Abstract:

For the analysis of organosulfur compounds in fresh garlic, a gas chromatographic/mass
spectrometric （GC/MS） method is proposed using temperature-programmable cold on-column injection
and cold solvent extraction of the fresh garlic. This was carried out under the conditions of
cryogenic process from extraction to column separation. Hence, a valid identification can be
achieved about the primary components in garlic extract before thermo-degradation. The obtained
results showed that 3-vinyl-4H-1,2-dithiin and 2-vinyl-4H-1,3-dithiin were the major compounds in
the garlic extract with minor amounts of S-methyl methanethiosulfinate, diallyl disulfide,
trisulfide-di-2-propenyl. A comparative study of chemical compounds was performed between garlic
extract by cold solvent and garlic oil by stream distillation. The degradation and formation of
major organosulfur compounds in the garlic extract were also explored.

Key words: cold on-column, garlic , organosulfur compounds, temperature-programmable
inlet, gas chromatography/mass spectrometry （GC/MS）