Modeling transfer of Escherichia coli O157:H7 and Staphylococcus aureus during slicing of a cooked meat product

Department of Food Science and Technology, University of Córdoba, Campus de Rabanales, C-1, 14014 Córdoba, Spain.
Meat Science (Impact Factor: 2.62). 08/2007; 76(4):692-9. DOI: 10.1016/j.meatsci.2007.02.011
Source: PubMed


Cross contamination is one of the most important contributing factors in foodborne illnesses originating in household environments. The objective of this research was to determine the transfer coefficients between a contaminated domestic slicing machine and a cooked meat product, during slicing. The microorganisms tested were Staphylococcus aureus (Gram positive) and Escherichia coli O157:H7 (Gram negative). The results showed that both microorganisms were able to transfer to all slices examined (20 successively sliced) and at different inoculum levels on the blade (10(8), 10(6) and 10(4)cfu/blade). The results also showed that the number of log cfu transferred per slice, during slicing, decreased logarithmically for both microorganisms at inoculum levels of 8 and 6log cfu/blade. The type of microorganism significantly influenced transfer coefficients (p<0.05) and there was an interaction between inoculum level and transfer coefficient for S. aureus (p<0.05), but not E. coli O157:H7. Finally, to describe bacterial transfer during slicing, two models (log-linear and Weibull) were fitted to concentration on slice data for both microorganisms (at 6 and 8 log cfu/blade), obtaining a good fit to data (R(2)⩾0.73).

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Available from: Ewen Cameron David Todd, Oct 13, 2015
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    • "The presence of E. coli O157:H7 and S. aureus on food contact surfaces in meat fabrication plants and retail facilities is well documented (Malheiros et al., 2010; Perez-Rodriguez et al., 2010; Samelis et al., 2005; Aslam et al., 2004; Reij et al., 2004; Rivera-Betancourt et al., 2004). In such cases, cross contamination might occur from contaminated surfaces to meat products if handling and manufacture are performed under nonhygienic conditions (Chen et al., 2001; Montville et al., 2001; Reij et al., 2004; Pérez-Rodríguez et al., 2007; Luber, 2010). Better knowledge about survival of these pathogens on stainless steel surfaces under real conditions could help to better assess the impact of cross contamination events during food preparation. "
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    Food Microbiology 04/2013; 33(2):197-204. DOI:10.1016/ · 3.33 Impact Factor
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    • "and d could be associated to the biofilm formation on the meat surface, which may prolong the survival period. Several studies have shown attachment of different microorganism, including S. aureus to poultry surfaces and meat (Dodd, Chaffey, & Waites, 1988; Pérez-Rodríguez et al., 2007). They found that these are parts of the flora in food processing facilities, thus were not only associated with the slaughtering process, and represented a source of cross-contamination of food (Baird- Parker, 2000). "
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    • "Distribution parameters for normal, lognormal, and Weibull distributions are reported for the data on fraction virus transferred between surfaces (f) stratified by phage type. These distributions are used to describe microbial and ⁄ or chemical transfer (Chen et al. 2001; Beamer et al. 2002; Pérez Rodríguez et al. 2007). Fivefold cross-validation and Kolmogov-Smirnoff methods were used to determine distribution parameters and goodness-of-fit. "
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