5 9 100 for inoculation of the five species together. A 100-lL aliquot of each dilution was inoculated onto the surface of the pork sample and stored at 4 C for four hours. Controls consisted of uninoculated samples treated identically to the inoculated ones. When each of the pork samples transferred into a sterile 250-mL Erlenmeyer flask, Ninety milliliters of TSB was added to obtain the proportion 1:10 (sample weight/total weight). To suspend the bacteria, the bottles were shaken for 10 min at 200 rpm. The same selective media and protocol described above were used for enumeration of
bacteria. The samples were incubated for overnight at 30 ± 1 C. After overnight culture, a 1.5-mL portion of rinse fluid also
was removed from each bottle and placed in a sterile 2-mL microcentrifuge tube for DNA extraction. DNA of the
pellet was extracted using the TIANamp Bacteria DNA Kit according to the manufacturer’s instruction, and the PCR
products were checked as above.