Bottles of the Single Oak Project, a new bourbon line from Buffalo Trace Distillery. (Couresty of Buffalo Trace Distillery)

Magical things happen inside that barrel in terms of flavor, texture and aroma. Beyond what sort of wood is used, the location of where the barrel sits in the warehouse matters greatly — a barrel sitting at ground level ages differently than one resting on a higher floor. In this way, the warehouse becomes a man-made terroir — similar to a winery, in which grapes from different geographic locations will take on different characteristics.

I’ve previously discussed the importance of aging and blending in the process of making whiskey. The craft of distillation is certainly of utmost importance — if mediocre whiskey comes off the still, it’s not going to get better after 10 years in a barrel. But how whiskey ages in a barrel is just as critical.

In this week’s column, I discuss Buffalo Trace’s new Single Oak Project, which is part of the distillery’s larger two-decade search for the Holy Grail of bourbon. Buffalo Trace went into the Missouri Ozarks to hand-select 96 trees. Those trees were split in half, then made into staves for 192 barrels, each tweaked according to numerous variables.

For instance: Half of the barrels were air-dried for six months and half for 12 months. Some of the barrels were charred dark, and some were charred lighter. Some barrels were filled with wheat-recipe bourbon, others with rye-recipe bourbon; some of the contents was 105-proof, some 125-proof. Eight years later, those whiskeys have come out the barrel and have been bottled separately. We can now see what each variable has produced. It was clearly worth the wait.

But that’s thing about about whiskey: the waiting. It takes many, many years to see just how that hunch, that tweak, that bright idea, that “eureka” moment — the one that may or may not take you one step closer to the perfect whiskey — will turn out. Most of the master bourbon distillers in Kentucky are not young men, and that is no coincidence.

Harlen Wheatley, who is Buffalo Trace’s master distiller is only 42, but he’s already been working there since he was in his 20s. Wheatley is only the sixth master distiller at Buffalo Trace since the Civil War; the guy he replaced dated back to Prohibition. Making great whiskey demands a lifetime of knowledge. As the distillers age — along with the barrels — they know that they may never taste the fine whiskey they are creating.

This happened with the bourbons I wrote about this week. The man who went into the Ozarks to choose the white oaks for the Single Oak Project was named Ronnie Eddins, Buffalo Trace’s long-time warehouse manager. If you go to the Single Oak Project Web site, you actually can see videos of Eddins chatting with the loggers of those trees. Throughout the aging process, he was instrumental in creating these bourbons. Sadly, Eddins died earlier this year. He did not live to see the Single Oak Project bottled and sent to market.

I find this incredibly poignant: The idea that a younger generation sips what a previous one struggled to make. It perhaps gives spirits a sort of transcendency. In any case, it certainly suggests that a fine whiskey is beyond the realm of simply being hooch to get drunk on.

Wilson is the author of “Boozehound: On the Trail of the Rare, the Obscure, and the Overrated in Spirits” (Ten Speed Press, 2010). He can be reached at Follow him on Twitter.