Good things cannot be rushed. And so it is with wine.
After the frenzy of harvest, crush, and fermentation, wine usually needs a little time to get itself together. Spending a specified number of months to years aging in an appropriate vessel can do amazing things to improve the profile of a vintage sip.
Sometimes, vintners choose to age wine in a stainless steel tank. Sometimes, it’s a cement egg. Often, especially for fine wines, the choice is a wooden barrel. Whatever the container, the wine undergoes chemical rearrangement during aging, changing the way it looks, smells, and tastes.
As the various components mix and mingle during the aging process, the tannins in the wine form a sort of a molecular conga line. These chain-like molecules of tannins link together and grow long, smoothing out the flavours. Each individual link in the chain holds on tight to its own individual aroma, collecting several on each tannin molecule, forming an increasingly complex collection of sniffs.
Steel vs Cement vs Wood
Most of the tannins in wine, as in red varieties, come from exposure to grape seeds and skins during crush and fermentation. In the process of aging wine before bottling, stainless steel tanks and cement eggs are considered neutral, throwing little into the mix and allowing most or all of the changes during the aging process to come from within the wine.
Wood barrels, often affectionately termed “the winemakers spice cabinet,” bring their own molecules to the party, adding different tannins to the wine as it ages. Depending on what type of wood is used, where it was grown, how it was handled during the cooperage process, and how long it remains in contact with the wine, specific qualities are added to the finished product.
Location is Key
French oak barrels carry a hefty price tag often reaching to $4,000 each for the fine-grained Sessile and Pedunculate oak from regions like Limousin, Nevers, Tronçais, Allier and Vosges. Each region boasts unique qualities in the wood, imparting distinctive aromas and flavours. As a general rule, French oak carries less resin than American oak, lending richer, spicier aromas of vanilla and baking spice from the wood’s inherent chemical compounds.
American White Oak barrels, often used for aging spirits, primarily come from the forests of Missouri, as well as Kentucky, Ohio, Virginia, and Oregon. American oak presents a much looser wood grain than French oak, releasing more tannins for a sharper flavour profile. Barrels made of wood from Hungary and Eastern Europe, while not as fine-grained as French stock, are valued for their addition of rich, bold, and nutty flavours to wine.
Building the Barrels
Construction of the barrels, such as the size, the shape, the curve and thickness of the staves, and ultimately the degree of toasting, from light to deep char, all affect the colour, the aroma, and the flavour of wine stored in them. Again, it’s all about chemical reactions.
If barrel staves are sawn as opposed to hand split, they will emit more tannins and invite enhanced astringency. Air drying the wood, often as long as three or four years, stabilizes the moisture content and dissipates the strong tannins from green wood, producing a much smoother, more complex wine. Kiln-drying the wood bakes in green tannins, affecting the taste and aroma with sharper flavours. French barrels are rarely kiln dried, while some American coopers successfully bake the staves with this quicker, less costly method.
Cooper’s Ingredients, Winemaker’s Recipe
Professional coopers are highly sought-after by the best firms, and well they should be. Their execution must be precise and their materials expertly-prepared. For winemakers, barrels are an incredible tool offering a wide range of wood grains, construction, and toasting, that ultimately finish the aroma, taste, and mouth feel of a wine.
Almost as important as the grapes themselves, selecting a brilliant cooper that makes a high quality barrel with just the right molecular structure and toast level can boost a wine’s appeal by leaps and bounds, adding flavours and aromas like vanilla, coconut, toast, smoke, spices, caramel, butterscotch, and cedar.
Tasting the Difference
A great way to emphasize and define oak’s effect on a sip is to do a horizontal tasting of comparable wines, one oaked, and one naked, or without oak, then judge for yourself. If all you taste is oak, it’s a little overdone. If the wine is balanced, and perfectly aged in the right barrel? Simply divine, but in the end, it truly is a matter of personal taste. Vive la difference!