Whiskey. More flavorful than vodka, better straight than gin, more authoritative than wine, more refined than beer. As much at home in an upstate, backwater bar as a San Francisco tech god’s top shelf, or a Kentucky colonel’s Mint Julep cup.
It changes names (and spelling) depending on where it’s made and what it’s made from, but it all falls into the same overarching family.
At its very heart, all sentimentality stripped away, whiskey is simply an alcoholic beverage made from fermented grain mash. It has to be at least 40% alcohol (80 proof) and no more than 94.8% alcohol (189.6 proof, a.k.a. the worst night of your life).
Every other qualification for whiskey – single malt, single barrel, blended, bourbon, rye, scotch, and on and on – it all comes from three basic things:
What grains are in the mash.
What geographic area it comes from.
What fermentation process it undergoes.
That's it.
Or rather, that’s the science, anyway. Beyond that science is pride. It’s drinking Jack Daniels in a Nashville honky tonk. It’s the time an attractive bartender took a shot with you because you asked for Jameson instead of Dragonberry Bacardi or Strawberry Svedka. Whiskey is the drink every man aspires to actually enjoy, and when he does, he aspires to learn more about it.
And that’s our goal here: to give you some basics, so when you read a label, you know what it means, and a little about how it might taste.
The Grains
Whiskey starts with grains, which are soaked in hot water – that's called the mash. The hot water extracts sugars from the grains, which can later be fermented to create alcohol.
The type of whiskey, and the qualifications that get tacked on, come primarily from the type (or types) of different grains used in this step. There are a few different options, most notably including:
Malted Barley – Contributes some slightly roasty notes and a dry finish, but isn't too flavorful on its own. It's usually only used as a small percentage of any whiskey, more so for its fermentability than its flavor, but Scotch is a notable exception.
Corn – Strongly sweet at first, but mellows significantly the longer the resulting whiskey is aged.
Rye – Spicy and aggressive, with notes of black pepper and cinnamon that get more intense throughout the aging process.
Wheat – Soft and light, contributing a much subtler flavor to the final product. Generally, this simply allows the flavors of the other grains used to shine more brightly.
The mix that a distiller decides on – say, 75% corn and 25% wheat – is called the grain bill. Different distilleries play around with this a lot in an effort to calibrate the perfect taste that works for them.
Also worth noting is that barley is the only grain used in whiskey-making that's malted. So malt whiskey means 100% barley was used, and anything else is considered grain whiskey.
The Barrels
A whiskey’s interaction with its barrel (a.k.a. cask) is a key component to how it turns out, affecting everything from flavor balance to color. Oak is the only wood used for these barrels. Partially for practical purposes like its strength and size, and partially for the fact that unlike pine, it doesn’t contain thick, seeping resins.
There are several other very innate chemical reasons oak is used, involving things like cellulose, tannins, acetals, and other components that will quickly make you regret asking “why oak?” in the first place. But all you really need to know on the chemical side is that the wood contains things called vanillins, a kind of flavorful oil that gets drawn out during the aging process. Beyond that, suffice it to say that the kinds of oak used in whiskey barrel making add desirable qualities and purify undesirable qualities in the finished product.
There are a few different sub-types that affect the whiskey's final flavor and classification:
American Oak – A relatively new addition to the whiskey scene, having been first used around WWII for post-prohibition economic reasons. They've since skyrocketed in popularity, and now 90% of the world's whiskey is aged in these. They're ideal because the trees mature quickly, pack a high concentration of vanillins, and grow with tall, straight, sturdy trunks that are easily shaped into barrels.
European Oak – This is the traditional option, having been used for Scotch and Irish whiskey since the early 1800s. English, Scottish, Spanish, Russian, and French oak have all been used at one time or another, each with their own unique tradeoffs. French oak barrels (having been previously used for wine) and Spanish oak barrels (having been previously used for sherry) are somewhat common these days, but more for finishing than anything else.
Japanese Oak – Japanese whiskey is a small but growing part of the world whiskey scene, and this type of wood, also known as mizunara oak, is what the stuff is usually aged in. The wood has a huge concentration of vanillins, which lends a uniquely delicious flavor, but is also very prone to leaking and damage. To compensate, Japanese whiskey is often aged in sherry (French oak) or bourbon (American oak) barrels first, then transferred to Japanese oak towards the end of the process.
Which type of barrel a distiller uses doesn't matter nearly as much to the final classification of the whiskey as the grain bill does, but there are a few notable exceptions. Bourbon, for example, must be aged in brand new (a.k.a. first-use) oak barrels that have been charred on the inside.
And you may run into whiskeys (often Scotch) labeled as single cask or single barrel. That means instead of mixing a bunch of different barreled whiskeys together for a balanced and consistent flavor profile, the distiller stuck with only what was in a single barrel.
The label on a bottle of single-barrel usually has a batch and barrel number, because no other whiskey produced now or in the future is likely to have the exact same flavor profile as that cask. This is a double-edged sword. If you really like Glenfiddich, you know that the next bottle you buy will taste almost exactly like the last because a huge number of barrels have been masterfully blended to achieve a dialed-in taste. But once a single cask whiskey is gone, so is its unique flavor profile.
The Regions
As with any fine food or drink, the specific region a whiskey is produced goes a long way in determining its qualities. A Scotch made in Speyside will taste patently different than one from Islay. Ask a Tennessee whiskey diehard, and they’ll say the same is true for that particular branch of the bourbon family. But in (very) general terms:
Scotch is made in Scotland, in one of five specific regions.
Irish whiskey is made in Ireland.
Bourbon is made in the United States, usually Kentucky.
We’ll get into the detailed differences between these (and other) whiskeys in a separate article, but for our current purposes it’s worth noting that the type of whiskey produced in a particular place is largely based on the available grains and the local soil profile.
Rye and corn were initially much easier to grow in America than barley, so bourbon and rye whiskey were born out of necessity. In Scotland, the ubiquity of peat bogs and the age-old use of peat for a heat source is inexorably tied to the smoky, vegetal flavor of Scotch.
Other, more nebulous factors can shape the whiskey of a region, too. Irish whiskey, for example, has some of the least stringent laws in the world of whiskey classification. If you're so inclined, you can trace how the whiskey character of Irish distilleries shifted and grew throughout history with wars, revolutions, and political and economic groundswells, all the way up until today.
In the next installment, we’ll break down the different types of whiskey – their defining characteristics, points of origin, flavor profiles, and what unique combinations of the above factors each one uses. Until then, raise a glass to your newfound knowledge and drink up.
Cheers.