title: A pilot plant scale evaluation of a new process aid for enhancing chlorine efficacy against pathogen survival and cross-contamination during produce wash.
abstract: Developing food safety intervention technology that can be readily adopted by the industry often requires test conditions that match as closely as possible to those of commercial food processing operations; yet biosafety risks inherent in pathogen studies constrain most experiments to laboratory settings. In this study, we report the first semi-commercial pilot-scale evaluation of a new process aid, T128, for its impact on enhancing the antimicrobial efficacy of chlorinated wash water against pathogen survival and cross-contamination. A non-pathogenic, BSL-1, strain of Escherichia coli O157:H7 was inoculated onto freshly harvested baby spinach leaves and washed with large amounts of freshly cut un-inoculated iceberg lettuce shreds in wash water with free chlorine periodically replenished, in the presence or absence of T128. Changes in water quality and pathogen survival and cross-contamination were monitored at every 2 min intervals for up to 36 min for each treatment during the wash operation. Results indicated that the use of T128 did not significantly (P>0.05) influence the rate of wash water deterioration, nor the pathogen populations remaining on the inoculated spinach leaves. However, in the absence of T128 (control), survival of E. coli O157:H7 in wash water and cross-contamination of un-inoculated lettuce frequently occurred when free chlorine in solution dropped below 1mg/l during the wash process. In contrast, the use of T128 significantly reduced the occurrence of E. coli O157:H7 surviving in wash water and of cross-contamination to un-inoculated shredded iceberg lettuce under the same operational conditions, suggesting that the application of T128 in a chlorine-based fresh produce sanitization system could increase the safety margin of process control on fresh-cut operations.
authors.affiliation: Environmental Microbial and Food Safety Laboratory, US Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, United States. Yaguang.Luo@ars.usda.gov
authors.forename: Yaguang
authors.initials: Y
authors.lastname: Luo
authors.forename: Xiangwu
authors.initials: X
authors.lastname: Nou
authors.forename: Patricia
authors.initials: P
authors.lastname: Millner
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.forename: Cangliang
authors.initials: C
authors.lastname: Shen
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Wu
authors.forename: Qin
authors.initials: Q
authors.lastname: Wang
authors.forename: Hao
authors.initials: H
authors.lastname: Feng
authors.forename: Dan
authors.initials: D
authors.lastname: Shelton
mesh_terms: D002712:Chlorides; D017606:Chlorine Compounds / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004202:Disinfectants / Q000494:pharmacology*; D004926:Escherichia coli; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development; D005506:Food Contamination / Q000517:prevention & control*; D005511:Food Handling / Q000379:methods; D059022:Food Safety; D018515:Plant Leaves; D010944:Plants; D018724:Spinacia oleracea / Q000382:microbiology; D014867:Water
chemical_list: D002712:Chlorides; D017606:Chlorine Compounds; D004202:Disinfectants; D014867:Water