Where Does Alcohol Come From?

All alcoholic beverages contain ethanol. Any plant can be used as a source material, although fruits and grains work best because they are naturally high in the carbohydrates needed for fermentation.
All alcoholic beverages contain ethanol. Any plant can be used as a source material, although fruits and grains work best because they are naturally high in the carbohydrates needed for fermentation. Nick Purser / Getty Images

The alcohol that you can drink is ethyl alcohol or ethanol. It is produced by fermenting carbohydrates, such as sugars or starches. Fermentation is an anerobic 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 may be used (e.g., wine) or distillation may be used 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 is a list of the source material for several popular alcoholic beverages.

Ale - fermented from malt with hops

Beer - brewed and fermented from malted cereal grain (as 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 a minimum of two years

Brandy - distilled from wine or fermented fruit juice

Cognac - a 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

Tequila - a Mexican liquor distilled from blue agave

Vodka - distilled from a mash as of potatoes, rye or wheat

Whiskey - distilled from mash of grain such as rye, corn, or barley

Scotch - whiskey distilled in Scotland typically from malted barley

Wine - fermented juice of fresh grapes and/or other fruit (e.g., blackberry wine)

When you get right down to it, any material that contains sugars or starches could be used as a start 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 by-products, including toxic methanol, but these by-products are present in low enough amounts 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% alcohol by volume.