What is Tennessee sour mash?

Answered by Joseph Vos

sour mash is a unique and traditional method of producing . It is a process that involves using a portion of the mash from a previous batch to start the fermentation of the next batch. This technique, similar to a sourdough starter in baking, can result in a distinct flavor profile that sets Tennessee sour mash bourbon apart from other bourbons.

The sour mash process begins with a mixture of grains, typically consisting of corn, , and malted barley. These grains are ground and combined with to create a mash. is then added to the mash, which converts the sugars in the grains into through the process of fermentation.

In the case of Tennessee sour mash bourbon, a portion of the mash from a previous fermentation is added to the new mash. This “backset” is essentially the leftover liquid from the previous batch, which contains residual yeast and other compounds. By adding the backset to the new mash, it helps to regulate the pH levels and also introduces a unique blend of yeast strains that have been kept alive and active over many generations.

The use of backset in the sour mash process serves several purposes. Firstly, it helps to create a consistent environment for fermentation, as the pH levels are maintained within a desirable range. This can result in a more predictable and consistent flavor profile in the final product. Secondly, the introduction of the yeast from the previous batch can add complexity and depth to the flavor, as different yeast strains can produce different flavors and aromas during fermentation.

One of the key benefits of the sour mash process is its ability to create a more stable and controlled fermentation environment. The presence of the active yeast from the previous batch helps to inhibit the growth of unwanted bacteria and wild yeast, which can introduce off-flavors or spoil the fermentation. This can be particularly important in warmer climates, where the risk of bacterial contamination is higher.

It's worth noting that Tennessee sour mash is specific to the state of Tennessee and is closely associated with the production of Tennessee whiskey. While other types of bourbon can also use a sour mash process, the term “Tennessee sour mash” is often used to refer specifically to whiskey produced in Tennessee.

Tennessee sour mash is a traditional method of producing bourbon whiskey that involves using a portion of the mash from a previous batch to start the fermentation of the next batch. This process helps to regulate pH levels, introduces unique yeast strains, and creates a more stable fermentation environment. The result is a bourbon with a distinct flavor profile that sets it apart from other bourbons.