SURVIVAL OF LISTERIA-MONOCYFOGENES AND SALMONELLA-TYPHIMURIUM AND QUALITY ATTRIBUTES OF COOKED PORK CHOPS AND CURED HAM AFTER IRRADIATION

Cooked pork chops (pumped with salt/polyphosphate brine or untreated) and cured hams were inoculated with Listeria monocytogenes and Salmone lla typhimurium. The samples were irradiated at low (0.75 to 0.90 kGy) or medium doses (1.8 to 2.0 kGy), and each dose was delivered at eith er a low (2.5 M/min conveyor speed) or high (5.4 M/min) dose rate. Low -dose irradiation reduced L. monocytogenes by more than 2 log and S. t yphimurium by 1 to 3 log. Pathogen populations and total plate counts (TPC) were reduced to undetectable levels by medium doses. No meat qua lity attributes were affected, and no dose rate effect was observed. N itrite reduced (P < 0.05) both pathogens and TPC during 7 degrees C st orage in ham, especially when combined with low-dose irradiation.