title: 2-alkylcyclobutanones as irradiation dose indicators in irradiated ground beef patties.
abstract: Alkylcyclobutanones have been recognized as chemical markers of irradiated lipid-containing foods since 1970. They are important because they are produced solely as a result of irradiation and not any other processing method. This study investigated the formation of 2-dodecylcyclobutanone (2-DCB) and 2-tetradec-5'-enylcyclobutanone (2-TDCB) in irradiated ground beef patties from commercial and noncommercial sources. Patties were irradiated using a (60)C source (gamma-irradiation) and electron beam irradiation, at five targeted absorbed doses of 0.5, 1.0, 2.5, 5.0, and 7.0 kGy. Commercially available irradiated patties were also studied. A supercritical fluid extraction (SFE) procedure was optimized and used for the extraction and isolation of the alkylcyclobutanones. Samples can be used for extraction without a prior cleanup step, which makes this procedure rapid and convenient to use. Identification and quantitation of the cyclobutanones were done by gas chromatography-mass spectroscopy. 2-DCB was detected in all of the irradiated samples (including commercial patties), and its concentration increased linearly with the irradiation dose. Electron beam irradiation produced a greater amount of 2-DCB compared to gamma-irradiation at dose levels >2.5 kGy. 2-TDCB was detected only at the two higher irradiation doses, whereas both marker compounds were not detected in the non-irradiated samples.
authors.affiliation: The Food Science Institute, Kansas State University, Manhattan 66506, USA.
authors.forename: Priyadarshini
authors.initials: P
authors.lastname: Gadgil
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Hachmeister
authors.forename: J Scott
authors.initials: JS
authors.lastname: Smith
authors.forename: Donald H
authors.initials: DH
authors.lastname: Kropf
mesh_terms: D000818:Animals; D002417:Cattle; D025924:Chromatography, Supercritical Fluid; D003037:Cobalt Radioisotopes; D003503:Cyclobutanes / Q000032:analysis*; D004307:Dose-Response Relationship, Radiation; D005227:Fatty Acids / Q000032:analysis; D005514:Food Irradiation; D005720:Gamma Rays; D008401:Gas Chromatography-Mass Spectrometry; D008460:Meat / Q000032:analysis*
chemical_list: C467423:2-tetradec-5'-enylcyclobutanone; D003037:Cobalt Radioisotopes; D003503:Cyclobutanes; D005227:Fatty Acids; C063381:2-dodecylcyclobutanone