How It Works

Mezcal is one of those spirits where the how is inseparable from the what. The smoke in the glass is a direct record of a decision made at the pit. The label tells a story about soil, species, and certification. This page maps the production mechanism, the regulatory structure that governs it, and the tracking points that distinguish one bottle from the next — from agave in the ground to certified spirit on a shelf.

Where oversight applies

The Consejo Regulador del Mezcal — known by its initials CRM — holds certification authority over mezcal production in Mexico. Without CRM certification, a distilled agave spirit cannot legally be sold as mezcal, whether in Mexico or exported to markets like the United States. The CRM operates under NOM-070-SCFI-2016, the official Mexican standard that defines what mezcal is, how it must be made, and who can make it.

That jurisdiction is geographically bounded. The mezcal denomination of origin covers 9 Mexican states: Oaxaca, Guerrero, Durango, San Luis Potosí, Zacatecas, Michoacán, Tamaulipas, Guanajuato, and Puebla. A maestro distilling agave spirits in Jalisco — unless that specific municipality has been included — is outside the denomination, and the resulting spirit cannot carry the mezcal name regardless of how it was made.

Within those 9 states, the CRM assigns a lot number to each certified batch, which becomes the NOM code printed on the label. That code is traceable: it identifies the specific producer and palenque (distillery) where the mezcal was made.

Common variations on the standard path

NOM-070 establishes three production categories, and the differences between them are not subtle.

1. Industrial mezcal permits autoclave cooking, diffuser extraction, and column distillation — methods that prioritize volume and consistency over artisanal character. Few brands in the US premium market operate at this level, but the category legally exists.

2. Artisanal mezcal allows above-ground roasting ovens (hornos de mampostería), tahona or mechanical shredder extraction, and wooden or clay pot distillation with a copper or clay still. This is the category covering most recognizable mezcal brands.

3. Ancestral mezcal is the most restrictive: agave must be cooked underground in earthen pits, crushed by tahona or hand mallets, fermented in natural vessels, and distilled in clay pots (ollas de barro). No copper pot stills. No mechanical assistance. The result is often lower-yield and higher-ABV. A detailed breakdown of how these tiers interact with flavor and price is covered on the artisanal vs ancestral vs industrial mezcal page.

The variation doesn't stop at production method. Agave species drives enormous divergence — agave varieties used in mezcal currently number over 40 approved under NOM-070, compared to the single species (Agave tequilana Weber azul) permitted for tequila. Each species matures on a different timeline, produces a different sugar profile, and contributes distinct aromatic compounds to the final spirit.

What practitioners track

Producers, importers, and serious buyers follow a handful of variables that shape what ends up in the bottle.

• Agave maturation: Most espadín plants are harvested at 7–9 years. Wild tobalá may take 12–15 years. Premature harvest reduces sugar content and flavor complexity — a shortcut with measurable consequences.
• Fermentation duration and vessel: Open-air fermentation captures ambient yeasts and microorganisms specific to a palenque's location. Fermentation in animal hides (pieles) is an ancestral marker; pine vats are common in artisanal production. Duration typically runs 4–30 days depending on temperature and inoculant activity.
• Distillation pass count: Most mezcal runs double distillation. A single-distillation spirit exists in some ancestral contexts but is uncommon and will carry lower ABV. Many producers proof-adjust after distillation; others bottle at still strength, which can reach above 50% ABV.
• Lot size: Single-batch production from one harvest of one agave variety, tracked by the CRM lot number on the label, is the baseline unit of traceability. Mezcal collecting and single-batch bottles goes deeper on why lot-level tracking matters to enthusiasts.

The basic mechanism

Strip everything back and mezcal is fermented agave juice that has been distilled twice. But the path from plant to proof is longer and stranger than that summary suggests.

The agave heart — the piña, which can weigh anywhere from 15 to 150 kilograms depending on species — is harvested when starches have converted to fermentable sugars, a biological clock that takes years to run. The piñas are then roasted, traditionally in underground conical pits lined with volcanic rock and fueled with wood, for 3–5 days. This is where smoke becomes flavor: pyrolysis compounds from the burning wood impregnate the roasted agave fibers. Roasting agave for mezcal covers the thermal chemistry involved.

After roasting, the piñas are crushed to extract juice (aguamiel) mixed with fibrous pulp (bagazo). Fermentation — either with wild yeasts, commercial yeasts, or a combination — converts sugars to alcohol over days or weeks. The fermented liquid then runs through distillation, typically twice, emerging as a clear or slightly cloudy spirit.

What differentiates mezcal from nearly every other category of distilled spirits is that this process is still, in a large share of production, performed by a single maestro palenquero managing each step by hand, reading the agave and the ferment with accumulated generational knowledge. The full mezcal production process goes through each stage in detail.

The broader picture — what mezcal is across its full range of species, regions, and styles — is mapped on the mezcal authority homepage.