Will this wine age?

What actually preserves wine

Four things, in roughly this order. Everything else people cite either correlates with longevity or is folklore.

1. Acidity. A low-pH wine is chemically and microbiologically more stable, and it is the single best predictor of longevity across every style. It is why Riesling outlives most reds, and why Hunter Sémillon — light, unoaked, bone dry, with no tannin and no sugar to help it — can be extraordinary at twenty years.
2. Tannin and phenolics. Antioxidants, consumed by oxygen ahead of everything else. They also polymerise into longer chains that taste softer, which is the change people mean when they say a wine has “come round”.
3. Sugar. A preservative at the concentrations found in botrytised and fortified wine. Sauternes and Tokaji last for decades partly on this.
4. Alcohol. A preservative above about 15%, which is essentially the point of fortification — with one large exception noted below.

Body, oak and sheer concentration all correlate with longevity and none of them causes it. A big wine has more to lose and therefore takes longer to lose it, which is not the same claim as “big wines age”.

The exception worth knowing

Fortified wine ages — except under flor. Fino and Manzanilla spend their lives beneath a living yeast film that consumes the oxygen and much else besides. Once bottled the wine has neither that protection nor the oxidative toughening its Oloroso siblings received, and it fades within months. It is the one fortified wine that should be bought fresh, and the reason the bottling date matters more than anything else on the label.

Amontillado begins under flor and finishes under air, which is why it behaves like the long-lived Sherries rather than the short-lived one. Nothing in a taste profile records this, so WineHQ records it explicitly rather than inferring it.

The five bands

What changes if you keep it

Colour

Reds move from purple towards ruby, then garnet, then brick, and lose depth at the rim. Whites move the other way — from pale straw towards gold and eventually amber. Both are gradual and both are visible against a white surface.

Tannin — reds

Tannin molecules polymerise into longer chains, which are perceived as softer, and eventually become large enough to fall out of solution as sediment. This is the change people mean when they say a wine has "come round".

Fruit

Fresh primary fruit fades and shifts register — from blackcurrant towards dried fruit and prune, from green apple towards baked apple and honey. What is gained is not more fruit but different fruit.

Tertiary aromas

Leather, tobacco, forest floor, mushroom, truffle and dried herbs in reds; honey, nuts, toast, beeswax and petrol in whites. These are not present in young wine and are the reason anyone bothers.

Acidity

Total acidity barely changes, but it becomes more prominent as the fruit that was balancing it recedes. An old wine tasting sharp is usually a wine whose fruit has gone rather than one that gained acid.

Sediment — reds

Polymerised tannins and colour compounds precipitate. Entirely harmless, gritty and bitter in the glass, and the reason mature reds are decanted.

Every style, by band

Derived from each style’s own taste profile, with the reasoning shown on the style’s page. Where the same style covers wines built for next week and wines built for decades, it is listed as “genuinely depends” rather than averaged into a band that describes neither.

Things that shorten it

• Warm storage. The factor that most reliably shortens a wine’s life, and the one you can do something about. See storing wine.
• Temperature swings. Repeated expansion and contraction works wine past a cork. A steady 17°C beats a cellar that ranges from 8°C to 22°C.
• The closure. Synthetic corks let through more oxygen than any alternative and are not intended for long keeping. See closures.
• Light. Light strike is a documented reaction, and clear and pale bottles are the vulnerable ones.

Two honest caveats

Age is not improvement. A great many wines are made to be drunk within two years and get worse rather than better with time, and there is nothing second-rate about a style that is at its best young. Most of the wine sold in the world is in this category, including a good deal of expensive wine.

Bottle variation at twenty years is large. Especially under natural cork, where oxygen ingress differs measurably between individual closures from the same batch. Two bottles of the same wine from the same case can be at noticeably different stages, and no model — this one included — can predict which one you are opening.