scholarly journals Modeling the Inactivation of Intestinal Pathogenic Escherichia coli O157:H7 and Uropathogenic E. coli in Ground Chicken by High Pressure Processing and Thymol

2016 ◽  
Vol 7 ◽  
Author(s):  
Shih-Yung Chien ◽  
Shiowshuh Sheen ◽  
Christopher H. Sommers ◽  
Lee-Yan Sheen
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
High Pressure Processing ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Pathogenic Escherichia Coli

High-Pressure Resistance Variation of Escherichia coli O157:H7 Strains and Salmonella Serovars in Tryptic Soy Broth, Distilled Water, and Fruit Juice

2007 ◽  
Vol 70 (9) ◽  
pp. 2078-2083 ◽  
Author(s):  
BROOKE M. WHITNEY ◽  
ROBERT C. WILLIAMS ◽  
JOSEPH EIFERT ◽  
JOSEPH MARCY
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
Orange Juice ◽  
High Pressure Processing ◽  
Distilled Water ◽  
Escherichia Coli O157 ◽  
Bacterial Populations ◽  
E Coli ◽  
Log Reduction ◽  
Salmonella Serovars

The effect of high pressure on the log reduction of six strains of Escherichia coli O157:H7 and five serovars of Salmonella enterica was investigated in tryptic soy broth, sterile distilled water, and commercially sterile orange juice (for Salmonella) and apple cider (for E. coli). Samples were subjected to high-pressure processing treatment at 300 and 550 MPa for 2 min at 6°C. Samples were plated onto tryptic soy agar directly after pressurization and after being held for 24 h at 4°C. At 300 MPa, little effect was seen on E. coli O157:H7 strains, while Salmonella serovars varied in resistance, showing reductions between 0.26 and 3.95 log CFU/ml. At 550 MPa, E. coli O157:H7 strains exhibited a range of reductions (0.28 to 4.39 log CFU/ml), while most Salmonella populations decreased beyond the detection limit (>5-log CFU/ml reduction). The most resistant strains tested were E. coli E009 and Salmonella Agona. Generally, bacterial populations in fruit juices showed larger decreases than did populations in tryptic soy broth and distilled water. E. coli O157:H7 cultures held for 24 h at 4°C after treatment at 550 MPa showed a significant log decrease as compared with cultures directly after treatment (P ≤ 0.05), while Salmonella serovars did not show this significant decrease (P > 0.05). All Salmonella serovars tested in orange juice treated at 550 MPa for 2 min at 6°C and held for 24 h showed a >5-log decrease, while E. coli O157:H7 strains require a higher pressure, higher temperature, longer pressurization, or a chemical additive to achieve a 5-log decrease.

scholarly journals Lethality Prediction for Escherichia Coli O157:H7 and Uropathogenic E. coli in Ground Chicken Treated with High Pressure Processing and Trans-Cinnamaldehyde

2018 ◽  
Vol 83 (3) ◽  
pp. 740-749 ◽  
Author(s):  
Shiowshuh Sheen ◽  
Chi-Yun Huang ◽  
Rommel Ramos ◽  
Shih-Yung Chien ◽  
O. Joseph Scullen ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
High Pressure Processing ◽  
Escherichia Coli O157 ◽  
E Coli

Application of High Pressure Processing To Kill Escherichia coli O157 in Ready-to-Eat Meats

2008 ◽  
Vol 71 (11) ◽  
pp. 2182-2189 ◽  
Author(s):  
ALEXANDER O. GILL ◽  
HOSAHALLI S. RAMASWAMY
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
Hold Time ◽  
Foodborne Pathogen ◽  
Immunomagnetic Separation ◽  
High Pressure Processing ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Reflected Light ◽  
Additional Reduction

Uncooked ready-to-eat (RTE) meats have previously been identified as vehicles for the transmission of the foodborne pathogen Escherichia coli O157. In this study, the potential for high pressure processing (HPP) to kill E. coli O157 in two RTE meats (Hungarian salami and All Beef salami) was investigated. The RTE meats were inoculated with a five-strain cocktail of E. coli O157, vacuum packed, and then pressure treated at 600 MPa with a hold time of 3 min. Samples were stored at 15°C for 28 days. HPP initially reduced E. coli numbers on both RTE meats by greater than 4 log CFU/g. However, with enrichment and immunomagnetic separation we were able to recover E. coli O157 from the samples. During storage, the numbers of E. coli O157 increased on the All Beef samples but remained static on the Hungarian salami, which had a restrictive pH and water activity. Increasing the hold time to 6 or 9 min did not result in additional reduction of E. coli O157. The sensory appeal of the two products was not significantly changed by HPP as determined by a sensory panel (n = 50). Analysis of the reflected light parameters of luminance, green-red, and blue-yellow revealed no significant changes. The results of these experiments indicate that HPP has potential as a lethal treatment for E. coli O157 on RTE meats with minimal changes in consumer appeal.

Use of Nonpathogenic Escherichia coli Surrogates as Predictors of the Survival of Nontyphoidal Salmonella, non-O157 Shiga Toxin–Producing Escherichia coli, and Escherichia coli O157 Populations after High Hydrostatic Pressure Processing

2018 ◽  
Vol 81 (7) ◽  
pp. 1068-1072 ◽  
Author(s):  
DALE R. WOERNER ◽  
IFIGENIA GEORNARAS ◽  
JENNIFER N. MARTIN ◽  
KEITH E. BELK ◽  
GARY R. ACUFF ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
Shiga Toxin ◽  
Pathogenic Bacteria ◽  
Ground Beef ◽  
High Pressure Processing ◽  
Escherichia Coli O157 ◽  
Specific Level ◽  
E Coli ◽  
Pathogen Populations

ABSTRACT Validated surrogates are a useful tool for studying the response of pathogens to food safety interventions, but better surrogates are needed for studies using high pressure processing. Ground beef (85% lean, 15% fat) was inoculated separately with mixed cultures of Escherichia coli O157, non-O157 Shiga toxin–producing E. coli, nontyphoidal Salmonella, and nonpathogenic E. coli surrogate bacteria. The inoculated ground beef was subjected to high hydrostatic pressures of 200, 400, and 600 MPa for 4, 6, and 8 min at each pressure. High pressure processing at 200 MPa reduced the inoculated populations of the pathogenic bacteria by 0.9 to 1.8 log CFU/g, 400 MPa reduced the inoculated populations by 2.5 to 3.6 log CFU/g, and 600 MPa reduced the inoculated populations by 4.5 to 5.6 log CFU/g. The nonpathogenic E. coli surrogates were more resistant to the effects of high pressure processing than were the inoculated pathogen populations. This finding suggests that the nonpathogenic E. coli surrogates could be used as process control indicators for high pressure processing of ground beef to predict a specific level of pathogen reduction. The surviving populations of the potential surrogate bacteria were proportional to the surviving populations of the pathogenic bacteria. The models allow for an estimation of the potential surviving populations of the pathogenic bacteria based on quantitative results of the populations of the surrogate bacteria.

Survival of Escherichia coli O157:H7 during Storage in Pressure-Treated Orange Juice

1999 ◽  
Vol 62 (9) ◽  
pp. 1038-1040 ◽  
Author(s):  
M. LINTON ◽  
J. M. J. McCLEMENTS ◽  
M. F. PATTERSON
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
Orange Juice ◽  
Ambient Pressure ◽  
Storage Period ◽  
High Pressure Processing ◽  
Escherichia Coli O157 ◽  
Pressure Treatment ◽  
E Coli ◽  
Time Required

The effect of a high-pressure treatment on the survival of a pressure-resistant strain of Escherichia coli O157:H7 (NCTC 12079) in orange juice during storage at 3°C was investigated over the pH range of 3.4 to 5.0. The pH of shelf-stable orange juice was adjusted to 3.4, 3.6, 3.9, 4.5, and 5.0 and inoculated with 108 CFU ml−1 of E. coli O157:H7. The orange juice was then pressure treated at 400 MPa for 1 min at 10°C or was held at ambient pressure (as a control). Surviving E. coli O157: H7 cells were enumerated at 1-day intervals during a storage period of 25 days at 3°C. Survival of E. coli O157:H7 during storage was dependent on the pH of the orange juice. The application of high pressure prior to storage significantly increased the susceptibility of E. coli O157:H7 to high acidity. For example, after pressure treatment, the time required for a 5-log decrease in cell numbers was reduced from 13 to 3 days at pH 3.4, from 16 to 6 days at pH 3.6, and from >25 to 8 days at pH 3.9. It is evident that the use of high-pressure processing of orange juice in order to increase the juice's shelf-life and to inactivate pathogens has the added advantage that it sensitizes E. coli O157:H7 to the high acid conditions found in orange juice, which results in the survival of significantly fewer E. coli O157:H7 during subsequent refrigerated storage.

Inactivation of Escherichia coli O157:H7 in Ground Beef by Single-Cycle and Multiple-Cycle High-Pressure Treatments

2008 ◽  
Vol 71 (4) ◽  
pp. 811-815 ◽  
Author(s):  
PILAR MORALES ◽  
JAVIER CALZADA ◽  
MARTA ÁVILA ◽  
MANUEL NUÑEZ
Keyword(s):  
Escherichia Coli ◽  
High Pressure ◽  
Shear Force ◽  
Ground Beef ◽  
Escherichia Coli O157 ◽  
Single Cycle ◽  
E Coli ◽  
Beef Patties ◽  
Texture Parameters ◽  
Multiple Cycle

The effect of single- and multiple-cycle high-pressure treatments on the survival of Escherichia coli CECT 4972, a strain belonging to the O157:H7 serotype, in ground beef was investigated. Beef patties were inoculated with 107 CFU/g E. coli O157:H7, and held at 4°C for 20 h before high-pressure treatments. Reduction of the E. coli O157:H7 population by single-cycle treatments at 400 MPa and 12°C ranged from 0.82 log CFU/g for a 1-min cycle to 4.39 log CFU/g for a 20-min cycle. Multiple-cycle treatments were very effective, with four 1-min cycles at 400 MPa and 12°C reducing the E. coli O157:H7 population by 4.38 log CFU/g, and three 5-min cycles by 4.96 log CFU/g. The color parameter L* increased significantly with high-pressure treatments in the interior and the exterior of beef patties, whereas a* decreased in the interior, and b* increased in the exterior—changes that might diminish consumer acceptance of the product. Kramer shear force and energy were generally higher in pressurized than in control ground beef. Maximum values for these texture parameters, which corresponded to tougher patties, were reached after one 10-min cycle in the case of single-cycle treatments or two 5-min cycles in the case of multiple-cycle treatments. High-pressure treatments had no significant effect on Warner-Bratzler shear force.

scholarly journals Modelling Growth and Decline in a Two-Species Model System: Pathogenic Escherichia coli O157:H7 and Psychrotrophic Spoilage Bacteria in Milk

Foods ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 331 ◽  
Author(s):  
Emiliano J. Quinto ◽  
Juan M. Marín ◽  
Irma Caro ◽  
Javier Mateo ◽  
Donald W. Schaffner
Keyword(s):  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
Food Borne ◽  
Pathogenic Escherichia Coli ◽  
Spoilage Bacteria ◽  
Processing And Storage ◽  
And Storage ◽  
Natural Microbiota

Shiga toxin-producing Escherichia coli O157:H7 is a food-borne pathogen and the major cause of hemorrhagic colitis. Pseudomonas is the genus most frequent psychrotrophic spoilage microorganisms present in milk. Two-species bacterial systems with E. coli O157:H7, non-pathogenic E. coli, and P. fluorescens in skimmed milk at 7, 13, 19, or 25 °C were studied. Bacterial interactions were modelled after applying a Bayesian approach. No direct correlation between P. fluorescens’s growth rate and its effect on the maximum population densities of E. coli species was found. The results show the complexity of the interactions between two species in a food model. The use of natural microbiota members to control foodborne pathogens could be useful to improve food safety during the processing and storage of refrigerated foods.

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