| The effectiveness of electron beam irradiation in reducing microbial contamination and extending shelf-life in chicken breast fillets was investigated. Because electron beam irradiation can possibly increase lipid oxidation in cooked breast fillets, vacuum packaging was also investigated as a means of minimizing the effects of lipid oxidation on breast fillets. Boneless, skinless chicken breast fillets were subjected to electron beam irradiation doses of 0.8, 1.0, and 1.8 kGy and stored up to 42 days at 4 C. Breast fillets were also packaged and stored in vacuum packaging in an attempt to reduce effects of electron beam irradiation on lipid oxidation in breast fillets. Microbial analyses were conducted to determine population levels of coliforms, generic E. coli, total aerobic bacteria, psychrotrophs, Salmonella , and Campylobacter in the fillets. Color determination, sensory evaluation, and thiobarbituric acid reactive substances (TBARS) were used as parameters to determine the effects of electron beam irradiation on overall quality of breast fillets. Results suggested that even the minimum dose of 0.8 kGy was effective in eliminating coliforms, generic E. coli, Salmonella, and Campylobacter in irradiated samples. Population levels of total aerobic bacteria and psychrotrophs were not completely eliminated, but even the minimum dose of 0.8 kGy resulted in a substantial decrease in population levels. Vacuum packaging had no effect on population levels. All three levels of irradiation resulted in an increase in a* values or redness of the products with vacuum packaged samples having higher a* values. Results from sensory evaluation indicated that increasing levels of irradiation and storage time resulted in less acceptable products. However, fewer TBARS were observed in breast fillets that had been vacuum packaged and then irradiated indicating that less lipid oxidation occurred. As storage time increased, TBARS also increased, but at a lower rate in both non-irradiated and irradiated vacuum packaged breast fillets. |
