Ethyl carbamate analysis in german fruit spirits and brazilian sugarcane spirits (cachaça): improved sample cleanup with automated parallel evaporation

Abstract

The analysis of alcoholic beverages for the important carcinogenic con-taminant ethyl carbamate is very time-consuming and expensive. Due to possible matrix interferences, sample cleanup using diatomaceous earth (Extrelut) columns is required prior to gas chromatographic and mass spectrometric measurement. A limiting step in this process is the rotary evaporation of the eluate containing the analyte in organic solvents, which is currently conducted manually and requires approximately 20-30 min per sample. This paper introduces the use of a parallel evaporation device for ethyl carbamate analysis, which allows for the simultaneous evaporation of 12 samples to a specified residual volume without manual intervention. A more efficient and less expensive analy-sis is therefore possible. The method validation showed no differences between the fully-automated parallel evaporation and the manual opera-tion. The applicability was proven by analyzing authentic spirit samples from Germany, Canada and Brazil. It is interesting to note that Brazilian cachaças had a relatively high incidence for ethyl carbamate contamina-tion (55 % of all samples were above 0.15 mg/l), which may be of public health relevance and requires further evaluation.