Alcohol Facts by National Draeger
Sources
Any material can serve as the basic material for alcohol as long as it contains 12-15% sugar. Such materials might be fruit juices, malt or cereal grain extract, vegetable pulp (potato, cactus), and molasses.
Fermentation
Fermentation is the process by which all drinking alcohols are produced. Yeast from the air, or added as a pure culture, produces alcohol and carbon dioxide by fermenting the sugars in fruit juice, cereal grain mash, or other raw material. Maximum alcohol content of a fermented beverage is 14-15% by volume; higher alcohol contents are produced by a further process of distillation.
Distillation
Whisky, gin, rum, brandy, etc., attain high alcohol contents through the process of distillation. Alcohol boils at 78.3 C (173 F) and water at 100 C (212 F). When a mixture of alcohol and water is heated, the alcohol boils at a lower temperature. The resultant steam is caught and cooled. By repeating the process, nearly pure ethanol can be obtained.
Types of beverages
The sources, method of production and approximate alcoholic content of various beverages are shown in Exhibit C-1.
Congeners
In addition to alcohol and water, alcoholic beverages contain numerous compounds or impurities known as congeners. These typically impart a characteristic flavor and odor to the beverage. They constitute a very small proportion of the total volume of the beverage. There is no evidence that congeners contribute in any discernible degree to the depressant effect of alcoholic beverages.
Proof system
In the United States, the proof of an alcoholic beverage is twice the percentage of alcohol by volume. Thus, an 86-proof bottle of whiskey contains 43% of alcohol by volume. Most alcoholic beverages have a maximum of approximately 50% alcohol by volume; the remainder consists of water and flavoring agents (cogeners). For example, beer has a relatively low alcoholic content and is approximately 90% water.
