Comparison of processing parameters in small and very small beef processing plants and their impact on Escherichia coli prevalence

Increasing consumer demands markets for local and regional foods emphasize the need for bridging the gap between large and small beef processing plants to overcome foodborne illnesses due to pathogens associated with such foods. The current study evaluates operational differences in small and very small plants, which contribute to the efficacy of interventions and their impact on prevalence of aerobic bacteria, total coliforms, and E. coli. A total of 5 beef processing plants were sampled (2 USDA inspected, 1 state inspected, and 2 custom state inspected plants). It was observed that small plants achieved the greatest reduction (0.92 log10 CFU/sq. cm) during initial processing. Very small local plants obtained the largest overall log reductions (0.8-2.1 log10  CFU/cm2) of E. coli O157:H7 on beef carcasses. Further identification revealed higher prevalence of E. coli O157 (84.2%) and STEC (55.2%) in the large plants and molecular characterization of the 19 confirmed STEC isolates revealed 57.89% of the isolates being E. coli O103, while 0.05% were identified as E. coli O26. Results from our study provide insight to differences in operational capabilities between large and small beef processors that can assist in beef safety research to mitigate foodborne illness.