Preserving Tradition and Promoting Innovation: “Quesillo,” Artisanal Cheese from Oaxaca, Mexico

Resumen

The quesillo is a traditional food originally produced in the state of Oaxaca, Mexico, is fresh, spun paste or strands, made with raw milk and has unique sensory attributes due to its extensive native microbiota, mainly lactic acid bacteria, which are fermenting microorganisms, safe, are used in the fermentation and preservation of food helping to improve flavor, aroma, and texture. They are part of the natural microbiota of raw milk and its derivatives, mainly traditional cheeses, where the greatest diversity and heterogeneity is found. The objective of this study was to microbiologically identify lactic acid bacteria (LABs) present in the traditional quesillo of Oaxaca, Mexico. Quesillo samples were collected in three municipalities in Oaxaca, Mexico. Serial dilutions were prepared from 10 g of sample, then seeded in a Man, Rogosa, and Sharpe (MRS) selective medium. Subsequently, they were incubated at 30 °C for 24 to 48 h. The strains were identified macroscopically and microscopically, catalase and oxidase tests were performed as confirmation tests for LAB. From the three traditional quesillo samples, 86 colonies with BAL macroscopic morphology were identified, strains with yeast morphology, coccobacillary, catalase and oxidase positive were discarded, and finally 56 strains were identified with macroscopic and microscopic characteristics of LAB type, gram positive, bacillary and coccobacillary morphology, catalase and oxidase negative. In conclusion, quesillo is a traditional product that presents lactic acid bacteria as important microorganisms, which, in addition to improving sensory attributes and food preservation, can present probiotic properties that when administered in adequate amounts confer a health benefit to the host.