There’s no doubt in my mind that wine fermented in oak barrels has a very different and distinct flavor than wine fermented in stainless steel. The phenolic material from an oak barrel ultimately imparts a variety of flavors depending on the growing region of the trees, tightness or width of the wood grain and toasting levels (light, medium or strong) of the barrels. The flavors that the wine barrels impart into the wine are technically called organoleptic characteristics.
The French oak used in making barrels comes from three particular growing regions in northern, eastern and central France. In general, French oak possesses organoleptic characteristics of butter, smoke and clove. Each region imparts additional, unique flavors in the wine. For example, oak from the north-central region possesses flavors of spice, while the south-central regions impart vanilla. Eastern France produces oak barrels that taste greenish or like spicy pears or apples. Milky, cinnamon spices are found in oak from the central regions of France. American Oak imparts organoleptic flavors of dill, cucumber, coconut, baking spices and vanilla.