Oak | How does it affect wine?
Oak can be one of those tantilizing subjects. It's so widely used in different wines around the world that it's easy to understand why you would wonder what is oak, how it's used to influence the wine and how if affects the wine.
So what is oak?
When we talk about oak we're referencing Barrels. Barrels have been used throughout history as a way of storing wine and transporting it over long distances. Nowadays, barrels are primarily used to influence the taste of a wine. There are two types of barrels, Neutral oak which doesn't impart any flavour into the wine and new oak which does impart flavour. Winemakers usually prefer new oak for their barrels as it allows the wine to take on new flavours, making the wine more complex.
Two different types of oak are used in order to make these barrels. Franch oak is made from select forests in northern France (Tronçais, Nevers and Vosges). American oak on the other hand doesn't come from select forests but from over 18 differents states, nevertheless the best oak also comes from northern states where the climate is cool and dry, perfect for getting the best wood grain needed to make these barrels.
As these oaks are different species they give off different flavours in the wine. French oak is subtle and spicy with hints of vanilla, clove, cinammon and baking spices whereas American oak is much stronger in flavour with high extracts of vanilla, dill and coconut.
So how are barrels made?
Barrels like the best wines are made in an artisanal fashion. The process starts with the wood. As mentioned previously, tonneliers or coopers prefer using wood from cold climates as the grain is smaller which allows for a more gradual penetration of flavours in to the wine. This means that the oak will be better integrated and more mellow on the wine. 150 to 200 year old oak trees are cut down in order to form the staves that will make up the barrels. These staves are then left outside to dry in contact with the elements. This "seasoning" process can last a few years over which the contact with the outside elements will be able to extract the harshest tannins from the wood.
Once this process is completed the wood is brought inside and reshaped in order to have seemless joints, necessary in order to avoid leaks. The wooden staves are then assembled over an open fire and held together using iron hoops. The open fire allows to bend the staves into a curved shape needed to make the barrel. Once the barrel is correctly shaped it is place once again on an open fire so that the flames can toast the inside of the barrel. This toasting is what will allow the wine to acquire those toasted notes that often accompany an oaked wine. Winemakers can choose whether to have their oak lightly, medium or strongly toasted and the choice will largely depend on which wine or wines he plans on using oak.
Finally oak can be used in two instances. One to ferment the wine or two to age the wine. The most common practice is to age the wine in oak as it's only by using this method that you will get the strongest flavours in the wine.
So how does the oak influence the taste of a wine?
Like seasoning, oak must be used to enhance the natural flavours found in the wine. Nevertheless, sometimes oak is used to hide mistakes that were made during the winemaking process. Consequently it's the winemaker's job to try to find the right balance with oak in order for the new flavours to enhance the natural fruity flavours in the wine while at the same time not masking them.
In recent years the new trends have been to have unoaked wines, surely due to a massive inability to control the oak's impact on the wine. Like too much salt on a dish, oak must be used sparingly in order to extract the best flavours and inhance those that are already present in the wine.
So what are your thoughts? Do you prefer oaked or unoaked wines? Which are your favourite oaked wines?