VALIDATION OF CHEMICAL AND NON-CHEMICAL ANTIMICROBIAL INTERVENTIONS APPLIED PRE- AND POST-CHILLING TO REDUCE MICROBIAL POPULATIONS IN BROILER CARCASSES A Thesis by VERONICA ALEJANDRA MOLINA

Validation of Chemical and Non-Chemical Antimicrobial Interventions Applied Preand Post-Chilling to Reduce Microbial Populations in Broiler Carcasses. (August 2007) Veronica Alejandra Molina, B.Sc., Zamorano Panamerican Agricultural University Chair of Advisory Committee: Dr. Marcos X. Sánchez-Plata Higher risks of food-borne illness associated with increased consumption of poultry products make it necessary to identify potential sources of contamination and apply intervention strategies that will prevent or minimize the risk of contamination during processing. This study investigated the effects of chemical and natural decontamination treatments including sprayed application of acidified calcium sulfate (ACS) in combination with -polylysine (EPL), dry-rubbing kosher salt coating and molten paraffin wax dipping application on microbial populations of broiler carcasses and parts. Treatments were evaluated for their effectiveness in reducing the numbers of artificially inoculated rifampicin resistant Salmonella Typhimurium strain NVSL 951776 on the skin surface of bone-in chicken breasts. General model procedures were used to find statistical differences (P<0.05) and separation of means was done with least square means using SAS 9.1. Chemical interventions (ACS + EPL) caused an overall reduction of ~0.65 CFU/ml of rifampicin resistant Salmonella Typhimurium populations in inoculated chicken breasts. Similar reductions were observed in validation experiments in whole carcasses when compared to post-eviscerated control samples as well as post chilled