General information of colonche producers
Colonche production in LG is mainly produced by men, while in MC production is predominantly carried out by women (Table 1). In order to avoid noise in the data, the information from the PZ was removed from our study because of the low sample size and unclear production methods.
Colonche producers in the Altiplano region stated that the beverage is mainly consumed by family members and secondarily sold representing a small source of income (less than 10% of their total income during Opuntia fructification. Colonche has such high value that consumers have found ways to store and transport the beverage to the USA and other regions of Mexico, with the main purpose to share with members of their families.
It is important to highlight that most of the producers learn the production process from their mothers. Also, new producers argue that it was a beverage that their family ceased to produce due to the absence of the mother. Nowadays, they have, once again, began to produce colonche because of its symbolic association with family relations. However, as a main threat for continuing colonche production, the producers interviewed identified the disinterest in colonche production and consumption by the young people, mainly because “it represents more work” and it is not easily available as other beverages like beer. Above all, producers preferred colonche consumption and recognize that the attitude upheld by the younger generations and the substitution of colonche for other beverages like beer endanger the continuation of the production of this historic product.
Colonche is not considered as a medicinal beverage in most of the communities, only 7% of the respondents considered that it has health benefits related to lungs and stomach illnesses, while most of the respondents said that they were not aware of health-related benefits. Most of the respondents consider that colonche has euphoric attributes due to its alcohol content.
In MC, colonche consumption occurs mostly during Sunday’s market; therefore, the production of colonche begins Wednesday. Each household produces at least 20 L to bring to the Sunday market. Unlike MC, colonche in LG is locally consumed within their households and shared with friends and guests. However, a recent festival named “feria del colonche,” which takes place in LG during September has proven to be a very successful way to popularize and share colonche in the region and generate incomes for local producers.
In all villages of the Tehuacán-Cuicatlán Valley, colonche is produced for direct consumption by household members, family meetings and parties. Additionally, colonche is a sub-product associated with the extraction of the seeds of P. weberi, which are highly valued in regional markets [37, 38].
Substrate selection
A total of seven Opuntia species and varieties and six columnar cacti species are used for colonche production in both regions. However, as mentioned above, Opuntia streptacantha is the main ingredient of colonche produced in the Altiplano region and Pachycereus weberi in the Tehuacán Valley. Nevertheless, all the communities add fruits of other Opuntia species when fruits of O. streptacantha are not available. The other species of cactus prickly pears used for colonche production include Opuntia orbiculata, O. robusta, O. hyptiacantantha, O. phaeacantha, and O. ficus-indica. In particular, in LG, O. streptacantha is widely distributed in managed and unmanaged landscapes and producers invest at least 2 h (± 30 min) daily for fruit collection. In contrast, in MC, O. streptacantha is not widely distributed and is only found in private managed properties; as a result, producers propagate O. streptacantha by using cuttings, young plants, and cladodes to establish plants near their houses or within their gardens. If producers of colonche do not directly collect O. streptacantha fruits they purchase or exchange colonche with local growers for access to fruits. In contrast, fruits are widely available in PZ but, nowadays, is rarely produced. In fact, production in PZ was not well characterized because of the lack of producers and information in this region.
In the Altiplano localities, Opuntia prickly pear fruits are collected with a sickle and peeled with a knife in situ. Then, the peeled fruits are placed in plastic containers and transported to the house of the colonche producer. Harvesting can include all family members, and it is performed in the morning to avoid collecting fruits warmed by the sun. Ripe Opuntia fruits are selected for colonche production. Non-ripe fruits have less sugar content and are typically not preferred. If non-ripe fruits are used, more fruits must be collected in order to produce colonche with the same flavor quality. Additionally, red fruits are favored for colonche production, however, when red fruits are scarce, yellow and white fruits could be added resulting in changes in flavor, color, and texture (Fig. 3a).
In the Tehuacán Valley, people from Quiotepec and Coxcatlán prepare colonche (also called “pulque rojo” or “red pulque”) mainly with fruits of Pachycereus weberi or cardón, Polaskia chichipe, Escontria chiotilla, Stenocereus stellatus, S. pruinosus, and Opuntia pilifera. Fruits of these species are produced from late January to early May, the peak of fruit production occurs in April. The exceptions are Escontria chiotilla and Stenocereus stellatus which have fruit production peaks from July to September. In Cuicatlán (Cu), people use the fruit of Opuntia pilifera for preparing colonche. In this town, as well as in Quiotepec (Qu), and Coxcatlán (Co) people commonly use fruits of E. chiotilla. They say they occasionally prepare colonche with fruit of S. pruinosus and S. stellatus, but they say these fruits should be ripe, otherwise, the colonche would be bitter and sour. People said they also have tried colonche preparation with the fruit of Hylocereus undatus, and Lemairocereus hollianus but they do not like neither the insipid flavor nor the viscous texture of colonche resulting from the fruit of these species. In San Luis Atolotitlán (SLA) and Metzontla (Mz), people more frequently use fruit from E. chiotilla, P. chichipe, P. chende, S. stellatus, and S. pruinosus. In all cases, seeds are removed, but only recovered for consumption and commercialization the seeds of S. pruinosus and S. stellatus, particularly those varieties producing larger seeds. People gather cardón fruits by using a “chicol,” which is a long stick, commonly a “carrizo” stem (Arundo donax), whose extreme is cut into strips which are doubled and tied with a wire or palm fibers to form a basket, which is appropriate to pull the fruit down the cardón branches without causing damage to cactus plants.
All of the producers at the Altiplano quantify the yield of two plastic buckets of 25 L of peeled cactus prickly pear fruits that allow obtaining 15 ± 2 L of colonche. Whereas in the Tehuacán Valley, yields are similar, a 20-L bucket of peeled fruit may yield 16 to 17 L of juice, most probably because seeds of columnar cacti are smaller than those of Opuntia fruits. After being collected, fruits are carried from field to homes in buckets, where these are peeled outdoors and then pressed using a cloth, in order to separate juice and seeds, thus catching the seeds.
Production process
Figure 4 illustrates the general process of colonche production and differences in both regions and localities. As mentioned above, in the Altiplano region Opuntia prickly pear fruits are collected and peeled in situ in the morning and transported to the houses by the colonche producers (Fig. 2a), then the peeled fruits are left outdoors exposed in plastic buckets (Fig. 2b). Undoubtedly, this exposure would facilitate the colonization of microorganisms for the fermentation process (Fig. 2c). Peeled fruits, slightly crushed by hand, are placed inside the clay pots in the evening every day (around 18:00 to 20:00 h), then the fruits are left to ferment in clay pot (Fig. 2d). As a safety practice, hands must be dried and cleaned without soap as the water and soap contaminate the colonche. The fermentation of colonche will be described in more detailed in the following section.
During the fermentation, clay pots are placed outdoors and covered with a thin cloth (Fig. 2e). Sometimes, clay pots are placed inside their homes during the night in order to maintain a constant temperature. If raining, clay pots are covered and moved to dry places. After the fermentation is completed, the seeds are removed with a sieve and colonche is freshly served. Colonche is stored in plastic buckets inside producer households and locally distributed (Fig. 2f). Part of the colonche batch that is not consumed fresh can be stored in plastic bottles and may include a mixture of several items as 2 L of colonche for 1 L of alcohol, pineapple, cinnamon, raisins, and anise. This mixture can be saved for multiple years or sold as “vino de tuna” or cactus prickly pear wine. Cactus prickly pear wine is a way to enjoy colonche during the part of the year when fresh colonche is no longer available. But, it should be mentioned that the process to make the “vino de tuna” significantly changes many sensorial attributes in comparison to fresh colonche.
In contrast to the Altiplano region, producers from MC invest more time and resources for colonche production, and this process varies among localities. Outside the center of MC, producers boil the fruit juice three times during the preparation process, while the producers in the center of MC only boil the cactus prickly pear fruits one time. Additionally, in this region, prickly pear fruits from different cactus species are included in the mixture (Fig. 3a). Boiling is performed in metallic drums (Fig. 3e), and wooden tools are used to stir the fruit juice while boiling occurs. We recorded that the same wooden tools have been used for colonche production through several generations (80 ± 30 years) (Fig. 3f). Cooking time is not standardized and depends mainly on observations and criteria of the person preparing the product. Boling is performed over a fire from dried agaves and Opuntias (Fig. 3c).
The first boiling step allows for the separation of the prickly pear pulp and seeds. The seeds are then removed with a sieve (this is a key step because if seeds are present for the second boiling the product will have a smoky flavor). In a second boiling step, spices are added to give the final product the desired flavor profile. The most common spices used are Cinnamomum sp. and Pimpinella anisum. After boiling, the juice is filtered to remove the remains of the spices (Fig. 3d). The final boiling step is performed in order to concentrate the sugars. The juice resulting from the final boiling is called “la miel de la tuna” which means the honey from cactus prickly pear fruits. Finally, this concentrated juice can be stored in the fridge in plastic bottles or placed at the clay pot in order to begin the fermentation process (Fig. 3b). It is important to highlight that pulque is commonly used as a starter for colonche fermentation, and this is indeed added to start the fermentation in the concentrated juice.
In the Tehuacán Valley, during the process of separating prickly pear seeds from the pulp, the fruit juice is collected in buckets or clay pots while seeds are rinsed with water and sun-dried. The fruit juice is stored in clay pots and covered, as all cases documented in this study. Then, a small amount of colonche from a previously prepared batch is added as inoculum of fermentation for the new colonche batch. Fermentation is carried out in dark cool rooms and the new colonche batch is ready to drink two or four days later. The fruit production season of columnar cacti is relatively long (3 to 4 months), and colonche may be prepared several times during this season. Seeds of cardón fruits are stored in dry places, packaged, and taken to the regional markets to be sold. People of the Tehuacán-Cuicatlán Valley highly value cardón seeds and typically combine them with chili peppers and green or red tomatoes to make sauces. Also, these seeds can be ground to a butter-like paste used for preparing several dishes, and it may be stored in the fridge to be used throughout the year (Fig. 4).
Traditional fermentation microorganism’s management
In all the cases studied, the fermentation of colonche occurs within clay plots. In most cases, the clay pot is a part of the household’s cultural heritage and is dated to about 80 years old or older. These pots are not glazed and, when cactus prickly pears fruits are not available, are primarily used for pulque production. Therefore, a layer of microorganisms might always be present in these clay pots. Producers point out that they prefer to produce the fermentation in clay pots rather than plastic or metallic containers because clay pots improve the flavor of the final product. Most of the fermentation occurs at room temperature (about 25 °C to 30 °C).
Fermentation at LG occurs mainly by “spontaneous” fermentation. However, in one case, an experienced colonche producer prepares the first batch of colonche and then shares what is left of this batch to other producers as an inoculated strain known as “zinaiste” or “xinaiste” which guarantees a successful fermentation. The fermentation process lasts for 12 h in LG and 4 h in MC. Fermentation of prickly pear juice in MC starts with the addition of pulque from Agave salmiana. Therefore, in this locality, each producer creates their own xinaiste or inoculum. Pulque is added only to the first batch, the relationship is 15 L of concentrated juice and l L of over-pulque, which is called “pulque fuerte” by local people. The xinaiste could be stored in a fridge or added to new batches. The fermentation in MC (4 h) is shorter than in LG (12 h) and could be due to the addition of the microbial community associated with the xinaiste or pulque.
As mentioned above, in the Altiplano localities, water is thought of as a contaminate of colonche, therefore, clay pots and other utensils used for colonche production most be completely dry. In other studies show that water modifies the composition and the dynamics of microorganism’s communities in the fermentation process and can favor the production of acids [39]. Consequently, adding water to the colonche could bring undesirable flavors, modify the color of colonche from purple to brown and acidify the beverage. Careful strategies are carried out in order to store colonche without water. Cleaning occurs at the beginning and end of the season and is performed with only rinsing clay pots with water then sun drying (soap is not used because it has been observed to give a bad taste to the following batches). At the beginning of the season, most of the producers (80%) clean the clay pots with water and then dry them in direct sunlight. Other producers clean the pot with pulque or with a previously stored xinaiste and only 2% of the producers add alcohol to the clay pots and light a match inside the clay pot using fire as a cleaning method.
When colonche availability declines, different strategies are employed to enjoy colonche for an extended period of time. For instance, in LG, colonche can be stored in glass bottles with the addition of alcohol and dried fruits. Producers in MC stored colonche in the fridge at − 4 °C. This method is similarly used in the villages of the Tehuacán Valley where it may be stored in refrigeration and at the end of the season it is commonly kept in the freezer in plastic bags or bottles.
Selection of colonche desirable flavors
As mentioned above, the microbial community of each beverage plays a significant role in shaping flavor attributes (texture, acidity, etc.). These characteristics are selected by the producers and are modified by their practices and processes during the production of the colonche. An evaluation of the sensorial attributes was conducted by ranking from the most important to the less important, respectively. In order to visualize differences between localities, a PCA scatterplot contrasted a priori groups. The results can be visualized in Fig. 5, with the attributes selected by colonche producers from the Altiplano region and the localities. The first axis represents 34.47% of the variance while the second axis represents 20.22% for a total of 54.69% cumulative variance. The attributes of the first principle component (PC1) are sweetness and alcoholic content which apparently generate the highest variance, meanwhile, the attributes of the second principal component (PC2) are color and acidity which seem to explain the rest of variance observed. Clearly, this PCA allows us to separate localities preferences which might be reflected by the differences in their fermentation practices between localities. Particularly, colonche in LG is a sweet beverage with higher alcohol content. On the other hand, MC colonche is favored to have more complex sensorial attributes.
These results give us a glimpse of which microorganisms may be favored under the fermentation of colonche. This work does not directly compare the microbiota in different regions or localities. Further exploration should examine the composition and the structure of the microbiota involved in fermentation in combination with the differences of substrates.