Analysis of Key Control Points of Microbial Contamination Risk in Pork Production Processes Using a Quantitative Exposure Assessment Model

Tengteng Yang; Ge Zhao; Yunzhe Liu; Lin Wang; Yubin Gao; Jianmei Zhao; Na Liu; Xiumei Huang; Qingqing Zhang; Junhui Liu; Xiyue Zhang; Junwei Wang; Ying Xu

doi:10.3389/fmicb.2022.828279

Analysis of Key Control Points of Microbial Contamination Risk in Pork Production Processes Using a Quantitative Exposure Assessment Model

Front Microbiol. 2022 Mar 24:13:828279. doi: 10.3389/fmicb.2022.828279. eCollection 2022.

Authors

Tengteng Yang^{1

2}, Ge Zhao¹, Yunzhe Liu¹, Lin Wang¹, Yubin Gao¹, Jianmei Zhao¹, Na Liu¹, Xiumei Huang¹, Qingqing Zhang¹, Junhui Liu¹, Xiyue Zhang¹, Junwei Wang¹, Ying Xu²

Affiliations

¹ Laboratory of Pathogenic Microorganisms Inspection, Livestock and Poultry Products Quality & Safety Risk Assessment Laboratory (Qingdao) of MARA, China Animal Health and Epidemiology Center, Qingdao, China.
² College of Food Science and Engineering, Ocean University of China, Qingdao, China.

Abstract

Pork is one of the most common foods causing microbial foodborne diseases. Since pork directly enters the market after slaughtering, the control of microbial contamination in the slaughtering processes is the key to ensuring the quality and safety of pork. The contamination level of Escherichia coli, a health-indicator bacterium, can reflect the risk level of potential pathogens. In order to assess the E. coli exposure risk of pork during slaughtering and to identify the key control points, we established an E. coli quantitative exposure assessment model for swine-slaughtering processes in slaughterhouses of different sizes. The model simulation data indicated the E. coli contamination pattern on the surfaces of swine carcasses during slaughtering. The changes in E. coli contamination were analyzed according to the simulation data of each slaughtering process. It was found that the number of E. coli after trimming in big and small slaughterhouses increased to the maximum values for the whole processes, which were 3.63 and 3.52 log₁₀ CFU/100 cm², respectively. The risk contribution of each slaughtering process to the E. coli contamination on the surface of terminal swine carcasses can be determined by correlation analysis. Because the absolute value of correlation coefficient during the trimming process was maximum (0.49), it was regarded as the most important key control point. This result can be further proved via the multilocus sequence typing of E. coli. The dominant sequence type before trimming processes was ST10. ST1434 began to appear in the trimming process and then became the dominant sequence type in the trimming and pre-cooling processes. The model can provide a theoretical basis for microbial hygiene supervision and risk control in swine-slaughtering processes.

Keywords: key control points; microbial contamination risk; multilocus sequence typing; quantitative exposure assessment model; swine-slaughtering processes.