Expertise Level 1
Expertise Level 1
No Comments
No Annotations

  • Add your personal touch to this article. It will appear as part of the content once it has been approved.
    View A Sample
  • Step 1: Log In
    Log in

  • Step 2: Highlight Text
    Select the text you want to enhance

  • Step 3: Add Annotation
    (The button appears after you highlight text)

  • Step 4: Write
    Contribute to the greater good

Oak and Wine

by Staff Writer - B. Shaughnessy | February 08, 2012

The maturation of wine is an essential step in the winemaking process. Wine tasted immediately after fermenting is a beverage that is difficult to drink. Very little of the qualities found in a fine wine are present to the taster immediately after fermentation. It is for this reason that the maturation process is essential. Proper maturation of wine is critical and most quality wines are put through the maturation process by the use of wooden vessels. Wooden vessels are often responsible for adding additional properties to finished wines. Out of the various types of wood available, oak is by far the most popular choice for maturation.

As discussed in wine literature, the natural process of oxidation must be minimized and controlled throughout the entire process of winemaking. This does not mean that oxidation at every step of the winemaking process is bad. On the contrary, oxidation during the maturation process of red wines is essential for wine development. One of the benefits of controlled oxidation is the removal of tough flavonoids. When flavonoids--also known as polyphenols--are oxidized, gravity naturally separates these polyphenols from the wine. The result is a wine that is softer and easier to drink. From a color standpoint, oxygen again plays an important part in red wine production. The action of oxygen allows tannins and anthocyanins to intermingle and produce a stable coloring matter. Wooden vessels used in the maturation process allow for oxygen to work on the wine as described in the processes above. This can be seen in the construction of the stave-type wooden vessel. These stave-type vessels are not airtight and oxygen eventually makes its way to the wine within the vessel.

While the effects of oxidation on the maturing wine are influenced by the use of a wooden vessel, the processes attributed to oxygen do not require the exclusive use of wooden vessels. As discussed in wine literature, processes such as micro-oxygenation are available which trigger the same chemical changes within polyphenols and tannins, but do not require the use of wooden vessels. The use of wooden vessels is far more important due to another set of criteria.

The wine produced immediately after fermentation is far from complete. The maturation process is absolutely necessary in the development of the wine and the use of wooden vessels adds character to the resulting wine. It is with the use of the proper wooden vessel that additional flavors present themselves to the wine. Flavors such as vanilla, roasted almonds, cocoa, coffee, sweet peppers, etc are all attributed to the use of wooden vessels within the maturation processes.

Vintners have an abundance of options available with respect to winemaking processes, and the use of wooden vessels is no exception. Different woods are available as well as different sizes of vessels. In some cases--depending on the wine being produced--it may not be economical to use a wooden vessel in the maturing of the wine. It is logical therefore for the vintner to determine first if the use of a wooden vessel is appropriate and if so, what type of wood to use in the vessel.

Of all woods available, the most popular wood is oak. Oak owes its popularity to the flavor development. Out of the various woods available, oak is the best wood suited for the development of specific flavors that enhance the final wine. Flavors including vanilla and various spices make their way into the final wine due to oak being used. As with the selection of a specific grape variety for the production of a wine, specific oak varieties are available each having different properties. Out of the various oak varieties available, only three are suited for the construction of wine vessels. The three species of oak are Quercus robur, Quercus sessilis and Quercus alba with the latter being an American oak. Out of these three species, the European oak species of Quercus sessilis is generally considered to be the finest oak for the production of wooden vessels.

After the choice of wood has been made, the next decision a vintner must make is the size of the wooden vessel. Different sizes of wooden vessels are available for different applications. It is important to remember that the rate of change observed in the maturation process is inversely proportional to the size of the vessel. Therefore a larger tank will not release as many flavors as a smaller tank. For this reason, large size wooden vats are used primarily for the benefits of oxygen introduction during the maturation stage. Smaller vessels are generally used for the introduction of specific flavors with the 225 liter size--also known as the Bordeaux barrique--being an industry standard.

As with any wood used in any application, oak must be prepared from when it is harvested to when it is made into a vessel. Out of the various woodworking processes, seasoning and toasting are critical steps. Seasoning is the process of the reduction of moisture found within the wood. This is an essential step in any woodworking process. Techniques such as kiln drying can be employed to speed up the seasoning process. The main issue with respect to winemaking is that with the use of a kiln, rough tannins are preserved and eventually make it into the final wine. It is for this reason that natural seasoning is used. The process of naturally seasoning oak takes considerable time with about 3 years being average.

Toasting, simply put is a process used to make the staves of wood more flexible for vessel assembly. However the process of toasting also changes the chemical makeup of the wood in a positive way. The toasting process is controlled by specific heat exposure against the wood surface of the vessel. The more exposed to heat the wood surface becomes, the greater amount of toasting is observed. The bottom line with toasting is the physical change of the wood surface, which leads to the creation of aromatic substances. These aromatic substances are directly responsible for the vanilla, smoky and spicy flavors found within the finished wine.

The use of wooden vessels is not an inexpensive endeavor. Oak is a costly material and if the wine does not require the use of a wooden vessel, the vintner will opt for maturation without the use of wooden vessels. With respect to the price of oak, there are other options available to the vintner when choosing a wood. Also, wooden vessels can be reused. A problem however with reusing wooden vessels is that many of the flavoring components will have been extracted from prior uses. Other techniques exist where wood chips can be manually introduced into the wine. The problem with this approach is that the benefits of oxygen are lost. It is therefore not surprising that the best approach in maturation is the use of new oak vessels.

Add Annotation
Selected Text: Selected Text
What is an annotation? Submit CancelClose

Yea, captchas suck.
Log in and it'll go away.
Add Comment



Copyright © 2012-2014 GrapeHeaven LLC. All rights reserved.