Tequila or mezcal? What separates the two, from agave to oven to law

The first difference is the plant. Tequila comes from blue Weber agave only, Agave tequilana Weber variedad azul, as the Consejo Regulador del Tequila states. Mezcal’s standard, NOM-070-SCFI-2016, defines the raw material as any species of the genus Agave, wild or cultivated, harvested mature inside the denomination zone, and the label names the species used.

In practice a few species dominate. Difford’s Guide reports that espadín, Agave angustifolia, makes as much as 90% of all mezcal, because it is easy to grow, matures in about five to nine years and yields well. Tobalá, Agave potatorum, and tepeztate, Agave marmorata, are examples of slower and rarer plants, and Difford’s says tepeztate yields around a third as much as espadín from the same weight. We name them as examples, not as a ranking.

Difford’s Guide adds that NOM-070 does not name permitted varieties, and that some mezcal makers use blue agave too. Tequila is the narrower rule on the plant and mezcal the wider. The plant on the label is a reliable guide to what you are tasting.

The CRT lists 181 municipalities across Jalisco, Michoacán, Guanajuato, Nayarit and Tamaulipas for tequila. COMERCAM, the body that certifies mezcal, lists the denomination of origin as Oaxaca, Guerrero, San Luis Potosí, Zacatecas and Durango in full, plus municipalities in Puebla, Michoacán, Tamaulipas and Guanajuato. That is nine states. COMERCAM adds that 2018 additions covering parts of the State of Mexico, Aguascalientes and Morelos, and the recent inclusion of four municipalities in Sinaloa, are under appeal.

Oaxaca is the name most linked with it. Difford’s Guide says mezcal production is most identified with Oaxaca and its neighbours Guerrero and Puebla, while tequila centres on Jalisco. COMERCAM dates the denomination to 1994, twenty years after tequila’s, and says NOM-070 confines both the agave and the bottling of mezcal to the denomination zone.

Both spirits start with cooked agave, and the cooking differs. The CRT describes tequila’s as a hydrolysis that can take up to six hours at 120 to 125°C, and Difford’s Guide notes that the tequila standard does not require a traditional oven.

NOM-070 allows plain mezcal to be cooked in underground ovens, stone basins or an autoclave, and milled with a tahona, a mill, a shredder or a diffuser. For mezcal artesanal, the standard requires excavated cooking pits or raised stone basins, with direct flame stills of copper or clay. Mezcal ancestral goes further: stone pits, milling with mauls, tahona or mills, and distillation in a clay pot.

The rest of the process differs too. NOM-070 lists fermentation in wood, stone tanks or steel for plain mezcal, and in stone, soil, tree trunks, animal skins or clay for artesanal and ancestral mezcal, where the fibre may stay in. Tequila fermentation, by the CRT’s account, is in tanks with yeast. Difford’s Guide adds that column distillation cannot be labelled artesanal or ancestral, so those two categories are pot-still spirits.

Smoke follows the method. Difford’s Guide explains that pit ovens and masonry ovens slowly roast the piñas, caramelising them, and that pit ovens give a delicate smoky note. Autoclaves roast in days, not weeks, and tend not to give the same flavours. So not all mezcal is smoky, and the smoke in the ones that are comes from the oven, not from anything added to the bottle.

Sources for the table: the CRT, NOM-006, NOM-070, COMERCAM and GOV.UK’s register.

NOM-070 sets three categories by how the spirit is made: mezcal, mezcal artesanal and mezcal ancestral. They sit on top of a second label term, the class. A bottle can therefore be an artesanal young mezcal or an ancestral reposed one.

The classes cover age and flavour. White or young mezcal has had no further processing. Matured in glass has rested more than 12 months in a glass container. Reposed has spent two to 12 months in wooden containers of any size. Aged has spent more than 12 months in wooden containers of less than 1,000 litres. The standard also names two flavoured classes, mezcal flavoured with and mezcal distilled with other ingredients.

Compare that with tequila: reposado at two months and no cask limit, añejo at a year and 600 litres at most. The two systems are alike in outline and different in detail, so a reposado on a mezcal label and a reposado on a tequila label do not promise the same cask or the same time.

The label carries more than the class. NOM-070 requires the words 100% maguey or 100% agave, the traditional or scientific name of the agave, the state where it was made and the words protected denomination of origin. If two or more species were used, the label lists them in decreasing order. For matured in glass and aged mezcal it also gives the time in whole years.

Start with the type and the class on the label, because together they say how it was made and how long it rested. Next find the agave species, which NOM-070 puts on the label, and the state of production. A mezcal that names two or more species lists them in decreasing order.

The fourth detail is the words 100% agave. For mezcal they are universal, because NOM-070 allows no other sugars. For tequila they mark one of two groups, and the label says so only for the 100% group. That one difference is the reason a tequila label needs more reading than a mezcal one.

The worm is the most familiar mezcal image and the least explained. NOM-070 mentions maguey worms as one of the ingredients that may be added to mezcal in the flavoured class, which means a bottle with a worm in it is not a plain mezcal.

Difford’s Guide says that bottles con gusano contain the larvae of a moth that lives in the agave, and that sal de gusano is a powder of dried worm, salt and chilli sprinkled on the mezcal before it is sipped. It adds that for export markets the worm is now usually a marketing gimmick. Tequila has no worm in any class.

Mezcal is not the only Mexican spirit with a protected name. GOV.UK’s register lists Sotol, Bacanora and Raicilla as Mexican geographical indications, each registered in the UK scheme on 1 September 2021, as it lists Mezcal. Each is a separate registered name, and none is a style of tequila.

A swap changes the drink more than the measure suggests. The Mezcal Margarita is a Tommy’s Margarita with mezcal in place of tequila: 60ml of joven espadín mezcal, 30ml of lime juice and 15ml of agave syrup, with no orange liqueur. Orange and smoke compete for the same part of the palate, and agave syrup sweetens without adding a second flavour.

The Mezcal Negroni keeps the Negroni’s equal parts and changes only the spirit. Mezcal pushes back against Campari with roasted agave and smoke, where gin sits inside the bitterness. Many drinks go further and split the base. The Oaxacan Old Fashioned pours 45ml of reposado tequila with 15ml of mezcal, which Punch dates to 2007 at Death & Co, so the oak carries the drink and the smoke sits on top.

Other mezcal drinks borrow the shape of a classic. The Naked and Famous takes the Last Word’s four equal parts, the Division Bell is the Last Word with two swaps, and the Tia Mia puts mezcal where a Mai Tai has rhum agricole. The Illegal pairs mezcal with Jamaican overproof rum. Where a drink needs the pepper and green agave of tequila instead, use tequila, as in the Margarita.

Strength follows the build. The Mezcal Margarita is about 2.4 UK units and the Margarita about 2.8, because the Margarita adds the alcohol of 20ml of triple sec to the 50ml of tequila. Both spirits are counted at 40% ABV here.

If you are buying one bottle of mezcal for mixing, start with an unaged espadín, as the mezcal ingredient page advises. Taste it neat first, in small sips, beside a blanco from the tequila guide. The difference between the plants shows before any lime goes in.