Wine Words: American Oak vs. French Oak

In a previous Wine Words post I gave a general overview of oak as it pertains to wine.

Today I am going to explain in more detail the difference between American oak and French oak.

To start off, both American oak and French oak are species of white oak. Red oak is never used for winemaking because it is too porous.

While there are many different types of white oak, three are most used for wine cooperage. These are Quercus Alba, Quercus Petraea (also known as sissile oak) and Quercus Robur.

American Oak: Quercus Alba is the type of white oak most grown in the United States. It is grown mainly in the eastern states as well as California. The forests in Minnesota and Wisconsin are considered particularly good sources of oak for the wine industry.

French Oak: Quercus Petraea and Quercus Robur are the two types of white oak grown in France. Of the two Quercus Petraea is considered the finer. The most important oak forests in France are Allier, Nevers and Tronçais (all in central France), Vosges in the northeast, and Limousin, which is more westerly near the Cognac region. Of the five, Limousin is the only forest to grow Quercus Robur.

American and French Oak: The Key Differences: Both American oak and French oak contribute aromas, flavors and tannin to a wine. French oak (particularly Quercus Petraea) is much tighter grained and less dense than the American Quercus Alba. As such French oak imparts more subtle flavors and firmer, but silkier tannins.

American oak being more dense, can be sawn instead of hand-split. This involves less labor and expense. Hence American oak barrels are considerably cheaper than their French counterparts.

American oak is sweeter and contains more vanillin compounds. American oak tends to impart more obvious, stronger and sweeter aromas and flavors. Common descriptors for American oak as well as vanilla are coconut, sweet spices and dill.

Other factors also matter: The provenance of the oak is but one factor that impacts the oak influence on a wine. Other very important factors include:

• The age of the oak — The newer the oak the more oaky aromas and flavors imparted. By the fourth or fifth pass, negligible flavor is left to impart.
• The level of toast (high, medium or light toast) – The higher the toast the more oaky the aromas and flavors.
• The size of the barrel – The smaller the oak barrel the greater the impact of oak aromas and flavors.

Oak – Beyond American or French: I have focused on explaining American and French oak, as these are the two oak sources most used for wine cooperage. However, Slavonian (from northeastern Croatia), Hungarian, Russian and Portuguese oak are still traditional in some wine regions. Similar to France, the type of oak grown in these countries is Quercus Robur and/or Quercus Petraea.