What is the difference between bourbon and sour mash whiskey?

As a sommelier and brewer, I can provide you with a detailed explanation of the difference between bourbon and sour mash whiskey. Let's start with bourbon.

Bourbon is a type of whiskey that is exclusively produced in the United States. It is often associated with the state of Kentucky, but it can be made anywhere in the country. To be classified as bourbon, it must adhere to strict regulations. Firstly, it must be made from a grain mixture that is at least 51% corn. The remaining grains can include malted barley, rye, or wheat.

Another key requirement for bourbon is aging in charred oak barrels. These barrels give bourbon its distinct flavor and color. The aging process must take place in new, charred oak containers. However, there is no specific time requirement for how long bourbon should be aged. Some bourbons are aged for a few years, while others are aged for much longer, resulting in a more complex and refined flavor profile.

Now, let's move on to sour mash whiskey. Sour mash refers to a specific production method used in making bourbon. Not all bourbons are sour mash, but all sour mash whiskeys are bourbon. Confusing, right?

The sour mash process involves using a portion of previously fermented mash to start the next batch. Essentially, a small amount of the previous batch is added to the new one to help with fermentation. This helps to maintain consistency in flavor and fermentation. It is similar to the concept of using a sourdough starter in bread-making.

The use of sour mash in bourbon production is not mandatory, but it is a common practice that has become synonymous with the bourbon-making process. It can contribute to the overall character and flavor profile of the bourbon, adding a subtle complexity and balance to the final product.

To summarize, bourbon is a specific type of whiskey that is made in the United States and must be composed of at least 51% corn. It is aged in charred oak barrels, which gives it its unique flavor. Sour mash, on the other hand, refers to the production method used in making bourbon, where a portion of previously fermented mash is used to start the next batch. All sour mash whiskeys are bourbon, but not all bourbons are sour mash.

In my personal experience, I have had the opportunity to taste a variety of bourbons and sour mash whiskeys. Each one has its own distinct characteristics and flavors. Some bourbons have a rich, caramel sweetness with hints of vanilla and oak, while others may have more pronounced spice notes from the rye in the grain mixture. Sour mash bourbons, with their added complexity from the sour mash process, can offer a different dimension of flavors, often with a smoother and more balanced profile.