In the previous process, we were able to learn a little more about how cooked agave fibers are ground to extract the sugars from it. When no more liquid sugars can be removed, the solid, or dry fibers of the agave, called "bagazo" are returned to the fields, where they are treated and later used as compost.
Now, everything is concentrated in the liquid, the sugars, the really important ingredient to start making the tequila.
During fermentation, the sugars present in the musts are transformed, by the action of yeasts, into ethyl alcohol (ethanol) and carbon dioxide. At this stage, other compounds will also be formed that will contribute to the final characteristics of the tequila. Critical factors to control in this phase are temperature, pH and contamination by organisms that represent a competition for yeasts.
This process can take anywhere from 28 to even 96 hours. This depends on the type of tanks used, or if they are closed for example. At Casa Maestri, our stainless steel tanks are open to guarantee a more transparent and careful fermentation process, in addition to providing an incredible spectacle. Fermented temperatures range from 32 to 40 degrees Celsius.
Casa Maestri's fermentation tanks
According to the Consejo Regulador del Tequila, the tequila manufacturer can make two categories of tequila, which are 100% agave tequila and tequila respectively. The 100% agave tequila is made from the sugars extracted from the agave exclusively and therefore, it can only consist of sending the juices to the fermentation tanks and the addition of yeasts, the result of this operation is the "mosto".
However, in the case of the plain tequila category, it can be made with the participation of up to 49% of sugars from a source other than agave; in this case, the formulation consists of a mixture of the sugars extracted from the agave and from another source. In addition to the above, yeasts are added, resulting at the end of this phase, the "mosto" ready to start the fermentation process.
And why do we say that the fermentation process provides a great spectacle? Because the alive mosto or "mosto vivo" moves in beautiful patterns, almost like dancing, when yeast is working correctly through the sugars of the agave.
"Mosto vivo" in fermentation phase. Photo taken from "Sip Tequila Blog"
Beautiful colors and "worm like" shapes are formed during the fermentation and it is a very interesting process to watch. And then, just like that, we've made our way into distillation.
Thank you for joining us during the production stages on our blog. Next week we will talk about distillation and more details. Don't forget that you can download the Casa Maestri app in the App Store and Google Play Store.