Publications by authors named "Lena Barre"
Article Synopsis
- Ready-to-eat food products can become contaminated by harmful bacteria during processing, which may form protective biofilms in industrial environments.
- To monitor bacterial contamination, food industry professionals need to regularly sample surfaces for pathogens like Listeria monocytogenes and spoilage bacteria such as Pseudomonas fluorescens.
- A 2010 survey across 14 EU states revealed that professionals prefer friction sampling methods (using gauze pads, swabs, and sponges) over contact methods; however, recent comparisons showed no significant difference in effectiveness between these methods for recovering the target bacteria from biofilms.
During the past six years, new species of the genus Listeria have been isolated from foods and other environmental niches worldwide. The Standard method EN ISO 11290-1 that is currently under revision will include in its scope all Listeria species in addition to L. monocytogenes.
View Article and Find Full Text PDFFor the enumeration of Listeria monocytogenes (L. monocytogenes) in food, a sensitive enumeration method has been recently developed. This method is based on a membrane filtration of the food suspension followed by transfer of the filter on a selective medium to enumerate L.
View Article and Find Full Text PDFArticle Synopsis
- - The isolation of Listeria monocytogenes from food often faces challenges due to its potential overgrowth by other Listeria species during double enrichment, which can lead to false negatives in testing.
- - Experimental analysis revealed that L. monocytogenes can be outgrown by Listeria innocua during the late exponential growth phase due to interactions, while a dominant L. monocytogenes strain can also suppress Listeria welshimeri’s growth rate.
- - Despite testing various factors in the ISO 11290-1 methodology, no single determinant was found for the overgrowth, but adding agar to the broth significantly reduced overgrowth in mixed strain experiments, indicating competition for nutrients plays a key role
Obtaining quantitative data concerning the relative impact of various factors that may influence bacterial growth is of great importance for microbial risk assessment and predictive microbiology. The objective of this work was to investigate the effect of the initial Listeria monocytogenes density on all the growth parameters of this pathogen (lag phase duration, growth rate and maximum population density attained) on a sterile solid model system mimicking smoked fishery products, and in real cold-smoked salmon, a product likely to be contaminated with L. monocytogenes.
View Article and Find Full Text PDF