Attachment and Proliferation of Bacteria on Meat

The attachment of bacteria ( Serratia marcescens , Staphylococcus aureus , Streptococcus faecalis , Salmonella arizonae , Pseudomonas aeruginosa , and Listeria monocytogenes ), to lean muscle tissue and fat tissue was investigated. The number of cells attached to the meat was directly proportional to the initial cell concentrations present. There was no significant difference in the number of cells attached between the lean muscle tissue and fat tissues among the organisms tested. All bacteria tested except P. aeruginosa proliferated better on the lean muscle tissues than on the fat tissue at ambient temperature for 72 h. No significant attachment competition to tissue samples was seen between L. monocytogenes and P. aeruginosa , however, the numbers of P. aeruginosa were greater than L. monocytogenes (after 24 h). Similarly, no competitive attachments between S. aureus and S. marcescens , S. faecalis and S. arizonae were observed; but the numbers of S. marcescens were greater than S. aureus , and S. arizonae were greater than S. faecalis , when the inoculated meat was incubated at room temperature for 24 h.