Why You Should Care About Oak

If you read technical specifications about wine or listen to people who speak, often loudly, about wine, you might notice that the oak in which the wine was aged is being trumpeted. In fact, you likely hear terms such as new (never used previously); once-used, previously used, or used; or neutral (used twice or more previously at which point it is more of a storage vessel for fermentation than anything else).

Should you care? Why?

The short answer is yes. The reasons are extremely technical, but we can take those technical reasons and largely ignore them to explain the wine reasons behind it.

Likely more than any other type, we hear about a wine having been aged in French oak. In France, one cannot imagine, and it might even be against the law, but I don't know that, that a French wine would be aged in other than French oak if it is aged in any oak. And, while not all French oak is the same, oak that is referred to as French oak is technically quercus robur (yes, I knew that without the benefit of Google, but don't ask me why it stuck in my head because I can't answer that).

French oak, of all the oak used for wine barrels has the tightest grain or striations. And, old oak tends to have far tighter grains than younger oak. Other European oak, particularly eastern European (Hungarian, Slovenian, Slovakian, Russian) tends to have what we might describe as medium grains while American oak (quercus alba) typically has very wide striations. 

The tighter the striations, the more that is typically absorbed from the oak into the wine. And, for some reason that people more knowledgeable than me know, Chardonnay and Pinot Noir absorb from oak more readily than most other grapes. Cabernet Sauvignon, on the other hand, absorbs more slowly.

Now, recall that, particularly in red wines, oak imparts tannins into wine and tannins are one indicator of wines having a higher degree of ageworthiness.As a result, by combining the thoughts from the last several paragraphs, all other things being equal, we find that wines aged in French oak tend to be the longest lived while those aged in American oak derive less ageworthiness from the oak. To take it to another level, those wines aged in a vat full of oak chips get very little of value other than oakiness from that oak.

So, let's consider what each type of oak brings to a wine and which grapes it is likely to be compatible with. Where it comes from seems to be both from the tightness of the grain and the natural habitat in which it normally grows.

Flavors from French oak are more subtle than from most other wines. But, more so than other oak, it tends to impart structure and balance as well as spice, particularly baking spice to a wine. In particular, as we noted above, Chardonnay and Pinot Noir love French oak. At the same time, French oak is the most expensive oak for making barrels, so there is a tradeoff.

Hungarian oak, in particular, imparts a lot of nutty flavors to a wine. It's less expensive than French oak, often by a wide margin, but it needs hearty wines to not be overwhelmed by the notes imparted by the oak. Malbec, Petit Verdot, some of the white grapes indigenous to the areas, and sometimes Nebbiolo, and of course, Kekfrancos/Blaufrankisch.

American oak tends to be the least expensive for barrels of the major areas from which oak barrels for wine are made. The key flavors imparted to the wine are vanilla, coconut, vanilla, dill, and ... did I say coconut. And, while it is the least expensive of the three, some major higher-end producers reportedly use exclusively American oak, most notably perhaps being Silver Oak. So, if you like baking spices in your Cabernet, stay away, but if you like the softness of vanilla, that's a place to look.

So, as you can see, oak does make a difference. There is far more to it than this, but it does tell you it might be worth considering.