Purpose: The objective of this study was to determine the efficacy of a nonflammable isopropyl alcohol quaternary ammonium formula (IPAQUAT) and carbon dioxide sanitizer system for reducing Salmonella spp. on food contact surfaces.
Methods: Coupons of stainless steel and conveyor belting material typically used in dry processing environments were spot-inoculated in the center of 5 x 5 cm coupons with approximately 10.0 logs CFU/ml of a six-strain cocktail of Salmonella spp. and subjected to a treatment of IPAQUAT formula. After treatments of 30 s, 1 or 5 min, wet coupons were swabbed for enumeration and recovery. Duplicate inoculated surfaces were soiled with a breadcrumb flour mixture and allowed to sit on the lab bench for a minimum of 16 h before IPAQUAT treatment of 30 s, 1 or 5 min and then swabbed for recovery. For clean and soiled surfaces, serial dilutions were prepared and pour plated using tryptic soy agar plates for recovery and Hektoen enteric agar for Salmonella confirmation.
Results: While approximately 7 logs CFU/coupon were recovered before treatment, an average of 1.2 logs CFU/coupon , 0.8 logs/coupon, 0.7 logs/coupon were recovered after 30 s, 1 or 5 min treatments, respectively, for both clean and soiled surfaces. Treatment of IPAQUAT for 30 s resulted in 5.8 log CFU/coupon reductions whereas, greater than 6.2 log CFU/coupon reductions were observed for treatment times of 1 and 5 min.
Significance: Therefore, IPAQUAT system reduced over 6 logs CFU/coupon of Salmonella spp. when applied for 1 min or more and would be an effective sanitation system for dry-processing environments.