Is that a 2X4 that I smell in my wine glass? Wine tasting notes often refer to wines as oaky, but what exactly does that mean? The use of oak in winemaking can play an important role in the final product in several different ways.
First, consider the source of the wood. Most American oak barrels typically come from the species Quercus alba, which is a white oak species. This oak has wider grains and lower wood tannins. The wider grains allows for a quicker, more concentrated release of aromas into the wine. American oak typically imparts flavors with sweeter nuances like vanilla, along with coconut (think sunscreen) and dill (think pickles). This oak is used for big, powerful reds and Chardonnays from warmer climates.
In France, Quercus petrea is more common for its finer grain and richer aromatic components. This produces silky, softer style tannins. Warm sensations such as baking spices (cinnamon, clove, nutmeg) are more apparent with this type of wood. Some winemakers choose their wood from one specific forest as each forest may add slightly different nuances to the final blend. Due to the finer grain of French oak, less of the tree may be used in barrel production. Therefore, the cost of French barrels is more than that of American barrels.
Another varying degree is the amount of 'toast' inside the barrel. Yes, it's the same concept as when you 'toast' a piece of bread (not the toast at your friend's wedding...). Toasting ranges from lightly charred, medium toast, to heavily toasted. The lighter the toasting, more of the original oak flavor is imparted on the wine. The heavier the toast, you see a reduction in the coconut notes and the color of the wine as it reacts to the toastiness of the barrel.
The size of a barrel is important in regards to the ratio of surface area to volume. The most common size is the Bordeaux barrique which hold 59 gallons (225 liters). The next most common is the Burgundy barrique at 60 gallons (228 liters). Some winemakers use a foudre, a large barrel made of oak (or chestnut) that ranges in size from 150-350 hectoliters. These large vessels are used more for ageing the wine than for the qualities the wood imparts on the wine.
This takes us to the age of a barrel and it's varying effects. The first time a barrel is used, it provides a wine with good texture and a substantial amount of tannins. With each subsequent years the barrel is in use, the nuances it offers become less. Some wineries use only 100% new oak every year (now you know why that wine costs so much!). Others will use the barrel up to three years, then scrap the inside of the barrel, retoast it to their specifications, then put it back into rotation. 'Seasoned' barrels (used several years without a retoasting) are referred to as neutral barrels and impart very little on the wine, but allow it to age with a slight exposure to oxygen.
Next time you open a wine from your STORE collection, think about all these barrel factors and how they help to create the tastes and aromas of your fine wine.