The main objective of this experiment was to determine the most efficient S. typhimurium intervention method suitable for small scale industrial implementation. Ultimately, the specific intervention method used did not matter as no distinguishable differences were observed between inoculated carcasses that received different intervention treatments, a standard hot water rinse and 24 h chill step. A general intervention should be implemented following dehairing and evisceration because both processes present the possibility for re-contamination. The hot water (53ºC) sprayed at 70 psi was the most effective individual intervention but it was essential that the carcasses also be rinsed or receive some antimicrobial treatment after evisceration and chilled to achieve a near complete reduction of 8.0 Log CFU/cm2 S. typhimurium. Also, some caution should be heeded when applying high pressure sprays during swine slaughter as the jowl area was found to be the least accessible area to these treatments. The combination of various decontamination strategies during livestock slaughter is encouraged by the FSIS as they have been proven to reduce enteropathogen populations on carcasses (Fed. Register, 1995).
Salmonella spp. prevalence since HACCP was implemented has dropped mainly due to several meat and poultry establishments incorporating antimicrobial treatments during processing in order to meet FSIS performance standards (Rose et al., 2002). There is an abundance of research currently being conducted with the objective of finding the most efficient combination of antimicrobial treatments while in most cases, neglecting the significance of the chill step. The chill step had the greatest influence on the S. typhimurium strains used in this experiment.