Irradiated ground beef patties: dose and dose-age estimation by volatile compounds measurement

Volatile compounds produced by irradiation in ground beef patties, packaged under vacuum, were extracted by head-space solid-phase micro-extraction and quantified by gas-chromatography coupled to mass-spectrometry. The study was carried out at levels of irradiation, ranging from 0.5 to 8kGy. Among the 101 detected volatiles compounds, 25 resulted correlated with dose. On the basis of further measurements at 30 and 120 days after irradiation, the most stable compounds with time were identified. To estimate the dose just after irradiation, linear combinations of selections of possible dose markers were obtained via partial least squares regression. A further data analysis showed that it is possible to reconstruct both the irradiation dose and the time elapsed after irradiation from the ratio between the peak areas of some dose markers. The adopted experimental procedure combined with a proper data analysis may lead to dose or dose/age reconstruction in a rapid, simple and efficient way.