Tequila is a Mexican spirit distilled from agave. Tequila has enjoyed a huge surge in popularity outside of Mexico in recent years, with classic cocktails like Margaritas and Palomas now a mainstay on drinks menus, and people opting to sip on premium Tequila.

Tequila production is one of the most tightly regulated in the spirits industry, although there’s a large variety of production methods and styles of Tequila within the category. This guide will give you an overview of the key steps in Tequila production and the different styles of Tequila to be found, so you can be well informed when choosing from the extensive range of Tequilas here at Master of Malt.

Who regulates Tequila?

Although agave spirits have been distilled across Mexico for centuries, they’d previously tend to all fall under the umbrella term of mezcals. There was a concentration of distilleries around the town of Tequila in the state of Jalisco that were producing spirit with a distinct enough style that it was called Tequila. It was only in 1974 that the term Tequila was officially declared as the intellectual property of Mexico and it was given a geographical indication (GI). The formation of the Consejo Regulador del Tequila (CRT) followed this in 1994, and is the governing body that regulates Tequila production. The specifications for making Tequila are set out in the official standard NOM-006-SCFI-2012.

Where is Tequila Made?

Mexico! Anything labelled as Tequila has to be made in Mexico. And specifically, it can only be made in, and using agave grown in certain areas; these are the state of Jalisco, as well as certain municipalities in the states of Michoacán, Nayarit, Guanajuato, and Tamaulipas. These areas have been chosen as they share geographical characteristics that make them well suited to growing the type of agave used in Tequila production.

It all starts with agave.

Agave

All Tequila is made from one type of agave, Agave tequilana Weber Azul variety that’s native to Mexico. You’ll also see it being called blue agave. This plant has a bluish tinge to its fleshy, spiky leaves, and often gets mistaken for a cactus. But it’s actually more closely related to asparagus! These agave plants can grow to over two metres in height, and take around five to 14 years to reach maturity.

A note on maturity, bats, and sustainability

How long agave for Tequila is grown before it is harvested is something that’s come into focus more recently. Blue agave only flowers once in its lifecycle, when a tall stalk (called a quiote) with yellow flowers grows from the centre, when the plant is around five to seven years old. Although this varies.

Just before flowering, the concentration of sugars in the plant is at its highest, which is good news from a production point of view. More sugar means more alcohol. However, after flowering, the agave ends its lifecycle, so growers will tend to chop emerging flowering stalks off so that the plant redirects its energy into growing larger, and storing more sugar.

A tall quiote stalk growing out from the centre of an agave plant.

A flowering quiote growing from an agave plant.

This is where bats also come in. For lesser long-nosed bats, agave flowers are a key food source, and for agave plants, lesser long-nosed bats are the primary pollinators. These bat populations are under threat, with reduced food sources being one of the reasons for this. Growers are being encouraged to let some of their agave crop flower to support bat populations. A recent initiative aims to make this visible to consumers, and Tequila where 5% of the agave crop has been allowed to flower can display a label on the bottle certifying that it’s Bat Friendly™.

Bats pollinating agave flowers also has benefits for the genetic diversity of the plant. Blue agave has been clonally propagated by replanting shoots that appear at the bottom of the plant, which means that farmed agave used for Tequila has very low genetic diversity as it’s mostly copies of the same plant. This is especially bad when it comes to pathogens affecting blue agave, as genetic diversity means they’re better able to withstand pathogens.

For Tequila producers, the long time it takes to grow blue agave, coupled with the increasing demand for Tequila, puts pressure on the supply chain, and it can be tempting to harvest plants before they reach peak maturity. However, it’s a balancing act; with many producers and drinkers choosing Tequila that states longer growing times, which tends to imply more considerate growing practices; and others choosing to use younger plants, preferring the character of the Tequila they make.

Agave harvesting

Harvesting blue agave is a highly skilled job carried out by jimadores. Due to the terrain where agave grows, and their shape, this is a job that’s still primarily done by hand, although some places use machinery to trim some of the spiky outer leaves (pencas).

A jimador using a coa to trim the spiky outer leaves off of the agave plant.

A sharp coa is used to trim the pencas to reveal the piña, which will be used to make Tequila.

A jimador uses a tool called a coa de jima, which looks like a sharp, round shovel. With a coa, the jimadores trim some of the pencas off, before lifting the agave plant out of the ground. This isn’t without its risks; agave fields make a pretty cosy home for all sorts of snakes; the sap from agave contains irritating crystals called ‘raphides’ which can lead to dermatitis; and you could lose a few toes if you don’t know what you’re doing with a razor sharp coa. Best left to the professionals we reckon.

The coa is then used to cut back the remaining leaves, revealing the large, sugar-filled inner heart of the agave called the piña, which looks a bit like a giant green and white pineapple. This is what will be used to make Tequila.

How much of the penca is trimmed off varies, some producers choose to use piña with a fair amount of the green penca left on, and others prefer to trim it down so the piña is nearly all white.

Before it gets cooked, piñas are chopped into pieces and the cogollo is removed. The cogollo is a bud-like section that forms at the top of the piña. It tends to be removed as leaving it in can result in unwanted flavours in the final Tequila – although sometimes it’s left in.

Cooking agave

Agave needs to be cooked because it stores carbohydrates as inulin, which yeasts can’t ferment. Cooking the agave converts inulin to fermentable sugars which yeasts can then turn into alcohol.

A sunken stone fire pit with a mound of crushed agave inside.

An old school sunken fire pit for cooking agave.

There are several methods for cooking piñas. One of the oldest methods is a sunken fire pit called a horno de pozo, but this is now rarely used for Tequila as methods more suited to large-scale production have become popular.

The view of a doorway into a large stone oven that's full of cooked agave.

Stone or brick oven (horno) full of cooked agave.

Steam cooking piñas in large ovens is common now, and two main methods are used. Hornos de mampostería, or hornos, are ovens made of stone or brick. Piñas are put into these sealed ovens and steam is injected to cook the agave before it is left to cool down. This entire process can take anywhere from two to three days to complete.

A man filling a large autoclave oven with chopped agave hearts.

Autoclaves being filled with agave, ready to be cooked.

Another method to cook agave for Tequila is using autoclaves, which are large, pressurised, steam-injected ovens. Autoclaves can reduce the entire time taken to cook and cool the agave dramatically, although the pressure can be reduced to cook the piñas more slowly. The capacity and reduced processing time of autoclaves makes them particularly suited to large-scale Tequila production.

What are diffusers?

Arguably one of the most controversial topics in the world of Tequila. Diffusers are a recent piece of machinery used in large-scale production that extracts fermentable sugar from piñas. Cooked or uncooked piñas are finely shredded to extract the juice, and the remaining fibres are rinsed with water and some acid to extract any remaining sugars. When uncooked piñas are put through a diffuser, the extracted liquid is then cooked to convert the inulin into fermentable sugar.

People in favour of diffusers usually point to the time-saving and environmental benefits, citing them to be more energy efficient than ovens, with very little fermentable sugar wasted with around a 95% extraction efficiency.

Many producers and Tequila drinkers oppose the use of diffusers, especially when used for uncooked agave, claiming they make Tequila too far removed from the complex characteristics that people love.

Extracting the juice

After cooking, liquid full of fermentable sugars is extracted from the piñas. The most old-school method is by hand using mallets, but this is very rarely used now.

A circular tahona, filled with cooked agave.

A tahona filled with cooked agave.

Another traditional method is using a tahona. This is a sunken pit where a large stone wheel is pulled around the pit to crush the cooked piñas. The stone can weigh around two tonnes and was traditionally pulled by a donkey, although nowadays they’ve been replaced by tractors. A small number of Tequila producers still use this method, which has now been largely replaced by mechanised mills that crush the piñas and extract the juice from the fibres. The can range in size and complexity, from fairly small to industrial sized machines. And then there are diffusers, which are mentioned above.

The view of a factory floor in a Tequila production facility, showing a person operating a large roller mill.

Large-scale mechanised mills are more common nowadays for crushing agave.

Fermentation

Tequila makers have plenty of choices to make when it comes to deciding how to ferment the sugary liquid from cooked agave to make Tequila. 100% agave Tequila doesn’t have any extra sugar added when the juice from the crushing process is fermented, but sugar from a variety of sources can be added before fermentation to make ‘mixto’ Tequila.

Mixto Tequila can have up to 49% of the fermentable sugar come from sources other than agave. Tequila made like this doesn’t need to declare this on the label and is simply called Tequila, and many brands of Tequila will be mixto varieties. Tequila made from 100% agave can state this on the label, and most producers using this method will decide to do so.

A person stirring a large open wooden vessel that's full of fermenting agave.

Open wooden vessels are a popular choice for fermenting agave.

Fermentation can happen in many different vessels, usually open or closed wooden, cement, or stainless steel tanks. Yeast and nutrients can be added to the mixture, or it can be left to ferment spontaneously thanks to the natural yeasts and bacteria in the atmosphere of the distillery. Spontaneous fermentation is often a long process, and this slower style of fermentation gives huge amounts of flavour and aroma to Tequila. Faster fermentations won’t have as much time to develop some of the more complex flavours. A bit like sourdough bread vs your standard loaf.

Sometimes, fibres left over from crushing the piñas are added to the fermentation mixture, which can help with creating more flavourful Tequilas, and aid the fermentation process in general by creating a sort of lid on open air tanks.

Distilling Tequila

Tequila can be distilled on many different types of still as the regulations don’t specify any particular type must be used. Originally clay stills would have been used, but nowadays stills tend to be small or large-scale pot and column stills.

Regulations state the final Tequila product must comply with specific organoleptic characteristics – the sensory things like smell, colour, and taste – and there are limits on how much of things like methanol and higher alcohol can be present. Most Tequila will fit these categories after two distillations, although three distillations isn’t unusual. A few producers choose to distil their Tequila four times or more, although then much of the flavour gets lost.

Large distillation apparatus in a Tequila production facility.

The stills used to distil Tequila can vary in size.

What happens after distilling Tequila?

After distilling, Tequila can be aged or unaged, and comes in five categories (blanco, joven, reposado, añejo, and extra añejo). Any shape of oak container can be used to mature Tequila, as long as it’s made from oak or holm oak (Quercus ilex). If you want to find out more about the five categories of Tequila, as well as some other styles like cristalino Tequila, check out this guide on the different styles of Tequila.

Additives, abocado, and Tequila

All categories of Tequila allow the use of additives to ‘soften’ the taste of Tequila. There’s a bit of confusion around how this applies to blanco Tequilas, as contradicting sections of the official standard mean a loophole exists where additives can be added to blanco Tequilas, and in practice many producers choose to do so.

Collectively, these additives are referred to as abocantes, and include caramel colouring (like the one used in whisky), oak extract, glycerin, and sugar syrup. These are set at limits of a maximum of 75g/L of sugars and 85g/L of dry extract, and no more than 1% of the Tequila can be made up of these additives.