Base spirit — Grain
Whiskey
Also spelled: whisky
A grain spirit aged in oak barrels and produced across the world in radically different styles. From the peated single malts of Islay to the sweet vanilla warmth of Kentucky bourbon — whiskey is one of the most diverse and rewarding spirit categories to explore.
What is whiskey?
A note on spelling: “Whiskey” (with an e) is used in Ireland and the United States. “Whisky” (without the e) is used in Scotland, Canada, Japan, and most other producing countries. Both are correct — just for different origins. We use “whiskey” throughout this site.
Whiskey is a distilled spirit made from a fermented mash of grains — malted barley, corn, rye, wheat, or a combination — and aged in oak barrels. The grain, the production method, and the length of ageing all shape the final flavour, which is why Scotch single malt and American bourbon can taste so completely different despite both being whiskey.
It’s produced in dozens of countries but the styles that matter most for cocktails and general drinking come from a handful of key regions: Scotland, Ireland, the United States, Canada, and Japan. Each has its own legal framework, grain traditions, and flavour identity — and each is worth exploring on its own terms.
Flavour profile
Whiskey’s flavour range is broader than any other spirit category. The notes below are the most common across styles — but individual bottles can land anywhere from delicate floral to intensely smoky.
The main whiskey styles
Each style is shaped by its region, legal requirements, grain bill, and production traditions. This is an overview — each deserves its own deep dive.
Scotch Whisky
Scotland
Must be aged a minimum of 3 years in oak in Scotland. The five regions — Highlands, Lowlands, Speyside, Islay, and Campbeltown — each have distinct characters. Speyside tends toward fruit and honey; Islay is famous for heavy peat and smoke. Single malt (one distillery, malted barley) and blended Scotch are the two main categories.
e.g. Glenfiddich, Laphroaig, Johnnie WalkerBourbon
United States (Kentucky)
Must be made from at least 51% corn, aged in new charred American oak barrels, and produced in the USA. No minimum ageing requirement, though “straight” bourbon must be aged at least 2 years. Sweeter and fuller-bodied than Scotch, with strong vanilla, caramel, and often coconut notes from the new oak.
e.g. Maker’s Mark, Buffalo Trace, Woodford ReserveIrish Whiskey
Ireland
Must be aged at least 3 years in wooden casks in Ireland. Typically triple-distilled, which gives Irish whiskey its famously smooth, light character. Rarely peated. Styles include single malt, single pot still (using unmalted barley — uniquely Irish), grain, and blended.
e.g. Jameson, Redbreast, Green SpotAmerican Rye
United States
Must contain at least 51% rye in the mash bill. Spicier and drier than bourbon, with pepper, caraway, and herbal notes. The spirit of choice for classic cocktails like the Manhattan and Old Fashioned before bourbon took over. Currently undergoing a major revival.
e.g. Rittenhouse, Sazerac Rye, WhistlePigJapanese Whisky
Japan
Inspired by Scotch traditions but developed into its own distinctive style — precise, balanced, and delicate. Often blended from a wide range of cask types and grain profiles within a single distillery. No minimum ageing requirement in Japanese law, which has led to some controversy around age statements.
e.g. Suntory Toki, Nikka From The BarrelCanadian Whisky
Canada
Must be aged at least 3 years in Canada. Typically lighter and smoother than American whiskeys, often blended from multiple grain distillates including a high-rye component for spice. Sometimes called “rye” in Canada even when not primarily rye-based. An underrated category worth exploring.
e.g. Crown Royal, Canadian Club, Lot No. 40Tennessee Whiskey
United States (Tennessee)
Produced like bourbon but with an additional step — the Lincoln County Process — where the spirit is filtered through sugar maple charcoal before ageing. This mellows the spirit and gives it a distinctive smoothness. Jack Daniel’s and George Dickel are the two major producers.
e.g. Jack Daniel’s, George DickelSingle Malt Scotch
Scotland — specific regions
Made at a single distillery using 100% malted barley and pot stills. The most celebrated and collected style of whiskey in the world. Flavour varies enormously by distillery, cask type, and age. Worth exploring slowly — this is a style that rewards patience.
e.g. Macallan, Ardbeg, DalmoreHow whiskey is made
The core process is similar across styles, though every region and distillery introduces variations that shape the final character significantly.
Malting & mashing
Grain is prepared — barley is malted (germinated and dried) to develop enzymes that convert starches to sugar. It’s then mashed with hot water to extract those sugars, creating a sweet liquid called wort. For bourbon and rye, the grain bill is cooked and mixed without the same malting process.
Fermentation
Yeast is added to ferment the wort into a low-alcohol wash, similar to beer. Fermentation time and yeast strain both affect flavour — longer fermentation tends to produce more fruity, complex character.
Distillation
Scotch single malts use copper pot stills, distilled twice (or three times for some Irish expressions). Bourbon and grain Scotch use column stills for efficiency and consistency. The type of still has a major impact on how much flavour character carries through to the final spirit.
Ageing
All whiskey must be aged in oak. Bourbon uses new charred American oak barrels, which gives it those strong vanilla and caramel notes. Scotch and Irish whiskey typically use ex-bourbon, ex-sherry, or other previously used casks. The interaction between spirit and wood is where most of whiskey’s flavour develops.
Blending & bottling
Single malts are bottled from one distillery’s casks. Blended whiskeys combine malt and grain distillates from multiple sources for consistency and volume. Both approaches produce excellent whiskey — the blended vs single malt snobbery is largely unwarranted.
ABV across styles
Most whiskeys are bottled between 40–46% ABV, but cask strength expressions can go considerably higher. Here’s the typical range by style.
Key grains & what they bring
The grain bill is one of the most important flavour variables in whiskey. Here’s what each major grain contributes.
Quick facts
Legal minimums: Requirements vary significantly by country. Scotch must be aged 3 years minimum in Scotland. Bourbon has no minimum age (though “straight” bourbon requires 2 years). Irish whiskey must be aged 3 years. Most require a minimum of 40% ABV.
Why new vs used barrels matter: Bourbon must use new charred oak, which imparts strong vanilla, caramel, and char flavours quickly. Scotch and Irish use previously filled casks, which gives a gentler, more integrated wood influence — and also means bourbon producers are major barrel suppliers to the Scotch industry.
Emerging regions: India (Amrut), Taiwan (Kavalan), Australia, and English distilleries are all producing genuinely exciting whiskeys that challenge the traditional hierarchy. Worth seeking out.
Water or ice? A small drop of water can genuinely open up the aroma of a cask strength or high-ABV whiskey by breaking up the alcohol bonds. Ice numbs the flavour — a large single cube is fine for long drinks but avoid heavily icing something you’ve paid serious money for.
Substitutes in cocktails: Bourbon and rye are often interchangeable in cocktails — rye gives more spice and dryness, bourbon more sweetness. Irish whiskey works well where you want a lighter touch. Scotch is trickier to substitute because the smoke can be divisive.
Cocktails that use whiskey
Whiskey is the base for some of the oldest and most enduring cocktails ever created. Here are the essential ones.
Recommended bottles
One reliable entry point across each of the main styles — all widely available in the UK.
Glenfiddich 12
Scotch Single Malt · 40%
The world’s bestselling single malt for good reason. Fresh pear, light oak, and gentle vanilla. A reliable, crowd-pleasing introduction to Speyside Scotch.
Buffalo Trace
Bourbon · Kentucky · 40%
Outstanding value. Smooth and well-balanced with vanilla, toffee, and a touch of spice. Works equally well in cocktails and sipped neat.
Redbreast 12
Irish Single Pot Still · 40%
One of the best Irish whiskeys made. Rich and fruity with a distinctive oily texture from the unmalted barley. Sherry cask influence adds dried fruit and spice.
Rittenhouse Rye
American Rye · 50%
The bartender’s rye of choice. Bold, spicy, and rich — genuinely transforms a Manhattan or Old Fashioned. Bottled in Bond at 50% ABV.
Suntory Toki
Japanese Blended · 43%
Light, floral, and exceptionally smooth. Designed as a highball whisky and brilliant served long with soda water. A great entry point into Japanese whisky.
Laphroaig 10
Islay Scotch Single Malt · 40%
The definitive peated Scotch. Intensely smoky, medicinal, and briny — not for the faint-hearted, but those who love it, love it completely.
Storage & shelf life
Whiskey is one of the most robust spirits to store — once bottled, it stops ageing and will keep well for years under the right conditions.
Temperature
Room temperature is ideal — around 15–20°C. Avoid storing near heat sources like radiators, which can accelerate evaporation.
Light
Keep away from direct sunlight. UV can degrade the colour compounds and subtler flavour notes over time, particularly in lighter styles.
Position
Store upright — unlike wine, whiskey should not be stored on its side. Prolonged contact with the cork can deteriorate it and introduce off-flavours.
Shelf life
Indefinitely if sealed. Once open, the spirit is stable for years though the top quarter of a bottle will oxidise more noticeably. Finish bottles within 1–2 years of opening for best flavour.