Submitted to: International Journal of Food Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/18/2003
Publication Date: 3/1/2004
Citation: Hinton Jr, A., Cason Jr, J.A., Ingram, K.D. 2004. Tracking spoilage bacteria in commercial poultry processing and refrigerated storage of poultry carcasses. International Journal of Food Microbiology. 91(2):155-165. Interpretive Summary: Experiments were performed to examine the effect of processing and refrigerated storage on bacteria that cause spoilage of fresh chicken. Broilers were taken from different locations in the processing line of a processing plant, and the number of spoilage bacteria on the broilers was determined. The number of bacteria on processed broilers stored in a refrigerator for up to 2 weeks was also determined. The spread of bacteria between broilers during processing was monitored by determining the relationship between bacteria isolated from the carcasses. Findings indicated that although some processing steps increased the number of spoilage bacteria on the broilers, broilers taken from the end of the processing line had fewer bacteria than broilers taken from the beginning of the processing line. Results also showed that bacteria were spread among broilers as they moved through the processing line. Some bacteria survived processing and grew on carcasses during refrigeration. Furthermore, contaminated equipment and water in the plant spread bacteria between broilers processed on different days at the same plant. Results provide information that may be useful in reducing the number of spoilage bacteria associated with broiler chickens and increasing the amount of time that fresh chicken can be kept in the refrigerator.
Technical Abstract: Trials were conducted to examine the effect of processing and refrigerated storage on spoilage bacteria on broiler carcasses. Prescalded, picked, prechilled, and chilled carcasses were obtained from a processing facility, and psychrotrophs in the bacterial flora were enumerated. The size of the population of spoilage bacteria on processed carcasses stored at 4C was also determined. Bacteria were identified and dendrograms of the fatty acid profiles of the isolates were prepared to determine the degree of relatedness of the isolates. Findings indicated that although some processing steps increased carcass contamination, the number of spoilage bacteria recovered from processed carcasses was less than the number of bacteria recovered from carcasses entering the processing line. Acinetobacter and Aeromonas were the primary isolates recovered from carcasses taken from the processing line. During refrigerated storage there was a significant increase in the population of bacteria on the carcasses, and Pseudomonas were the predominant bacteria recovered from these carcasses. Dendrograms of the fatty acid profiles of the isolates indicated that bacterial cross contamination of carcasses occurs during all stages of processing and that some bacteria can survive processing and proliferate on carcasses during refrigeration. Cross contamination was also detected between carcasses processed on different days at the same facility. Findings indicate that although poultry processing decreases carcass contamination by spoilage bacteria, significant levels of bacterial cross contamination occur during processing, and bacteria that survive processing may multiply on the carcasses during refrigerated storage.