UPLC-HRMS for discriminant metabolomic studies of tequila

Abstract

Tequila is a distilled beverage with denomination of origin, protected by law, and with a great economic importance. Mexican regulation specifies the categories, classes, and production regions of Tequila. Metabolomics is used to measure the concentrations of individual metabolites in distilled spirits to assess authenticity. For this study 27 commercial brands of Tequila were analyzed by UPLC-MS-ESI. From the total of Tequila samples, five corresponding to tequilas; and twenty-two to 100% agave (according to category); ten corresponding to Silver, ten to Aged, six to Extra-aged, and one to Ultra-aged (according to class); thirteen to Los Altos, Jalisco, and fourteen to Tequila, Jalisco. The samples were analyzed without preparation. The metabolomic method was used to discriminate Tequila by category, class, and geographic origin. The samples were ionized in negative and positive mode. The compounds obtained in negative mode were 104 and in positive 123. The ANOVA showed that the significant compounds in negative mode were 32 according to the category, 79 according to the class, and 36 according to the origin; in positive mode 42 according to the category, 94 according to the class, and 48 according to origin. General Discriminant Analysis were used to separate Tequila’s classification by the Mahalanobis distances.