Standardized Microbiological Sampling and Testing Procedures for the Beef Industry

Abstract

Standardized microbiological sampling and testing procedures were developed that can be used throughout the beef slaughter and processing industry to facilitate the collection and any desired compilation of comparative data. Twenty samples each from carcasses (brisket, flank, and rump areas combined); subprimal cuts (clods); lean trim; and cutting and/or conveyor surfaces were collected in three slaughter and processing operations, with the first operation being a preliminary trial and resulting in no reported data. Microbiological analyses for Clostridium perfringens, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, Campylobacter jejuni/coli, total coliforms, E. coli Biotype I, and aerobic mesophilic bacteria (aerobic plate count, APC) were performed on all samples by an outside laboratory. The procedures developed were effective in allowing samples to be collected, shipped, and analyzed in the same manner for all operations. From a logistical standpoint, approximately 20 samples each of carcasses, clods, lean trim, and surfaces could be taken within 4 to 6 h by five people. Forty samples each of carcass, clod, lean trim, and conveyor surfaces from two plants tested negative for E. coli O157:H7, Salmonella spp., and Listeria spp., with the exception of L. monocytogenes being isolated from one carcass and one clod sample. APCs and total coliform counts were between 103 to 105 and 102 to 103 CFU/cm2 or CFU/g, respectively, for the 40 samples each of carcasses, clods, and lean trim. APCs for surface swab counts ranged from ≤ 10 to 103 CFU/cm2.

Prevalence of Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella in Two Geographically Distant Commercial Beef Processing Plants in the United States

“…Hide removal and evisceration are considered to be procedures in which pathogens are transferred onto carcasses (15,36). Escherichia coli O157:H7, Salmonella, Listeria spp., and L. monocytogenes have been found to be contaminants of carcasses after dehiding and other slaughtering/dressing processes (4,5,11,12,20,21,23,26,27,37,39,42).…”