Liquor is an alcoholic beverage distilled from the fermented juices of various kinds of fruits and grains. The term sometimes refers to fermented beverages, such as beer and wine. However, only stronger beverages distilled from fermented liquids are considered to be liquors. The strength of liquor is measured by its alcoholic content, or proof. A 100-proof liquor, for example, has an alcoholic content of 50 percent by volume. Liquors are also classified according to how sweet they are. The term "dry" is used to describe liquors that are not sweet.
Spirits and Distilling
Liquors, in common with all other alcoholic beverages, are produced basically by alcoholic fermentation (the decomposition of sugars into ethyl alcohol by yeasts) of sugar-rich liquids.
The diversity of liquors and related alcoholic beverages is a reflection of the widely differing sources of fermentable sugar. This sugar is directly available in some raw materials (such as grapes and molasses), but in other raw materials (cereals, potatoes) starch must be converted into fermentable sugars by adding enzymes (biological catalysts).
The traditional source of such enzymes is barley malt and the process of conversion is known as "mashing."
Distillation and Maturation
Yeast fermentation leads to a maximum alcoholic content of about fifteen percent in beverages such as wine. But in the production of liquors, fermentation is followed by distillation, which concentrates alcohol in the distilled spi1it. Distillation is the heating of alcohol-containing liquids, so that the alcohol boils off to be condensed, collected, and added as desired to increase strength. The degree of concentration and distillation of volatile flavoring substances or "congenerics" depends on the type of still and the way it is operated.
Simple " pot" stills distill alcohol at lower concentration to give a liquor with a characteristic flavor , whereas "continuous column" stills are more efficient, yielding liquors of higher alcohol concentration but which have very little or even no congeneric flavor.
Newly distilled liquor is seldom suitable for immediate consumption. It is often stored in wooden casks for a number of years to achieve a mellow and developed flavor such as that of whiskey or brandy. The quality of liquors is frequently related to the period of storage in wooden casks.
For bottling, liquors are normally reduced with pure water to an alcohol content of about 40 percent by volume.
Malt and Grain Whiskeys
Scotch malt whiskey is made entirely from a mash of malted barley. The fermented mash produced in a mash tun is first distilled into what are known as " low wines" in a mash still, and the low wines are redistilled in a similar pot still, the spirit still. In the second distillation "heads and tails" fractions (the first and last parts obtained in the distillation) are returned to the low wines . The middle fraction is the new whiskey. Malt whiskey is aged in reusable oak casks for eight, twelve, or more years before being sold as single malt whiskey the product of an individual distillery.
Malt whiskey is blended with Scotch grain whiskey to produce blended Scotch whiskey. Grain whiskey is made from a mash of pre-cooked maize and a proportion of barley malt. The wash is distilled in a semi continuous, two-column still. Scotch grain and malt whiskies are aged separately and blended shortly before bottling. Irish whiskey is made from unmalted cereals, including barley, wheat, and rye, which are mashed together with malted barley.
Bourbon whiskey, named after Bourbon county, Kentucky, where it was first made, comes from a grain mash of at least 51 percent corn. The distillate is generally matured for four years in new oak casks that are charred internally before filling. Kentucky is still the center of the bourbon industry.
Canadian whiskey is a blend of a strongly flavored rye whiskey and a lighter cornbased whiskey. Blended whiskies are made by adding neutral spirits to the straight whiskey.
Brandy is the distillate of wine. Cognac, the best known brandy, is made from the wine of the Charente (a region in southwest France) by two successive distillations in characteristic pot stills. Cognac is matured in Limousin oak casks and the finer qualities age for ten , twenty, or even more years.
The quality of Cognac depends on the soil and conditions of the particular vineyard from which the wine is produced around the town of Cognac.
Armagnac, singly-distilled in a more efficient pot still, is made near Agen in southwestern France.
Rum is the distillate of fermented molasses, the mother liquor of crystallized cane sugar. Flavored rums, dark in color, are traditionally made by pot- still distillation and aged in wood, but most white rums are distilled to a light flavor, which is modified by an additional treatment with charcoal. Other liquors are made from local sources of fermentable materials: arrack from palm juice, rice, or molasses; calvados and applejack from apples: kirschwasser from chenies; tequila from the Mexican agave or century plant. Vodka is a liquor that has no flavor apart from that of ethyl alcohol. Liquors such as gin, ouzo, and liqueurs derive their flavor from added ingredients and are not, in general, from the cogenerics of the original spirit. They, like vodka, are made from a base liquor of relatively neutral and flavorless character, produced from avatiety of materials, including grain, molasses, and potatoes. Gin is flavored by juniper berries and spices.
Ouzo is made by flavoring a base spirit with aniseed. Aquavit is a base liquor flavored with caraway. Liqueurs are liquors sweetened by the addition of sugar. Gin, vodka, and liqueurs do not generally require aging.