Scotch whisky’s family tree spans thousands of years. It’s hard to pinpoint how the secret of distillation made its way to Scotland – the Phoenicians, Celts and Irish monks all were partly responsible. All we can be sure of is that the documented reference to “eight bolls of malt wherewith to make aqua vitae”, recorded in transactions of the court of James IV, dates back to 1494. The Latin term “aqua vitae” (water of life) and aqua fortis (strong water) go back even earlier, to the 12th century. Translation into Scots Gaelic gave us the term uisge beatha (“ooska bah”), meaning “water of life”. During the 1500s, the pronunciation of “ooska” morphed into “ooski”, and eventually to “whisky”.
Some explanations of “Scotch”, “whiskey”, and “whisky” are a good place to start for this primer. “Whiskey” is a generic term for a distilled spirit made from grain. These grains are usually corn, wheat, rye, or barley. Depending on which grain is used, and in what country the whiskey is distilled and aged, it has different names and spellings. Scotch whisky can be made from any type of cereal. Scotch single malts are made from only malted barley. Scotch whiskies must be distilled and aged in Scotland, and the spelling (protected by law) is without the ‘e’, as it is in other countries such as Japan and Canada.
Why is it called single malt?
“Single” means the liquid in the bottle is the product of a single distillery. Every drop came from just one distillery – the one listed on the label. Single malt is one of the two main classifications of Scotch. If a Scotch whisky is not a single malt, it could be a ‘blended Scotch’, meaning a blend of single malts and grain whisky. There are other classifications, as defined by the Scotch Whisky Association.
Malt or ‘malting’ is the name given to the specific process used to trigger the conversion of starch into fermentable sugars. Traditional malting methods dictate that barley be harvested, soaked in water for a few days, drained and spread over a large floor to germinate. The germination process is stopped by the introduction of heat, as the grain is dried in a large kiln. At this stage, the malt can be ‘peated’ by burning a peat fire underneath the perforated floor of the kiln. Not all malts are peated. In the early part of the 20th century, the malting process would be done ‘in-house’ by distilleries; today, the bulk of distilleries use malt produced in large commercial ‘drum’ maltings, to their own specifications.
What is peat, and how does it make some Scotch smoky?
(Note: please see For Peat’s Sake – In Scotch Whisky and Beyond for a more complete description of peat.) Peat is an organic material, comprised of decomposed and compressed mosses, leaves, roots, and branches, found in marshy bogs. The peat is dug from the bogs and dried. Smokiness is determined by how much peat “reek” (smoke) is infused into the barley as it dries. Whether lightly smoked, heavily smoked, or not smoked at all, the barley is ground into grist, then goes on to other steps in the process of making the whisky.
Mashing, Fermentation, Distilling, and Maturation
Once the malted grain is dried, it is ground into a rough flour known as ‘grist’. Grist is mixed with hot water – the vital element used to trigger the now-ready enzymes to convert the starches present into fermentable sugars. The mashing process is completed by drawing off the sugary liquid that comes from flushing hot water through the grist, known as wort. Distillers can manipulate their wort at this stage if they want to produce a spirit with a particularly malt-driven flavor. Yeast is added to the wort and fermentation begins as the sugars are consumed by the yeast and converted into alcohol, in the space of 48 hours, giving a liquid of 7-10% abv called ‘wash’.
Most Scotch malt whisky is double distilled. Distillation takes place in copper stills that can vary widely in shape, size and volume and play a vital role in determining the character of a spirit. In very simple terms, the longer the alcoholic vapor is in contact with walls of copper, the lighter the spirit will be.
As the final part of the production process, the distilled spirit that will become Scotch whisky goes into the cask for maturation, or aging. At this point, it is completely clear. Colors from pale yellows, through rich ambers to deep golds develop over years, due to the interaction between the wood of the cask and the liquid. Traditionally, two types of wooden casks are used to age Scotch. American white oak (Quercus alba) casks, previously used to age American whiskies, make up the majority of the “barrel recipe”. Casks previously used to age sherry, made from European oak (Quercus robur), are the second component of the barrel recipe. Some single malts are aged only in American oak, and some only in European oak, but most single malts are comprised of liquid aged in both woods. By law, a spirit can only be called Scotch whisky once it has spent three years maturing in cask, in Scotland. During maturation, while the casks breathe in the local atmosphere, whisky vapors are lost by evaporation. This earthly loss is called “the angels’ share”. The local atmosphere contributes greatly to the aroma and flavor characteristics of each whisky. Regionality becomes important in classifying these characteristics, with the primary regions including Highlands, Lowlands, Speyside, and Islay, pronounced “eye luh”.
- There is actually more water in single malt whisky than there is alcohol. By law single malts must be bottled at a minimum of 40% ABV (alcohol by volume), leaving about 60% as water.
- A glen is a valley, usually associated with a river. Many distilleries were originally built in glens to take advantage of the water supply. Some well-known distilleries are located in the glen of the rivers Livet, Fiddich, and Deveron. Not all glens are associated with rivers. Glenmorangie, for instance, has two Gaelic roots: “glen of tranquility” and “glen of the big meadows”, and Glen Garioch’s Gaelic translation refers to “glen of the rough ground”, and is a rich barley growing region.