Wine Arcana

Concept

Bottle aging

Also known as Bottle ageing

Bottle aging is the development of wine after bottling, as its aroma compounds, pigments, and other constituents continue to react. Some wines gain aromas and textures that drinkers value as mature character. Others are most appealing while their youthful fruit remains vivid. The useful aging period depends on the wine's starting composition, its packaging and storage, and the drinker's preference for fresh or developed flavours.

Changes in the wine

Aroma evolves as existing compounds break down and new ones form. Compounds inherited from grapes can also release aroma during storage. In Riesling, for example, the compound TDN contributes a petrol-like note that can become more conspicuous with bottle age. Its impact depends on concentration and the surrounding aroma.

In red wines, pigments called anthocyanins react with tannins and other compounds to form new pigments. The colour can lose its youthful purple cast and develop a more orange hue. Tannin concentration and structure also change, contributing to the softer texture of many mature reds. Several reactions occur together, and the size of tannin molecules can increase or decrease. A two-year Australian Wine Research Institute trial found declining tannin concentration and size alongside an increasing proportion of pigmented tannins.1. Jacqui McRae & Paul Smith, “How wine pH and closure selection influence red wine colour and tannin during ageing,” AWRI Technical Review 207 (December 2013), pp. 14–18. The trial followed one Cabernet Sauvignon under different pH and screwcap-liner treatments for 24 months.

Oxygen and the closure

Wine carries some dissolved oxygen into the bottle, and more may remain in the headspace above the liquid. The closure affects subsequent oxygen entry. Oxidation consumes protective sulfur dioxide and changes aroma and colour; the response depends on the wine's phenolics and other reactive compounds. Limited oxygen exposure can preserve fruit, while some wines develop sulfurous aromas under low-oxygen conditions. Closure selection therefore works with the composition established in the cellar.

Storage and pace

Cool storage slows chemical change. In an AWRI trial, bottles of one Cabernet Sauvignon held for a year at about 21.5°C lost more sulfur dioxide and showed more advanced pigment changes than bottles kept at about 15.1°C. Both groups remained sound at the end of the trial.2. Eric Wilkes, Bryan Newell & Dan Johnson, “Wine storage temperature – investigating the impact of small differences,” Wine & Viticulture Journal 34(3) (2019), pp. 27–29. The authors caution against extrapolating the size of the effect to other wines or short periods of heat exposure. The result shows how an ordinary room temperature can alter development over time, even without extreme heat.

For prolonged storage, a cool, dark place with a stable temperature limits heat damage and light-driven reactions. The wine's history in transport and storage helps explain why bottles of the same vintage can develop differently. Following several bottles over time reveals how a particular wine develops.

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