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I’m often asked the question, what is bourbon anyway? If you’re a regular reader, you may know what makes bourbon technically “bourbon,” but frankly, there’s a lot of bad information out there, and most are just left trusting whatever they read on the internet. So first and foremost, I’ll link to the direct sources so you can read them for yourself. Second, I’ll kick this off by stating emphatically: I do not make the rules, I just try to make sense of them. What starts off as a simple concept becomes a tangled web of legalese. Is ignorance bliss, or do you really want to know how to define the one spirit we can call 100% American? In the words Morpheus posed to Neo in the movie The Matrix, will you choose the blue pill or the red one?

So let’s keep the definition of bourbon simple, and just copy verbatim from the Alcohol and Tobacco Tax and Trade Bureau (TTB) Beverage and Alcohol Manual, or BAM for short…which you’ll want to say emphatically with a “!” the next time you use it to drop some knowledge on somebody…BAM! The manual summarizes and clarifies the Code of Federal Regulations (though I will note it is currently being updated in some areas to maintain consistency with recent amendments to the Code, so watch for an update). We have to jump to BAM Chapter 4: Class and Type Designation (page 2):

Let’s start with the definition of “Whisky,” because the rest of the definitions refer to it:

WHISKY: Spirits distilled from a fermented mash of grain at less than 95% alcohol by volume (190 proof) having the taste, aroma and characteristics generally attributed to whisky and bottled at not less than 40% alcohol by volume (80 proof)

And more specifically, “Bourbon,” which is a subcategory under Whisky:

BOURBON WHISKY: Whisky produced in the U.S. at not exceeding 80% alcohol by volume (160 proof) from a fermented mash of not less than 51 percent corn and stored at not more than 62.5% alcohol by volume (125 proof) in charred new oak containers

You’ll notice a few things are missing from the requirement to be called bourbon:

  • “Kentucky” is missing because bourbon does not need to be made in Kentucky, even though the majority of it is by volume. It just needs to be made in the United States.
  • Anything related to bourbon’s required “age,” because there is no minimum age requirement for bourbon. If it meets all of the other requirements, as soon as it touches a new charred oak container, it becomes bourbon.
  • You don’t see any references to “American” or “white” oak. We can thank the marketing folks for this one, as the catchy “American” (it is bourbon after all!) term is used in so much marketing material, half of the country thinks that’s a requirement. While this is the case most of the time, the oak can be from anywhere in the world and can be any sub-variety of oak.
  • That’s right, “Barrels” is also missing from the equation, because the fact is bourbon can be aged in any charred new oak container. “Trojan horse” container aged bourbon anyone? But it just so happens that barrels are an age-old engineering marvel and they’re still the container of choice today.

Straight bourbon takes this a step further and layers on two additional requirements, however a lot of the media get “bourbon” and “straight bourbon” mixed up. This creates some confusion, especially when it comes to age requirements. Like the definition of just “Bourbon,” let’s take Straight Bourbon’s definition from the same source (page 2):


  • Bourbon whisky stored in charred new oak containers for 2 years or more
  • “Straight Bourbon Whisky” may include mixtures of two or more straight bourbon whiskies provided all of the whiskies are produced in the same state

For Straight Bourbon, if multiple whiskeys are blended together, they must all originate from the same state. This might seem benign, but we are starting to see a surge of companies blending bourbons distilled in multiple states to create a single product, and they cannot label them “Straight Bourbon.”

However, whiskey makers can label these multi-state blends “A Blend of Straight Bourbon Whiskies” or “Blended Straight Bourbon Whiskies,” as taken again from BAM Chapter 4 (page 5):

A BLEND OF STRAIGHT BOURBON WHISKIES OR BLENDED STRAIGHT BOURBON WHISKIES: A blend of straight whiskies produced in the U.S. consisting entirely of straight bourbon whiskies

Well, that sounds kind of like “Straight Bourbon Whisky” to me. But keep in mind the straight bourbons in the blend are allowed to originate from multiple states. And even more notable, unlike “Bourbon” and “Straight Bourbon,” “A Blend of Straight Bourbon” is allowed to have Harmless Coloring/Flavoring/Blending Materials (referred to as HCFMBs) added to it as detailed in BAM Manual Chapter 7: Coloring/Flavoring/Blending Materials (pages 9-11). Now this does not mean that all companies are doing this, because they are really just stuck with labeling requirements and basically get forced into this classification, but it’s important to know that they can. You might also notice that all non-straight whiskeys except for bourbon allow the addition of these HCFBMs. Bourbon, even if not labeled straight, does not.

I’ll go one step deeper on this and clear up what “Blended Bourbon Whisky” or “Bourbon Whisky - A Blend” means, because it’s very different from any other classification I’ve talked about here, even though it sounds pretty much exactly the same (do you need a drink yet?). The key to remember is the word “straight” isn’t anywhere in the title, so if you remember one thing, remember that. Here it is, again from BAM Chapter 4 (page 4):

BLENDED BOURBON WHISKY OR BOURBON WHISKY – A BLEND: Blended whisky produced in the U.S. containing not less than 51% on a proof gallon basis (excluding alcohol derived from added harmless coloring, flavoring or blending materials*) straight bourbon whisky

Mostly straight bourbon…but they can be nearly half something else. This product has pretty much gone to the wayside as consumers have become more savvy and bourbon production has increased dramatically, but the classification can serve as a major point of confusion for consumers.

Another major point of confusion is whether bourbon requires an age statement, and if so, when. You’ll notice we use the acronym “NAS” in a lot of our reviews, which stands for “No Age Statement” or “Non-Age Stated.”

I’ll clear up one point of debate once and for all: Any bourbon, whether straight or not, requires an age statement stating the youngest bourbon in the blend if it is less than 4 years old. When the whiskey maker excludes an age statement from the bottle’s label, they are telling us that no bourbon within that bottle is aged less than 4 years. Or at least that’s the rule.  

Somehow this requirement got tacked onto “Straight Bourbon” in countless articles, and then of course, the typical “rinse then repeat” ensued, creating an echo in the media suggesting this requirement only applies to straight bourbon. But that is not the case. In fact, it pretty much applies to all whiskeys, which you can read about in BAM Manual Chapter 8: Statements of Age. So now you know, when we note a whiskey’s age is “NAS,” that just means there is no age stated on the label, but we also know that the youngest whiskey in the blend is at least 4 years old. Now this assumes that producers and distillers follow the rules, which sadly does not happen 100% of the time.

The rules get even more complex for products that fall in the “Distilled Spirits Specialty” category, which is pretty much every finished whiskey nowadays. Many of which are labeled as “Straight Bourbon Finished in…” you fill in the blank. I personally enjoy the idea of finished whiskeys, but they can be a classification nightmare which I pointed out in a previous article - Bourbon: The Case of Mistaken Identity. And that’s just the tip of the iceberg. Block off the rest of your day and take a read through the official Federal Code of Regulations (CFR) Title 27 Part 5 and the recent Treasury decisions T.D. TTB-158 and T.D. TTB-176 that detail recent amendments to the Code, or search TTB’s Public COLA Registry, a database that provides access to information on Certification/Exemption of Label/Bottle Approvals (COLAs baby! …and not the kind you mix with Jack). As an added bonus you’ll get a one-up on new products that are (likely) headed to market, because they usually show up here first.

So…will it be the blue pill or the red one?

Written By: Nick Beiter

January 5, 2024
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