Analysis of irradiated cooked ham by direct introduction into the programmable temperature vaporizer of a multidimensional gas chromatography system

A simple method involving direct introduction (DI) of cooked ham into a programmable temperature vaporizer and subsequent thermal desorption for multidimensional chromatographic analysis as a tool for studying changes of volatile compounds during food irradiation has been proposed. Analysis of non-irradiated samples showed four peaks in the precolumn, which were identified on the main column as peak 1, ethyl acetate; peak 2, a mixture of octanol and ethyl propanoate; peak 3, (R,R)-2,3-butanediol, and peak 4, nonanoic acid. (R,R) and (S,S)-2,3-butanediol were detected in samples irradiated at 8 kGy, which may indicate that irradiation induces isomerisation. When a single cut was transferred from the precolumn to the main column, 1-tetradecene, n-pentadecane, 8-heptadecene and 1-hexadecene were detected in irradiated samples. This simple and easy method allows detection of radiolytic markers and isomerisation of 2,3-butanediol during irradiation of food.