Evaluation of low-field versus high-field proton NMR spectroscopy for quality control of cinnamon samples

Abstract

The use of cinnamon as a spice for cooking or as a dietary supplement for its nutraceutical properties is widespread around the world. In this study, 28 samples, 14 cooking spices and 14 dietary supplements, were analysed using both high-field (400 MHz) and low-field (60 MHz) NMR. High-field NMR analysis was performed for profiling, quantitative analysis and classification of the samples between Ceylon cinnamon and cassia cinnamon. Then, the capabilities and limitations of low-field NMR for quality control of cinnamon were studied and discussed. At last, the chemometric treatment of low-field NMR spectra has proved to be an interesting way of predicting quantification of their contents in coumarin and (E)-cinnamaldehyde. For dietary supplements, this approach allowed to identify samples containing a higher quantity of hepatotoxic coumarin and thus presenting a potential risk to the health of consumers.