An apparatus is described, designed to collect and analyze volatiles from canned tuna by gas chromatography. Although tracings from experimental packs of tuna of varying degrees of freshness were distinctly different, only one peak was found to regularly increase with spoilage. Differences, in terms of peak size between organoleptically good, questionable and decomposed samples were statistically significant. The substance represented by the peak was isolated and identified as ethanol. The implications of these findings are discussed.