The inactivation of Escherichia coli O157:H7 during pulsed electric field (PEF) treatment in a static chamber

2002 ◽  
Vol 19 (4) ◽  
pp. 351-361 ◽  
Author(s):  
S Ravishankar
Keyword(s):  
Escherichia Coli ◽  
Electric Field ◽  
Pulsed Electric Field ◽  
Escherichia Coli O157 ◽  
Static Chamber

Inactivation of Escherichia coli O157:H7, Listeria monocytogenes, and Lactobacillus leichmannii by Combinations of Ozone and Pulsed Electric Field

2001 ◽  
Vol 64 (6) ◽  
pp. 777-782 ◽  
Author(s):  
RAGIP UNAL ◽  
JIN-GAB KIM ◽  
AHMED E. YOUSEF
Keyword(s):  
Escherichia Coli ◽  
Listeria Monocytogenes ◽  
Electric Field ◽  
Pulsed Electric Field ◽  
Bactericidal Effect ◽  
Treatment Level ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Nonthermal Processing ◽  
Lactobacillus Leichmannii

Pulsed electric field (PEF) and ozone technologies are nonthermal processing methods with potential applications in the food industry. This research was performed to explore the potential synergy between ozone and PEF treatments against selected foodborne bacteria. Cells of Lactobacillus leichmannii ATCC 4797, Escherichia coli O157:H7 ATCC 35150, and Listeria monocytogenes Scott A were suspended in 0.1% NaCl and treated with ozone, PEF, and ozone plus PEF. Cells were treated with 0.25 to 1.00 μg of ozone per ml of cell suspension, PEF at 10 to 30 kV/cm, and selected combinations of ozone and PEF. Synergy between ozone and PEF varied with the treatment level and the bacterium treated. L. leichmannii treated with PEF (20 kV/cm) after exposure to 0.75 and 1.00 μg/ml of ozone was inactivated by 7.1 and 7.2 log10 CFU/ml, respectively; however, ozone at 0.75 and 1.00 μg/ml and PEF at 20 kV/cm inactivated 2.2, 3.6, and 1.3 log10 CFU/ml, respectively. Similarly, ozone at 0.5 and 0.75 μg/ml inactivated 0.5 and 1.8 log10 CFU/ml of E. coli, PEF at 15 kV/cm inactivated 1.8 log10 CFU/ml, and ozone at 0.5 and 0.75 μg/ml followed by PEF (15 kV/cm) inactivated 2.9 and 3.6 log10 CFU/ml, respectively. Populations of L. monocytogenes decreased 0.1, 0.5, 3.0, 3.9, and 0.8 log10 CFU/ml when treated with 0.25, 0.5, 0.75, and 1.0 μg/ml of ozone and PEF (15 kV/cm), respectively; however, when the bacterium was treated with 15 kV/cm, after exposure to 0.25, 0.5, and 0.75 μg/ml of ozone, 1.7, 2.0, and 3.9 log10 CFU/ml were killed, respectively. In conclusion, exposure of L. leichmannii, E. coli, and L. monocytogenes to ozone followed by the PEF treatment showed a synergistic bactericidal effect. This synergy was most apparent with mild doses of ozone against L. leichmannii.

Effects of pH, Temperature, and Pre–Pulsed Electric Field Treatment on Pulsed Electric Field and Heat Inactivation of Escherichia coli O157:H7

2003 ◽  
Vol 66 (5) ◽  
pp. 755-759 ◽  
Author(s):  
GULSUN AKDEMIR EVRENDILEK ◽  
Q. HOWARD ZHANG
Keyword(s):  
Escherichia Coli ◽  
Heat Treatment ◽  
Electric Field ◽  
Pulsed Electric Field ◽  
Heat Inactivation ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Effects Of Ph ◽  
Different Temperatures ◽  
Pulsed Electric Field Treatment

This investigation was undertaken to study the inactivation of Escherichia coli O157:H7 by pulsed electric field (PEF) treatment and heat treatment after exposure to different stresses. E. coli O157:H7 cells exposed to different pHs (3.6, 5.2, and 7.0 for 6 h), different temperatures (4, 35, and 40°C for 6 h), and different pre-PEF treatments (10, 15, and 20 kV/cm) were treated with PEFs (20, 25, and 30 kV/cm) or heat (60°C for 3 min). The results of these experiments demonstrated that a pH of 3.6 and temperatures of 4 and 40°C caused significant decreases in the inactivation of E. coli O157:H7 by PEF treatment and heat treatment (P < 0.05). Pre-PEF treatments, pHs of 5.2 and 7.0, and a temperature of 35°C, on the other hand, did not result in any resistance of E. coli O157:H7 cells to inactivation by PEF treatment and heat treatment (P > 0.05).

scholarly journals Proteomics-Based Mechanistic Investigation of Escherichia coli Inactivation by Pulsed Electric Field

2019 ◽  
Vol 10 ◽  
Author(s):  
Zhenyu Liu ◽  
Lingying Zhao ◽  
Qin Zhang ◽  
Nan Huo ◽  
Xiaojing Shi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Electric Field ◽  
Pulsed Electric Field ◽  
Mechanistic Investigation
Sign in / Sign up

Export Citation Format

Share Document