Assessment of the adequacy of cleaning of equipment used for breaking beef carcasses

Enumeration of bacteria on product entering or leaving a beef carcass breaking process showed that the meat was being contaminated with Escherichia coli during the process. The equipment used in the process appeared to be well cleaned, and few bacteria were recovered from meat-contacting surfaces of cleaned equipment. However, careful inspection of the cleaned equipment revealed obscured locations in the equipment which harboured detritus that carried large numbers of aerobic bacteria including E. coli. The findings indicated that when the equipment was operated with wetting of the meat-contacting surfaces, bacteria from the persisting detritus were transferred to the meat-contacting surfaces and the meat. Similar increases in the numbers of E. coli on product as a result of the carcass breaking processes were observed at two of three other plants where the processes were examined. It therefore appears that compliance with current regulatory agency recommendations for conducting and monitoring the cleaning of carcass breaking equipment will not assure the control of hazardous microbiological contamination from carcass breaking equipment. Consequently, it is suggested that the adequacy or otherwise of each cleaning process should be assessed by reference to the mean numbers of suitable indicator organisms on product entering and leaving the production process that employs the cleaned equipment.