Tequila is made from the distilled juice (or sap) of the blue agave plant. The blue agave is similar in appearance to cactus, but is a type of amaryllis. During the production process, fresh juice is added to pre-fermented juice and then distilled, which converts sugars in the plant into alcohol and produces the spirit we know as tequila.
Agave juice is the fresh sap of the blue agave plant. Liquor must contain at least 51 percent distilled blue agave juice to be considered tequila; if it doesn't reach this level, it is known as mescal. The juice is extracted from the agave by removing the heart of the plant once it reaches around 12 years old, then stripping the leaves and heating the heart to extract the sap.
Pulque is blue agave juice that is pre-fermented before being added to fresh juice at the beginning of the tequila production process. It is allowed to rest and ferment for ten days, with the end result often referred to as 'mother pulque'. This process starts converting the plants sugars into alcohol and is essential to making tequila. Once mixed with the fresh juice, the mixture is double-distilled in pot stills.
Blue agave has high amounts of naturally occurring sugars, and so is ideally suited to the production of alcohol. The end result of the double-distillation process is tequila blanco, which has an alcohol content of between 38 and 40 percent (80 proof). Some tequila distilleries actually distill to 100 percent proof, before diluting with water to reduce the drink's harshness. Tequilas generally range between 38 percent and 55 percent.
Types of Tequila
There are three broad categories of tequila, each defined by their age. Tequila blanco is the youngest and is the direct result of the double-distillation process. It has foreground blue agave flavors and a sharp, strong alcoholic taste. Reposado is aged, and has a darker color than blanco. Añejo is aged in oak barrels, and acquires a light brown color with age as well as a refined depth of flavor.