Gossner C.M.,Institute of Veille Sanitaire |
Gossner C.M.,U.S. Center for Disease Control and Prevention |
van Cauteren D.,Institute of Veille Sanitaire |
le Hello S.,Institute Pasteur Paris |
And 8 more authors.
Eurosurveillance | Year: 2012
An outbreak of the monophasic variant of Salmonella enterica serotype 4,,12:i:- occurred in November and December 2011 in France. Epidemiological investigation and food investigation with the help of supermarket loyalty cards suggested dried pork sausage from one producer as the most likely source of the outbreak. Despite the absence of positive food samples, control measures including withdrawal and recall were implemented.
Clarisse T.,Agrocampus Ouest |
Michele S.,Chimie Paristech |
Olivier T.,French National Institute for Agricultural Research |
Valerie E.,French National Institute for Agricultural Research |
And 4 more authors.
Food Control | Year: 2013
Staphyloccocus aureus is reported to be one of the most frequent pathogens involved in food-borne diseases associated with dairy products, especially with raw milk cheese. Some strains produce enterotoxins as Staphylococcal enterotoxin A (SEA) which is involved in 75% of food poisoning outbreaks. Actually few methods are both sensitive and specific enough for confirming the diagnosis of staphylococcal food poisoning. In this work, an Enzyme-Linked ImmunoSorbent Assay (ELISA) was set up and optimised to detect SEA in milk and cheese. Various anti-SEA antibodies: polyclonal sera, anti-peptide polyclonal sera and monoclonal antibodies, used for the capture and or detection steps were compared and analysed. The mouse anti-whole SEA polyclonal serum, used as detection detected 32 pg/ml SEA in buffer and 64 pg/ml in milk. These concentrations were well under the limit set for food safety. This assay was also highly specific of SEA and no cross-reaction was observed with the other staphylococcal enterotoxins. In contaminated cheese samples the time of enterotoxin extraction was reduced by using ultrafiltration method instead of dialysis and the detection limits were 1.5-2.5 and 1.9-3 times more sensitive than a commercial kit and the official method, respectively. Preliminary study of SEA detection with the piezoelectric immunosensor allowed detecting and quantifying SEA within 10 min in unprocessed food but the sensitivity was not sufficient. The ELISA assay with mouse antibodies is likely suitable for SEA routine detection not only in dairy product but also in various foods as sauce and liver mousse. © 2012 Elsevier Ltd.
Habimana O.,French National Institute for Agricultural Research |
Habimana O.,Agro ParisTech |
Habimana O.,Nofima Materials AS |
Guillier L.,Laboratoire Of Securite Des Aliments |
And 4 more authors.
Biofouling | Year: 2011
Surfaces in industrial settings provide a home for resident biofilms that are likely to interact with the attachment, growth and survival of pathogens such as Listeria monocytogenes. Experimental results have indicated that L. monocytogenes cells were inhibited by the presence of a model resident flora (Lactococcus lactis) in dual-species continuous flow-biofilms, and are spatially restricted to the lower biofilm layers. Using a new, simplified individualbased model (IBM) that simulates bacterial cell growth in a three-dimensional space, the spatial arrangements of the two species were reconstructed and their cell counts successfully predicted. This model showed that the difference in generation times between L. monocytogenes and L. lactis cells during the initial stages of dual-species biofilm formation was probably responsible for the species spatialization observed and the subsequent inhibition of growth of the pathogen. © 2011 Taylor & Francis.
Commeau N.,French National Institute for Agricultural Research |
Commeau N.,Agro ParisTech |
Commeau N.,Laboratoire Of Securite Des Aliments |
Cornu M.,Agro ParisTech |
And 3 more authors.
Risk Analysis | Year: 2012
Assessing within-batch and between-batch variability is of major interest for risk assessors and risk managers in the context of microbiological contamination of food. For example, the ratio between the within-batch variability and the between-batch variability has a large impact on the results of a sampling plan. Here, we designed hierarchical Bayesian models to represent such variability. Compatible priors were built mathematically to obtain sound model comparisons. A numeric criterion is proposed to assess the contamination structure comparing the ability of the models to replicate grouped data at the batch level using a posterior predictive loss approach. Models were applied to two case studies: contamination by Listeria monocytogenes of pork breast used to produce diced bacon and contamination by the same microorganism on cold smoked salmon at the end of the process. In the first case study, a contamination structure clearly exists and is located at the batch level, that is, between batches variability is relatively strong, whereas in the second a structure also exists but is less marked. © 2012 Society for Risk Analysis.
Navarro P.,University of Pau and Pays de lAdour |
Clemens S.,Laboratoire Of Securite Des Aliments |
Perrot V.,University of Pau and Pays de lAdour |
Bolliet V.,French National Institute for Agricultural Research |
And 4 more authors.
International Journal of Environmental Analytical Chemistry | Year: 2013
A methodology to simultaneously determine mercury (MeHg, IHg) and butyltin (TBT, DBT, MBT) compounds in eel samples was assessed and validated using multiple isotopically enriched species. The developed methodology was able to analyse simultaneously the organometal species accurately and precisely and to correct for the potential transformations/degradations of the different species during the various steps of the analytical procedure. Low detection limits were achieved (0.007-0.17 μg Hg kg-1 for mercury (Hg) species and 0.42-0.71 μg Sn kg-1 for tin (Sn) species) allowing analysis of low-mass samples and thus the analysis at the individual organism scale, including glass eels for which samples dry weight ranged from 60 to 100 mg. The methodology was validated with certified reference materials (BCR-464, BCR-477, BCR-710, DOLT-4 and NIST-2977) and applied to the analysis of these pollutants in two developmental stages of the European eel, Anguilla anguilla: individual whole glass eels and muscle tissue from yellow eels. The Adour estuary (South-west France) was selected to monitor the bioaccumulation of organometal species in these organisms, according their developmental stage, their morphological parameters and the sampling site. The results suggest that the accumulation of methylmercury in glass eel tissue is related to weight, with higher concentrations in smaller individuals. Butyltin concentrations were very close to the limit of detection, and no significant differences were detected between glass and yellow eels. © 2013 Copyright Taylor and Francis Group, LLC.