Validation of sanitizer efficacy in commercial apple dump tanks using a Listeria monocytogenes surrogate

Le résumé fourni par la source

: Cross-contamination during postharvest apple dump tank processing presents a significant food safety risk. To mitigate this risk, chemical sanitizers such as chlorine and peroxyacetic acid (PAA) are commonly used, yet data on their practical anti- Listeria efficacy under commercial conditions remain limited. This study assessed the effectiveness of both sanitizers in mitigating cross-contamination of Enterococcus faecium NRRL B-2354, a surrogate for Listeria monocytogenes , during commercial apple dump tank operations at four packing facilities in Washington State. Initial assessments using commercial process water in a pilot-scale dump tank showed that 25-100 ppm free chlorine (FC) and 40-80 ppm PAA reduced E. faecium on inoculated apples during 2-5 min washes. Subsequent in-plant studies with 50 ppm FC and 60 ppm PAA revealed variable efficacy across facilities. A 2-5 min process using 50 ppm FC and 60 ppm PAA, respectively, reduced E. faecium by 0.9-1.9 and 1.2-2.2 log 10 CFU/apple on inoculated apples, with corresponding transfers of 1.7-3.6 and 1.6-3.3 log 10 CFU/apple to non-inoculated apples and residual levels of 0.1-0.8 log 10 CFU/250 mL in spent dump tank water. These findings provide valuable insights for apple packers on the practical efficacy of sanitizer-treated dump tank processing, underscoring the importance of maintaining effective sanitizer levels and monitoring water quality during commercial operations.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.