Impact of the pre-slaughter period on the contamination of bovine leather and the operational sanitary procedure for skinning on the quality and microbiological safety of the carcass

Abstract

Sanitary procedures are essential in cattle slaughter processes to minimize microbiological hazards from meat consumption. This study aimed to verify the influence of the pre-slaughter period and the correct execution of the operational sanitary procedure (OSP) for skinning in the breast region on the counts of indicator microorganisms and the occurrence of enteropathogens in the hides and carcasses of cattle. Forty-eight animals were evaluated and divided into 12 clusters, half of which were allowed 13 h of preslaughter rest, while the other half were allowed 23 h of pre-slaughter rest. The presence of microbiological indicators, including Salmonella spp., Listeria spp., and Shiga toxin-producing (STEC), enteropathogenic (EPEC), and enterohemorrhagic (EHEC) Escherichia coli, were evaluated in superficial samples of leather and carcass in which the OSP for skinning of the chest was performed either correctly or incorrectly. There was no significant effect (p > 0.05) of the pre-slaughter period on the counts of total coliforms, E. coli, enterobacteria, and mesophilic aerobics in the hide or carcass, although, in the carcasses, this difference was 93.4% for mesophilic aerobics and enterobacteria in the group of animals subjected to 23 h of rest compared to those subjected to 13 h of rest. Regarding the correct execution of the skinning OSP, there was also no significant effect (p > 0.05) on the indicator quantifications, but in relation to the presence of enteropathogens, it was possible to proportionally identify more EPEC and STEC in carcasses subjected to the wrong OSP, as it was only possible to identify Salmonella spp. and EHEC in carcasses subjected to the wrong OSP. The correct execution of the OSP for skinning incision in the chest region of the animal reduced the microbiological risk of the carcasses for the presence of enteropathogens and facilitated compliance with the microbiological standards for the carcass.