Salmonella spp. and Escherichia coli biotype I on swine carcasses processed under the hazard analysis and critical...

The present study examined the prevalence of Salmonella spp. and the prevalence and quantity of generic (biotype I) Escherichia coli on carcasses or in pig feces at a pork processing plant operating under the hazard analysis and critical control point-based inspection models project (HIMP) program. The surfaces of carcasses were sponged on 10 separate days over a 30-day period at two processing steps: (i) immediately following exsanguination (100 carcasses), and (ii) after the carcasses were washed, eviscerated, and chilled overnight (122 carcasses). Feces were also collected from 60 of the 100 sponged, postexsanguinated pigs. Salmonella spp. were detected on 73.0% of the 100 postexsanguinated pigs, in 33.3% of the 60 fecal samples, and on 0.7% of the 122 chilled carcasses. E. coli was found on 100.0% of the postexsanguinated pigs and on 30.1% of chilled carcasses tested. The mean concentration of E. coli on carcasses was 1,700 CFU/cm2 immediately after the exsanguination step and 1.1 CFU/cm2 at the chilled carcass stage. Previous studies at this processing plant showed that the pre-HIMP baseline level of Salmonella spp. on the chilled carcasses was 0.8%, indicating that the present HIMP inspection system produced an equivalent level of bacteriological performance.