Abstract: In the present study, pork sausages were irradiated by 60Co γ-ray ray at doses of 1, 3, 5, 7 and 9 kGy, respectively. After that, the off-flavor intensity, lipid oxidation, volatile flavor composition and color difference of sausages were determined for the purpose of evaluating the effect of irradiation on the physicochemical and sensory quality of pork sausages. The results indicated that irradiation could significantly promote lipid oxidation and result in a decrease in the redness value (a*) of pork sausages, but the yellowness (b*) and lightness (L*) values were not affected by irradiation. The off-flavor intensity increased with increasing irradiation dose, but it did not change significantly within the dose range of 1–5 kGy; when the irradiation dose was increased to 7 kGy, pork sausages produced a significantly unacceptable off-flavor. The contents of volatile sulfur-containing compounds, 2-butene, pentane, 1-pentene, octane, hexane and aldehydes increased significantly compared to the control samples, which were positively correlated with irradiation dose. Carbon disulfide, dimethyl disulfide, 2-methyl-propanal, 3-methyl-butanal, hexanal, butene and toluene were the main volatiles that were generated after irradiation. These results suggested that the irradiation could deteriorate the flavor and color of pork sausage, especially at a dose above 5 kGy. These quality changes were closely related with lipid oxidation of pork sausages.

Key words: radiation, lipid oxidation, volatile flavor, color