Contamination sources, serogroups, biofilm-forming ability and biocide resistance of Listeria monocytogenes persistent in tilapia-processing facilities

Autor(es)

Vazquez-Sanchez, Daniel ^[1] ; Galvao, Juliana Antunes ^[1] ; Oetterer, Marilia ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Luiz de Queiroz Coll Agr ESALQ, Dept Agrifood Ind Food & Nutr, Lab Freshwater Fish & Seafood Technol, Ave Padua Dias 11, BR-13418900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF FOOD SCIENCE AND TECHNOLOGY-MYSORE; v. 54, n. 12, p. 3867-3879, NOV 2017.
• Citações Web of Science: 5

Resumo

The major contamination sources, serogroups, biofilm-forming ability and biocide resistance of Listeria monocytogenes persistent in tilapia-processing facilities were assessed. Twenty-five processing-control points were examined twice in two factories, including whole tilapias, frozen fillets, water and food-contact surfaces. L. monocytogenes were detected in 4 and 20% of points of Factory A and B respectively, but at low concentrations. Contamination was due to inadequate handling of tilapias in the slaughter room of Factory A and to the application of ineffective sanitizing procedures in Factory B. Seven strains were characterized by RAPD-PCR using primers HLWL85, OPM-01 and DAF4. Genotypic similarity allowed tracing the contamination source of tilapia fillets in Factory B and detecting a prevalent strain in Brazilian tilapia-processing facilities. The serogroup II (including the serotype 1/2c) was the most frequently found, followed by serogroup I (1/2a) and III (1/2b), whereas the serotype 4b was not detected. All strains showed high biofilm-forming ability on stainless steel and polystyrene, but biofilm formation was positively correlated with the type of origin surface. Biofilms were highly resistant to peracetic acid and sodium hypochlorite, being required doses higher than those recommended by manufacturers to be eradicated. Peracetic acid was more effective than sodium hypochlorite, but the use of disinfectants with similar mechanisms of action increases the risk of cross-resistance. Case-by-case approaches are thus recommended to determine the sources and degree of contamination present in each factory, which would allow applying precise responses to control the persistence of bacterial pathogens such as L. monocytogenes. (AU)

• Processo FAPESP: 14/20590-0 - Eficácia dos procedimentos de limpeza aplicados em plantas de processamento de Tilápia: avaliação de alternativas mais seguras ao ambiente
• Beneficiário: Daniel Vázquez Sánchez
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado