Introducing Undergraduate Students to Metabolomics Using a NMR-Based Analysis of Coffee Beans

Metabolomics applies multivariate statistical analysis to sets of high-resolution spectra taken over a population of biologically derived samples. The objective is to distinguish subpopulations within the overall sample population, and possibly also to identify biomarkers. While metabolomics has become part of the standard analytical toolbox in many areas of chemical research, its principles and methods have not yet been generally incorporated into the undergraduate chemistry curriculum. Identification of the arabica and robusta varieties of green coffee beans using H-1 NMR-based principle component analysis provides an inexpensive teaching laboratory experiment that introduces students to the methods of metabolomics. The experiment does not require any expensive chemicals, or unique equipment or software, or access to higher-field instruments. Because there is a general curiosity among students about the chemical composition of coffee, the experiment is also particularly engaging to the students' interest and imagination.