Unidad de Cultura Científica y de la Innovación

Fundación Descubre

This technique, based on mathematical calculations, enables definition of optimal storage temperature for these products, with the aim to avoid appearance and development of microorganisms such as Salmonella or Listeria monocytogenes.

Researchers at the Bromatological Hygene Research Group (HIBRO) from the Faculty of Veterinary Medicine at the University of Cordoba and the Agricultural Technology Institute of Castilla and León (ITACyL) have developed a new method to determine how Salmonella and Listeria monocytogenes pathogens propagate in fresh pork. These organisms are characterized by their ability to survive at very low temperatures and can compromise consumer health when present at high concentrations. Researchers analyzed how changes in temperature affect concentration levels of these pathogens in meat products, from the point of sale to they arrival to households.

In the article “Determining Probabilistic approach for Salmonella spp. and L. monocytogenes concentration in pork meat from presence/absence microbiological data”, published in the International Journal of food microbiology, the research team has shown that application of mathematical techniques based on probabilistic calculations are effective in identifying how pathogens are distributed in pork fresh products.'Refrigerated storage inhibits growth of microorganisms, however some are able to survive at low temperatures. This mathematical method has made it possible to calculate pathogen concentration in contaminated lots and improve control of raw material and processing operations, thereby minimizing risks associated with fresh meat”, as explained by researcher Antonio Valera from the University of Cordobato to Fundación Descubre.

To achieve these results, experts purchased monthly and for one year a batch of fresh pork, packaged in protective atmosphere, from a local supermarket in the province of Córdoba. 'Later, in the laboratory, we analyzed samples bought at market or point of sale and also after storage at controlled temperatures of 4 and 12° C”, Prof. Valera explains.

“Next step was to estimate the prevalence of Salmonella and Listeria monocytogenes in each of the samples. For this purpose, we used probabilistic methods that enabled us to define and compare the concentration distributions of these two pathogens'

Industrial Applications

The conclusions drawn from this study can be used both by Industries to establish optimal storage temperatures for their products and by risk management companies and health authorities. 'This mathematical approach will improveme the production process and the design of new procedures for detection of organisms that can reach levels hazardous to health', Prof. Valera says.

This research has opened new lines of work related to development of more sensitive analytical techniques capable of detecting contamination of samples with pathogens which are hazardous to consumer security. “In future studies, we will progress to study the distribution of microorganisms in other food categories, with the aim to optimize sampling systems suitable for pathogen detection', he concludes.

These results were achieved as part of Baseline European project, “Selection and improving of fit-for-purpose sampling procedures for specific foods and risks”, funded by the 7th Framework Programme of the European Union, whose principal investigator is Professor Rosa María García Gimeno from the University of Cordoba.

Reference:Valero A, Hernandez M, De Cesare A, Manfreda G, García-Gimeno RM, González-García P, Rodríguez-Lázaro D. ‘Probabilistic approach for determining Salmonella spp. and L. monocytogenes concentration in pork meat from presence/absence microbiological data’. International Journal of food microbiology.