Microbial profile of broiler carcasses processed at a university scale mobile poultry processing unit

Authors: STEARNS, REBECCA - West Virginia University; BOWEN, KRISTINA - West Virginia University; TAYLOR, ROBERT - West Virginia University; MORITZ, JOE - West Virginia University; MATAK, KRISTEN - West Virginia University; TOU, JANET - West Virginia University; FRESHOUR, ANNETTE - West Virginia University; JACZYNSKI, JACET - West Virginia University; BOLTZ, TIMOTHY - Mississippi State University; Li, Xiang; SHEN, CANGLIANG - West Virginia University

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/15/2024
Publication Date: 2/20/2024
Citation: Stearns, R., Bowen, K., Taylor, R.L., Moritz, J., Matak, K., Tou, J., Freshour, A., Jaczynski, J., Boltz, T., Li, X., Shen, C. 2024. Microbial profile of broiler carcasses processed at a university scale mobile poultry processing unit. Poultry Science. https://doi.org/10.1016/j.psj.2024.103576.
DOI: https://doi.org/10.1016/j.psj.2024.103576

Interpretive Summary: This study analyzed the safety of chicken products processed in mobile units in West Virginia. It focused on evaluating the concentrations and frequencies of foodborne pathogens such as Salmonella, Campylobacter, and E. coli. A total of 96 chicken carcasses, spanning various processing stages (primarily scalding, eviscerating, and chilling), were examined to compare the effectiveness of chilling methods—specifically, using chlorine-infused water versus plain ice water. The findings revealed significant reductions in Salmonella, Campylobacter, and E. coli. Notably, post-evisceration cleaning emerged as a crucial step in preventing Salmonella cross-contamination. Moreover, the study demonstrated that proper chilling with plain ice water alone was sufficient to eliminate Salmonella. However, reducing Campylobacter required chlorine in combination with ice water. This study shows the necessity for further research to optimize processing strategies in mobile units, particularly in ensuring more effective pathogen control.

Technical Abstract: Chicken and chicken products have been associated with foodborne pathogens such as Salmonella, Campylobacter, and Escherichia coli (E. coli). Poultry comprises an important segment of the agricultural economy (75 million birds processed as of 2019) in West Virginia (WV). The risk of pathogens on processed chickens has risen with the increased popularity of mobile poultry processing units (MPPUs). This study evaluated the microbial safety of broiler processed in a MPPU in WV. This study assessed aerobic plate counts (APCs), E. coli counts and the presence/absence of Salmonella and Campylobacter on 96 broiler carcasses following each MPPU step of scalding, eviscerating, and chilling. Samples were either chilled in ice water only (W) or ice water with 5 ppm chlorine (CW). The highest number of bacteria recovered from carcasses were APCs (4.21 log10CFU/mL) and E. coli (3.77 log10CFU/mL; P < 0.05). A total reduction of 0.30 and 0.63 log10CFU/mL for APCs and E. coli, respectively, occurred from chilling carcasses in CW (P < 0.05). Overall, results show that E. coli, Salmonella, and Campylobacter were significantly (P < 0.05) reduced from the initial scalding to the chilling step. However, Salmonella frequency doubled (15.63-34.38%) after the evisceration step, indicating that washing carcasses after evisceration may be a critical control point in preventing cross-contamination by Salmonella. Proper chilling is also an important microbial mitigation step in MPPU processing. Results indicate that Campylobacter was more resistant to chilling than Salmonella. Campylobacter was not completely inactivated until carcasses were chilled in CW, whereas W was sufficient to completely inactivate Salmonella on carcasses. The results led to the conclusion that although 5 ppm chlorine (Cl2) achieved more bacterial reductions than water alone, the reductions were not always significant (P > 0.05). Further MPPU studies are needed to verify more effective chilling and processing strategies.