the vast majority are not mage to be aged at all after they are bought. In fact, almost 95% of wines are not designed to last beyond five years with most of that group not lasting long beyond a year or two.
But that last 5% of wine bottles can be improved immensely with proper aging, and it is important to know how to recognize them. Primarily so that you do not waste your money buying a bottle that goes bad in a year. To this end there are four factors to look for in aging a wine, acidity, tannin levels, sugars, and alcohol content.
As wines age their acids ferment and mellow, creating new compounds with different flavor and aroma profiles. For this reason it is better to pick a more acidic wine when looking to age, since this means the wine will have more chemicals to break down to create a more balanced and pleasant flavor.
Polyphenol compounds like tannins are excellent preservatives and can change the flavor of wine over time, so highly tannic wine ages better. Generally red wines are more tannic since they soak in the tannin rich seeds, skins, and stems of grapes, but oak aging barrels can also add tannins to wine.
Sugar can also act as a preservative, think of long-lasting jams, jellies, and preserves that are rich in sugar, so wines with a higher sugar content also last longer while aging. If you are looking for a sugary wine to bring home consider looking for a dessert wine such as sherry or port.
Finally, alcohol content can work in both directions, as a high alcohol content can help preserve and stabilize wine for long term storage, while at the same time a very low alcohol content means less alcohol to break down the wine. The best advice here is to aim for the more extreme ends of the spectrum, bellow 11% and above 15% ABV.
Beyond chemical components, be sure to look for more experienced and established wineries with a history of quality winemaking. New winemakers, especially amateurs, may not understand the complex chemical processes that go into wine making, and could end up selling you a bottle that only spoils over time rather than maturing.
Given these qualities, as a general rule more tannic red wines tend to age better than white wines. If you are looking for a well-aged red wine consider classics like Cabernet Sauvignon and Merlot, as well as Nebboilo, whose high tannin levels allow the wine to be aged for decades at a time.
White wines may not age as gracefully or as long as red wines, but there are still a few vintages worthy of aging. Chardonnay, Savatiano, and Arinto maintain the right chemical balance not only to survive aging, but to improve with a brief stint on the shelf.
It can be perplexing to try and understand the concept of aging wine, as most foods do not improve with age.
Wines improve with age thanks to a number of chemicals and reactions, such as acid fermentation and tannins that not only preserve wine but improve it over time. Generally red wines are richer in these chemicals, making them better to age, but there are some white wines that can be improved by a bit of patience and proper storage.