Abstract:The effect of the dose rate of electron beam irradiation on the quality of vacuum-packaged chilled fresh beef was studied, providing a theoretical basis for the application of electron beam irradiation to the preservation of chilled fresh meat. Vacuum-packaged chilled fresh beef was treated with a 2-kGy irradiation dose at a dose rate of 0, 700, 1500, 2500, or 3500 Gy/s and stored in a refrigerator at 2°C for 15 days. During the storage period, physicochemical indicators (i.e., total volatile basic nitrogen (TVB- N) content, peroxide value (POV), thiobarbituric acid-reactive substances (TBARS), sulfhydryl (SH) groups, disulfide bonds (SS), lightness L*, and redness a*) and a microbiological indicator (total bacterial count (TBC)) of quality were estimated, and the impacts of various dose rates on the effect of irradiation were compared. For a dose of 2 kGy, increasing the dose rate resulted in significantly reduced values of TBC, TVB-N, TBARS, POV, SS, and L*, but increased values of SH and a* (p < 0.05). After 15 days of storage, the treatment group (irradiated with a dose of 2 kGy and a dose rate of 2500 Gy/s) exhibited TBC, TVB-N, POV, TBARS, SH, SS, L*, and a* values of 5.161 colony-forming units (CFU)/g, 16.6 mg/100 g, 1.126 meq/kg, 0.218 mg/100 g, 0.395 mmol/g pro, 0.379 mmol/g pro, 40.34, and 19.57, respectively, representing the optimal irradiation effects.
