Although the refrigeration of eggs within the food supply chain is recommended by multiple studies, the official guidelines on egg storage conditions within the food supply chain remain somehow unclear and highly variable among countries. In this study, various microbiological parameters of free-range chicken eggs from a small-scale farm were examined. The aim was to evaluate the influence of different storage temperatures on eggshell microbial load. In addition, the survivability and growth kinetics of Salmonella enterica serovar Enteritidis (S. Enteritidis) were determined in dependence of the storage temperature. Our results showed significantly higher counts of the total aerobic mesophilic bacteria in eggs stored at 22 °C in comparison to eggs stored at 4 °C. Furthermore, storage at 22 °C supported the growth kinetics of S. Enteritidis on the eggshell as well as its penetration to the inner shell membranes. In contrast, storage at 4 °C prevented the replication of S. Enteritidis on the eggshell and its penetration into the internal egg contents. Consistent with the findings of other studies, our results clearly demonstrate the benefits of eggs refrigeration during transport and storage.
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