Interference of raw milk autochthonous microbiota on the performance of conventional methodologies for Listeria monocytogenes and Salmonella spp. detection

Autor(es)

Nero, Luis Augusto ^{[1, 2]} ; de Mattos, Marcos Rodrigues ^[3] ; Ferreira Barros, Marcia de Aguiar ^[4] ; Beloti, Vanerli ^[3] ; Gombossy de Melo Franco, Bernadette Dora ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Fac Ciencias Farmaceut, Dept Alimentos & Nutr Expt, BR-05508900 Sao Paulo - Brazil

^[2] Univ Fed Vicosa, Dept Vet, BR-36570000 Vicosa, MG - Brazil

^[3] Univ Estadual Londrina, Dept Vet Prevent Med, BR-86051990 Londrina, PR - Brazil

^[4] Univ Brasilia, Fac Agron & Med Vet, BR-70910970 Brasilia, DF - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MICROBIOLOGICAL RESEARCH; v. 164, n. 5, p. 529-535, 2009.
• Citações Web of Science: 10

Resumo

Pathogen detection in foods by reliable methodologies is very important to guarantee microbilogical safety. However, peculiar characteristics of certain foods, such as autochthonous microbiota, can directly influence pathogen development and detection. With the objective of verifying the performance of the official analytical methodologies for the isolation of Listeria monocytogenes and Salmonella in milk, different concentrations of these pathogens were inoculated in raw milk treatments with different levels of mesophilic aerobes, and then submitted to the traditional isolation procedures for the inoculated pathogens. Listeria monocytogenes was inoculated at the range of 0.2-5.2 log CFU/mL in treatments with 1.8-8.2 log CFU/mL. Salmonella Enteritidis was inoculated at 0.9-3.9 log CFU/mL in treatments with 3.0-8.2 log CFU/mL. The results indicated that recovery was not possible or was more difficult in the treatments with high counts of mesophilic aerobes and low levels of the pathogens, indicating interference of raw milk autochthonous microbiota. This interference was more evident for L. monocytogenes, once the pathogen recovery was not possible in treatments with mesophilic aerobes up to 4.0 log CFU/mL and inoculum under 2.0 log CFU/mL. For S. Enteritidis the interference appeared to be more non-specific. (C) 2007 Elsevier GmbH. All rights reserved. (AU)

• Processo FAPESP: 01/13076-8 - Caracterizacao do risco microbiologico associado ao consumo de leite cru.
• Beneficiário: Luís Augusto Nero
• Modalidade de apoio: Bolsas no Brasil - Doutorado