Quantitation of Polysulfides in Wine, Beer, and Cider by HPLC-MS/MS after Solid-Phase Extraction

Polysulfides are chain-like organosulfur compounds that are recognized as potential reservoirs of volatile sulfur compounds (VSCs) in wine. Quantitative analysis of polysulfides is essential for understanding their relationship with VSCs, so an approach using solid-phase extraction and high-performance liquid chromatography with tandem mass spectrometry was developed, utilizing glutathione di- and trisulfide standards. Quantitation of di- and polysulfides in commercial wine, beer, and cider was then undertaken. Four disulfides were consistently confirmed in beer and wine but were close to the detection limit in ciders. Long-chain polysulfides were detected predominantly in wine samples, with red wines containing higher levels of di- and trisulfides compared to white wines. There was a distinct association between wine parameters of SO2 and pH with the measured sulfur compounds. Principal component analysis revealed some clustering by wine variety, although vintage and region effects were less distinct, highlighting the complex interactions among the factors influencing polysulfide profiles in wine.