Thermal inactivation D- and z-values of multidrug-resistant and non-multidrug-resistant Salmonella serotypes and survival in ground beef exposed to consumer-style cooking.

摘要: There has been speculation that multidrug-resistant (MDR) strains are generated by subtherapeutic antibiotic use in food animals and such result increased resistance to lethality processes as heat irradiation. The objective of this study was evaluate the 20 strains, namely an MDR a non-multidrug-resistant (NMDR) strain each 10 Salmonella serotypes isolated from cattle or environments. NMDR studied included Montevideo, Typhimurium, Anatum, Muenster, Newport, Mbandaka, Dublin, Reading, Agona, Give. For phase I, stationary-phase cultures were aliquoted into sterile capillary tubes immersed temperature-controlled water bath at 55, 60, 65, 70 degrees C for appropriate times. Survivor curves plotted temperature, best-fit linear regression derived temperature. D-values (decimal reduction times) z-values (changes temperature required change D-values) calculated strain. Although there no overall significant difference serotypes, generally appeared have slightly higher than especially 55 60 C. highest relative (highest z-values) exhibited Anatum. Notably, Agona similar Anatum had all four temperatures. II, three (regardless profile) with their drug-resistant counterparts selected thermal inactivation ground beef patties cooked endpoint able survive internal 71 Results these studies suggest drug does not affect serotype is important consideration risk assessment pathogen regard survival cooking