Knowing a particular region’s vintage conditions can unlock the secret of what a wine might taste like — including in the future. This is called the aging potential. What is aging potential, though, and why would you want to drink old wine?

An estimated 90 percent of wine produced in the world is meant to be drunk within two years of its vintage. While they should be delicious, young wines are often simple, and they are focused on primary and secondary flavors.

Primary flavors are those that come from the grape itself. They are usually fruit-focused, like berries in red wine and citrus or tropical notes in white. Floral character and minerality can also shine through from the grape, like in Riesling or Pinot Noir.

Secondary notes are those imparted by the winemaking. Cultured yeasts, say, can produce wines with prescribed flavors like orange or pineapple notes. Cold fermentation of whites can make pear-drop or banana flavors. Carbonic maceration of reds leads to a bubblegum character. New French oak adds vanilla and baking spices to both red and white wines.

All of these primary and secondary notes are in the wine when it is bottled. Within a few years they start to break down and the wine is no longer drinkable. They can taste stale, or flat, turn to vinegar, or oxidize into a soy saucy, mushroomy mess.

If a wine possesses a certain high level of structure, though, it has the potential to improve. This happens through chemical reactions and oxidation of the compounds in the bottle, and it transforms primary and secondary into tertiary flavors. The wine becomes something different and greater than the sum of its parts. 

When we refer to structure, we mean the physical constituents of a wine, as in the acid, alcohol, concentration of flavor compounds, tannins (in reds), and sugar (in some whites). They can also be imparted through winemaking, like the influence of oak flavors and tannins or extended contact with grape skins or lees (the dead yeast cells after fermentation). These particulates literally build a wine, and give it shape on your palate.

Each grape variety has a particular structural range that makes it unique. Cabernet Sauvignon has high tannins and acid with moderate to high flavor concentration; Chardonnay has moderately high acidity and is particularly susceptible to the influence of oak and lees. 

The structure of an individual wine is dictated by a combination of the vintage and the farming. When a region’s vintage is rated favorably by critics, it is because the structural components are high and in balance, offering the chance for wines made from them to have a high aging potential.

Tertiary flavors come in a huge range, including earth, leather, wood, spices, rocks, tobacco, dried fruit, nuts, tar, florals, etc. Part of their desirability is they tend to be unattainable, in their myriad combination, through any process other than the slow aging of wine.

Scientists and winemakers have been trying for decades to speed up the process or mimic the flavors of aged wine in a lab. Although there is a greater understanding of how the changes happen, and impart a sense of control over specific circumstances required to achieve them, no one can seem to recreate the inimitable experience of perfectly cellared wine.

This is the why. Until you’ve had a wine that was aged properly, it’s difficult to describe the unexpected, singular experience of drinking one. They are not for everyone, and can elicit off-sounding tasting notes like swamp water, smoke, an old basement, or chlorine. 

Why would anyone want to drink a beverage that came from a fruit that tastes like an old cupboard? All I can say is, trust me: A perfectly aged wine is nothing short of a masterpiece.