Ultra-high-performance liquid chromatography-high-resolution mass spectrometry based metabolomics as a strategy for beer characterization

Abstract

An ultra-high performance liquid chromatography–high resolution mass spectrometry (UHPLC-HRMS) method was applied to the analysis of beers. Chromatographic profiles were recorded in both positive and negative electrospray modes and the resulting data was evaluated according to an untargeted metabolomic approach applied to the discrimination and characterization of beers. Principal components analysis and partial least squares–discriminant analysis were used for exploratory characterization and classification of beers according to the brewing procedure. Results showed that the chemometric models were able to distinguish among beer types. The study of MS features indicated that various detected markers were relevant for beer discrimination. Among them, for example, p-coumaric and ferulic acids, and 5-methylthioadenosine were tentatively identified as characteristic descriptors of Pilsner and Belgian ale beers, respectively. These findings were further confirmed by comparison of the UHPLC-HRMS data with those of standards and/or by MS/MS experiments. Conclusions extracted were validated on an independent set of samples. This work shows the applicability of untargeted metabolomic strategies to the characterization of beers at the molecular level. Copyright © 2016 The Institute of Brewing & Distilling