Lincoln County Process

The Lincoln County Process is a step used in producing some Tennessee whiskeys. The whiskey is filtered through, or steeped in,charcoal chips before going into the casks for aging. The process is named for Lincoln County, Tennessee, which was the location of Jack Daniel's distillery at the time of its establishment; subsequent redrawing of county lines means that none of the distilleries currently using the process are located in the county for which the process is named.

The charcoal used by Jack Daniel's is created on site, from stacks of two by two inch sugar maple timbers called "ricks". They are primed with 140 proof Jack Daniel's, and then ignited under massive hoods that help prevent sparks. Once they have reached the char state, the ricks are sprayed with water to prevent complete combustion. The resulting charcoal is then run through a grinder to reduce it to consistent bean-size pellets. These are then packed into 10-foot (3.0 m) vats, where they are used to filter impurities from the 140 proof whiskey, after which the whiskey is reduced with water to 125 proof for aging.

The George Dickel distillery uses deeper (13 foot) vats and distills only to 135 proof. Dickel also chills its whisky to 40 degrees F (5 °C) before it enters the vats, and allows the whiskey to fill the vats instead of just trickling it through. The distillery claims that these differences yield a better filtering process as Dickel found he made more pleasing whisky during the cooler winter months.

Collier and McKeel, made in Nashville, claims to drip whiskey through "several feet" of sugar maple charcoal made from trees cut by local sawmills.

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