Rapid Quantification of Ethyl Carbamate in Spirits Using NMR Spectroscopy and Chemometrics

Ethyl carbamate (EC, urethane, C2H5OCONH2) is a genotoxic carcinogen and is regularly found in fermented food products including alcoholic beverages. In this study, the rapid method of nuclear magnetic resonance (NMR) spectroscopy in combination with partial least squares (PLS) regression is applied for the first time to the analysis of ethyl carbamate in stone fruit spirits ( = 119) and unrecorded alcohols ( = 27) (analysis time only 15 min per sample). The PLS procedure was validated using an independent set of samples ( = 43, 2= 0.89, RMSE = 0.14 mg/L) in comparison to reference GC/MS/MS results. The NMR method was found to outperform other screening techniques based on NIR or FTIR regarding sensitivity and selectivity. The major advantage over GC/MS/MS, besides the reduced time of instrumental analysis, is that no sample preparation besides addition of buffer with internal standard is required, while for GC/MS/MS labour-intensive sample extraction is necessary prior to measurement