Determination of Radiation Induced Hydrocarbons in Irradiated Camembert and Processed Cheese by GC-MS

Food irradiation processing needs proper control to facilitate consumer assurance, choice, and protection, including accurate detection of irradiated food. This study was aimed at analyzing hydrocarbons induced by gamma and electron beam irradiation in Camembert and processed cheeses. The samples were irradiated at 0, 1, 3, 5, 7, and 10 kGy doses of γ-rays and an electron beam. The induced hydrocarbons were separated on a florisil column and identified by gas chromatography-mass spectrometry (GC-MS). The detected hydrocarbons were pentadecane and 1-tetradecene from palmitic acid, heptadecane and 1-hexadecene from stearic acid, and 8-heptadecene and 1,7-hexadecadiene from oleic acid. The concentrations of the radiation-induced hydrocarbons increased with irradiation dose. Among the induced hydrocarbons, 1-tetradecene and 1,7-hexadecadiene were found to be the major hydrocarbons in the cheese samples. For most irradiation doses, the concentration of hydrocarbons induced by the electron beam was slightly higher than by gamma rays. These hydrocarbons were detected only in irradiated samples at 1 kGy or above, and not in the nonirradiated ones. It was concluded that the detected hydrocarbons were good markers to distinguish irradiated and nonirradiated cheese.