Inactivation of Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes on stored iceberg lettuce by aqueous chlorine dioxide treatment.
Inactivation of Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes in iceberg lettuce by aqueous chlorine dioxide (ClO(2)) treatment was evaluated. Iceberg lettuce samples were inoculated with approximately 7 log CFU/g of E. coli O157:H7, S. typhimurium, and L. monocytogenes. Iceberg lettuce samples were then treated with 0, 5, 10, or 50 ppm ClO(2) solution and stored at 4 degrees C. Aqueous ClO(2) treatment significantly decreased the populations of pathogenic bacteria on shredded lettuce (P < 0.05). In particular, 50 ppm ClO(2) treatment reduced E. coli O157:H7, S. typhimurium, and L. monocytogenes by 1.44, 1.95, and 1.20 log CFU/g, respectively. The D(10)-values of E. coli O157:H7, S. typhimurium, and L. monocytogenes in shredded lettuce were 11, 26, and 42 ppm, respectively. The effect of aqueous ClO(2) treatment on the growth of pathogenic bacteria during storage was evaluated, and a decrease in the population size of these pathogenic bacteria was observed. Additionally, aqueous ClO(2) treatment did not affect the color of lettuce during storage. These results suggest that aqueous ClO(2) treatment can be used to improve the microbial safety of shredded lettuce during storage.
Kim
Yun-Jung
YJ
Department of Food Science and Technology, Chungnam National University, Daejeon, 305-764, Korea.
Lee
Seung-Hwan
SH
Park
Jiyong
J
Park
Jonghyun
J
Chung
Myongsoo
M
Kwon
Kisung
K
Chung
Kyungsook
K
Won
Misun
M
Song
Kyung Bin
KB
D017606:Chlorine Compounds / Q000494:pharmacology*; D004202:Disinfectants / Q000494:pharmacology*; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000528:radiation effects; D005511:Food Handling; D005638:Fruit / Q000382:microbiology / Q000592:standards; D018545:Lactuca / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000528:radiation effects; D010087:Oxides / Q000494:pharmacology*; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000528:radiation effects; D014466:Ultraviolet Rays; D014675:Vegetables / Q000382:microbiology / Q000592:standards
D017606:Chlorine Compounds; D004202:Disinfectants; D010087:Oxides; C025109:chlorine dioxide