One of many wine-related befuddlements is trying to understand what the big deal is about oak. If you listen to some wine folks at (usually higher-end) tastings, as part of the oenological word salad that they're coming out with -- they make reference to oak, the amount of time spent in oak, oaky flavors, American oak, French oak, poison oak (well, maybe not), and occasionally "unoaked." I have a basic knowledge -- oak gives certain character to wines and the longer a wine spends in oak while in the aging stage after fermentation, the more pronounced those flavors flavor usually are. However, the subtle variations leave me rather lost in the forest for the trees.
[Please note: The Naked Vine takes no responsibility for any injury stemming from physical reactions to the bad metaphor in the last line. It just needed to be said.]
Let's start with the basics. Why age wine in barrels in the first place? They're potentially leaky, allow wine to evaporate, and grow and shrink with changes in temperature and humidity. We can make larger, cheaper containers out of steel or glass or polyurethane these days. Why do we insist on keeping this old tradition alive?
The main reason? It works. The barrel can be as much a part of a wine as the method of fermentation, the terroir, or the grape itself in some cases. When a wine is barrel aged, a number of things happen. First, wood is water-soluble. Even though the inside of a barrel is "toasted" to cure the wood, wine will invariably seep into the wood. The newly fermented wine absorbs various chemical compounds from the wood itself.
Also, barrel aging allows a slow oxidation of wine. Oxidation is why we swirl wine -- helping bring out certain flavors. Alcohol evaporates when exposed to oxygen, so some of the vapors find their way out through cracks in the wood. As the alcohol evaporates, the level of wine in the barrel drops. (In whiskey parlance, the evaporated alcohol is called "the angel's share.") Winemakers "top up" barrels with additional wine during the time in barrel.
Both of these actions add certain flavors and augment existing flavors in a wine. Tannins tend to get softened a bit in red wines, and both reds and whites gain complexity through the process.
The type of wood used in the making of the barrels plays a major role. ("Cooperage," in case you were wondering, is the making of barrels.) American oak, being a less dense wood than French oak, allows more seepage, thus imparting more characteristics from the barrel. New barrels impart more flavors than old barrels. Some varietals pick up more character from wood than others. The longer the wine stays in contact with the wood, the more flavor it picks up.
Some wines are aged entirely in one type of barrel. These are the ones you hear referred to as "100% American oak" and the like. Some batches of wine are aged piecemeal in several types of oak. Some are aged partly in oak and partly in stainless steel, cement or some other storage medium. (Some winemakers also cheat. Rather than truly barrel-aging, they age wines in steel tanks and add toasted oak chips to impart these character. This is a more cost-effective method, but it doesn't work as well...) All of these factors go into the winemaking process. A winemaker will determine what kind of wood, length of time, etc. will add the desired characteristics.
I asked some of my pals in the "biz" for their thoughts about the various types of oak. Their thoughts:
Danny Gold from The Party Source: "American oak can smother wines and make wines such as Chardonnay taste like 4x4's where a Chardonnay aged in French will be more floral with vanilla undertones. [I think] American oak will give a wine a woody backbone while French oak will give it romance."
Kevin Keith from D.E.P's Fine Wines: "I have often thought of it as a difference between deer meat from this area as opposed to Pacific Northwest or Cali. Around here, deer are corn fed so their meat is sweeter. I know that is weird. You could also think of it as American oak imparting a cocoa/vanilla spice as opposed to French lending more nutmeg and cinnamon."
What does this mean in real terms? Chardonnay (as Danny mentions above) may be the easiest way to examine the distinction. Chardonnay is the oenological version of vodka. It's the blank canvas that really takes on the character of where it's grown and how it's made. When it comes to oaky chardonnays, California's versions immediately pop to mind.
I did a little research and found four California chardonnays -- two aged in American oak and two in French -- all in the $10-15 range, so you could easily try this at home. I tried Kendall Jackson 2008 Vintner's Reserve Chardonnay, Bogle 2008 Chardonnay, Francis Coppola 2008 Gold Label Chardonnay, and Heron 2007 Chardonnay. The Bogle is 100% aged in American oak. The K-J is a mix of American and French. The Heron and Coppola were a 50/50 blend of French oak and stainless steel.
Now, this obviously isn't a truly scientific experiment. My pal Jim Voltz from Bond Street Imports suggested getting some varietally consistent wines from the same winemaker aged in various ways (and they carry a couple done just that way), but I didn't want to get too far afield...
What did we find? I expected the 50/50 mixes to be less oaky, but I was completely incorrect. Both the Coppola and the Heron were much more "toasty" than the ones aged in American oak. In fact, the Coppola was like drinking a charcoal briquette at first. Like really tannic reds, I think oaky chardonnays need some time in air to let the flavors come out -- otherwise, the oak tends to overwhelm. I thought Danny's observation was spot-on. The greater the percentage of French oak, the stronger the vanilla flavors. Even though American oak tends to impart more flavor, both the K-J and the Bogle were easier to drink overall. The "toasty" taste seemed fuller in the wines made with the French oak. It felt more broadly on my tongue.
The Heron was my favorite of the four, as I thought it had a little more complexity and the oak that was there wasn't as strong. The Heron also didn't do malolactic fermentation, which removed the "buttery" aspect -- so it had a more fruity taste.
The Sweet Partner in Crime had a hard time participating in this little exercise. She cut her white wine teeth on California chardonnays, but now she finds them "too much" for white wines. I also prefer wines that are more crisp than creamy, but I didn't mind these as much as she did.
What's the bottom line? Using oak can allow a winemaker to express his or her vision and wineries produce wines that they think people will enjoy. I just don't have enough experience looking at wines from a "wood" perspective. One observation I can make: French oak barrels are much more expensive than their American counterparts, so if a wine's notes include the use of French oak -- especially in a white wine -- you should be ready for that wine to "show off" the fact that it's been so oaked.
Just for fun, if you're presented with "this wine was aged in French oak," you come back with, "Yes, you can really get the vanilla notes, but the barrel may have been overtoasted," just to see the reaction.