The

use of oak in wine plays a significant role in winemaking and can

have a profound effect on the resulting wine, impacting the color,

flavor, tannin profile and texture of the wine. Oak can come into

contact with wine in the form of a barrel during the fermentation

or aging periods. It can be introduced to the wine in the form of

free floating oak chips or as wood staves (or sticks) added to wine

in a fermentation vessel like stainless steel. Oak introduced in

the form of a wine barrel can impart other qualities to the wine

through the process of evaporation and low level exposure to oxygen.

Many

winemakers choose to ferment their wine in oak as oak barrels tend

to soften the wine and impart characteristics that improve the flavor

of the wine. The oak wood used for these barrels is mainly derived

from France and the United States although there are many countries

from which oak barrels come including Spain, Hungry, Austria, and

many more. American oak passes on prominent characteristics to the

wine, while French oak tends to lend more subdued characteristics.

Each type of oak imparts notes of vanilla, caramel, cream,

clove, smoke, and fresh cracked black pepper. Another important

trait passed over from the oak is the tannin found in the wood –

tannins from American oak are sharp while French oak provides more

subtle tannins.

Some other differences

to note are that American oak tends to be more intensely flavored

then French oak with more sweet and vanilla overtones due to the

American oak having two to four times as many lactones. Winemakers

that prefer American oak typically use them for bold, powerful reds

or warm climate Chardonnays. Besides being derived from different

species, a major difference between American and French comes from

the preparation of the oak. The tighter grain and less watertight

nature of French oak encourages coopers to split the wood along

the grain rather than saw. French oak is then traditionally aged

or "seasoned" for at least two years whereas American

coopers will often use a kiln-dry method to season the wood. Long

periods of outdoor season has a mellowing effect on the oak that

kiln-dry methods have difficulties replicating. The sawing, rather

than splitting, of American oak also enhances the differences between

the two styles due to the rupture of the xylem cells in the wood

which releases many of the vanillin aromatics and lactones responsible

for characteristics like the coconut notes.

The length of

time that a wine spends in the barrel is dependent on the varietal

and style of wine that the winemaker wishes to make. The majority

of oak flavoring is imparted in the first few months that the wine

is in contact with oak but a longer term exposure can effect the

wine through the light aeration that the barrel allows which helps

to precipitate the phenolic compounds and quickens the aging process

of the wine. New World Pinot noir may spend less then a year in

oak. Premium Cabernet Sauvignon maybe spend two years. The very

tannic Nebbiolo grape may spend four or more years in oak. High

end Rioja producers will sometimes age their wines up to ten years

in American oak to get a desired earthy, vanilla character.

These may not

seem like important factors at first, but as you explore the world

of wine you’ll begin to notice subtle differences. California

Chardonnays are often aged in toasted oak for a long period of time,

which imparts the intense vanilla flavor that many have grown to

love. But the fruit flavor drops off almost as soon as the wine

is swallowed, a problem which many call "overoaking"

a wine. Meanwhile, Chardonnay wines from Chablis in Burgundy have

subtle vanilla flavors from shorter barrel storage, which allows

the wine a crisp finish with fruit flavors that linger in the back

of the throat long after being swallowed.

White

wines that are fermented in oak often have a pale color with an

extra silky texture. White wines that are fermented in steel and

then matured in oak will have a darker coloring due to the heavy

phenolic compounds that are still present. Flavor notes that are

common descriptions of wines exposed to oak include caramel,

cream, smoke, spice and vanilla. Chardonnay is a variety

that has very distinct flavor profiles when fermented in oak that

include coconut, cinnamon and cloves notes. The

"toastiness" of the barrel can bring out varying degrees

of mocha and toffee notes in red wine.

While oak aging

is time honored and respected some wine lovers prefer wines that

are fermented in steel barrels. These wines often have a more fruit-forward

flavor and can be more true to the actual grape flavor. In these

wines, we may feel slighted by the minimized tannins and lack of

barrel spices, but these wines exude a more true expression of the

grape. Oak aging can be seen as a more old world practice while

steel aging will tend to be seen more in the new world as in New

Zealand and Australia. One is not necessarily better than other.

It is all a matter of preference. If you prefer a little more complexity

and like more tannic wines go for an old world wine that is oak

aged. If you like a more fruit forward wine then stick to a steel

aged wine from South America or New Zealand.