Mezcal Union is produced and distilled in San Baltazar, in the state of Oaxaca. It is made with three different types of agave: Espadín, Cirial and Barril and is produced by a group of families.
Espadin Agave grows for 6-8 years before harvesting, Barril Agave for 8-10 years, and Cirial 20 years. Barril and Cirial are both wild Agave. Once the Agave is harvested, and the piñas are ready to be roasted, a fire is started in the base of a earthen pit, with river stones placed on top. Once the rocks are red-hot, the piñas, which have been cut in half or in quarters, are placed in the pit. The entire pit is then covered with agave leaves and fiber and straw mats, piled up with earth and left to roast for four days.
The roasted agave is crushed by a Tahona, pulled via horse or mule. Once extracted, the mash is placed in wooden barrels with water and left to ferment for several days. After the fermentation, the mash is distilled. The first distillation yields low-grade alcohol. The fibers are then removed from the still and the alcohol from the first distillation is distilled a second time. After the second distillation, the mezcal is blended to obtain a consistent grade of alcohol. Then, Mezcal Union is bottled.
Palenques are the distilleries where these families produce their artisanal mezcal. Mezcal Union is associated with 30 of these families. Families that form part of the Union of Mezcal have more than three generations producing mezcal as their main craft.