Double-packaging is effective in reducing lipid oxidation and off-odor volatiles of irradiated raw turkey meat.

The effects of double packaging on lipid oxidation, color, and volatile production were determined to establish a modified packaging method to improve quality changes in irradiated raw turkey meat. Sliced raw turkey breast and thigh meats were aerobically, vacuum- or double (vacuum and aerobic)-packaged, electron beam irradiated at 2.5 kGy, and then stored under refrigerated temperature. For the double-packaged samples, the outer vacuum bags were removed after 5, 7, or 9 d of refrigerated storage. 2-Thiobarbituric acid-reactive substances (TBARS) values, volatile compounds, and color values of the samples were determined after 10 d of storage. Irradiation and aerobic packaging promoted production of aldehydes (propanal and hexanal) related to lipid oxidation in turkey breast and thigh meats. Vacuum-packaged irradiated samples retained S-volatile compounds (methanethiol, dimethyl sulfide, dimethyl disulfide, and dimethyl trisulfide), mainly responsible for the irradiation off-odor, during storage. Exposure of double-packaged irradiated turkey meats to aerobic conditions by removing outer vacuum bags a few days before the test was effective in controlling both lipid oxidation-dependent (aldehydes) and radiolytic off-odor (S-compounds) volatiles. The a* values of raw turkey breast and thigh meats increased by irradiation regardless of packaging conditions. The a* value of double-packaged meats was lower than that of the vacuum-packaged meats but was not significant. Thus, the use of double-packaging alone was not enough to reduce the pink color of irradiated raw turkey meat. When lipid oxidation and irradiation off-odor should be minimized without any additional additives, however, double packaging is an excellent method to be used for turkey meats.