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Abstract: A study was undertaken to examine hygienic control of the slaughter and dressing process for beef cattle at Australian export processing establishments. Samples were collected from two points during the process: immediately after hide removal and at the completion of dressing before the commencement of chilling. Hindquarter and forequarter samples were collected from 24 establishments, half of which (n = 12) used some form of microbial intervention (in addition to trimming). The overall contamination level on carcass sides was low and was reduced between hide removal and entering the chiller. The concentration and prevalence of indicator bacteria were higher on samples from hindquarters than on samples from forequarters. Application of an intervention, such as hot water, in addition to trimming resulted in a greater reduction in the concentration and prevalence of indicator bacteria than trimming alone, although the level of Escherichia coli and coliform bacteria on all samples was too low to allow meaningful comparisons to be made. Salmonellae were isolated from 2.09 and 0.56% of samples after hide removal and before chilling, respectively. Application of an intervention in addition to trimming did not result in a significant reduction (P = 0.4) of Salmonella prevalence on prechill carcasses. Low levels of bacteria were found on carcasses after hide removal. This, combined with small reductions as a result of trimming and sometimes other interventions, resulted in carcasses with very low levels of bacterial contamination. If performance metrics were to be applied to the slaughter and dressing process, a measure of the expected contamination at the end of the process would provide a more unequivocal measure of the process than either contamination on the carcass after hide removal or any reduction achieved as a result of the dressing process., (Copyright ©, International Association for Food Protection.)

Two studies were undertaken to determine the microbiological status of sheep carcass meat and frozen, bulk-packed sheep meat produced in Australia. Samples were collected from 470 sheep carcasses and 415 cartons of frozen sheep trimmings over a period of approximately 12 months. Samples were collected from plants processing sheep carcasses for domestic or export markets. On carcasses, where bacterial counts were obtained, the mean of the log10 aerobic plate count (APC) was 3.92/cm2, the geometric mean of the most probable number (MPN) per square centimeter of Escherichia coli (biotype I) was 23, and the geometric mean of the coliform count was 38 MPN per cm2. A high percentage (75%) of samples was positive for E. coli (biotype I), 81% were positive for coliforms, 5.74% were positive for Salmonella spp., and 1.29% were positive for Campylobacter. Bacterial counts were higher on carcasses chilled over a weekend than on carcasses chilled for 24 h. The total number of bacteria on carcasses processed for domestic markets was similar to that on carcasses processed for export markets. E. coli O157 was not isolated from any of the 465 samples tested. Of the frozen export samples that tested positive, the mean of the log10 APC was 3.47/g, the geometric mean of the E. coli (biotype I) count was 9 MPN per g, and the geometric mean of the coliform count was 19 MPN per g. Of the frozen export samples tested, 48% were positive for E. coli (biotype I), 58% were positive for coliforms, and 6.5% were positive for Salmonella spp. E. coli O157 was recovered from 1 of 343 frozen sheep meat samples tested (0.29%). Bacterial counts were higher on samples of domestic product than on samples of export product. Results from both surveys are compared with data from similar studies conducted in other countries.

Two studies were undertaken to determine the microbiological of beef carcass meat and frozen boneless bulk packed beef produced in Australia. Samples were collected from 1,063 beef carcasses and from 929 cartons of frozen boneless bulk packed beef over a period of approximately 12 months. Samples were collected from works processing beef carcasses for the Australian domestic market and from works targeting export markets. On carcasses processed for export markets, where bacterial counts were obtained, the log10 mean of the APC (aerobic plate count) was 3.13 CFU/cm2, the geometric mean of the coliform count was 19 MPN/cm2, and the geometric mean of Escherichia coli was 13 MPN/cm2. A small percentage (0.59%) of export samples were found positive for Listeria monocytogenes, 0.16% were positive of r coagulase-positive for Campylobacter jejuni/coli, 0.22% were positive for Salmonella spp., and 29% were positive for coagulase-positive Staphylococcus spp. Bacterial numbers were lower on carcasses processed for export markets and higher carcasses chilled for more than 24 h. Escherichia coli O157 was recovered from 4 of 893 export carcasses tested (0.45%). Of the export frozen boneless bulk packed beef samples that tested positive, the log10 mean of the APC was 2.5 CFU/g, the geometric mean of the coliform count was 15 MPN/g, and the geometric mean number of e. coli was 15 MPN/g. Three of 787 export frozen samples (0.38%) tested positive for Salmonella spp., E. coli O157 was not isolated from any of the 685 export frozen samples tested for this bacteria. Export samples tested for this bacteria. Export samples on average had lower APCs than domestic samples. Results from both surveys are compared with data from similar studies in other countries.