A single malt alcohol, such as single malt whiskey or scotch, is a type of liquor that has been made at one "single" distillery, out of a single primary malting ingredient. Like vintage wines, single malts are unique to their maker and can display a wide range of flavor characteristics depending on the region, process, and ingredients. Although single malts are believed to hail originally from Scotland, they are now made throughout the world, gaining popularity in many countries including Ireland, Japan, and New Zealand.
The creation of malted beverages begins with a germination process. Water is added to a grain, heated, and allowed to sit for several days, allowing the grain to produce enzymes necessary for fermentation. Almost all single malts use barley as their malting ingredient, although other grains, such as rye, can be used as well.
After the malting process is complete, the grain is mashed and mixed with more hot water, which breaks the grain down into sugars that will ferment. The fermentation process of a single malt beverage is at least three years, but many top-end varieties are stored in oak casks for much longer.
Single malts are unique in that they are produced by one distillery only. If a bottled malted beverage uses grains from other sources or blends two or more single malts from separate distilleries, it is called vatted, double, or blended. This allows distilleries to create characteristic beverages with their own unique flavor palate and preferences. Many connoisseurs of single malts are fans of specific distilleries or regions, much as a wine drinker prefers specific wineries or appellations.
Because of the high amount of sugar created in the fermentation process, single malts typically have a very high alcohol content. Though the amount varies based on vintage and age, most single malts contain 40-60% alcohol. Considering that wine and beer range between 7-18% alcohol and other liquors, such as vodka, usually reach about 35-50%, single malts may seem to contain an excessive amount of alcohol for casual drinkers. However, single malts are typically served without any added ingredients in very small quantities, and are usually meant to be slowly sipped rather than chugged down.
If you are interested in trying single malts, several websites and books exist that offer guides to this realm of spirits. Prices for this highly-sought after variety of beverage can be quite high, but vary extensively depending on age and distillery. For a 12-year aged single malt whiskey, expect to pay between $20-$40 US Dollars (USD). Usually, the older a single malt gets, the higher the price. Some 40 or 50 year old varieties can cost thousands of dollars, making finding and drinking one a rare experience.