Allium chemistry: Use of new instrumental techniques to “see” reactive organosulfur species formed upon crushing garlic and onion

Three different instrumental methods have been used to examine the organosulfur chemistry of intact and cut garlic and onions: X-ray fluorescence spectroscopic imaging (XFS), direct analysis in real time (DART) mass spec-trometry, and ultra-performance liquid chromatography-(Ag + )-coordination ion spray mass spectrometry (UPLC–(Ag + )CIS–MS). The first technique has been used to map the location of different chemical forms of sulfur in intact and damaged onion cells, the second technique, to identify the reactive, volatile sulfur compounds formed on cutting the plants, and the third technique, to identify members of families of polysulfides found in the distilled oil of garlic.