Red meat is associated with Salmonella outbreaks resulting in negative impacts for the processing industry. Little work has been reported on the use of dry heat as opposed to moist heat against Salmonella on red meat. We determined the effect of drying at 25°C and dry heat at 70°C with ~10% relative humidity (RH) for 1 h against eleven Salmonella strains of multiple serovars on beef, lamb, goat, and rubber as an inert surface. Each strain at ~108 cfu/ml was inoculated (100ul) onto ±1g (1cm2) of each surface and allowed to attach for 15 min in a microcentrifuge tube. Samples were then exposed to 70°C and 25°C with ~10% RH in a heating block. Surviving Salmonella numbers on surfaces were enumerated on a thin layer medium. If numbers were below the limit of detection (LOD), (2.01 log cfu/cm2), Salmonella cells were enriched before plating to determine the presence of viable cells. Water loss (%) from meat after at 25°C and 70°C was determined. Whole genomes of Salmonella were interrogated to identify the presence/absence of stress response genes (n=30) related to dry heat which may contribute to the survival of Salmonella. The survival of Salmonella at 25°C was significantly higher across all surfaces (~6.09–7.91 log cfu/cm2) as compared to 70°C (~3.66–6.33 log cfu/cm2). On rubber, numbers of Salmonella were <LOD at 70°C. Water loss at 70°C (~17.72–19.89%) was significantly higher as compared to 25°C (~2.98–4.11%). Salmonella was not detected on rubber while survival occurred on all red meat at 70°C, suggesting its protective effect against the effect of heat. All Salmonella strains carried 30 stress response genes which likely contributed to its survival. A multi-antibiotic resistant S. Typhimurium 2470 exhibited an increase in heat resistance at 70°C on beef and lamb as compared to other strains. Our work shows that dry heat at 70°C for 1 h against Salmonella on red meat is not a practical approach for effectively reducing or eliminating them from red meat.

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