Bifidobacteria as indicators of faecal contamination along a sheep meat production chain

Aims: The potential use of bifidobacteria as indicators for faecal contamination was studied along a sheep meat production and processing chain. The levels of bifidobacteria were compared with those of Escherichia coli. Total viable counts were followed along the chain (244 samples). Methods and Results: Forty-three per cent of the samples contained bifidobacteria, of which 15% were solely detected using a PCR method based on the hsp60 gene and not by a culture-based method. Bifidobacteria were detected in only three of nine sheep faeces samples using one or the other method. However, carcasses (types C and E) were highly contaminated. These sample types (30% and 28%, respectively) were positive for bifidobacteria and negative for E. coli. The species Bifidobacterium pseudolongum and Bif. thermophilum, isolated from faecal samples, were predominant. Bifidobacterium choerinum were found in C, D, E and F sample types. Conclusions: Bifidobacteria were shown more efficient than E. coli in carcasses samples. The presence of Bif. choerinum suggested a faecal pork contamination. Significance and Impact of the Study: Detection and identification of bifidobacteria, in correlation with E. coli counting, should improve hygiene quality of mutton processing chains.BIFI

Microbiological counting in lamb carcasses from an abattoir in São Paulo, Brazil Contagens microbiológicas em carcaças ovinas de um abatedouro de São Paulo, Brasil

The consumption of lamb meat in Brazil has increased in the last years but little information about the microbiological quality of this product is available. To evaluate the hygienic-sanitary conditions of lamb carcasses, the quantification of microorganism populations indicators (mesophiles and psychrotrophs; total and thermotolerant coliforms; Escherichia coli; moulds and yeasts) and the pathogenic microorganisms indentification (Salmonella sp. and Listeria spp.) were performed. A total of 60 lamb carcasses were sampled from one abattoir in São Paulo. Swab samples were collected from three points (forequarter, back and hindquarter) on the muscle surface after carcasses final washing. Statistical analysis consisted of descriptive evaluation of the results whose counts were grouped by intervals of microorganism populations. Counts ranged from 1.0 x 10¹ to 8.0 x 10(4) colony-forming unit cm-2 (CFU cm-2) for mesophiles; 1.0 x 10(0) to 4.4 x 10(4)CFU cm-2 for psychrotrophs; < 1.0 x 10(0) to 4.4 x 10(4)CFU cm-2 for moulds and yeasts; < 0.3 to > 32.0 most probable number/cm² (MPN cm-2) for total and thermotolerant coliforms and Escherichia coli. Salmonella sp. and Listeria spp. were not found in any of the carcasses. Most carcasses presented low counts for all microorganisms. Overall results may be explained by the small size of the industry where the study was taken. Results suggest that good microbiological quality lamb meat is possible to be obtained, but improvement in hygienic-sanitary conditions is still required.<br>O consumo de carne ovina tem aumentado nos últimos anos, no Brasil. Entretanto, pouca informação sobre a qualidade desse produto está disponível. Com o intuito de avaliar as condições higiênico-sanitárias das carcaças ovinas, foram realizadas a quantificação das populações de microrganismos indicadores (mesófilos e psicrotróficos; coliformes totais e termotolerantes; Escherichia coli; bolores e leveduras) e a identificação de microrganismos patogênicos (Salmonella sp. and Listeria spp.). Um total de 60 carcaças foram amostradas em um frigorífico, em São Paulo, entre fevereiro e dezembro de 2006. Suabes foram coletados em três pontos (dianteiro, lombo e traseiro), na superfície muscular das carcaças, após a lavagem final destas. A análise estatística consistiu na avaliação descritiva dos resultados cujas contagens foram agrupadas em intervalos populacionais. As contagens variaram de 1,0 x 10¹ a 8,0 x 10(4)UFC cm-2 para mesófilos; de 1,0 x 10(0) a 4,4 x 10(4)UFC cm-2 para psicrotróficos; de < 1,0 x 10(0) a 4,4 x 10(4)UFC cm-2 para bolores e leveduras; de < 0,3 a > 32,0 NMP cm-2 para coliformes totais e termotolerantes; e Escherichia coli. Salmonella sp. e Listeria spp. não foram detectadas em nenhuma das amostras coletadas nas carcaças. A maioria das carcaças apresentou baixas contagens para todas as categorias de microrganismos. Os resultados encontrados podem ser explicados pelo pequeno tamanho da indústria onde o trabalho foi realizado e sugerem que carne ovina de boa qualidade microbiológica pode ser obtida. No entanto, melhorias nas condições higiênico-sanitárias ainda são necessárias