Effect of in-bag carcass decontamination method on shelf life of whole chicken carcasses packaged in plastic bags

This study was undertaken to investigate the changes in the microbiological and sensorial attributes of the fresh chicken carcasses that were immersed in decontamination solutions followed by packaging in nylon bags in that decontamination solution was added during storage at 4?C. The experiments were carried out on chilled, chicken carcasses in a commercial slaughterhouse. The treatment groups were control, 1 % lactic acid, 0.1 % cetylpyridinium chloride, and 8 % trisodium phosphate. With the exception of the control group, the carcasses were immersed in the decontamination solution instantaneously followed by packaging in the nylon bag. Then, 15 ml of the same decontamination solution was added into the bag before clipping. The packaged carcasses were stored at 4?C. The samples were taken on days 0, 3, 7, and 10 for microbiological (enumeration of total aerobic mesophilic and psychrophilic microorganisms, coliform bacteria, yeast-mold, and presence of Salmonella spp.) and sensory attributes (appearance, texture, flavor, general acceptance). Whole carcass-shaking method was used for microbiological analysis. Although a limited antimicrobial effect on microbial flora was seen in treatment groups within the first 3 days of storage compared to the control group, the difference between the groups completely disappeared (p>0.05) on days 7 and 10. The changes in the numbers of the microflora on days 0-10 were 4.5-7.9 log10 cfu/ml for total aerobic mesophiles, 3.6-8.58 log10 cfu/ml for psychrophiles, 2.7-6.7 log10 cfu/ml for coliforms, and 2.2-5.9 log10 cfu/ml for yeast and molds. Salmonella spp. were detected in all groups througout the storage periods in all 3 trials. The pH of the in-bag fluid that was acidic (3.9 in 1 % LA group) or alkaline (11.3 in 8 % TSP group) changed toward neutral pH, and reached to 6.1 in LA group, and 7.0 in TSP group. Sensory evaluation of the cooked breast meat of the carcasses indicated that there were no appreciable difference between the groups between the days 0 and 7. On day 10, the carcasses were spoiled. In addition to proper slaughter hygiene and decontamination applications during slaughter, there has been a need for innovative applications of the decontamination methods to maintain the atimicrobial effect during storage. In-bag applications of various decontaminants have been practiced for different food products. The experimental approach of the present study can be expanded and optimized for poultry products. Key Words: Chicken, shelf life, decontamination, Salmonella