Oxidative aging, reductive aging
As outlined below, wine aging can be carried out in oak barrels, steel vats or other sealed containers (e.g., cement) and of course, also takes place in the bottle. The goal, however, is the same: To provide complexity to the flavors and aromas of the wine.... But what is the driving force behind this development? Who is the main character?... Well, it's none other than Oxygen... by action or omission.
In that case... is it the same on the inside of a bottle as inside a barrel, and what differences exist between the processes of aging and the resulting wine ?
Let’s see:
Oxidative aging (Oxygen)
Oak barrels, regardless of whether they are new or used, are porous containers that allow the continuous and moderate intake of oxygen that gradually integrates into the wine. It is a gradual process that allows oxidation to soften the tannins (in reds), in addition to providing new and delicate flavors (coffee, vanilla, toffee...).
Reductive aging (Oxygen free)
Airtight oxygen free vessels such as steel or cement vats, or the bottle itself, do not add flavor to the wine as such. In fact, the chemical reactions that occur within these types of vessels have nothing to do with those that occur in oak barrels.
When it comes to the aging process in large capacity steel vats, there is none: wine remains unchanged for months. It is purely a matter of size and capacity. In bottle however, chemical reactions inside are produced faster due to a lower volume of liquid present.
As a result, oxygen deprivation will evolve fresh fruit into cooked fruit, and plant and animal notes will appear (leather, mushrooms, farmyard...).
It should be noted that not many wines improve in bottle. Normally the risk is run of losing fruity flavors and animal hints can become extremely unpleasant.
The balance between the presence of fruit and aromas from oxygen free aging is not easy to achieve. It is extremely difficult and incurs high production costs. This is the reason that great wines are sold at higher prices... Of course, when optimal balance is achieved, these wines are the most enjoyable and the most rewarding.