Quantitative microbiological risk assessment of Shiga toxin-producing Escherichia coli contamination for the beef steak supply chain in China.

Abstract

Shiga toxin-producing Escherichia coli (STEC) has become a significant threat to public health, with cattle recognized as the primary reservoir. To assess the potential risk of STEC contamination, a quantitative microbiological risk assessment (QMRA) simulation was conducted for the beef steak supply chain in China. This simulation integrated prevalence data from slaughterhouse processing stages, distribution temperature variations, and consumer cooking practices into simulation models. The result showed that the mean probability of illness per serving was 3.03 × 10-7 and temperature fluctuations during distribution led to a 1.84-fold of such risk. The results of the sensitivity analysis indicate that cooking procedures and initial STEC contamination levels on cattle hides are key factors influencing risk of illness. The following scenario analysis indicated that different formulations for carcass decontamination and different cooking methods could result in the greatest relative risk reduction. The quantitative microbial risk assessment conducted in this study not only quantifies the risk of consuming contaminated beef steaks in China, but also proposes a quantitative risk assessment-driven solution for identifying critical control points and enhancing food safety management in industry practice.