Figuring out the difference between a Scotch whisky and Irish whiskey takes some time and effort. The two spirits share major similarities, but also diverge in a few crucial ways. These differences amount to more than whether you spell one with an “e” or not, though it’s worth clarifying — Scotch whisky is always spelled without the “e”; Irish whiskey is always spelled with the “e.” This quirk seems to have started in the late 19th century, created by Irish distillers as a way to distinguish Irish whiskey from Scotch whisky on the consumer market.
Names aside, there’s more that separates the two spirts than simply the regions these whiskeys are produced in. Yes, Ireland and Scotland are close neighbors on the Irish Sea but their spirits tend to have only minor similarities past both being brown booze made from fermented and then distilled grains. Hopefully, the explainer below can help you better understand the difference between these two powerhouse regional spirits. The first thing to remember with booze is that sometimes there aren’t any hard and fast rules. Or, more specifically, rules exist but so do exceptions, nuances, and thriving rule-breakers.
In the end, what may be true “traditionally” may no longer be true for some distillers working today. Exceptions abound. Still with us? Cool, let’s dive in!
What Is Scotch Whisky?
Scotch whisky can come in three forms, generally — single malt, single grain, and blended scotch. Overall, those whiskies come from six regions around Scotland: The Highlands, The Islands (sometimes grouped with The Highlands), Islay, Campbeltown, Speyside, and The Lowlands.
Single malt scotch is a distillate made in one distillery with a single malted barley mash bill (recipe) in pot stills. A single grain scotch is often used to denote a whisky made with a single grain that’s not malted barley. However, in Scotland, malted barley is added to start the fermentation process. A single grain whisky is mostly used for blended whisky. So, the use of “single” in this case, then, refers to the fact that booze was made at a single distillery.
Blended scotch makes up for 90 percent of the Scottish whisky market. So it’s probably what most people will be familiar with or start with as an entry point to the style. This is simply a blend of malt whisky and grain whisky wherein a master blender marries two or more barrels of booze into one delicious elixir.
From there, the concept of how the whisky is made is very similar to most other whisk(e)ys around the world. Malted cereals or grains (in this case almost always barley malted with peat smoke) is ground to a grist, before water and yeast are added to begin fermentation. That fermented water — not unlike a beer — is distilled twice. Finally, the distillate is transferred to barrels (sometimes ex-bourbon barrels from America, sometimes not) to rest for at least three years. That’s pretty much it.
Each region of the six regions of Scotland that produce whisky has their particular nuances and uniqueness. Resting barrels along the briny, cold Scottish coastline can add touches that barrels up in the mountains or forests will not get. But, at the end of the day, we’re talking some very minor variables here. You can get umami smoke monsters from the coast or the forest, depending on what the head distiller is attempting to represent with the malt, water, and barrels.
What Is Irish Whiskey?
Irish whiskey is a different beast. First, there aren’t region specific Irish whiskeys per se. There’s a clear distinction between Northern Irish whiskey like Bushmills and Republic of Ireland whiskeys like, say, Jameson. But, really, there’s not Highland or Islay-like designations in play here.
What is in play are the single monikers. Irish whiskey comes in single malt, single pot still, single grain, and blended forms. Three of those four we already know. Where Ireland swerves is with the “single pot still” category. A single pot still whiskey uses both malted barley and unmalted or raw barley in the mash bill. That’s a huge freakin’ difference. Think about it this way, there’s a massive difference between a baked apple and a raw apple, right? So, yes, this helps Irish whiskey differentiate itself through flavors right out of the gate.
That’s not to say there aren’t Irish whiskeys with peated smoked malts. There are. Connemara famously uses peated malts and has a nice smoky presence. But that’s more the outlier than the standard when it comes to Irish expressions.
Another big distinction is that Irish whiskey is triple distilled, mostly. Back in the 1800s, Irish distillers were ruling the whiskey world and wanted to assure that Irish whiskey was always better than their neighbor’s scotch. Triple distillation became a hallmark of the island. Today, not all Irish whiskeys are triple distilled but most single malts and single pot still expressions will be. Another ripple in Ireland is with the grain whiskeys. Often those expressions are distilled in a column still, or Coffey still and not a pot still.
From there, we have a similar process of malts to grist to fermentation to distillation to barreling. In most cases, Irish whiskeys will be aged in ex-bourbon barrels and ex-sherry casks and then blended into a single expression for bottling. That’s not a universal truth, of course, and new barreling processes are coming into play, most famously with big brands like Jameson barreling in stout or ale casks.
Putting aside blends and grains, single malt scotch and single pot still Irish whiskey are two very different beasts. One is made exclusively with malted barley that’s almost always malted using local peat in the kilning process. The other literally uses a raw version of that ingredient. So, you’re going to get a very different experience between those two styles.
We’re not — in any way — saying one is more superior, refined, or correct. Scotch and Irish whiskey are the results of literal centuries of tinkering, fine-tuning, and the slow refinement of practices, recipes, and ideas. A single malt scotch can be a lot of things within Scotland alone and, again, depending on what the head distiller is aiming for. The same goes for Irish whiskey. In the broadest of broad terms, scotch is going to have a smoky edge (not universally though) that’s often not found in mainstream Irish whiskey. But, again, there are always exceptions on either side of the Irish Sea.
Our advice, try one of each, then try some more. Find what you dig and dive deeper. At the very least, you’ll get a nice buzz on along the way.