Survival of Selected Indicator and Pathogenic Bacteria in Refrigerated Pizzas

This study was conducted to determine the shelf life of previously frozen pizzas stored at refrigeration temperatures. Pizzas were prepared using meat inoculated with Escherichia coli , Staphylococcus aureus , and Salmonella typhimurium . The pizzas were frozen, then stored at 3 and 10°C. Samples were analyzed every 2 d for 14 d. Sensory analysis was conducted every day for 8 d using uninoculated product. There was a significant (P<0.05) increase in the population of E. coli between 8 and 10 d at 10°C. There were no significant (P>0.05) differences in the populations of S. typhimurium or S. aureus with either time or temperature. The sensory shelf life of the pizzas was approximately 5 d at 10°C and 6 d at 3°C. The pizzas were unacceptable after 7 d at either temperature.