Beer, wine, and liquor all contain some amount of ethyl alcohol, or ethanol - distinct from other kinds of alcohol, such as rubbing alcohol, which is poisonous if taken internally. In its purest form, ethanol is colorless and odorless.
Ethanol is made by two methods:
- Fermentation is a natural process that occurs when yeasts combine with plants like potatoes, fruits, and grains. When the sugar in the plants sits for a while with the yeast, it produces an enzyme that converts into alcohol. Natural fermentation can produce alcoholic beverages like beer and wine that contain up to 14% ethanol.
- Distillation is a simple mechanical process that starts with boiling fermented fruit or grain mixtures. Since alcohol boils at a lower temperature than other liquids, it turns into steam sooner and separates from those liquids. The steam is caught in a cooling tube and transferred to a different container where it turns back into liquid, leaving the other liquids behind. When the alcohol liquid is distilled several times, it can produce up to 95% pure ethanol. Distillation is typically used to produce spirits, also known as liquor (e.g. rum, vodka, whiskey, etc.).
"Proof" is the standard measurement of the amount of alcohol in a product. It is based on a formula that expresses ethanol concentration or percentage. Proof appears on labels of foods and beverages that contain alcohol. Generally, the proof number on a label equals two times the percentage of alcohol in that product.
The ethanol concentration, or proof, of different types of popular beverages varies widely.
- Beer: 8-12 proof (4%-6% ethanol)
- Wine: 14-28 proof (7%-14% ethanol)
- Distilled spirits (also known as liquor): 80-190 proof (40%-95% ethanol)
The majority of distilled spirits sold in liquor stores are 80 proof (40%) and 100 proof (50%) alcohol. Some highly concentrated forms of rum and whisky run as high as 75%-95%. For example, Everclear, a brand of grain alcohol, is distilled to concentrations of 190 proof (95%) and 151 proof (75.5%) alcohol. (It is illegal to purchase the 190 proof version of Everclear in many U.S. states. This is due to the fact that it is clear, odorless, and so potent that consuming it can be very dangerous.)