Whiskey Experiments: We Try Buffalo Trace #7 Heavy Char and Hot Box Toasted Barrel Bourbon

Spirit Reviews

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Buffalo Trace has a wonderful tradition of inquiry and experimentation into the form and technique of bourbon making. If you've never heard of their single oak project, I highly recommend reading Michael Dietsch's excellent summary and thought piece on that ambitious enterprise. But Buffalo Trace also has a smaller scale annual release of various experimental bourbons they've been tinkering around with in the warehouse.

At any given time, they have more that 1,500 experimental barrels of whiskey aging, each with unique characteristics, from unusual mash bills, to types of wood, to level of barrel char. Buffalo Trace have taken this dedication to dabbling (they've even constructed an entire micro distillery on-site) so they can leave the major production lines unaltered while pursuing interesting side projects. While experimentation (by its very nature) does not always lead to immediate and amazing results, it's the engine that drives progress and understanding. And while many distilleries conduct their own test runs under wraps, Buffalo Trace has opened their doors and allowed us to peek behind the veil. This year's release features two pretty old bourbons, dubbed the #7 Heavy Char Barrel Bourbon, and the Hot Box Toasted Barrel Bourbon. We gave 'em both a try.

#7 Heavy Char Barrel Bourbon

The experiment here is, you guessed it, the level of char on the barrels. Buffalo Trace usually uses a 55-second char (the famous char #4), but the barrels for this release got a full 3.5 minutes over open flame for the #7 treatment. Filled with Buffalo Trace Rye Bourbon Mash #2 (the same mash used for bourbons like Blanton's and Elmer T. Lee) and aged for 15 years and 9 months.

Bottled at 90 proof, there's no mistaking the fire that went into this whiskey. It smells dark and dusty, a bit like my grandma's attic and old comic books, which is nostalgic for me but not exactly the first thing I look for in a bourbon. The taste has a burnt-tasting bite with a green undertone that reminded us of burning pine cones. It's not super smoky, nor is it at all sweet, though if you really dig you can find black-as-night dark chocolate. It finishes with a lingering bitterness, a bit astringent, and very, very dry. In general, a 15 year old bourbon is hard to pull off, and the char is definitely over-extracted here, but it's a big whiskey and I can recommend with slight reservations to anyone who adores burnt wood.

Hot Box Toasted Barrel Bourbon

With an identical mash bill to the bottle above, Buffalo Trace experimented further with the wood used for this bottling. For the Hot Box, the staves of the barrel were toasted in a 133 degree Fahrenheit "Hot Box" before being steamed, and finally assembled into a barrel. Buffalo Trace says the intention was "to drive the flavors deep into the wood." This bourbon was aged for 16 years and 8 months and bottled at 90 proof—it's almost a year older than the #7 Heavy Char.

The flavor difference between these two bourbons is like night and day. Smelling of sweet caramel and vanilla, the Hot Box is mellow and round on your tongue, with apples and a wonderful mellow sweetness joined by barrel spices. The finish is smooth, warm, and yet mild, and vanishes quickly into the breeze. The only problem with this whiskey is that it's a bit thin bodied and mild, lacking that bit of brashness that makes a bourbon fully a bourbon (to me, at least). You could be forgiven for mistaking this for a Japanese whisky.

In the end, these are both very interesting experiments, if not everyday drinking bourbons. Listing at $47 for a 375mL bottle, they are a fun new perspective on an old art form, and a welcome demonstration of a commitment to the continued pursuit of spirits knowledge. Also, they're super-old bourbons at less than $50 (albeit in a small bottle), so your curiosity doesn't have to break the bank.

Have you tried any of Buffalo Trace's experimental releases? What do you think of the enterprise?

Whiskey samples were provided for review consideration.