Green coffee oil analysis by high-resolution nuclear magnetic resonance spectroscopy

In this work, we show how an extensive and fast quantification of the main components in green coffee oil can be achieved by NMR, with minimal sample manipulation and use of organic solvents. The approach is based on the integration of characteristic NMR signals, selected because of their similar relaxation properties and because they fall in similar spectral regions, which minimizes offset effects. Quantification of glycerides, together with their fatty acid components (oleic, linoleic, linolenic and saturated) and minor species (caffeine, cafestol, kahweol and 16-O-methylcafestol), is achieved in less than 1h making use of 1H and 13C spectroscopy. The compositional data obtained are in reasonable agreement with classical chromatographic analyses. [Display omitted] ► Coffee oil was analyzed by NMR. ► The concentration of main components was quantified. ► The NMR and the chromatographic results are in reasonable agreement. ► These results open several possible applications in the field of coffee analysis.