A sulfur off-odor was reported in specific lots of diet cola. The client was unable to successfully identify the chemical nature of the odorant and samples were sent to VAC for further analysis. Upon receipt at the VAC lab, sulfur odor was noticeable upon simple organoleptic analysis of the diet cola. A series of extraction methods (coupled with GCMS analysis) proved unsuccessful including long term SPME fiber and SBSE exposure to liquid sample, and liquid sample headspace. A dynamic device that trapped volatiles in thermal desorption tubes sealed and immersed in 1 oC water bath proved successful at identifying the odorous component as dimethyl sulfide.