How to Differentiate Types of Whiskey: Irish, Scotch, American and Japanese.

Whiskey is whiskey, right? Wrong.

So how do you differentiate between Irish, Scotch, American and Japanese whiskeys when they’re all distilled from grain, aged in oak barrels and bottled at no less than 40% ABV (Alcohol by Volume) / 80% proof?

Simple! Read our guide to the main types of whiskey, how to tell them apart and what to expect from each. Then put it to the test.

First things first: is it whiskey or whisky? That depends on where it’s made. Whiskey if it’s the United States (mostly) or Ireland. Whisky – without an ‘e’ – if it’s Scotland or Japan.

Okay, let’s dive right in…

Irish Whiskey

Irish Whiskey

Considered by many to be whiskey’s birthplace, Ireland is also home to several different kinds of whiskey.

These are either made from barley, maize/corn or a combination of the two. Single Pot Still Irish Whiskey and Single Malt Irish Whiskey, for example, are both made from 100% barley in pot stills, while Irish Grain Whiskey is generally made from maize/corn in column stills.Irish Blended Whiskey can be a mix of single pot still, malt and grain whiskeys.

The number three plays an important part in Irish whiskey production. It must be aged for at least three years in oak barrels, and it's also traditionally triple distilled.

It’s this triple distillation that gives Irish whiskey its famed smoothness. Because the malted barley is typically dried in a coal or gas-fired kiln, rather than smoked over peat, Irish whiskey tends not to have the smokiness often associated with Scotch whisky. Combined with its smoothness, this can make Irish whiskey easier to drink.

Scotch Whisky

Scotch Whisky

Home to more distilleries than any other country, Scotland’s whiskies can be categorized by both type and region.

Single Malt Scotch Whisky, for example, which is made from 100% malted barley in pot stills at a single distillery, might also be a Speyside, Islay, Highland or Lowland Scotch, depending on where exactly it’s produced.

Though best known for its malt whisky, Scotland also produces grain whisky, made from mostly wheat or maize/corn, in column stills.

Whatever the ingredients or the region, the spirit must be aged for at least three years in oak casks and bottled at 40% ABV (80% proof) or higher.

Unlike bourbon, which must be aged in charred, new oak casks, Scotch is traditionally matured in barrels that have previously held either bourbon or sherry.

Flavor-wise, Scotch whiskies tend to be quite complex, with regional differences. Islay whisky tends to be smoky, for example, while Speysides can be fruity and Lowland Scotches sweet and light.

American Whiskey

American Whiskey

Several different kinds of whiskey are made in the US, but the main ones are bourbon, Tennessee whiskey and rye.

The biggest amongst the three is bourbon. Bourbon must be made in the US, from at least 51% corn. The rest of the mash bill is made up of other grains, like rye, wheat and barley. Water is the only additive allowed, so no coloring, caramel or flavorings.

By law, bourbon must be aged in charred, new oak barrels. To be called ‘straight’ bourbon, it must be aged for a minimum of two years.

Unlike bourbon, which can be made anywhere in America, Tennessee whiskey can only be made in Tennessee, from 51-79% corn. Before aging, Tennessee whiskey must be filtered through maple charcoal chunks using what’s known as the Lincoln County Process.

Rye whiskey, as the name suggests, swaps out the corn for rye. Made from at least 51% rye grain, it can be made anywhere in the US.

As well as being aged in charred, new oak barrels, all three kinds of whiskey must be bottled at between 80 and 160 proof.

So what do they taste like? Corn is the most sugary whiskey ingredient, so bourbon and Tennessee whiskey both tend to be quite sweet. Tennessee whiskey, with its maple charcoal filtering technique, tends to be the sweeter of the two, as well as mellower. Rye whiskey has a spicier flavor and is less sweet. All three have an element of smokiness, thanks to the charred oak barrels used for aging.

Japanese Whisky

Japanese Whisky

A relative newcomer to the world of whiskey but has risen in popularity in recent years, Japanese whisky shares a lot in common with Scotch.

It too is mostly made from malted barley in pot stills. Grain whisky, made from wheat or corn along with some barley in column stills, makes up the rest.

The big difference between Japanese whisky and Scotch whisky is that while most distilleries in Scotland specialize in producing one specific style of Scotch, Japanese distilleries often produce a variety of different styles and tastes at the same distillery.

Aged in oak barrels, Japanese whiskies also tend to be complex but they’re very well balanced too.

Key Differences

American Whiskey Irish Whiskey Scotch Whisky Japanese Whisky

it’s Made

United States

Tennessee whiskey:
State of Tennessee

Rye whiskey:
United States






Tennessee whiskey: corn

Rye whiskey:





sweet & slightly smoky

Tennessee whiskey: mellow, sweet & smoky

Rye whiskey:
spicy & smoky




Discover the differences for yourself

Got all that? Great. Now for the fun part. Why not put your newfound knowledge to the test at one of Jameson’s virtual tasting experiences?

Coming direct from our home to yours, a selection of whiskeys from the main regions, expert guidance and a little Irish craic of course are all provided.

Find out more and book your virtual tasting experience now. Finally, some homeschooling we can enjoy.

Jameson Irish Whiskey

Jameson Irish Whiskey

As you can imagine, producing a blended Irish whiskey that has been enjoyed for over two centuries, takes a lot. But don’t worry, we’ve distilled over 200 years of courage, craft and a collective appreciation for taste, into one short account. So here’s the secret behind our signature smoothness – our process and our people.