INFLUENCE OF MODIFIED ATMOSPHERE PACKAGING ON GROWTH OF CLOSTRIDIUM-PERFRINGENS IN COOKED TURKEY

Clostridium perfringens containing samples of sterile ground turkey we re studied to assess growth under modified atmosphere conditions. Samp les were packaged under various atmospheres (CO2/O-2/N-2: 75/5/20, 75/ 10/15, 75/20/5, 25/20/55, 50/20/30), stored at 4, 15 and 28C, and samp led periodically for growth. Diluted samples were plated on Shahidi Fe rguson perfringens agar (Difco Laboratories, Detroit, MI) to determine vegetative cell counts. Temperature abuse (cyclic and static) of the turkey product was also investigated. The results showed that the grow th of C. perfringens was slowest under 25-50% CO2/20% O-2/balance N-2 at 15 and 28C. There was no growth at 4C for up to 28 days. Temperatur e abuse (28C storage) of refrigerated products for 8 h did not permit C. perfringens growth. Use of 25-50% CO2/20% O-2/balance N-2 may exten d the shelf-life of turkey, but in the absence of proper refrigeration , it cannot be relied upon to eliminate the risk of C. perfringens foo d poisoning.