This quick overview will help you navigate through the wide array of whiskies worldwide. There are differences between the core ingredients, production methods and ageing requirements, which all contribute to their unique flavours.
You may have noticed that there are two spellings for whisky. Whiskey is preferred by Irish and Americans, whisky is used in Scotland, Canada, Japan and the rest of the world. Like always, there are a few exceptions to the rule (see Waterford Distillery for example).
Scotch Whisky
Scotch whisky is made with three ingredients: water, yeast and cereals, and there are five stages in the production process: malting, mashing, fermentation, distillation and maturation.
To be called scotch, the spirit must be distilled and matured in Scotland for at least three years and bottled at a minimum 40% ABV.
Scotch whisky can only be matured or finished in new oak casks or oak casks which were previously used to mature wine, beer, ale or spirits. However, this is not allowed if those casks were previously used to mature wine, beer, ale or spirit produced from, or made with, stone fruits, or if any flavouring (including fruit) or sweetening has been added after fermentation.
Also, any previous maturation must have been part of the traditional process for the alcoholic drink concerned. For example, ex-gin casks would not work, as ageing is not part of the traditional gin-making process.

There are five categories under scotch whisky:
Single Malt Scotch Whisky – Distilled at a single distillery from water, yeast and malted barley. It is made according to a traditional batch process using copper pot stills.
Single Grain Scotch Whisky – Distilled at a single distillery from other grains (such as wheat or corn) with or without malted barley. Single grain whisky is mainly used for blends, however there are a growing number of new releases by independent bottlers. The spirit usually goes through a continuous distillation process (also known as patent still distillation), although Arbikie Highland Rye, for example, is distilled using copper pot stills.
Blended Scotch Whisky – A blend of one or more Single Malt Scotch Whiskies and one or more Single Grain Whiskies. This category is the most sold around the world, making up over 90% of the scotch whisky sales worldwide.
Blended Grain Scotch Whisky – A blend of Single Grain Scotch Whiskies from different distilleries. Distilled using the continuous distillation process.
Blended Malt Scotch Whisky – A blend of Single Malt Scotch Whiskies from more than one distillery.
Scotch whisky has a wide array of flavour profiles, from savoury to very sherried to peated expressions. Peat is probably the most well-known difference when it comes to whiskies around the world, although that is not to say that peat is limited to Scotland. Single grain scotch tends to be sweeter with a creamier mouthfeel compared to single malts. Due to these dessert-like tasting notes, single grain whisky is closer to bourbon in taste.

Irish Whiskey
Irish Whiskey must be produced and aged in Ireland. Most Irish whiskey is triple distilled, but this is not a rule. All whiskey must be left to mature for a minimum of three years. There aren’t any rules when it comes to the cask type, which allows plenty of experimenting with various wood types and seasoning. Also, new casks can be used. Irish Whiskey is often slightly sweeter and smoother than scotch but not the same way as bourbon, and the flavour obviously varies based on the type of whiskey. Unmalted barley contributes to a spicier flavour profile.
In Ireland, whiskey must be described as Irish Whiskey, Uisce Beatha Eireannach or Irish Whisky.
There are a few types of Irish Whiskey:
Single Malt is produced from malted barley and is usually triple distilled in copper pot stills.
Single Pot Still Whiskey is made with a combination of malted and (raw) unmalted barley and is triple distilled in a pot still. This unique style used to be known as pure pot still.
Grain Whiskey is made from a variety of grains: malted barley, corn, wheat or unmalted barley. This style is distilled using continuous distillation and is mainly used to make blended whiskey.
Blended Whiskey is a combination of Grain Whiskey (column or Coffey still) and Single Malt Whiskey and/or Single Pot Still Whiskey. It is the most popular style in Irish whiskey production.

American Whiskey
American Whiskey has a wide range of styles, including rye, bourbon, rye malt, malt, wheat, Tennessee and corn whiskey. As I’m not an expert on American whiskey (yet!), I will only focus on three of the most popular categories: Bourbon, Rye and Tennessee Whiskey.
Bourbon can be made anywhere in the US, although it is often associated with Kentucky. Bourbon is made with a minimum of 51% corn (often up to 70%) and with a combination of grains such as malted barley, wheat or rye. The production process often includes sour mashing where stillage (residue) from previous distillation is added into the new mash.
Bourbon must be aged in newly charred American oak barrels. If the bourbon is aged for a minimum of two years, it can be called Straight Bourbon. No additives or colourings can be used to make Straight Bourbon. Straight bourbon, or any other straight whiskey, can be made of mixture of straight whiskeys from the same state. If spirits from other states are used, the whiskey must be labelled as blended.
Bourbon is sweeter and nuttier than most whiskies with notes of vanilla, caramel and oak spice.
Rye Whiskey is made using at least 51% rye and the rest is either malted barley or corn. There are distilleries that use a mash bill that can peak at 90% rye. If produced in the US, the rye must be aged in newly charred American oak barrels for a minimum of two years. Rye Whiskey tends to have a spicier, more peppery flavour profile compared to other American whiskies.
Tennessee Whiskey is not to be confused with bourbon even though it is basically a sub-category of it. As the name indicates, this style of whiskey can only be produced in Tennessee. A special charcoal-filtering method is used to give the whiskey its unique flavour profile. This is known as the Lincoln County Process.
The spirit must be aged for a minimum of two years in new charred oak barrels. The flavour profile is similar to bourbon, but perhaps slightly lighter and less sweet. The charcoal takes away some of that harshness, making the whiskey more refined. Expect notes of cinnamon, vanilla, banana and nuttiness.
Jack Daniel’s is probably the most well-known Tennessee whiskey brand.

Japanese Whisky
Until recently, anything could be labelled as Japanese Whisky as long as it was bottled in Japan. It is not uncommon for blended Japanese whisky to contain whiskies from other countries, such as Scotland or Canada (Nikka from the Barrel and Nikka Days, for example).
Recently, The Japan Spirits & Liqueurs Makers Association announced new stricter Japanese Whisky regulations. These aren’t legally binding but are still a step in the right direction.
The new regulations are as below (taken from a Forbes article):
- The only raw ingredients allowed for use in production are malted grains, other cereal grains, and water extracted in Japan. Malted grains must always be used.
- Fermentation, distillation, and saccharification must take place in a distillery located in Japan, with the alcohol volume of the distillate not allowed to go above 95% in strength.
- Wood casks with a maximum capacity of 700 litres must be used for the maturation of the distilled product and must be matured in Japan for a minimum of 3 years.
- Bottling has to take place in Japan, and the whisky has to have a minimum ABV of 40%.
- Plain caramel colouring (E150) is allowed to be added.
Many whisky producers are likely to change their labelling to match the new regulations rather than change their production methods.
Japanese Whiskies tend to have more delicate, fragrant and floral flavour profiles compared to scotch whisky. A lot of this is due to different cask finishes. Distilleries can also have their own strain of yeast, which has an impact on the fermentation.

Indian Whisky
Most of the Indian whisky sold outside the EU is a blend of spirit made from molasses (similar to rum) and either grain whisky or pre-blended scotch whisky. There aren’t many regulations when it comes to Indian whisky; however, there are some exceptional Indian Single Malts that should not be dissed. These are produced in a similar way to scotch whisky. It must be distilled at a single distillery from water, yeast and malted barley and matured for a minimum of three years in oak casks.
Indian single malt whiskies are known for their fruity, malty and spiced character.
Amrut was the first to produce Indian single malt whisky.
Indian single malts and blended malts can be made using solely Indian barley or with a small amount of peated Scottish barley.
Due to the hotter climate, maturation is much faster in India. The angel’s share is also higher at 11–12%, compared to 2% in Scotland. This means most Indian Whiskies are only aged for a few years and are often labelled without an age statement. As India has many microclimates, it could be hard to regulate the ageing process.

Canadian Whisky
Canadian Whisky is often known as ‘rye’, yet there isn’t any specific requirement as to how much rye should be used, and the whisky often contains a higher percentage of corn. Most Canadian whisky is made using a column still.
Canadian whisky must be aged for a minimum of three years, but there are no rules when it comes to the barrel types, although they shouldn’t be larger than 700 litres. The whisky can contain caramel and other flavourings. Canadian whisky has a slightly spicier flavour profile compared to bourbon.

Overall
Not all whisky production is fully regulated, and it is difficult to compare the rules around the world. The production methods tend to be very similar, but the location and the core ingredients used all contribute to the flavour profile.
American and Canadian whiskies range from sweeter, more honeyed to Christmas spices and peppery notes based on the balance of the mash bill. Now that Scotland has also started to produce rye whisky again (theirs goes under single grain whisky) the whole category is evolving even more.
In both India and Japan, the single malt category is growing, with better quality whiskies, and even if the regulations aren’t legally binding or are completely missing, these distillers want to produce a top-quality product that can rise to the same level as their Scottish counterparts.
What types of whisky do you like? Have you tried Indian Single Malts yet?
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