Distillers char the inside of their barrels at varying levels, ranging from Level 1 (15 seconds) to Level 7 (3.5 minutes) and beyond. We char at Level 3 (40 seconds), which leaves a ¼-inch-deep layer of char inside the barrel. This process caramelizes the oak’s sugars and creates a dense layer of smoky sweetness waiting to be dissolved.

By breaking open the wood’s cell walls through charring, the spirit gains access to flavor compounds such as caramelized wood sugars, vanillin, and spice.

Lighter char levels tend to produce more fruit esters and spice notes, while heavier char levels release desirable oak flavors into the spirit more quickly.

Charred wood filters the spirit by trapping undesirable aromas within it, and creates chemical components that turn clear distillate brown as it matures.

Good Bourbon comes to those who wait. As temperature fluctuations cause the oak to expand and contract, the liquid seeps beyond the char and caramel layers to interact further with the oak, extracting deep notes of spice and wood. Liquid evaporates, oxygen enters, and chemical reactions create even more flavors and aromas. On average we lose 6% the first year because of soakage then 3% every year after that.

Water dissolves wood sugars that contain the sweeter vanilla and caramel notes. Alcohol extracts tannins that give the spirit complexity, depth, and a drying sensation on the palate.

Liquid evaporation allows oxygen to enter, causing many chemical reactions, like esterification. Esters are chemical compounds within whiskey that produce fruity aromas and sweet flavors.

Sometimes a whiskey’s flavor is less than desirable due to too many years in the barrel, or because of excessive evaporation (a.k.a. the “angels’ share”) under prolonged heat exposure.