Love it or hate it, it’s undeniable that whiskey is a fascinating drink with a rich history. We’ll bet you’re here because you’re firmly in the 'love it' category and interested in diving deeper into the so-called 'water of life'.
Here we’ll teach you all about the different categories of whiskey.
What is whiskey?
Whiskey is an alcoholic spirit based on a mash bill of grains, which is fermented and then distilled. The distilled liquid is typically then aged in wooden casks.
Depending on the type, whiskey can be made using many different ingredients. Usually this means fermenting a mash bill of barely, rye, wheat and/or corn. Unique flavours are instilled using a variety of techniques, with the most common differentiator being the casks used for ageing. The type of wood the cask is made out of, whether or not its been charred, and even other spirits that may have been previously stored in the cask, will all have an impact on the whiskey’s flavour profile.
One of the first things you might notice about the different categories of whiskey are the different ways of spelling whiskey – or, indeed, whisky. The spelling is largely arbitrary and doesn’t make a great deal of difference, but in general, Scottish, Canadian and Japanese distilleries all label their product as whisky, while Irish and US distilleries label theirs with an ‘e’ (spellings will alternate accordingly below).
Different types of whiskey
There are many types of whiskey, but they can be most succinctly categorised by their countries of origin. The world’s 5 leading whiskey-producing nations are Scotland, Ireland, the US, Canada and Japan.
Scotch is often considered the benchmark of quality whisky and its distillation is strictly regulated. There are several categories of Scotch, but all must be distilled in Scotland and aged there for at least 3 years. All Scotch whiskies are distilled as single malt or single grain whiskies, but they’re often blended.
A single malt must be made solely from malted barley and at a single distillery. When two or more of these whiskies are blended, the whisky is labelled a blended malt whisky.
A single grain whisky is (perhaps confusingly given the name) distilled from a mash bill using both malted barley and additional grains. Like single malt, it must also be made at a single distillery. When two or more single grain whiskies are blended, the whisky is labelled a blended grain whisky.
Single malt and single grain Scotch whiskies can also be blended. Such a blend will be labelled a blended Scotch.
Scotch whiskies are very diverse in flavour. The 5 official distilling regions of Scotland – Highlands, Lowlands, Islay, Speyside and Campbeltown – all have their own characteristics and it’s common practice to age Scotch in barrels previously used to age other spirits, such as sherry or bourbon.
Mash preparation will also affect the flavour of a Scotch. For instance, by drying the barley over a peat fire before creating the mash bill will add a smokier aroma, while browning the residual sugars in the mash bill will give the Scotch hints of baked bread.
Similarly to Scotch, Irish whiskey must be distilled in Ireland and aged there for at least 3 years. From there, however, Irish whiskey is less strictly regulated.
In theory, that means you might have less idea of what to expect when trying a new Irish whiskey compared to trying a new Scotch, but there are some common characteristics. Most Irish whiskey is triple distilled and with enzymes added to converts starches in the mash bill to sugars prior to distillation. Consequently, Irish whiskeys tend to be smoother than more complex, earthy Scotches.
Irish whiskey was once widely regarded as the best in the world. Unfortunately, like much else in the country, the whiskey industry was devastated by economic turmoil in the 19th century and has never really recovered. Nevertheless, there’s still a lot of great whiskey to experience should you get a chance to visit. Check out this guide to the best places in and around Dublin to discover Irish whiskey.
American whiskeys fall into two main categories depending on the dominant grain used in its mash bill: rye whiskey and bourbon. According to US law, the mash bill of rye whiskey must contain over 51% rye and the mash bill of bourbon must contain over 51% corn (although most contain over 70%). Both are aged in charred oak barrels.
Unsurprisingly, the grain used has a significant effect on the whiskey’s flavour. Rye will produce a spicier, more complex flavour profile, whereas the use of corn makes bourbon the sweeter, smoother option.
But what about Tennessee Whiskeys, like the globally recognised Jack Daniel's? Tennessee Whiskey is an offshoot of Bourbon, but its distillation is even more tightly regulated. To qualify as a Tennessee Whiskey, the product must meet the criteria of a bourbon but also be both distilled in Tennessee, of course, and filtered through charcoal before ageing. This additional step gives the whiskey a smoother and smokier taste.
Canadian whisky is often labelled as rye whisky but is not as strictly regulated as in the US and elsewhere. In fact, most Canadian “rye whiskies” are predominantly corn, whether distilled from one mash bill or through blending rye and corn whiskies. Some of these 'rye whiskies' don’t contain any rye at all.
That’s not necessarily a knock on the quality of the whisky itself. Canada produces a lot of good whiskies, however, the perceptions (and what some might call snobbery) of the whisky-drinking market incentivises distilleries to label their product as something it isn’t, enabled by loose regulation.
If you do want a genuine Canadian rye whisky, however, simply look out for 'straight Canadian rye whisky'. Whiskies labelled such must be use rye as the only grain in their mash bill and be aged for at least 3 years in 700-litre wooden barrels.
Japan is fairly new to the whisky game, having only opened its first whisky distillery in 1870 and not producing it commercially until 1924. In the past couple of decades, however, Japanese whisky has taken the world by storm.
The Japanese reverence for craft means it's perhaps not surprising that the country’s whiskies are usually based on Scotch tradition. What’s unusual about Japan compared to other whisky-producing nations is that single distilleries often produce a wide range of styles. An experimental spirit and loose regulation has birthed some of the world’s most interesting and nuanced flavour profiles, leading the more open-minded whisky connoisseurs to flock to the country in droves, all in search of something unique.