Optimization of Determination of Dimethyl Sulfi de in Wort and Beer

Abstract

Sulphur compounds present in barley, malt and beer are mostly non-volatile substances (amino acids, proteins, inorganic sulphates) from which volatile sensory active substances can be produced under certain conditions. The presence of these substances in beer can adversely affect its organoleptic properties. Dimethyl sulfi de (DMS) is one of the most studied volatile sulphur compounds in beer; therefore a suitable analytical method for monitoring DMS content is necessary. The static headspace method coupled to gas chromatography with fl ame photometric detector (HS-GC-FPD) used for the determination of DMS content in wort and beer was optimized and validated. Optimal yield of HS extraction was achieved after 30 minutes at 50 °C. DMS contents moved from 9.6 to 59.6 μg.l^-1 in the analysed worts, from 6.1 to 34.9 μg.l^-1 in beers.