Where Do Alcoholic Beverages Come From?

The alcohol that you can drink, called ethyl alcohol or ethanol, is produced by fermenting carbohydrates, such as sugars and starches. Fermentation is an anaerobic process used by yeast to convert sugars into energy. Ethanol and carbon dioxide are waste products of the reaction. The reaction for the fermentation of glucose to produce ethanol and carbon dioxide is:

C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂

The fermented product (e.g., wine) can be used, or it can be distilled to concentrate and purify the alcohol (e.g., vodka, tequila).

Where Does Alcohol Come From?

Just about any plant matter can be used to produce alcohol. Here are the source materials for several popular alcoholic beverages:

• Ale: Fermented from malt with hops
• Beer: Brewed and fermented from malted cereal grain (e.g., barley), flavored with hops
• Bourbon: Whiskey distilled from a mash of not less than 51 percent corn and aged in new charred oak barrels for at least two years
• Brandy: Distilled from wine or fermented fruit juice
• Cognac: Brandy distilled from white wine from a specific region of France
• Gin: Distilled or redistilled neutral grain spirits from a variety of sources, flavored with juniper berries and other aromatics
• Rum: Distilled from a sugarcane product such as molasses or sugarcane juice
• Sake: Produced by a brewing process using rice
• Scotch: Whiskey distilled in Scotland typically from malted barley
• Tequila: A Mexican liquor distilled from blue agave
• Vodka: Distilled from a mash of potatoes, rye, or wheat
• Whiskey: Distilled from a mash of grain such as rye, corn, or barley
• Wine: Fermented juice of fresh grapes and/or other fruit (e.g., blackberry wine)

Any material that contains sugars or starches could be used as a starting point for fermentation to produce alcohol.

Difference Between Distilled Spirits and Fermented Beverages

Although all alcohol is produced from fermentation, some beverages are further purified via distillation. Fermented beverages are consumed as is, possibly after filtration to remove sediments. The fermentation of grain (beer) and grapes (wine) can produce other byproducts, including toxic methanol, but they are present in low enough amounts that they don't typically cause health problems. 

Distilled beverages, called "spirits," start out as fermented beverages, but then distillation occurs. The liquid is heated at a carefully controlled temperature to separate components of the mixture based on their boiling points. The portion that boils at a lower temperature than ethanol is called the "heads." Methanol is one of the components removed with the "heads." The ethanol boils next, to be recovered and bottled. At a higher temperature, the "tails" boil. Some of the "tails" may be included in the final product because these chemicals add unique flavor. Sometimes additional ingredients (coloring and flavoring) are added to distilled spirits to make the final product.

Fermented beverages usually have a lower alcohol content than spirits. A typical spirit is 80 proof, which is 40 percent alcohol by volume. Distillation may be considered a method of improving the purity of alcohol and of concentrating it. However, because water and ethanol form an azeotrope, 100 percent pure alcohol can't be obtained by simple distillation. The highest purity of ethanol that can be obtained by distillation is called absolute alcohol.