8-heptadecene and dimethyl-disulfide

Raw and cooked beef and pork loins were irradiated at 0 or 5 kGy. The radiation-induced marker compounds, such as hydrocarbons, 2-alkylcyclobutanones (2-ACBs), and sulfur volatiles, were determined after 0 and 6 mo of frozen storage. Two hydrocarbons (8-heptadecene [C(17:1)] and 6,9-heptadecadiene [C(17:2)]) and two 2-ACBs (2-dodecylcyclobutanone [2-DCB] and 2-tetradecylcyclobutanone [2-TCB]) were detected only in irradiated raw and cooked meats. Although precooked irradiated meats produced more hydrocarbons and 2-ACBs than the irradiated cooked ones, the amounts of individual hydrocarbons and 2-ACBs, such as 8-heptadecene, 6,9-heptadecadiene, 2-DCB, and 2-TCB, were sufficient enough to detect whether the meat was irradiated or not. Dimethyl disulfide and dimethyl trisulfide were also determined only in irradiated meats but dimethyl trisulfide disappeared after 6 mo of frozen storage under oxygen-permeable packaging conditions. The results indicated that 8-heptadecene, 6,9-heptadecadiene, 2-DCB, 2-TCB, and dimethyl disulfide, even though they were decreased with storage, could be used as marker compounds for the detection of irradiated beef and pork regardless of cooking under the frozen conditions for 6 mo.. Radiation-induced chemical changes such as specific hydrocarbons, 2-ACBs, and sulfur volatiles may be used as potential identification markers by regulatory authorities to confirm irradiation history of frozen stored raw or cooked beef and pork.

Topics: Alkenes; Animals; Cattle; Cooking; Cyclobutanes; Disulfides; Food Irradiation; Food Storage; Freezing; Hydrocarbons; Meat; Odorants; Swine; Taste; Volatile Organic Compounds

To determine the effects of irradiation on the chemical attributes of sausages, TBARS values, volatile compounds, gaseous compounds, and hydrocarbons of vacuum-packaged sausages were analyzed during 60 d of refrigerated storage. A sulfur-containing volatile (dimethyl disulfide), a gas (methane), and radiation-induced hydrocarbons (1-tetradecene, pentadecane, heptadecane, 8-heptadecene, eicosane, 1, 7-hexadecadiene, hexadecane) were mainly detected in irradiated sausages and the concentrations of these compounds were irradiation dose-dependent with R(2) = 0.9585, 0.9431, and 0.9091-0.9977, respectively. Especially methane and a few hydrocarbons were detected only in irradiated sausages and their amounts were dose-dependent. On the other hand, TBARS values, other off-odor volatiles (carbon disulfide, hexanal), and gases (carbon monoxide, carbon dioxide) were found both in irradiated and nonirradiated sausages. Therefore, it is suggested that radiation-induced hydrocarbons (1-tetradecene, pentadecane, heptadecane, 8-heptadecene, eicosane, 1, 7-hexadecadiene, hexadecane), dimethyl disulfide, and methane can be used as markers for irradiated sausages.

Topics: Aldehydes; Alkanes; Alkenes; Animals; Chemical Phenomena; Disulfides; Food Irradiation; Hydrocarbons; Lipid Peroxidation; Meat Products; Odorants; Swine; Thiobarbituric Acid Reactive Substances; Turkeys; Volatile Organic Compounds; Volatilization