Duncan Cameron (1), Mark Burrell (1), Lee Eales (1), Robert Falconer (1), Jacob Nickles (2); (1) University of Sheffield, Sheffield, U.K.; (2) Mettle Leisure Ltd and University of Sheffield, Sheffield, U.K.
Over the past two decades, rapid advances in analytical chemistry, specifically in mass spectrometry has provided an ever-deeper understanding of the chemistry of beer in relation a range of factors such as storage, brewing processes and hop varieties used. Concurrently, the field of metabolomics, “the systematic study of the unique chemical fingerprints that specific cellular processes leave behind,” has been used to study the responses of organisms to external factors at the small-molecule scale. Increasing numbers of studies claim to deploy metabolomics in the context of beer; few, however, do so in a truly untargeted fashion that allows the emergent properties of beer chemistry to be profiled. This is because either the analytical technique or the resultant bioinformatics approaches used are targeted at one level or another. Moreover, the sample preparation and throughput of the analytical methodology makes analysis lengthy and expensive, limiting its widespread application. Here, we couple high-throughput, low-cost untargeted biochemical fingerprinting of beers using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSi) on a diverse selection of styles of beers obtained from several breweries in the United Kingdom to unsupervised and supervised dimensional reduction statistical analysis approaches (PCA and O2PLS-DA, respectively). For proof of concept, we resolve the principal differences in the chemistry of different batches of the same beer and different beers from different breweries in relation to the orthogonal variables of color and brewery identity to understand the chemical similarity of similarly styled beers, along with their biochemical consistency across batches. In conclusion, we validate the MALDI-MSi approach as a high-throughput, low-cost method for profiling beer chemistry and are currently developing the methodology for wide-scale application.
Duncan Cameron is an environmental biochemist and chair of plant and soil biology at the University of Sheffield, where he also holds a prestigious Royal Society University Research Fellowship. Duncan leads an international group using integrated “omics” technologies (genomics, proteomics and metabolomics) to study the biological chemistry of soils, as well as physiology and chemistry of plants and microbes. After receiving his B.S. degree in zoology and botany from the University of Sheffield and his Ph.D. degree in plant and soil sciences from the University of Aberdeen, Duncan undertook postdoctoral research in Sheffield and at the Julius von Sachs Institute at the University of Wurzburg, Germany. Duncan previously held a NERC Personal Research Fellowship, also at Sheffield, prior to taking up his current position. Duncan currently is subject editor of Plant and Soil, member of the editorial board of Food and Energy Security, as well as a member of the Royal Society International Committee, member of the Natural Environment Research Council’s peer-review college and a panel member for the Biology and Biotechnology Research Council. In 2013, he chaired the Royal Society Frontiers of Science meeting, Beijing, China, and in the same year received the World Economic Forum’s “40 under 40” Young Scientist Award for his work in translating fundamental advances in plant science into practical agricultural solutions.