Effect of Irradiation Sterilization on Flavor and Physicochemical Properties of Low-salt Sliced Bacon

The effect of irradiation sterilization on the quality of low-salt sliced bacon was investigated by subjecting the samples to high-energy electron gas pedal treatment at 2, 3 and 4 kGy at room temperature. The samples were stored at 4 ℃ and the unsterilized group was used as the control group. The total number of colonies of the samples, flavor substances and the physicochemical indexes were determined when the storage time was 0, 60, 120 and 180 days, respectively. The results showed that the nitrite content of low-salt sliced bacon decreased significantly (P<0.05), the a^* and peroxide value (POV) values increased with the increase of irradiation dose under the same conditions. At 180 d, the moisture content and b^* values of the irradiated group were significantly higher than those of the control group (P<0.05), the L^* and a^* values were not significantly different from those of the control group (P>0.05), and the POV values were significantly lower than those of the control group (P<0.05). During the storage stage, the total bacterial colony values of the irradiated group increased slowly and were always lower than those of the control group, and the content of unpleasant substances such as dimethyl disulfide increased, and the flavor differences with the control group increased, resulting in a decrease in aroma scores. The experimental results of gas chromatography-mass spectrometry (GC-MS) and electronic nose showed that the irradiated off-flavors decreased with the increase of storage time, the content of major flavor substances increased, and the flavor differences with the control group decreased. Overall, 2, 3 kGy-treated bacon samples had lower fat oxidation and the flavor difference between irradiated and control was smaller and the off-flavor was relatively weak. The moisture content was higher and the flavor was better after storage. However, in terms of bactericidal effect and texture, the 3 kGy group was slightly better than the 2 kGy group, with stronger bactericidal effect and slightly higher tissue structure score. Therefore the optimal irradiation was determined to be 3 kGy in this study.