Wine and Spirits : Singular Sensation: Just What Is All-Malt Scotch?
Single-malt Scotch is whisky made entirely of the distillate of barley malt. It differs from blended Scotch, which can be as much as 80% neutral spirits made from cereal grains such as corn or wheat.
In Scotland, the location of the distillery, the selection of the barley, and the process of making single-malt (or all-malt) give each Scotch its unique character.
Barley is harvested each fall (about the same time wine grapes are harvested) and soaked in water until germination begins. Laid out to dry and germinate, the barley starch turns into sugar. The germination then is stopped in a kiln. Most producers use kilns fueled by burning peat. This peat/smoke aroma is imparted to Scotch in varying amounts, depending on the amount of peat used.
A mash is then made by adding local water to ground malt. The resulting wort (pronounced “wert”) is then fermented, producing a beer-like liquid called a wash. This is then placed in a small copper pot still and distilled twice. The first and last portions of each distillation are removed so only the “heart” of the distillation is used.
Copper pot distillation is slow, usually taking more than four days for a batch (compared to 1 1/2 to 2 hours for far more rapid continuous still distillation used in cheaper drinks).
The final distillate is clear and is about 70% alcohol. It is usually cut to about 60% with local water (which adds more local distinctiveness), and then is aged in American oak barrels for a period of years to mature. Some distilleries, notably The Macallan, age their Scotch in Sherry casks to gain a nuttier character.
Aging is conducted for nearly a decade for most quality single-malt, 15 to 18 years for “super-premiums” and even longer in some special cases.
A blender, officially called a “nose,” assembles the various casks of Scotch into a final product that fits the house and regional style.
Single-malt Scotch is as much an acquired taste as is Cognac, with which it is often compared. And, just as Cognac is brandy from a specific region and usually more assertive in character than plain brandy, so is single-malt Scotch from a specific region more assertive in flavor than its generic counterpart, blended Scotch.
There are four major--and quite different--regions of Scotland where Scotch is made, with sub-regions claiming their own distinct character. Highland Scotch tends to be flowery and fragrant; Lowland Scotch is delicate, soft and almost sweet; Campbeltown is hearty and rich; Islay (the s is silent; it’s pronounced “I lay”) is peaty and has an assertive earthy character.
Incidentally, the makers of Scotch use the spelling whisky ; when spelled whiskey , the word refers generically to other grain spirits such as rye, bourbon and Irish.