DETERMINATION OF VOLATILE SULFUR-COMPOUNDS IN WATER SAMPLES, BEER ANDCOFFEE WITH PURGE-AND-TRAP GAS-CHROMATOGRAPHY MICROWAVE-INDUCED PLASMA-ATOMIC EMISSION-SPECTROMETRY

A method for the determination of 13 volatile sulfur compounds includi ng dimethyl sulfide, dimethyl disulfide (DMDS), carbon disulfide and o ther sulfides and thiols in water samples was developed. The analytes were stripped from the sample by a now of helium and preconcentrated i n a capillary cryogenic trap. This was followed by determination by ga s chromatography-microwave-induced plasma atomic emission spectrometry . Detection limits ranged from 8 pg (0.4 ng l(-1)) for ethanethiol to 17 pg (0.9 ng l(-1)) for DMDS. The method was successfully applied to the quantitative analysis of fresh and sea water and after slight modi fications also to different Belgian beer types and coffee powder. A sy stem for the automated sample delivery was developed for liquid sample s.