Scotch is truly the whisky of the world. While American whiskey may be the go-to whiskey for cocktails, if you order a whiskey just about anywhere outside of North America, you'll get a scotch (and the whisky won't be spelled with an "e").
Scotch can only be made in Scotland and barely is its primary flavoring grain, though wheat and corn play important roles as well. Scotch is known for having a smoky, campfire-y flavor which comes from fires of burning peat to dry the barley. This is why you sometimes hear scotch described as “peaty” (more on that below). But it's important to remember that not every scotch tastes smoky. Some are very subtle with notes of honey, flowers, and dried fruit. And those that are smoky, vary greatly in intensity.
Single Malt vs. Blended Scotch
The two main types of scotch are single malt scotch and blended scotch, though there are some others. Single malts are made from 100% malted barley in one distillery and are generally more intense, longer aged, and more expensive. Blended scotches are a blend of 15-40% single malt scotch and 60-85% grain whiskey (technically called single grain scotch) made mostly from wheat. Grain whiskey is much lighter and cheaper to produce thus blended scotch tends to be milder, easier to drink and less expensive, making them great for cocktails.
It’s tempting to view single malts as superior, purer expressions of scotch and blends as second-tier, budget options only fit for topping with soda water, but that’s a misguided assumption (one I admittedly once held). The two are apples and oranges. A single malt is a singular expression of a distillery. It’s meant to be more pointed and fuller flavored. A blend tries to bring multiple scotches and flavors into balance. That's why it can work better for mixing; it plays well with others.
The rules only stipulate that a scotch must be aged for at least 3 years in oak barrels. Any kind of barrel, or barrels, can be used which leads to lots of different appearing on labels. Over 90% of scotches are aged in are ex-bourbon casks. The other 10% are largely ex-sherry, which used to be much more common, and are still utilized by many well regarded single malts.
When I first heard about scotch being aged in recycled barrels I assumed these casks would be jam packed with extra flavor soaked in the wood. But used barrels actually impart less flavor than new ones because first spirit seeps out the bulk of the wood’s strongest flavors. But this isn't a bad thing. The less aggressive flavors of used barrels is one reason scotch can be aged for longer periods without becoming dominated by oakiness, and it allows other subtitles to come through.
Ex-bourbon barrels are so common because they - along with most other American whiskies - can only be aged in brand new oak barrels, so there are plenty of barrels leftover. New American oak barrels impart flavors things like coconut, vanilla and toffee, aka the primary flavors found in bourbon. Used American oak barrels will still impart these characteristics, but less dramatically and they will be a bit drier overall.
A scotch aged in a sherry cask - which used to be predominantly made from European oak, but today is mostly American oak - is very distinctive. You can expect rich flavors of dried fruit and a hint of sherry’s signature nuttiness which becomes increasingly apparent the the older the scotch gets. Some would say these scotches are sweeter, but I think it's more that the fruit is suggesting sweetness, rather than actual sugar content. The Macallan line is a quintessential example of sherry cask scotches.
Other Barrel Options
A barrel can be reused multiple times, but each time it's impact will lessen, like reusing a teabag. After three fills a cask is pretty much spent. Though they can be "rejuvenated" by scraping off their inner layer and being re-toasted or re-charred to start fresh.
The options don’t stop there. Some scotches are aged in multiple barrels. Balvenie Doublewood is a marriage of bourbon and sherry casks. Others are “finished” in a barrel for a few months up to a couple of years to add a final layer of complexity. Rum, port, madeira, sherry casks, among others, are commonly used for finishing.
I think of the choice of which barrel(s) to use - bourbon, sherry, 2nd fill, 3rd fill, finished, rejuvenated, or a combination - and for how long, as all part of a scotch's recipe. With such a wide variety, a producer can go so many different ways and I think that is the primary reason why scotch is the most diverse whisky in the world.
Single malt comes from one of six regions: Islay, Highlands, Lowlands, Speyside, Campbelltown and the islands. The most prominent are Islay, a small island off the southwestern coast which has the peatiest scotches and the inland regions Speyside and Highlands where the scotches are less smoky and range from light and grassy to rich and fruity.
Blended malt is a less common style. blend single malts from multiple distilleries.
Single Grain or Grain whiskey usues non-malt grains - corn, wheat, rye - as well as malted barley. It is used mostly in blends.
How Scotch is Made
This is where a scotch can acquire those smoky campfire flavors. The final step in the malting process is to dry the barley in to a kiln to stop it from fully germinating. Sometimes this kiln is fueled with peat. Peat is partially decomposed plant matter found in bogs and wetlands that's basically on it's way to becoming coal. But coal takes 300 million years to form, peat’s only had a few thousand. The smoke from the peat fires penetrates the barely with a flavor that it will carry all the way to the bottle.
Peat is cut from the earth in bricks, which are then dried. Scotches that add peat to their kilns are called "peated" and while this method originated, and is most common, in Scotland, it is not exclusive to scotch. Other whiskies are peated including some from Japan, Ireland, a few in the U.S. and beyond.
For hundreds of years peat was vital to rural parts of Scotland because it was the only fuel option. Back then using it to stoke the barley kilns was purely out of convenience. But even after modern transpotation made coal wildely available, peat continued to be used for scotch production because many had come to love and associate it’s distinctive flavors with scotch. It had become a proprietary characteristic.
Phenols and PPM
Burning peat essentially flavors the smoke. Those flavors will vary depending on how deeply the peat was cut - in some areas it goes down over 20 feet - and where it was formed - different vegetation will develop different peat with different flavors. The type of compounds that carry this smoky flavor are called phenolic compounds. Their concentration can be measured in ppm (phenolic parts per million) to give you a gauge on how smoky your scotch will be. While this is not generally listed on the bottle, recently some brands have begun to promote their higher levels of ppm. A very peaty scotch with have a ppm in the 30-50 range, Bruichladdich's Octomore proudly owns the highest at 169 (!). But I have no doubt that another brand will eventually top that, in spirit of one upmanship.
Personally, I think the obsession with having the peatiest scotch possible is a little excessive, like having the driest martini, the rarest steak or the hoppiest IPA. It seems to be more about bragging rights than actual flavor preference. Then again, I do love rare steaks and super hoppy IPAs. So maybe I’m as black as that kettle over there.
There are a slew of variations on how a pot still can be constructed and scotch distillers meticulously take all of them into account. The size of the still, how it’s heated, how long the neck is, the angle the lyne arm, which type of condenser is used, and a host of other factors are considered. There are famous accounts of distillers going as far as to recreate a particular dent in a new still to mimic an old one, because they don’t want to loose a certain characteristic the old dent might have been contributing. By law scotch only can be distilled up t0 94.8% ABV, which is pretty much the maximum proof possible. Most single malts will be distilled to 65-75% ABV.
All this is aimed at capturing or passing up congeners to produce the type of distillate a distiller is after - heavier, lighter, richer, oilier, more delicate, etc. From there, the distiller will make a cut - how much and the head, heart and tails to use - to decide which of those congeners will move on to the barrel aging process. There these compounds will go through yet another transformation and make their final mark on the scotch’s flavors.
In addition to the divide between single malts and blends, scotch offers an incredible diversity of flavors and styles, far wider than the you’ll find with and other whiskey or brandy. From different regions, different casks, the use of peat - or lack thereof - and a host of other variables, scotch production can take many twists and turns. Here we’ll dig deeper into some of those and how to navigate them from bottle to bottle.
Other Scotch Categories
Blended Malt Scotch - A blend of single malts, but from different distilleries. This was once also referred to as a vatted malt or pure malt.
Single Grain Scotch - Made from primarily wheat and sometimes corn, all in one distillery, like single malt scotch. Mostly used for blended scotch, as mentioned above.
Blended Grain Scotch - A blend of single grain scotches, but from different distilleries, like a blended malt.
Base Ingredient: Malted Barely
Scotch's bedrock grain is malted barley. It is used exclusiely in single malts and is present in smaller quantites in grain whiskies. Barely creates a distillate that is a bit drier than other grains. Malted, refers to a technique that break down barely's starches into simple sugars for the yeast to eat and convert into alcohol. This is done by steeping the barley in water to "convince" it to begin germinating, more on that here. In addition to scotch, malted barely is used in beer as well as whiskies all over the world.
Wheat and Corn
For grain whiskey used in blends wheat in the primary grain, it supplanted corn in the 1980s, which is still sometimes used. Both grains create distillates that are lighter and a bit sweeter which is perfect for blended scotch.
Time and Price-point
Scotch's capacity for longer aging is one of the primary features that makes this spirit is so remarkable. Though the minimum age is 3 years, many are at least 8-10 years old and plenty stretch into the upper teens and beyond.
One reason for this is the less potent used barrels scotch is aged in, as mentioned across. Another is Scotland's climate which ranges from cold and wet to temperate and humid, causing the whisky to mature very slowly. The higher humidity also means more alcohol evaporates than water as part of the angel’s share, so the proof inches down over time.
This longer aging is also a big reason why scotch is among the most expensive spirits in the world. It makes sense, time is money of course.
But an older scotches aren't necessarily better. Of course, they can be incredible. The best ultra aged Scotches possess remarkably deep and subtle complexities that can only be achieved through prolonged maturation. But I’ve known plenty of cases where a 12 year old scotch is better than it’s 18 or 20 year old counterpart. These “younger” scotches are often more vibrant, livelier and regarded by many to be the true indication of a scotch’s quality.
Heavily aged scotches can take on too much wood, masking or dampening the distillate's core flavors, which always be a primary flavor. They may be smooth and rich, but ultimately they're less interesting. So don’t too swayed by the number in the bottle. In then end, as always, trust your palette.
A row of copper pot stills ready to pump out some scotch.
Courtesy of Wikimedia Commons
Scotch in Cocktails
Scotch is a challenging spirit to mix with, even when using a milder blended scotch. It's strong, disitinctive flavors can easily clash with or downright dominate other ingredients. But finding a good scotch cotkail is worth the effort. For starters, try one of the handful of classics, my favorites are the Rob Roy (a scotch Manhattan), the Bobby Burns (a Rob Roy with a little Benedictine) and Sammy Ross’ gingery modern classic, the Penicillin.
Maturation & Barrel Aging
By many estimations, the barrel is where 70% of a scotch's distinctive flavors come from. While many areas of scotch production are tightly regulated,
when it comes to barrel aging, it’s pretty much open season. This and the following below also mostly applies to Irish and other international malt whiskies as well. For a deeper look at the inner workings of barrel aging visit the maturation page.
Fermentation typically takes 2-3 days, though some go for longer, to create scotch denser fresh fruit flavors from additional ester creation. After fermentaion, it's time for the still.
Single malt scotch must be distilled at least twice in copper pot stills, a few do three runs. Grain whisky is almost always made in a column still which to maximizes volume and creates a lighter spirit that will serve as the backbone of a blend. Each still best accomplishes what is required of each style, but most of the romance in scotch distillation occurs in the pot still.
Blending scotches, whether it's malt and grain, all malt, or all grain, is a form of artistry all unto itself. A popular metaphor likens it to a composer constructing a symphony, with each scotch representing a different section in the orchestra, trying to bring them together in perfect harmony. Sometimes a blend will contain over 30 whiskies from varying regions, distilleries and age statements. If a blend, or a single malt for that matter, has an age statement on the label it will always be of the youngest Scotch in the bottle, which is generally the practice throughout the spirits industry.
In addition to being better for mixing, blended scotch's
accessibility makes it an excellent introduction to the scotch category, which can sometimes be a little intense for the uninitiated. You can read more about blended scotches, including brand recommendations here.
Scotch may have coloring added, and many do. Distiller’s caramel, aka E150A, is typically used. For a spirit with such a pedigree this is surprising to many, it was to me. It seems to challenge scotch’s authenticity. But it is not meant to effect the flavor or add any sweetness. It's just to give the whisky a darker color and the appearance one would expect from a spirit that spends as long in a barrel as scotch does. The recycled barrels scotch usues imparts less color, bourbon for example is the color of rich mahogany after about a year.
Most scotch is bottled at or around 40-43% ABV, a few degrees lower than American whiskey’s average of about 45%. Though some scotches are sold at cask strength which goes as high as 60% ABV.
Who Makes and/or Owns the Brand?
As consumers, all we have to identify a scotch by is the name on the label, which is simple enough. But if you want to know who is actually making the product, where they are making it and who owns it, it’s not always so clear.
Brands: Distilleries vs Blenders
One way to begin to parse it out is with single malts, the name on the label and the distillery are the same. The distillery is the brand. If you look at a map of scotch distilleries, you’ll see the names of your favorite single malts dotting the landscape. With blends, the name on the label just a brand, there’s no, say, Johnny Walker distillery. Though you could visit the disitlleries where parts of Johhny Walker are made, like the Cardhu disillery in Speyside. Of course there are plenty of distilleries not making single malts, but grain whisky to be used for blends.
Each single malt having it's own specific disillery is one of my favorite things about scotch. I find it very comfroting. It gives me a sense of connection to the distillery and its whisky. American whiskey for example is highly conglomerated and mostly comes from only eight distilleries. You won’t recognize as much on an American whiskey distillery map.
The Corporate Owners
But the idea of small all these small family owned single malt distilleries operating independently is not quite as romantic as it seems. Most of them, as well as blend brands, are usually owned by a larger company. For example, Diaego owns the Johnnie Walker brand and the Lagavulin, Talisker and Oban distilleries. A list of corporate owners of distilleries can be found here.
Then there are independent bottlers, who purchase scotch from a distillery and age, sometimes blend and bottle it under their own label, usually listing the distillery where it originated. These a source of controversy within scotch aficionado corners because they don’t always play by the rules. But I like all things of that nature, I think a little boundary pushing can be healthy. That is, until it isn’t.
One example of an independent bottler that’s a force good in the scotch industry, in my opinion anyway, is Compass Box. It was started by John Glaser, who used to be the International Marketing Director at Johnnie Walker. He uses a lot of unconventional aging and blending techniques and offers a dizzying array of different bottlings, which are all interesting and delicious. They are also completely transparent about their operation. So much so that’s they’ve broken the law. But Compass Box is pushing back, advocating for more freedom to be honest and transparent in the scotch industry, which I find very inspiring. Knowing more about what’s in our glass of scotch and how it got there would be better for all of us, especially us nerds.
An look at the single malt distilleries on Isaly.