How does whiskey develop its unique flavor profile?

How do whiskey, rye, and bourbon develop their unique flavor profile?
September 13, 2013

How does it get its nice mellow flavor and just what’s going on in the 53 gallon oak barrel aging for decades?
Here to talk about that is Thomas Collins.
He’s the director of research for the food safety and measurement facility, University California, Davis.

I studied oak aroma and flavor chemistry for the wine industry.
At the time, I worked for a large winery in California that owned a cooperage and we did a lot of work looking at oak chemistry and how it impacts the flavor of wines.

the toasting process and whether this is toasting for wine or toasting for whiskey or charring for whiskey … toasting is the process once the barrel has been formed into shape, of heating it over a fire to basically heat it enough to break down some of the structural components of the wood itself.
And so you get some flavor compounds that are released from the breakdown of lignin or cellulose or some of the other structural components of the wood.

And then, when you put wine, or in this case whiskey, into that barrel, ethanol is a very good solvent and it will extract some of those components from the wood itself and that becomes part of the composition of the wine or the whiskey.