Validation of commercial processes for inactivation of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes on the surface of whole-muscle turkey jerky.

Three strips of turkey breast meat were separately inoculated with multistrain mixtures of Escherichia coli O157:H7, Salmonella Typhimurium, or Listeria monocytogenes and placed on the top, middle, and bottom levels of a loading rack. The strips on the rack were then loaded into a smokehouse and cooked-dried for either 2.5 or 3.5 h at 73.8 degrees C (165 degrees F) or 1.5 or 2.5 h at 82.2 degrees C (180 degrees F) with constant hickory smoking and without addition of humidity. Cooking-drying marinated turkey jerky at 73.8 degrees C (165 degrees F) or 82.2 degrees C (180 degrees F) resulted in a >or= 7.1 log(10) cfu/strip reduction of all 3 pathogens. For nonmarinated jerky strips that were inoculated with E. coli O157:H7 or L. monocytogenes and cooked-dried at 82.2 degrees C (180 degrees F), a reduction of >or= 7.4 log(10) cfu/strip was observed, whereas for strips that were inoculated with Salmonella, a reduction of >or= 6.8 log(10) cfu/strip was observed. Cooking-drying nonmarinated turkey breast strips at 73.8 degrees C (165 degrees F) for 3.5 h resulted in a reduction of ca. 7.1 to 7.6 log(10) cfu/strip for all 3 pathogens, whereas for strips that were cooked-dried for 2.5 h, a reduction of ca. 5.4 to 6.2 log(10) cfu/strip was observed. Only marinated turkey jerky that was cooked-dried for 3.5 h at 73.8 degrees C (165 degrees F) satisfied the USDA-FSIS standard of identity (moisture: protein <or= 0.75:1.0) or shelf-stability (water activity of <or= 0.80), or both, requirements for jerky.