Bourbon and Tennessee Whiskey are not the same thing. Sure these two whiskeys historically hail from states that are right next to one another and they both look eerily similar side by side in a glass, but to call a Tennessee Whiskey a bourbon devalues the unique process and rich history which causes the spirit to receive its own classification in the first place.

Initially Tennessee Whiskey and Bourbon are made in the exact same way. They are both distilled from at least 51% corn, and go into charred new oak barrels to age. Where the spirits differ drastically however is in regards to what happens just before the freshly distilled clear spirit goes into the barrels. In Tennessee, it gets charcoal filtered.

Known as the Lincoln County Process, fresh whiskey is filtered through or steeped in charcoal chips before the whiskey goes into a barrel to age. And it seems no two Tennessee Whiskey producers complete the process in exactly the same way.

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At Jack Daniels, probably the most famous Tennessee Whiskey producer, Sugar Maple wood is soaked in 140 proof Jack, set on fire and reduced to charcoal, which is ground into bean-sized pellets. New whiskey is then poured through the pellets and placed immediately into barrels.

At George Dickel, Tennessee’s other famed whiskey producer, things are a bit different. Instead of filtering through the Charcoal, Dickel pours the whiskey into 13 foot vats and allows the whiskey and maple charcoal to soak together at a temperature of 40 degrees. The rationale for filtering at this frigid temperature is that Dickel claimed his whiskey always tasted better when it was made in the colder months of the year. After the soak, it heads to the barrel as well.

It’s unclear when exactly the Lincoln County Process was invented, but its creation has certainly helped to define Tennessee Whiskey. Charcoal filtering is a subtractive process. By filtering the newly distilled spirit through the charcoal prior to barreling, the process strips the whiskey of much of its harsh flavorings and creates a smoother, more easy drinking spirit.

Following the guidelines for making Bourbon, utilizing the Lincoln County Process and distilling the whiskey in the state of Tennessee are the requirements needed to label the product a Tennessee Whiskey. Technically these producers would be legally allowed to call their product Bourbon, since they follow all the legal guidelines and there is no requirement bourbon must be made in Kentucky, but, as any Tennessean will tell you, there is a difference and you can taste it.