By: Derek Martinez
Mezcal is one of the most iconic beverages in Mexico, especially in the state of Oaxaca, where it originates from. It is a distilled alcoholic beverage made of agave (of the genus maguey), and is made of more than 14 types of agave, and can have different appearances, tastes, and odors depending on the type of agave being used.
The production of Mezcal is an artisanal process, requiring several time consuming steps. Surprisingly, there is a lot of science involved in creating the Mezcal, especially in the fermentation and distillation steps of the process. Though there are no additional chemicals added (sometimes substitutes are used) in order to make a natural mezcal, there are several chemical processes that give the product a unique flavor.
Though the process varies, the general steps for making mezcal are to harvest and cut agave, cooking it, mashing it, fermentation, first distillation, second distillation, and then cask maturation. The cooking stage involves forming a bonfire within a stone underground pit, and letting the fire die down. After that, stones covered in wet agave fiber are added, and then the agave is added, being cooked slowly and developing an earthy flavor from the stone pit. After several days, the agave is mashed and made into fiber and wet pulp, preparing it for fermentation.
The fermentation process is one of the most important and interesting steps. The mashed agave ferments naturally, with only water being added to the distillery. The duration of fermentation depends on several factors, such as sugar content, temperature, and altitude. The mezcal is fermented by ambient yeasts and microbes endemic to the distillery being used. The flavor produced can vary depending on the type of agave being used, as each type has a variety of terpenes compounds (terpenes are a class of hydrocarbons found within plants and animals and is built up from isoprene. They are typically used for fragrances and flavors in consumer products). The main chemical products in the fermentation process are ethanol, methanol, n-propanol, 2-butanol, and acetic acid. The total process takes from 1-4 weeks, all depending on the chemical factors mentioned.
After fermentation the agave is added to a still for distillation. There are multiple types of stills, depending on the geographical region in which the mezcal is being produced. Distillation involves heating and cooling a liquid to purify it, in this case, the agave mash. Alcohol is added to the first distillation, and during the second distillation, both the mash and alcohol which was previously distilled is added to the still. The final product is bottled and sold, and can be left to age for up to 12 years and reach an alcohol content of 55%.
In our current world, products are materialistic and focus on the speed of production rather than the whole quality of the product. Examples of rich beverages like mezcal show that there is actually quite a lot to appreciate about gastronomy and the chemistry behind cooking. Next time you cook something, take some time to learn about the science behind your food, and experiment a bit!
Q: What does the distillation process involve?
A: Distillation of a liquid involves heating and cooling it in order to purify it. With mezcal, alcohol is added to the first distillation along with all of the agave product, and is added again into a second distillation after the first. The distillation process results in a higher concentration of alcohol, and also generally allows the mezcal to develop its unique flavor.
Q: How does the chemical structure of different agave plants affect its flavor?
A: Different agave species have a different variety of hydrocarbons called terpenes. The terpenes are what give it a distinctive flavor and smell, and can result in a different tasting and smelling mezcal. Though not directly related to the plant species, the final flavor of the mezcal can also be affected by the yeasts and microbes that are within the distillery being used for the fermentation and distillation stages.