Whiskey Culture is a platform for exploration, fun, and, most importantly, education.

Today, we have a special guest article from Jeremy DeWitt, Distiller for 10th Mountain Whiskey & Spirit Co. They are distilling Colorado Whiskey that not only honors their craft but honors our Veterans through their philanthropic efforts.

Jeremy will discuss his craft and how 10th Mountain’s unique location and process help develop its proprietary flavor. However, this topic has a lot of nuance and information for whiskey enthusiasts, so we’ve divided it into two parts! Be on the lookout for Part II next week!

Flavor Development in Whiskey – Part I

Many factors contribute to the combination of flavors that make up your favorite whiskey. The mash bill lays the groundwork for determining the type of whiskey; the variety of different grains impacts the texture, sweetness, and spice. While the mash bill significantly impacts the finished whiskey’s flavor, everything from the distillery’s location to the bottling process builds on that foundation to develop the aroma and flavors you find appealing. These factors can be categorized into five primary sources contributing to the flavor development of whiskey: Location, Fermentation, Distillation, Maturation, and Bottling.

Location:

Where is the distillery? Is the climate hot or cold? How much does the temperature fluctuate where the barrels will be stored? What is the water source? The answers to these questions all play a role in the final result. A dry climate will cause more water than alcohol to evaporate from the barrels. The more the temperature fluctuates, the more it will cause the aging whiskey to expand and contract through the barrel’s staves, which will aid in the maturation process. Water is an essential ingredient in whiskey production, so the quality of the water source will also affect the finished product. Suppose a distillery is using a spring or well for a water source. In that case, the whiskey may benefit from the mineral content more than a distillery located in the city using a reverse osmosis system to filter their source water.

The 10th Mountain Whiskey Difference: Our distillery’s elevation and dry climate cause more water than alcohol to be extracted from the aging barrel than in more humid environments. The fluctuating temperatures we experience year-round in the Rockies allow the spirits within the barrel to expand and contract through the pores of the barrel staves, which appears to expedite the maturation process by extracting sugars and flavor components from the wood and introducing more air for oxidation/esterification of the aging whiskey. In addition, the Rocky Mountain snowmelt we use to make our whiskey has an abundance of natural minerals that have been known to produce a lighter, sweeter spirit.

Fermentation:

Flavor is further developed during the fermentation stage of production. Yeast converts the fermentable sugars into ethanol and carbon dioxide during this stage while simultaneously producing hundreds of secondary metabolites that influence the aroma and taste. There are many different yeast strains, and these metabolites can vary significantly between strains; therefore, the selection of yeast strain is an important consideration. Fermentation time and pH also play a role in flavor development. As the fermentation progresses and the pH becomes more acidic, the yeast rests, producing more flavor components.

The 10th Mountain Whiskey Difference: We allow our fermentation to run a full six days. The longer fermentation times allow for the formation of lactic acid, which can form esters like ethyl acetate giving the spirits a creamy, buttery flavor. Lactic acid bacteria are also known to hydroxylate unsaturated fatty acids from yeast, which are then esterified into lactones, giving the spirit fruity flavors and aromas. The longer fermentation times also allow more time for lipases to break down triglycerides from the yeast, producing fatty acids, which are then available for esterification of fusel oils.