title: Chlorine stabilizer T-128 enhances efficacy of chlorine against cross-contamination by E. coli O157:H7 and Salmonella in fresh-cut lettuce processing.
abstract: During fresh-cut produce processing, organic materials released from cut tissues can rapidly react with free chlorine in the wash solution, leading to the potential survival of foodborne bacterial pathogens, and cross-contamination when the free chlorine is depleted. A reported chlorine stabilizer, T-128, has been developed to address this problem. In this study, we evaluated the ability of T-128 to stabilize free chlorine in wash solutions in the presence of high organic loads generated by the addition of lettuce extract or soil. Under conditions used in this study, T-128 significantly (P<0.001) decreased the rate of free chlorine depletion at the presence of soil. T-128 also slightly decreased the rate of free chlorine depletion caused by the addition of lettuce extract in wash solution. Application of T-128 significantly reduced the survival of bacterial pathogens in wash solutions with high organic loads and significantly reduced the potential of cross-contamination, when contaminated and uncontaminated produce were washed together. However, T-128 did not enhance the efficacy of chlorinated wash solutions for microbial reduction on contaminated iceberg lettuce. Evaluation of several produce quality parameters, including overall visual appearance, package headspace O2 and CO2 composition, and lettuce electrolyte leakage, during 15 d of storage indicated that iceberg lettuce quality and shelf life were not negatively impacted by washing fresh-cut lettuce in chlorine solutions containing 0.1% T-128.
  
  
  CONCLUSIONS
  Reported chlorine stabilizer is shown to enhance chlorine efficacy against potential bacterial cross-contamination in the presence of high organic loads without compromising product quality and shelf life.
authors.affiliation: Environmental Microbial and Food Safety Laboratory, U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, USA. xiangwu.nou@ars.usda.gov
authors.forename: Xiangwu
authors.initials: X
authors.lastname: Nou
authors.forename: Yaguang
authors.initials: Y
authors.lastname: Luo
authors.forename: LaVonda
authors.initials: L
authors.lastname: Hollar
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Hao
authors.initials: H
authors.lastname: Feng
authors.forename: Patricia
authors.initials: P
authors.lastname: Millner
authors.forename: Daniel
authors.initials: D
authors.lastname: Shelton
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002245:Carbon Dioxide / Q000378:metabolism; D002713:Chlorine / Q000737:chemistry / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004355:Drug Stability; D004573:Electrolytes / Q000378:metabolism; D019453:Escherichia coli O157 / Q000187:drug effects*; D057140:Fast Foods / Q000382:microbiology*; D005519:Food Preservation; D006801:Humans; D007700:Kinetics; D018545:Lactuca / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D050296:Microbial Viability; D010100:Oxygen / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology; D011786:Quality Control; D012486:Salmonella typhimurium / Q000187:drug effects*; D012973:Sodium Hypochlorite / Q000737:chemistry / Q000494:pharmacology; D012987:Soil / Q000737:chemistry; D018724:Spinacia oleracea / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D004573:Electrolytes; D012987:Soil; D002245:Carbon Dioxide; D002713:Chlorine; D012973:Sodium Hypochlorite; D010100:Oxygen