Waste Not Want Not: Olla de Barro (Clay Pot) Ancestral Mezcal Distillation in Oaxaca

Written and photographs provided by Alvin Starkman, M.A., J.D. 

The start-up costs of building a traditional, artisanal mezcal distillery or palenque in Oaxaca are significant, the most costly out-of-pocket expense being the copper still or alembic. But once that expenditure has been made, the brick and cement outer buildings erected and the limestone tahona purchased, there’s little cost in maintenance. In fact often the copper need not be repaired or replaced for upwards of a quarter century. By contrast, building a clay pot or olla de barro ancestral mezcal distillation facility involves relatively little monetary outlay. However the ongoing upkeep expenses have the potential to be significant and out of reach for many palenqueros of modest means … but for their ingenuity.

Most of the clay pots employed in ancestral mezcal production in and around the central valleys of Oaxaca are produced in the town of Santa María Atzompa.  They are made with locally sourced clay, water and fire, and thus their cost is little, perhaps 800 pesos for the two receptacles required to make one still.  Contrast this with some 80,000 pesos for a 300 liter copper alembic.

The housing which encases the bottom clay pot is made from locally produced clay and/or adobe bricks and mud, and nothing more. The adobe is made by mixing sand, mud, perhaps donkey, sheep, bovine and/or equine excrement, and waste agave fiber or bagazo discarded after the first distillation.

Clay pots last anywhere from a couple of weeks up to no more than about a year and a half, after which time they must be replaced.  It’s that bottom pot, as opposed to the upper clay cylinder which presents the more significant problem, since once it cracks or breaks, the housing must be disassembled, the pot removed, a new one inserted, and finally the encasement re-built. The life of that bottom olla is extended by using not a metal pitch fork to remove the bagazo, but rather a wooden tree branch in the shape of a fork, its prongs sometimes joined with rope or wire. The cost is virtually nothing.

But clay pots are inevitably rendered unusable for their intended purpose through breakage and cracking.  When it happens the fermented liquid or the subsequent single distillate seeps out.  The damaged pots and upper chamber clay cylinders are frequently used as planters. But that bottom discarded pot has a more important use, that is, in the fermentation process. Most baked crushed agave is fermented in pine or oak vats with capacity of usually 700 – 1,000 liters. But some palenqueros ferment in clay pots, typically partially embedded in the ground. After a damaged pot has been removed from the still housing, it can be simply repaired with cement and used for fermenting; a repaired pot should not be used for distillation anew.  And so while a cracked or broken olla de barro is not reusable for its original reason for purchase, it gets new life.

In order for clay pot distillation to work, a continuous flow of cold water is required. It often arrives along a makeshift wooden trough, falling into the small conical condenser through a length of giant river reed or carrizo. Carrizo is an invasive wild vegetation with multiple uses, including in the ancestral olla de barro distillation process. In addition to the foregoing use, it is sometimes employed to guide the water out of the condenser, and the distillate out of the still into a holding receptacle.  The receptacle is sometimes a different type of clay pot known as a cántaro, produced in a different village and made from a rather unique clay. And yet another use for the invasive carrizo is as a bellows to stoke the flame under the olla de barro during distillation.

Long ago palenqeros used clay condensers in the distillation process. When metal became available, they switched.  They now typically use simple laminated metal, however more recently stainless steel or copper. But some have adapted old aluminum construction worker hardhats. The shape is about the same, and with a little work they are close to as efficient as the others. When in or about 2012 I first visited the palenque of Sola de Vega’s Tio Rey of Mezcal Vago notoriety, he had been using hard hats as condensers!  Now we all know the quality of this palenquero’s mezcal; exquisito as they say.

The steam rises, hits the condenser, then the drops of liquid must fall onto something which then guides the liquid to the exterior of the cylinder, through yes that different piece of carrizo, and down into the container. That something is typically a hand-hewn wooden spoon, or a small length of agave leaf or penca. And, the condenser is sealed to the upper cyclinder, and it’s sealed to the lower olla de barro, not with glue, but rather the paste which naturally forms on the top of the fermentation pot.

When the still is not in use, many palenqueros prefer keeping the opening underneath, into which firewood is placed to produce the flame, closed off. I’ve heard by some that they don’t want their young children playing hide-and-seek in the sooty and sometimes still hot orifice. Others don’t want their chickens laying eggs inside. Maestro Felix Ángeles Arellanes of Santa Catarina Minas, keeps the opening closed using old metal discs from a plow.

At the outset I noted the modest start-up costs for establishing a palenque for olla de barro distillation, and touched upon the cost of the clay pots. Installations in both clay and copper operations which are pretty well free of out-of-pocket costs require only labor,  include the pit in the ground for baking, the opportunity to crush by hand using a wooden mallet and nothing more, and fermenting in an animal hide or a lined hole in the earth or directly in a bedrock cavity. But it’s in particular the innate creativity of the palenquero distilling in clay, which is remarkable. And while we must admire his ingenuity and resourcefulness, it’s crucial that we not begrudge him for making technological and simple material advancements with a view to making life just a little easier, as his economic lot in life improves.

Alvin Starkman operates Mezcal Educational Excursions of Oaxaca (www.mezcaleducationaltours.com).