Usage of FT-ICR-MS Metabolomics for Characterizing the Chemical Signatures of Barrel-Aged Whisky

Abstract

Whisky can be described as a complex matrix integrating the chemical history from the fermented cereals, the wooden barrels, the specific distillery processes, aging, and environmental factors. In this study, using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) and liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), we analyzed 150 whisky samples from 49 different distilleries, 7 countries, and ranging from 1 day new make spirit to 43 years of maturation with different types of barrel. Chemometrics revealed the unexpected impact of the wood history on the distillate's composition during barrel aging, regardless of the whisky origin. Flavonols, oligolignols, and fatty acids are examples of important chemical signatures for Bourbon casks, whereas a high number of polyphenol glycosides, including for instance quercetin-glucuronide or myricetin-glucoside as potential candidates, and carbohydrates would discriminate Sherry casks. However, the comparison of barrel aged rums and whiskies revealed specific signatures, highlighting the importance of the initial composition of the distillate and the distillery processes.

Metabolic profiling of different wild and cultivated Allium species based on high‐resolution mass spectrometry, high‐performance liquid chromatography‐photodiode array detector, and color analysis

“…A variety of metabolites assayed by CID-MS n (n = 2,3) experiments allowed to achieve orthogonal information with accurate mass determination, so to distinguish among candidate isomeric species (Table S1) Forthcoming work will be devoted to apply the analytical approach to a wider set of samples to afford a statistical analysis of potentially predictive and diagnostic purpose. 31,[57][58][59] Although…”

“…This method has widely demonstrated to be a powerful tool for characterizing the polar fraction of a variety of complex matrices such as foodstuff and essential oils. [29][30][31][32][33][34][35] Visualization of the so-obtained chemical profiles by van Krevelen diagrams affords a plain screening approach for the different Allium samples.…”

Quantification of whisky congeners by 1H NMR spectroscopy

“…Despite whisky containing thousands of compounds, as established by FT ICR MS, 24‐27 1 H NMR spectra show signals of only a few dozen compounds. This is due to very different detection limits of the two techniques and can be viewed as a curse (loss of information) but also a blessing (possibility to quantify a limited number of the most concentrated compounds) by NMR.…”

Soil properties and biochemical composition of ground‐dwelling bee nests in agricultural settings

“…Recent advances in ultrahigh‐resolution analytical techniques, FTICR‐MS in particular, have provided novel insights into the molecular composition of dissolved organic matter in fresh and marine water (Hertkorn, Harir, Koch, Michalke, & Schmitt‐Kopplin, 2013; Lu et al., 2015; Sleighter et al., 2007; Tfaily et al., 2018a), SOM in different terrestrial systems (Bhattacharyya et al., 2018; Choi et al., 2017; Tfaily et al., 2018b), and the metabolic content of plant root exudates (Pollier, Morreel, Geelen, & Goossens, 2011) and whisky (Roullier‐Gall et al., 2018). Here, for the first time, we apply the capabilities of FTICR‐MS to the analysis of soils lining active bee nesting sites to detect and identify molecular compounds possibly secreted by wild bees and sand wasps in field settings (Figures 2, 6–8).…”