P201: Bev-O-Metrics: An NMR analysis of beverages for caffeine
The concepts and application of Nuclear Magnetic Resonance (NMR) spectroscopy pose a challenge to many students. We describe here our experiments involving caffeine analysis that can be used not only as an educational tool to introduce NMR to students but which can also lead to new findings on caffeine levels in common and readily available beverages. Through the experiment the reasons behind chemical shift and how NMR is used become apparent. Our method generates a standard or calibration graph for the caffeine from beverages that shows good correspondence to the graph from a standard using pure caffeine. The standard graph can then be used to determine the (previously unknown) caffeine content of other beverages. The links between bitterness of caffeine and salt content (that is opaque to NMR) may also be demonstrated. This talk may include a coffee or beverage tasting.