air-, oven- and freeze-dried garlic bulbs were hydrodistilled and the resulting essential oils were analyzed by gas chromatography (gc) and gc/mass spectrometry (gc/ms). the highest yields were 0.6 and 0.5% (w/w) for freeze- and oven-dried samples, respectively. the essential oils were characterized by a high amount of sulfur compounds (84.3-98.9%) with diallyl trisulfide (37.3-45.9%), diallyl disulfide (17.5-35.6%) and methyl allyl trisulfide (7.7-10.4%) being the major components. remarkable qualitative and quantitative differences between the investigated oils owing to the drying procedure were found and a set of marker components was established to differentiate between them.