Isotopic ratios of δ13CVPDB and δ18OVSMOW have been used as an additional parameter to ensure the authenticity of the aging time of 100% agave tequila. For this purpose, 120 samples were isotopically analyzed (40 silver class, 40 aged class, and 40 extra-aged classes). The samples were obtained through a stratified sampling by proportional allocation, considering tequila producers from the main different regions of Jalisco, Mexico (Valles 41%, Altos Sur 31%, Cienega 16%, and Centro 12%). The results showed that the δ13CVPDB was found in an average of −12.85 ‰ for all the analyzed beverages, with no significant difference between them. Since for all the tested samples the Agave tequilana Weber blue variety was used as source of sugar to obtain alcohol, those results were foreseeable, and confirm the origin of the sugar source. Instead, the results for δ18OVSMOW showed a positive slope linear trend for the aging time (silver class 19.52‰, aged class 20.54‰, extra-aged class 21.45‰), which is associated with the maturation process, there are oxidation reactions that add congeneric compounds to the beverage, these can be used as tracers for the authenticity of the aging time. Additionally, the experimental data showed homogeneity in the beverages regardless of the production region, evidencing the tequila industry’s high-quality standards. However, a particular case occurs with the δ18OVSMOW data for the silver class samples, in which a clear trend is noted with the altitude of the region of origin; therefore, this information suggests that this analytical parameter could be useful to authenticate the regional origin of beverage.

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Due to the oversupply and scarcity cycles of the Agave tequilana Weber blue variety, the effect of agave age (harvested in 4, 5, and 6 years) as raw material for the tequila 100% agave silver class was studied for each stage in a full-scale (industrial) process. Harvested plants showed differences in their morphological characteristics that affected the amount of juice; this had an impact in the fermentation stage since must composition was modified in the nitrogen content and juice/exudate ratio. This was noticed due to an increase in the production of higher alcohols attributed to the odd-chain fatty of the exudate, which affects n-propanol production. The characterization of the final product showed the feasibility to use agaves (less than 7 years) to produce the Tequila 100% agave silver class and to comply with the quality criteria. Furthermore, the final product was analyzed with the gas chromatography-isotope ratio mass-spectrometry technique to determine its authenticity. The δ13CVPDB isotopic parameter (−13.40‰ in average) values show the type of plant used as a raw material for ethanol production, while the δ18OVSMOW (20.52‰ in average) isotopic parameter can be helpful in corroborating and ensuring the traceability of the product and the geographical location of the beverage production.

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