Influence of Modified Atmosphere Packaging on the Survival of Salmonella Enteritidis PT 8 on the Surface of Chilled Chicken Legs

Abstract

The aim of this study was to find whether low numbers of Salmonella in the presence of natural microflora will survive on the surface of chicken legs stored in 30% CO 2 /70% N 2 and 20% CO 2 /80% O 2 . In four experiments, a total of 240 pieces of chicken leg were inoculated with a Salmonella Enteritidis, PT 8, wildtype strain resulting in initial concentrations of approximately 4 log, 2.5 log, 1.5 log and 0.5 log cells per piece and kept under selected modified atmospheres for 14 days. Counts of Salmonella were determined by the Most Probable Number method (MPN) at days 0, 3, 7, 10 and 14 of storage. No significant increase or decrease in Salmonella numbers was observed in the atmosphere of 20% CO 2 /80% O 2 . In the atmosphere of 30% CO 2 /70% N 2 there was a significant decrease in cell numbers at days 10 and 14; however, this decrease was proved only in experiments with an initial Salmonella concentration of 4 log and 1.5 log cells per piece. We proved that even low numbers of S. Enteritidis in the presence of natural microflora survive well on the surface of poultry stored at 3 °C in both modified atmospheres we tested. In the case of temperature abuse even products with low initial numbers of Salmonella may constitute a health risk for consumers.