Mezcal is a Mexican distilled spirit made from the agave plant. There are many different types of agaves, and each produces a slightly different mezcal. Agave is part of the Agavaceae family, also called maguey. Tequila is a mezcal made only from the blue agave plant in the region around Tequila, Jalisco.

Production

Mezcal is made from the heart of the agave plant. After the agave matures (6-8 years) it is harvested and the leaves are chopped off, leaving only the large hearts, or piñas (Spanish for "pineapple"). The piña is then cooked and then crushed, producing a mash.

Traditionally, the piñas were baked in palenques: large (8-12 ft diameter) rock-lined conical pits in the ground. The pits were lined with hot rocks, then agave leaves, petate (palm fiber mats), and earth. The piñas are allowed to cook in the pit for three to five days. This lets them absorb flavors from the earth and wood smoke.

After the cooking, the piñas are rested for a week, and then placed in a ring of stone or concrete of about 12 ft diameter, where a large stone wheel attached to a post in the middle is rolled around, crushing the piñas.

Modern makers usually cook the piñas in huge stainless steel ovens and then crush them with mechanical crushers.

The mash is then placed in large, 300-500 gallon wooden vats and 5%–10% water is added to the mix. The mash (tepache ) is covered with petate and is left to naturally ferment with its own yeasts and microbes for four to thirty days.

To the resulting mash, cane and corn sugars, as well as some chemical yeasts, may be added. The government only requires that 51% of this mix be from agave. The resulting mix is then fermented for a couple of days in large stainless steel vats.

After the fermentation stage is done, the mash is double-distilled. The first distillation yields ordinary low-grade alcohol. After the first distillation, the fibers are removed from the still and the resulting alcohol from the first distillation added back into the still. This mixture is distilled once again. Sometimes, water is then added to the mix to reduce the proof down to 80. At this point the mezcal may be bottled or aged.

Mezcal ages quite rapidly in comparison to other spirits. It is aged in large wooden barrels for between two months to seven years. During this time the mezcal acquires a golden color, and its flavor is influenced by the wooden barrels. The longer it is aged, the darker the color and more noticeable the flavor.

Age classifications:

• Añejo – Aged for at least a year, in barrels no larger than 350 litres.
• Reposado (rested) – Aged two months to a year.
• Blanco – White (clear) tequila, aged less than two months.

The worm

The worm in the mezcal bottle is a marketing gimmick. The worm is actually the caterpillar Hipopta Agavis . The originator of this practice was a man named Jacobo Lozano Páez. In 1940, while tasting prepared agave, he and his partner found that the worm changed the taste of the agave. (Agave worms are sometimes found in the piña after harvesting, a sign of badly chosen, infested, agave). Brands of mezcal that contain the worm include 'Gusano de Oro', 'Gusano Rojo', 'Monte Alban', and 'Dos Gusanos'. Contrary to public belief, tequila is, by law, not allowed to contain the worm.