Definition - What does Oak mean?
Oak is a hardwood used to construct barrels, chips and powders in the wine industry in order to either store wine during fermentation or to age wine. Instead of aging or fermenting wine in any other material, oak is highly sought after because of its great contribution towards improved aroma, shade, taste, texture and tannin profile of the wine.
Both white and red wine can be aged in oak barrels, which develops the wine's future characteristics. Oaked white wine is almost the hue of straw with a significant vanilla flavor while oaked red wine is darker in shade and can develop flavors of toffee, caramel, honey or mocha. Though these changes are the most noticeable, other changes being in the texture and the tannin profile, contribute towards the quality of the wine.
The three main types of oak used for these purposes are American oak, French oak and Eastern European oak.
WineFrog explains Oak
Storing wine in oak barrels so that it can be considered “oaked” has two other alternatives. Instead of using oak barrels to oak wine, vintners have now started using oak powders and oak chips for the same purpose. This means that a wine can be oaked by either storing it in oak barrels for a certain period of time, or by storing it in stainless steel tanks and letting them be in contact with oak powders and oak chips.
The best time to use oak powders is when the wine is fermenting. This is because the wine is fermented for a specific time, which means the wine will be in contact with the oak powders only for a specific time, reducing chances of over-oaking the wine.
The best time to use oak chips is after the wine has been racked for bulk aging. These chips are said to give the wine the best possible oak flavor during the first week of aging. Depending on the type of wine stored, the time needed for the wine to age is set accordingly. On average, white wine is not as commonly stored in oak barrels for the purpose of aging; red wine benefits most from this process, but some white wines can as well. White wines are often meant to be served as crisp wines, which require much less contact with oak properties.