Microbiological findings in ready-to-eat and precooked food distributed in public catering halls in Cagliari Province, Italy

During this research 159 samples of ready-to-eat and precooked food were examined for the detection of Salmonella spp., Listeria monocytogenes, Escherichia coli, coagulasepositive staphylococci and Enterobacteriaceae, bacterial count. All samples were negative for Salmonella spp. and Listeria monocytogenes; although a low count of coagulase-positive staphylococci (no. 5 samples) and E. coli (no. 3) was found. We proceeded with the identification of the isolates on every sample with high, moderate and low-count of Enterobacteriaceae, to better understand the microbial ecology. The Enterobacteriaceae species most frequently detected were Pantoea spp. (29.62%), Enterobacter cloacae (20.37%) and Serratia liquefaciens (12.96%); other different species of Enterobacteriaceae were detected with a <10% presence. Since there are no legal regulations indicating tolerance or limit values or this kind of microorganisms related to the samples, it would be appropriate, in the presence of high count of Enterobacteriaceae or by type of ready-to-eat and precooked food, to proceed with the identification of every microorganism.