Food Science & Safety

NMR effectively discriminates artisanal beers

“…our results suggest the strength of 1H NMR spectroscopy combined with chemometric tools for the analysis of beer and the discrimination of different production procedures and product features”

The craft brewing industry is rapidly expanding and already accounts for 98% of all breweries in the U.S. The immense popularity of craft beers due to the extensive selection of styles and tastes combined with their unique character has made them increasingly popular with beer-drinking consumers. The premium cost associated with these beers, however, has made them a target for fraud. Consequently, there has been much research into identifying an effective tool for confirming the authenticity of craft beers on the market.

With the unique nature of a craft beer arising from a combination of the area in which the cereal malt and hops were grown and the blend of local spices that have been added, metabolomic analysis to uncover the signature profiles of individual beers seemed a promising option. Indeed, nuclear magnetic resonance spectroscopy (NMR) has demonstrated the capacity to successfully discriminate beers according to their age, fermentation process, and origin.

Recent research used NMR metabolomic analysis to characterize a selection of craft beers by their metabolic profiles and use these as a means to discriminate them from industrially produced beers. 1HNMR using a Bruker AVANCE III 600 MHz NMR spectrometer equipped with a QCI cryogenic probe was applied to samples of fourteen industrial beers and seventeen craft beers of different styles and country of origin.  The spectra obtained were then evaluated using both untargeted and a targeted multivariate statistical analysis.

The metabolic profiles of artisanal and industrial beers were found to be distinct. Craft beers had lower concentrations of adenosine/inosine and trehalose, and higher levels of asparagine, trigonelline, lactate, acetate, and succinate compared with industrially produced beers. The craft beer could thus be readily discriminated from industrial beer by quantification of the specific small molecules present.

The spectra obtained from the beer samples were subsequently used to create NMR libraries for the Simple Mixture Analysis (SMA) tool to enable more rapid beer characterization.

This research has confirmed the potential of 1H NMR spectroscopy as an analytical tool for determining the authenticity of craft beers. Indeed, it is hoped that these new data will inform the development of a standardized protocol for the discrimination of industrial and craft beers.

Palmioli A, et al.  Metabolomic profiling of beers: Combining 1H NMR spectroscopy and chemometric approaches to discriminate craft and industrial products. Food Chemistry 2020;327:127025. https://doi.org/10.1016/j.foodchem.2020.127025