Definition - What does New Oak mean?
New oak refers to newly made barrels and the first time they are made for aging wine. As the barrels are fresh and have never been used, the phenolic compounds and flavonoids are at their strongest. Wood tannin is also fresh, so tannin which will be imparted into the wine will be firm.
WineFrog explains New Oak
New oak is often used to age wines which already have bold and firm structure on their own. These are the types of wines which can hold up to the added structure, aroma and flavor profiles that new oak barrels will impart.
Aromas and flavors associated with new oak are smoke, cedar, toast, wood shavings, coconut, vanilla, etc. While used barrels can impart hints of these elements, new oak will have a much stronger and more concentrated effect on the wine.
On average barrels can be used up to four times and still impart certain aromatics and structural components to wine. More delicate wines are aged in second- and third-use barrels.