This Is How Bourbon Is Really Made

Not everyone loves a smooth glass of Kentucky bourbon. That distinct flavor is one you'll either love or hate — but if you love it, there's a good chance you'll love it forever, and you'll be a stalwart whiskey drinker for life. And more and more drinkers are jumping on the bourbon train these days; in fact, some might say that there's a "bourbon boom" occurring, with bourbon production and demand at its highest in decades.

But how exactly does that whiskey make its way from the distiller to your liquor store shelf? The process is an art form and, if you've never had the pleasure of traveling the Kentucky Bourbon Trail, one that you might not be that familiar with. Sure, you know that there are barrels involved and you're pretty sure that some corn and something called a "mash" is included, but what are all the necessary steps for getting from grain to one really great glass of whiskey?

Here are the 12 primary factors that go into making your favorite bourbons.

Each whiskey, including bourbons, starts with a mash bill, which is basically the master distiller's recipe for that particular whiskey. It tells the distiller exactly what grains need to go into the whiskey from the start, in what ratios. However, remember that in order for a whiskey to be a bourbon, at least 51% of that grain ratio must be made up of corn. Other grains that can be used include malted barley, rye, and wheat. The ratios of each impact the taste of the final product. As Southern Distilling Company notes, a whiskey with more corn will have almost a syrupy flavor, while rye-heavy whiskeys are more savory. Bourbons with a heavy portion of malted barley will typically taste maltier and toffee-esque, while bourbons with a heavy amount of wheat will taste clean, with a soft, sweet undertone.

The final ratio and mash bill depend entirely on the individual distiller. The only rule, again, is that they include at least 51% corn.

After the bourbon mash is created via the perfect quantities of grains, as well as the right yeast and water, it's left to ferment. The fermentation process doesn't take long; MasterClass says from one to two weeks, but other distillers are finished with fermentation in as little as three days. The fermentation process allows for all of the ingredients to break down on a chemical level, creating alcohol.

Often, the distiller will add more yeast and sour mash around this time. The sour mash is a mash liquid that's been leftover from a previous batch of bourbon mash and helps the new mash reach the correct pH levels. Think of it as similar to a sourdough starter or kombucha scoby. You need a little bit of something old, to make something new. The tradition of using sour mash came about in the 1800s, to help distillers produce a consistent product over multiple batches. Today, every major U.S. whiskey distillery uses the sour mash process, but it's not entirely necessary to create a bourbon and it is possible to find some micro-distillers who do not (via Whisky Magazine).

After fermentation and one round of distillation are complete, the remaining mixture is strained, separating the liquids and solids. The liquid can be used as that sour mash that's added to new mash later, but the solids have a very different destination.

While some distillers may toss the solids, known as distillers' grain, others will ship the grain to farms, where it's used as livestock feed (via CNBC). While that may seem a little odd and possibly harmful to the chicken and cows for which the feed is intended — after all, this grain mixture has been soaking in a bourbon-adjacent liquid for days, could it possibly result in some very inebriated farm animals? — research says the mixture is actually a very healthy and low-cost option for farms. The Iowa Corn Growers Association notes that distillers' grains are filled with protein, fat, minerals, and vitamins, and, since about 90,000 tons of distiller's grains are produced in the United States each week, the mixture is readily (and affordably) available.

After the bourbon is in the barrel, it sits there. For a while. And just like there are a lot of rules regarding what goes into a bourbon, there are a lot of rules regarding how long a bourbon is aged. As Southern Kitchen states, a bourbon must be aged for at least two years but no more than four years if it's to be called a straight bourbon whiskey. If a bourbon is going to be called a bottled-in-bond bourbon, it must be aged for at least four years. If a bourbon is a mixture of multiple bourbons aged for multiple timespans, the number on the bottle should reflect the youngest bourbon's age.

Typically, the longer the bourbon stays in the barrel, the more flavor it develops. However, that's not always the case. Most bourbons hit peak flavor around five to 10 years and other factors, such as environment, also play a role in developing the flavor once the bourbon is in the barrel.

So beyond just knowing how long a barrel of bourbon has been sitting in the rick house, how does a distiller know the bourbon is done? By tasting it, of course. The master distiller at a distillery will sample bourbons directly from the barrel and decide which are ready to be bottled. Master distiller Marianne Barnes told CNBC that she must be able to identify the nuances of flavor profiles of each of her distillery's brands, as well as be able to identify a barrel's proof and any defects upon tasting.

But tasting all that bourbon isn't as fun as it may sound. Barnes told the publication that she's not allowed to smoke, can't wear perfume on the job, and does "a lot of spitting." She also has to recalibrate her senses every once in a while, using scent jars to ensure she's accurately picking up on flavor notes like oak, cedar, and pepper. She can reportedly do 50 tastings of a 140-proof bourbon before her mouth goes numb, compared to the average drinker's six tastings.

From there, the bottled bourbon is shipped to your favorite local liquor store and then it's up to you to properly store your bourbon at home, so that all of that hard work on behalf of the distillers, coopers, and others doesn't go to waste.

Heaven Hill Distillery recommends that you store your bourbon in a cool, dark spot, away from heat and sunlight. Additionally, always store your bourbon bottles vertically, never horizontally, and make sure to use a sturdy shelf, where bottles won't be in direct contact with a floor or wall. Likewise, don't store your bourbon bottle near an oven, in the attic, or in the back of a car. You want to keep the bottle somewhere between the upper 60s and lower 70s. If you're collecting whiskey that you aren't putting on display immediately, consider storing it on industrial-style shelving in a (clean, dry) basement — though we also totally understand if you don't want to wait to drink that whiskey long enough to start a collection!