What wine can age?
In general, wines with a low pH (such as Pinot noir and Sangiovese) have a greater capability of aging. With red wines, a high level of flavor compounds, such as phenolics (most notably tannins), will increase the likelihood that a wine will be able to age. Wines with high levels of phenols include Cabernet Sauvignon, Nebbiolo and Syrah. The white wines with the longest aging potential tend to be those with a high amount of extract and acidity. The acidity in white wines plays a similar role that tannins have with red wines in acting as a preservative. The process of making white wines, which includes little to no skin contact, means that white wines have a significantly lower amount of phenolic compounds, though barrel fermentation and oak aging can impart some phenols. Similarly, the minimal skin contact with rosé wine limits their aging potential.
After aging at the winery most wood-aged Ports, Sherries, Vins doux naturels, Vins de liqueur, basic level Ice wines and sparkling wines are bottled when the producer feels that they are ready to be consumed. These wines are ready to drink upon release and will not benefit much from aging. Vintage Ports and other bottled-aged Ports & Sherries will benefit from some additional aging, as can vintage Champagne.In 2009, a 184-year-old bottle of Perrier-Jouët was opened and tasted, still drinkable, with notes of "truffles and caramel", according to the experts.
Wines with little to no aging potential
A guideline provided by Master of Wine Jancis Robinson
- German QBAs
- Asti and Moscato Spumante
- Rosé and blush wines like White Zinfandel
- Branded wines like Yellow Tail, Mouton Cadet, etc.
- European table wine
- American jug & box wine
- Inexpensive varietals (with the possible exception of Cabernet Sauvignon)
- The majority of Vin de pays
- All Nouveau wines
- Vermouth
- Basic Sherry, Ports
Wines with some aging potential
A guideline provided by Master of Wine Jancis Robinson. Note that vintage, wine region and winemaking style can influence a wine's aging potential so Robinson's suggestion of years are very rough estimates of the most common examples of these wines.
- Botrytized wines (5–25 yrs)
- Chardonnay (2–6 yrs)
- Riesling (2–30 yrs)
- Hungarian Furmint (3–25 yrs)
- Loire Valley Chenin blanc (4–30 yrs)
- Hunter Valley Semillon (6–15 yrs)
- Cabernet Sauvignon (4–20 yrs)
- Merlot (2–10 yrs)
- Nebbiolo (4–20 yrs)
- Pinot noir (2–8 yrs)
- Sangiovese (2–8 yrs)
- Syrah (4–16 yrs)
- Zinfandel (2–6 yrs)
- Classified Bordeaux (8–25 yrs)
- Grand Cru Burgundy (8–25 yrs)
- Aglianico from Taurasi (4–15 yrs)
- Baga from Bairrada (4–8 yrs)
- Hungarian Kadarka (3–7 yrs)
- Bulgarian Melnik (3–7 yrs)
- Croatian Plavac Mali (4–8 yrs)
- Georgian Saperavi (3–10 yrs)
- Madiran Tannat (4–12 yrs)
- Spanish Tempranillo (2–8 yrs)
- Greek Xynomavro (4–10 yrs)
Factors and influences
The ratio of sugars, acids and phenolics to water is a key determination of how well a wine can age. The less water in the grapes prior to harvest, the more likely the resulting wine will have some aging potential. Grape variety, climate, vintage and viticultural practice come into play here. Grape varieties with thicker skins, from a dry growing season where little irrigation was used and yields were kept low will have less water and a higher ratio of sugar, acids and phenolics. The process of making Eisweins, where water is removed from the grape during pressing as frozen ice crystals, has a similar effect of decreasing the amount of water and increasing aging potential.
In winemaking, the duration of maceration or skin contact will influence how much phenolic compounds are leached from skins into the wine. Pigmented tannins, anthocyanins, colloids, tannin-polysaccharides and tannin-proteins not only influence a wine's resulting color but also act as preservatives. During fermentation adjustment to a wine's acid levels can be made with wines with lower pH having more aging potential. Exposure to oak either during fermentation or after during barrel aging will introduce more phenolic compounds to the wines. Prior to bottling, excessive fining or filtering of the wine could strip the wine of some phenolic solids and may lessen a wine's ability to age.
Wines packaged in large format bottles, such as magnums and 3 liter Jeroboams, seem to age more slowly than wines packaged in regular 750 ml bottles or half bottles. This may be because of the greater proportion of oxygen exposed to the wine during the bottle process. The advent of alternative wine closures to cork, such as screw caps and synthetic corks have opened up recent discussions on the aging potential of wines sealed with these alternative closures. Currently there are no conclusive results and the topic is the subject of ongoing research.
Bottle sickness
One of the short-term aging needs of wine is a period where the wine is considered "sick" due to the trauma and volatility of the bottling experience. During bottling some oxygen is exposed to the wine, causing a domino effect of chemical reaction with various components of the wine. The time it takes for the wine to settle down and have the oxygen fully dissolve and integrate with the wine is considered its period of "bottle shock". During this time the wine could taste drastically different than it did prior to bottling or how it will taste after the wine has settled. While many modern bottling lines try to treat the wine as gently as possible and utilize inert gases to minimize the amount of oxygen exposure, all wine goes through some period of bottle shock. The length of this period will vary with each individual wine.
Dumb phase
During the course of aging a wine may slip into a "dumb phase" where its aromas and flavors are very muted. In Bordeaux this phase is called the age ingrat or "difficult age" and is likened to a teenager going through adolescence. The cause or length of time that this "dumb phase" will last is not yet fully understood and seems to vary from bottle to bottle.
Effects on wine
As red wine ages, the harsh tannins of its youth gradually give way to a softer mouthfeel. An inky dark color will eventually fade to a light brick red. These changes occur due to the complex chemical reactions of the phenolic compounds of the wine. In processes that begin during fermentation and continue after bottling, these compounds bind together and aggregate. Eventually these particles reach a certain size where they are too large to stay suspended in the solution and precipitate out. The presence of visible sediment in a bottle will usually indicate a mature wine. The resulting wine, with this loss of tannins and pigment, will have a paler color and taste softer, less astringent. The sediment, while harmless, can have an unpleasant taste and is often separated from the wine by decanting.
During the aging process, the perception of a wine's acidity may change even though the total measurable amount of acidity is more or less constant throughout a wine's life. This is due to the esterification of the acids, combining with alcohols in complex array to form esters. In addition to making a wine taste less acidic, these esters introduce a range of possible aromas. Eventually the wine may age to a point where other components of the wine (such as a tannins and fruit) are less noticeable themselves, which will then bring back a heightened perception of wine acidity. Other chemical processes that occur during aging include the hydrolysis of flavor precursors which detach themselves from glucose molecules and introduce new flavor notes in the older wine and aldehydes become oxidized. The interaction of certain phenolics develop what is known as tertiary aromas which are different from the primary aromas that are derived from the grape and during fermentation.
As a wine starts to mature, its bouquet will become more developed and multi-layered. While a taster may be able to pick out a few fruit notes in a young wine, a more complex wine will have several distinct fruit, floral, earthy, mineral and oak derived notes. The lingering finish of a wine will lengthen. Eventually the wine will reach a point of maturity, when it is said to be at its "peak". This is the point when the wine has the maximum amount of complexity, most pleasing mouthfeel and softening of tannins and has not yet started to decay. When this point will occur is not yet predictable and can vary from bottle to bottle. If a wine is aged for too long, it will start to descend into decrepitude where the fruit tastes hollow and weak while the wine's acidity becomes dominant.
The natural esterification that takes place in wines and other alcoholic beverages during the aging process is an example of acid-catalysed esterification. Over time, the acidity of the acetic acid and tannins in an aging wine will catalytically protonate other organic acids (including acetic acid itself), encouraging ethanol to react as a nucleophile. As a result, ethyl acetate – the ester of ethanol and acetic acid—is the most abundant ester in wines. Other combinations of organic alcohols (such as phenol-containing compounds) and organic acids lead to a variety of different esters in wines, contributing to their different flavours, smells and tastes. Of course, when compared to sulfuric acid conditions, the acid conditions in a wine are mild, so yield is low (often in tenths or hundredths of a percentage point by volume) and take years for ester to accumulate.
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