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Rios EA, Ribeiro DCS, Otero A, Rodríguez-Calleja JM. A hurdle strategy based on the combination of non-thermal treatments to control diarrheagenic E. coli in cheese. Int J Food Microbiol 2024; 425:110859. [PMID: 39173289 DOI: 10.1016/j.ijfoodmicro.2024.110859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 07/23/2024] [Accepted: 08/08/2024] [Indexed: 08/24/2024]
Abstract
This study aimed to assess the efficacy of a multi-hurdle process combining mild High Hydrostatic Pressure (HHP) treatments and Thyme Oil (TO) edible films as a non-thermal method to combat pathogenic E. coli (aEPEC and STEC) in raw cow's-milk cheese stored at 7 °C and packaged under modified atmosphere. Changes in headspace atmosphere of cheese packs and treatment effects on Lactic Acid Bacteria (LAB) counts and diarrheagenic E. coli strains (aEPEC and STEC) were evaluated over a 28 d storage period. The results demonstrated that the combined treatment exhibited the most significant antimicrobial effect against both strains compared to individual treatments, achieving reductions of 4.30 and 4.80 log cfu/g after 28 d of storage for aEPEC and STEC, respectively. Notably, the synergistic effect of the combination treatment resulted in the complete inactivation of intact cells for STEC and nearly completed inactivation for aEPEC by the end of the storage period. These findings suggest that the combination of HHP with selected hurdles could effectively enhance microbial inactivation capacity, offering promising alternatives for improving cheese safety without affecting the starter microbiota.
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Affiliation(s)
- Edson A Rios
- National Institute of Science and Technology for the Dairy Production Chain (INCT-Leite), Paraná, Brazil
| | - Daniela C S Ribeiro
- Department of Food Hygiene and Food Technology, Veterinary Faculty, Universidad de León, Spain
| | - Andrés Otero
- Department of Food Hygiene and Food Technology, Veterinary Faculty, Universidad de León, Spain; Institute of Food Science and Technology, Universidad de León, 24071 León, Spain
| | - Jose M Rodríguez-Calleja
- Department of Food Hygiene and Food Technology, Veterinary Faculty, Universidad de León, Spain; Institute of Food Science and Technology, Universidad de León, 24071 León, Spain.
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2
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The Effect of High-Pressure Processing on the Survival of Non-O157 Shiga Toxin-Producing Escherichia coli in Steak Tartare: The Good- or Best-Case Scenario? Microorganisms 2023; 11:microorganisms11020377. [PMID: 36838342 PMCID: PMC9964116 DOI: 10.3390/microorganisms11020377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/24/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
Samples of steak tartare were artificially contaminated with a cocktail of Shiga toxin-producing Escherichia coli (STEC) O91, O146, O153, and O156 to the level of 3 log and 6 log CFU/g. Immediately after vacuum packing, high-pressure processing (HPP) was performed at 400 or 600 MPa/5 min. Some of the samples not treated with HPP were cooked under conditions of 55 °C for 1, 3, or 6 h. HPP of 400 MPa/5 min resulted in a 1-2 log reduction in the STEC count. In contrast, HPP of 600 MPa/5 min led to the elimination of STEC even when inoculated to 6 log CFU/g. Nevertheless, sub-lethally damaged cells were resuscitated after enrichment, and STEC was observed in all samples regardless of the pressure used. STEC was not detected in the samples cooked in a 55 °C water bath for 6 h, even after enrichment. Unfortunately, the temperature of 55 °C negatively affected the texture of the steak tartare. Further experiments are necessary to find an optimal treatment for steak tartare to assure its food safety while preserving the character and quality of this attractive product.
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3
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Sheen S, Huang CY, Chuang S. Synergistic effect of high hydrostatic pressure, allyl isothiocyanate, and acetic acid on the inactivation and survival of pathogenic Escherichia coli in ground chicken. J Food Sci 2022; 87:5042-5053. [PMID: 36181370 DOI: 10.1111/1750-3841.16346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 08/17/2022] [Accepted: 09/05/2022] [Indexed: 11/27/2022]
Abstract
Meat and poultry are prone to contamination with foodborne pathogens sourced from the livestock or introduced from the processing environments. In this study, for retention of meat quality while assuring microbial food safety, mild levels of high hydrostatic pressure were hurdled with food-grade additives (i.e., allyl isothiocyanate [AITC] and acetic acid [AA], functioned as antimicrobials) to inactivate pathogenic Escherichia coli in ground chicken. The reductions of Shiga toxin-producing E. coli (STEC) O157:H7 and uropathogenic E. coli (UPEC) were described as a function of high hydrostatic pressure (200-350 MPa), process-holding time (10-25 min), AITC concentration (0.05-0.20% w/w), and AA concentration (0.10--0.30% w/w) using a full factorial design. The antimicrobials had little influence on bacterial inactivation without high pressure. Without the antimicrobials, a high-pressure treatment at 300 MPa and 4°C for 15 min reduced E. coli O157:H7 and UPEC by 1.52 and 2.52 log, respectively. A 5-log reduction was achieved when AITC and AA were combined with high pressure, indicating a synergistic effect. The survivors were further reduced to below the detection limit of 1 log CFU/g after subsequent storage tests at 4 and 10°C for 10 days. The STEC O157:H7 was found slightly more resistant than UPEC in our test matrix. The developed models showed good fits with experimental data (R2 > 0.95 for linear models; Pr > F (<0.0001) for dimensionless nonlinear models); which may help processors find/optimize the processing parameters to achieve target foodborne pathogens reduction for food safety requirement. PRACTICAL APPLICATION: Models were developed to predict the inactivation of pathogenic Escherichia coli in ground chicken by high-pressure processing (HPP) in combination with natural antimicrobial compounds. These models can be used to estimate/determine the HPP operation parameters and antimicrobial usage levels (i.e., allyl isothiocyanate and acetic acid) needed to achieve a specific microbial log reduction within the selected factor ranges. The operation parameters and clean-label ingredients are of interest in the food industry, which may benefit from the application of the models in achieving microbial safety, process optimization, and operation cost reduction.
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Affiliation(s)
- Shiowshuh Sheen
- Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Wyndmoor, Pennsylvania, USA
| | - Chi-Yun Huang
- Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Shihyu Chuang
- Department of Food Science, University of Massachusetts, Amherst, Massachusetts, USA
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4
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Rey MDLÁ, Rodriguez Racca A, Rossi Ribeiro L, Dos Santos Cruz F, Cap M, Mozgovoj MV, Cristianini M, Vaudagna SR. High‐pressure processing treatment of beef burgers: Effect on
Escherichia coli
O157 inactivation evaluated by plate count and PMA‐qPCR. J Food Sci 2022; 87:2324-2336. [DOI: 10.1111/1750-3841.16179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/31/2022] [Accepted: 04/20/2022] [Indexed: 11/27/2022]
Affiliation(s)
- María de los Ángeles Rey
- Instituto Nacional de Tecnología Agropecuaria (INTA) Instituto Tecnología de Alimentos Buenos Aires Argentina
- Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA‐CONICET) Buenos Aires Argentina
| | - Anabel Rodriguez Racca
- Instituto Nacional de Tecnología Agropecuaria (INTA) Instituto Tecnología de Alimentos Buenos Aires Argentina
- Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA‐CONICET) Buenos Aires Argentina
| | - Luma Rossi Ribeiro
- Department of Food Engineering and Technology, School of Food Engineering University of Campinas (UNICAMP) Campinas Brazil
- Quality and Safety of food and feed, Department of Horticultural Engineering Leibniz Institute for Agricultural Engineering and Bioeconomy Potsdam Germany
| | - Fabiano Dos Santos Cruz
- Department of Food Engineering and Technology, School of Food Engineering University of Campinas (UNICAMP) Campinas Brazil
| | - Mariana Cap
- Instituto Nacional de Tecnología Agropecuaria (INTA) Instituto Tecnología de Alimentos Buenos Aires Argentina
- Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA‐CONICET) Buenos Aires Argentina
| | - Marina Valeria Mozgovoj
- Instituto Nacional de Tecnología Agropecuaria (INTA) Instituto Tecnología de Alimentos Buenos Aires Argentina
- Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA‐CONICET) Buenos Aires Argentina
| | - Marcelo Cristianini
- Department of Food Engineering and Technology, School of Food Engineering University of Campinas (UNICAMP) Campinas Brazil
| | - Sergio Ramón Vaudagna
- Instituto Nacional de Tecnología Agropecuaria (INTA) Instituto Tecnología de Alimentos Buenos Aires Argentina
- Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables (UEDD INTA‐CONICET) Buenos Aires Argentina
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5
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High pressure processing of raw meat with essential oils-microbial survival, meat quality, and models: A review. Food Control 2022. [DOI: 10.1016/j.foodcont.2021.108529] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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6
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Martínez Bernié I, Mussio P, Jorcin S, Rajchman M, López-Pedemonte T. Application of high hydrostatic pressure for the reduction of STEC on raw ground beef patties and its impact on physicochemical properties: pH and color. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.112126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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7
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Wang L, Kong X, Jiang Y. Recovery of high pressure processing (HPP) induced injured Escherichia coli O157:H7 inhibited by Lactobacillus sakei on vacuum-packed ground beef. FOOD BIOSCI 2021. [DOI: 10.1016/j.fbio.2021.100928] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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8
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Lee H, Shahbaz HM, Yang J, Jo MH, Kim JU, Yoo S, Kim SH, Lee D, Park J. Effect of high pressure processing combined with lactic acid bacteria on the microbial counts and physicochemical properties of uncooked beef patties during refrigerated storage. J FOOD PROCESS PRES 2021. [DOI: 10.1111/jfpp.15345] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hyunah Lee
- Department of Biotechnology Yonsei University Seoul South Korea
| | - Hafiz Muhammad Shahbaz
- Department of Food Science and Human Nutrition University of Veterinary and Animal Sciences Lahore Pakistan
| | - Jaekyung Yang
- Department of Biotechnology Yonsei University Seoul South Korea
| | - Mun Hui Jo
- Department of Biotechnology Yonsei University Seoul South Korea
| | - Jeong Un Kim
- Department of Biotechnology Yonsei University Seoul South Korea
| | - Sungyul Yoo
- Nutrex Technology Co., Ltd. Seongnam South Korea
| | - Sung Han Kim
- Nutrex Technology Co., Ltd. Seongnam South Korea
| | - Dong‐Un Lee
- Department of Food Science and Technology Chung‐Ang University Anseong South Korea
| | - Jiyong Park
- Department of Biotechnology Yonsei University Seoul South Korea
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Abstract
Abstract
Purpose of Review
The market for minimally processed products is constantly growing due to consumer demand. Besides food safety and increased shelf life, nutritional value and sensory appearance also play a major role and have to be considered by the food processors. Therefore, the purpose of the review was to summarize recent knowledge about important alternative non-thermal physical technologies, including both those which are actually applied (e.g. high-pressure processing and irradiation) and those demonstrating a high potential for future application in raw meat decontamination (e.g. pulsed light UV-C and cold plasma treatment). The evaluation of the methods is carried out with respect to efficiency, preservation of food quality and consumer acceptance.
Recent Findings
It was evident that significantly higher bacterial reductions are achieved with gamma-ray, electron beam irradiation and high pressure, followed by pulsed light, UV-C and cold plasma, with ultrasound alone proving the least effective. As a limitation, it must be noted that sensory deviations may occur and that legal approvals may have to be applied for.
Summary
In summary, it can be concluded that physical methods have the potential to be used for decontamination of meat surfaces in addition to common hygiene measures. However, the aim of future research should be more focused on the combined use of different technologies to further increase the inactivation effects by keeping meat quality at the same time.
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10
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Zhou S, Sheen S, Zhao G, Chuang S, Liu L. Prediction of Salmonella inactivation in sliced tomato subject to high pressure processing and trans-cinnamaldehyde treatment using selective and non-selective growth media for survival evaluations. Food Control 2020. [DOI: 10.1016/j.foodcont.2020.107441] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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11
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Li H, Sun X, Liao X, Gänzle M. Control of pathogenic and spoilage bacteria in meat and meat products by high pressure: Challenges and future perspectives. Compr Rev Food Sci Food Saf 2020; 19:3476-3500. [PMID: 33337070 DOI: 10.1111/1541-4337.12617] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 07/10/2020] [Accepted: 07/19/2020] [Indexed: 01/18/2023]
Abstract
High-pressure processing is among the most widely used nonthermal intervention to reduce pathogenic and spoilage bacteria in meat and meat products. However, resistance of pathogenic bacteria strains in meats at the current maximum commercial equipment of 600 MPa questions the ability of inactivation by its application in meats. Pathogens including Escherichia coli, Listeria, and Salmonelle, and spoilage microbiota including lactic acid bacteria dominate in raw meat, ready-to-eat, and packaged meat products. Improved understanding on the mechanisms of the pressure resistance is needed for optimizing the conditions of pressure treatment to effectively decontaminate harmful bacteria. Effective control of the pressure-resistant pathogens and spoilage organisms in meats can be realized by the combination of high pressure with application of mild temperature and/or other hurdles including antimicrobial agents and/or competitive microbiota. This review summarized applications, mechanisms, and challenges of high pressure on meats from the perspective of microbiology, which are important for improving the understanding and optimizing the conditions of pressure treatment in the future.
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Affiliation(s)
- Hui Li
- Institute of Quality Standard and Testing Technology for Agro-Products, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaohong Sun
- College of Food and Biological Engineering, Qiqihar University, Qiqihar, Heilongjiang, China
| | - Xiaojun Liao
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China
| | - Michael Gänzle
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada
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12
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Singh M, Novoa Rama E, Kataria J, Leone C, Thippareddi H. Emerging Meat Processing Technologies for Microbiological Safety of Meat and Meat Products. MEAT AND MUSCLE BIOLOGY 2020. [DOI: 10.22175/mmb.11180] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
A consumer trend toward convenient, minimally processed meat products has exerted tremendous pressure on meat processors to ensure the safety of meat and meat products without compromising product quality and the meeting of consumer demands. This has led to challenges in developing and implementing novel processing technologies as the use of newer technologies may affect consumer choices and opinions of meat and meat products. Novel technologies adopted by the meat industry for controlling foodborne pathogens of significant public health implications, gaps in the technologies, and the need for scaling up technologies that have been proven to be successful in research settings or at the pilot scale will be discussed. Novel processing technologies in the meat industry warrant microbiological validation prior to becoming commercially viable options and enacting infrastructural changes. This review presents the advantages and shortcomings of such technologies and provides an overview of technologies that can be successfully implemented and streamlined in existing processing environments.
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13
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Effect of Food Microstructure on Calcium Infusion Under High Pressure. FOOD ENGINEERING REVIEWS 2020. [DOI: 10.1007/s12393-020-09225-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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14
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Porto-Fett ACS, Shane LE, Shoyer BA, Osoria M, Jung Y, Luchansky JB. Inactivation of Shiga Toxin-Producing Escherichia coli and Listeria monocytogenes within Plant versus Beef Burgers in Response to High Pressure Processing. J Food Prot 2020; 83:865-873. [PMID: 32027738 DOI: 10.4315/jfp-19-558] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 01/15/2020] [Indexed: 11/11/2022]
Abstract
ABSTRACT We evaluated high pressure processing to lower levels of Shiga toxin-producing Escherichia coli (STEC) and Listeria monocytogenes inoculated into samples of plant or beef burgers. Multistrain cocktails of STEC and L. monocytogenes were separately inoculated (∼7.0 log CFU/g) into plant burgers or ground beef. Refrigerated (i.e., 4°C) or frozen (i.e., -20°C) samples (25 g each) were subsequently exposed to 350 MPa for up to 9 or 18 min or 600 MPa for up to 4.5 or 12 min. When refrigerated plant or beef burger samples were treated at 350 MPa for up to 9 min, levels of STEC were reduced by ca. 0.7 to 1.3 log CFU/g. However, when refrigerated plant or beef burger samples were treated at 350 MPa for up to 9 min, levels of L. monocytogenes remained relatively unchanged (ca. ≤0.3-log CFU/g decrease) in plant burger samples but were reduced by ca. 0.3 to 2.0 log CFU/g in ground beef. When refrigerated plant or beef burger samples were treated at 600 MPa for up to 4.5 min, levels of STEC and L. monocytogenes were reduced by ca. 0.7 to 4.1 and ca. 0.3 to 5.6 log CFU/g, respectively. Similarly, when frozen plant and beef burger samples were treated at 350 MPa up to 18 min, reductions of ca. 1.7 to 3.6 and ca. 0.6 to 3.6 log CFU/g in STEC and L. monocytogenes numbers, respectively, were observed. Exposure of frozen plant or beef burger samples to 600 MPa for up to 12 min resulted in reductions of ca. 2.4 to 4.4 and ca. 1.8 to 3.4 log CFU/g in levels of STEC and L. monocytogenes, respectively. Via empirical observation, pressurization did not adversely affect the color of plant burger samples, whereas appreciable changes in color were observed in pressurized ground beef. These data confirm that time and pressure levels already validated for control of STEC and L. monocytogenes in ground beef will likely be equally effective toward these same pathogens in plant burgers without causing untoward effects on product color. HIGHLIGHTS
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Affiliation(s)
- Anna C S Porto-Fett
- U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA (ORCID: https://orcid.org/0000-0002-2689-6402 [A.C.S.P.F.]; https://orcid.org/0000-0003-2377-8651 [J.B.L.])
| | - Laura E Shane
- U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA (ORCID: https://orcid.org/0000-0002-2689-6402 [A.C.S.P.F.]; https://orcid.org/0000-0003-2377-8651 [J.B.L.])
| | - Bradley A Shoyer
- U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA (ORCID: https://orcid.org/0000-0002-2689-6402 [A.C.S.P.F.]; https://orcid.org/0000-0003-2377-8651 [J.B.L.])
| | - Manuela Osoria
- U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA (ORCID: https://orcid.org/0000-0002-2689-6402 [A.C.S.P.F.]; https://orcid.org/0000-0003-2377-8651 [J.B.L.])
| | - Yangjin Jung
- U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA (ORCID: https://orcid.org/0000-0002-2689-6402 [A.C.S.P.F.]; https://orcid.org/0000-0003-2377-8651 [J.B.L.])
| | - John B Luchansky
- U.S. Department of Agriculture, Agricultural Research Service, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA (ORCID: https://orcid.org/0000-0002-2689-6402 [A.C.S.P.F.]; https://orcid.org/0000-0003-2377-8651 [J.B.L.])
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Porto-Fett ACS, Jackson-Davis A, Kassama LS, Daniel M, Oliver M, Jung Y, Luchansky JB. Inactivation of Shiga Toxin-Producing Escherichia coli in Refrigerated and Frozen Meatballs Using High Pressure Processing. Microorganisms 2020; 8:E360. [PMID: 32138184 PMCID: PMC7142488 DOI: 10.3390/microorganisms8030360] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 11/16/2022] Open
Abstract
High pressure processing (HPP) was evaluated to inactivate Shiga toxin-producing Escherichia coli (STEC) in raw meatballs. Ground meat (>90% lean) was inoculated (ca. 7.0 log CFU/g) with a rifampicin-resistant cocktail of eight STEC strains (O26:H11, O45:H2, O103:H2, O104:H4, O111:H-, O121:H19, O145:NM, and O157:H7). Inoculated ground beef, ground veal, or a mixture of ground beef, pork, and veal were separately mixed with liquid whole eggs and seasonings, shaped by hand into meatballs (40 g each), and stored at -20 or at 4 °C for at least 18 h. Samples were then exposed to 400 or 600 MPa for 0 to 18 min. There were no differences (p > 0.05) in pathogen reduction related to the species of meat used or for meatballs that were refrigerated (0.9 to 2.9 log CFU/g) compared to otherwise similar meatballs that were stored frozen (1.0 to 3.0 log CFU/g) prior to HPP treatment. However, less time was needed to achieve a ≥ 2.0 log CFU/g reduction at 600 MPa (1 to 3 min) compared to 400 MPa (at least 9 min). This work provides new and practically useful information on the use of HPP to inactivate STEC in raw meatballs.
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Affiliation(s)
- Anna C. S. Porto-Fett
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 19038, USA; (Y.J.); (J.B.L.)
| | - Armitra Jackson-Davis
- Department of Food and Animal Sciences, Alabama Agricultural and Mechanical University, 4900 Meridian St. N, Normal, AL 35762, USA; (A.J.-D.); (L.S.K.); (M.D.); (M.O.)
| | - Lamin S. Kassama
- Department of Food and Animal Sciences, Alabama Agricultural and Mechanical University, 4900 Meridian St. N, Normal, AL 35762, USA; (A.J.-D.); (L.S.K.); (M.D.); (M.O.)
| | - Marciauna Daniel
- Department of Food and Animal Sciences, Alabama Agricultural and Mechanical University, 4900 Meridian St. N, Normal, AL 35762, USA; (A.J.-D.); (L.S.K.); (M.D.); (M.O.)
| | - Michelle Oliver
- Department of Food and Animal Sciences, Alabama Agricultural and Mechanical University, 4900 Meridian St. N, Normal, AL 35762, USA; (A.J.-D.); (L.S.K.); (M.D.); (M.O.)
| | - YangJin Jung
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 19038, USA; (Y.J.); (J.B.L.)
| | - John B. Luchansky
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, PA 19038, USA; (Y.J.); (J.B.L.)
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16
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Liu L, Xiao X, Li K, Li X, Shi B, Liao X. Synthesis of Catechin-Rare Earth Complex with Efficient and Broad-Spectrum Anti-Biofilm Activity. Chem Biodivers 2020; 17:e1900734. [PMID: 31981410 DOI: 10.1002/cbdv.201900734] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 01/24/2020] [Indexed: 11/12/2022]
Abstract
Biofilm is the crucial reason of clinical infections. Herein, green tea based polyphenol (catechin) and rare earth (RE) metal ions were employed for the preparation of catechin-RE complexes with significant anti-biofilm properties. The complexes were characterized by FT-IR, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and dynamic light scattering (DLS), which suggested that catechin coordinated with RE3+ through its ortho phenolic hydroxy groups. The prepared catechin-RE showed significant effects in anti-biofilm growth against P. aeruginosa (Gram-negative bacteria), S. sciuri (Gram-positive bacteria), and A. niger (fungi), which significantly exceeded the utilization of catechin or RE3+ . Morphological observations indicated that catechin supplied cell affinity to transfer RE3+ and helped to damage cell membrane, which act as a carrier to exert cytotoxicity of RE3+ to realize anti-biofilm. Differential gene expression analysis described gene expression changes induced by catechin-RE, including 56, 272 and 2160 downregulated genes for P. aeruginosa, S. sciuri and A. niger, respectively, which suggested critical changes in cellular metabolism, growth and other processes. These results illustrate the outstanding superiority of catechin-RE complexes in anti-infection aspect, i. e., the green tea based rare earth complexes are promising candidates for anti-biofilm applications to address serious challenges in the prevention of multiple infections.
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Affiliation(s)
- Lu Liu
- Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu, 610065, P. R. China
| | - Xiao Xiao
- Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu, 610065, P. R. China.,National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu, 610065, P. R. China
| | - Ke Li
- Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu, 610065, P. R. China.,National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu, 610065, P. R. China
| | - Xia Li
- Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu, 610065, P. R. China
| | - Bi Shi
- Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu, 610065, P. R. China.,National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu, 610065, P. R. China
| | - Xuepin Liao
- Department of Biomass Chemistry and Engineering, Sichuan University, Chengdu, 610065, P. R. China.,National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu, 610065, P. R. China
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17
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Chen L, Zhao X, Wu J, Liu Q, Pang X, Yang H. Metabolic characterisation of eight Escherichia coli strains including "Big Six" and acidic responses of selected strains revealed by NMR spectroscopy. Food Microbiol 2019; 88:103399. [PMID: 31997756 DOI: 10.1016/j.fm.2019.103399] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 11/24/2019] [Accepted: 12/07/2019] [Indexed: 12/20/2022]
Abstract
The metabolic diversity of Escherichia coli strains (non-pathogenic E. coli ATCC 25922, and pathogenic E. coli O157:H7, O26:H11, O45:H2, O103:H11, O111, O121:H19, and O145) was tested using nuclear magnetic resonance. Based on two representative two-dimensional 1H-13C spectra, 38 metabolites were identified in E. coli intracellular samples. Principal component analysis indicated that metabolites including lysine, arginine, α-ketoglutaric acid, adenosine, and fumaric acid were responsible for the separation of E. coli ATCC 25922. Relatively large metabolic differences between ATCC 25922 and the pathogenic strains were recoded. The most varied pairwise group (ATCC 25922 vs. O26:H11) was further analysed. The screened metabolites and enrichment pathway tests revealed different amino acid metabolism and higher requirement for energy production in the pathogenic strains. The acidic responses of the selected strains were further tested. The in vitro and in vivo inactivation kinetics, morphological changes, and protein leakage showed higher acid tolerance of E. coli O26:H11. Metabolic analysis of the two strains under acidic stress revealed alternative metabolites and pathways in the two groups. Pathogenic O26:H11 was characterised by higher energy production and amino acid metabolism (lysine and glutamic acid). Real-time PCR tests confirmed that glutamic acid dependent decarboxylase/antiporter system was the major acid resistance mechanism.
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Affiliation(s)
- Lin Chen
- Department of Food Science and Technology, National University of Singapore, Singapore, 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, PR China
| | - Xue Zhao
- Department of Food Science and Technology, National University of Singapore, Singapore, 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, PR China
| | - Ji'en Wu
- Setsco Services Pte., Ltd., Singapore, 608925, Singapore
| | - Qin Liu
- Department of Food Science and Technology, National University of Singapore, Singapore, 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, PR China
| | - Xinyi Pang
- Department of Food Science and Technology, National University of Singapore, Singapore, 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, PR China
| | - Hongshun Yang
- Department of Food Science and Technology, National University of Singapore, Singapore, 117542, Singapore; National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Suzhou, Jiangsu, 215123, PR China.
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18
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Salazar JK, Natarajan V, Stewart D, Warren J, Gonsalves LJ, Mhetras T, Tortorello ML. Fate of Listeria monocytogenes in Ready-to-Eat Refrigerated Dips Treated with High Pressure Processing. J Food Prot 2019; 82:1320-1325. [PMID: 31310168 DOI: 10.4315/0362-028x.jfp-18-550] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Various outbreaks and recalls have been associated with Listeria monocytogenes contamination of ready-to-eat (RTE) food products, including dips. High pressure processing (HPP) is useful for reducing levels of bacteria in many RTE food products, but its efficacy for reduction of pathogens in RTE dips is not well understood. In this study, laboratory-prepared hummus, tahini, baba ghanoush, guacamole, and pesto were initially treated with HPP at 350 MPa for up to 240 s to assess L. monocytogenes inactivation and determine D-values. D350 MPa-values in hummus, guacamole, and baba ghanoush were 105.3, 71.3, and 34.0 s, respectively. No significant reduction in L. monocytogenes levels was observed in tahini or pesto at 350 MPa for 240 s or after additional treatment for up to 600 s at 600 MPa (P > 0.05). Overall, the results of this study highlight the efficacy of HPP for reducing L. monocytogenes levels in certain RTE dips and but not in others.
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Affiliation(s)
- Joelle K Salazar
- 1 U.S. Food and Drug Administration, Division of Food Processing Science, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Vidya Natarajan
- 1 U.S. Food and Drug Administration, Division of Food Processing Science, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Diana Stewart
- 1 U.S. Food and Drug Administration, Division of Food Processing Science, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Josh Warren
- 2 Institute for Food Safety and Health, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Lauren J Gonsalves
- 1 U.S. Food and Drug Administration, Division of Food Processing Science, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Tanvi Mhetras
- 2 Institute for Food Safety and Health, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Mary Lou Tortorello
- 1 U.S. Food and Drug Administration, Division of Food Processing Science, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
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19
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Combination Effect of High-Pressure Processing and Essential Oil (Melissa officinalis Extracts) or Their Constituents for the Inactivation of Escherichia coli in Ground Beef. FOOD BIOPROCESS TECH 2018. [DOI: 10.1007/s11947-018-2211-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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20
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Huang CY, Sheen S, Sommers C, Sheen LY. Modeling the Survival of Escherichia coli O157:H7 Under Hydrostatic Pressure, Process Temperature, Time and Allyl Isothiocyanate Stresses in Ground Chicken Meat. Front Microbiol 2018; 9:1871. [PMID: 30154776 PMCID: PMC6102346 DOI: 10.3389/fmicb.2018.01871] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 07/25/2018] [Indexed: 12/30/2022] Open
Abstract
Shiga toxin-producing Escherichia coli O157:H7 (STEC) is a common contaminant in meat and poultry. We investigated the use of non-thermal high pressure processing (HPP), with or without allyl isothiocyanate (AITC) essential oil, to kill STEC in ground chicken meat. Temperature was found an important factor affecting the inactivation of STEC in addition to pressure and process time. A full factorial experiment design (4 factors × 2 levels) was used to facilitate and evaluate the effect of pressure (250–350 MPa), operation temperature (−15–4°C), AITC concentration (0.05–0.15%, w/w), and pressure-holding time (10–20 min) on the inactivation of STEC. A linear model (a polynomial equation) was developed to predict/describe those four parameters’ impact on E. coli O157:H7 survival (R2 = 0.90), as well as a dimensionless non-linear model. Both types of models were validated with data obtained from separate experimental points. The dimensionless model also demonstrated that it may predict the lethality (defined as the log CFU/g reduction of STEC before and after treatment) reasonably well with some factors set slightly outside the design ranges (e.g., a wider application than the linear model). The results provide important information regarding STEC survival as affected by HPP (e.g., pressure, time and temperature) and AITC. With the addition of AITC, the hydrostatic pressure may be lowered to the 250–350 MPa level. Regulatory agencies and food industry may use those models for STEC risk assessment in ground chicken meat. A storage test (at 4 and 10°C, 10 days) after HPP+AITC treatment indicated that AITC may continue depressing or killing the pressure-damaged cells.
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Affiliation(s)
- Chi-Yun Huang
- Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan.,Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, PA, United States
| | - Shiowshuh Sheen
- Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, PA, United States
| | - Christopher Sommers
- Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, PA, United States
| | - Lee-Yan Sheen
- Institute of Food Science and Technology, National Taiwan University, Taipei, Taiwan
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21
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Woerner DR, Geornaras I, Martin JN, Belk KE, Acuff GR, Dickson JS. 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. J Food Prot 2018; 81:1068-1072. [PMID: 29893583 DOI: 10.4315/0362-028x.jfp-17-385] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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.
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Affiliation(s)
- Dale R Woerner
- 1 Center for Meat Safety and Quality, Department of Animal Sciences, Colorado State University, 1171 Campus Delivery, Fort Collins, Colorado 80523 (ORCID: http://orcid.org/0000-0002-0761-0720 [J.N.M.])
| | - Ifigenia Geornaras
- 1 Center for Meat Safety and Quality, Department of Animal Sciences, Colorado State University, 1171 Campus Delivery, Fort Collins, Colorado 80523 (ORCID: http://orcid.org/0000-0002-0761-0720 [J.N.M.])
| | - Jennifer N Martin
- 1 Center for Meat Safety and Quality, Department of Animal Sciences, Colorado State University, 1171 Campus Delivery, Fort Collins, Colorado 80523 (ORCID: http://orcid.org/0000-0002-0761-0720 [J.N.M.])
| | - Keith E Belk
- 1 Center for Meat Safety and Quality, Department of Animal Sciences, Colorado State University, 1171 Campus Delivery, Fort Collins, Colorado 80523 (ORCID: http://orcid.org/0000-0002-0761-0720 [J.N.M.])
| | - Gary R Acuff
- 2 Department of Nutrition and Food Science, 2253 TAMU, Texas A&M University, College Station, Texas 77843-2253; and
| | - James S Dickson
- 3 Department of Animal Science, 2372 Kildee, 806 Stange Road, Iowa State University, Ames, Iowa 50011, USA
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22
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Stratakos AC, Grant IR. Evaluation of the efficacy of multiple physical, biological and natural antimicrobial interventions for control of pathogenic Escherichia coli on beef. Food Microbiol 2018; 76:209-218. [PMID: 30166143 DOI: 10.1016/j.fm.2018.05.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 05/23/2018] [Accepted: 05/25/2018] [Indexed: 12/26/2022]
Abstract
Antimicrobial effects of multiple physical, biological and natural interventions on pathogenic Escherichia coli in raw beef were assessed. A cocktail of E. coli strains was inoculated onto gamma-irradiated beef and enumerated immediately after each intervention and during storage at 4 °C for 7 days. Of the physical interventions, silver-containing antimicrobial packaging and ozone gas treatment did not show significant antimicrobial effects, however cold plasma treatment reduced E. coli levels by 0.9 and 1.82 log10 CFU/cm2 after 2 and 5 min treatments, respectively. A phage cocktail reduced E. coli counts by 0.63 and 1.16 log10 CFU/g after 24 h storage at 4 and 12 °C, respectively. Of the natural interventions, vinegar and lactic acid (5%) washes for 5 min caused reductions of ∼1 log10 CFU/g immediately after treatment, whereas lactoferrin and nisin treatments, separately or in combination, had insignificant antimicrobial effects. Nanoemulsions containing carvacrol or thyme essential oils caused immediate E. coli reductions of 1.41 and 1.36 log10 CFU/g, respectively, plus a progressive reduction in viable numbers during storage at 4 °C. Our findings suggest that cold plasma, bacteriophages, vinegar, lactic acid, or carvacrol and thyme essential oil nanoemulsions could potentially be of use to the beef industry for controlling pathogenic E. coli contamination.
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Affiliation(s)
- Alexandros Ch Stratakos
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, UK
| | - Irene R Grant
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, UK.
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23
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Sheen S, Huang CY, Ramos R, Chien SY, Scullen OJ, Sommers C. Lethality Prediction for Escherichia Coli O157:H7 and Uropathogenic E. coli in Ground Chicken Treated with High Pressure Processing and Trans-Cinnamaldehyde. J Food Sci 2018; 83:740-749. [PMID: 29411883 DOI: 10.1111/1750-3841.14059] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 11/28/2017] [Accepted: 01/03/2018] [Indexed: 01/09/2023]
Abstract
UNLABELLED Pathogenic Escherichia coli, intestinal (O157:H7) as well as extraintestinal types (for example, Uropathogenic E. coli [UPEC]) are commonly found in many foods including raw chicken meat. The resistance of E. coli O157:H7 to UPEC in chicken meat under the stresses of high hydrostatic Pressure (HHP, also known as HPP-high pressure processing) and trans-cinnamaldehyde (an essential oil) was investigated and compared. UPEC was found slightly less resistant than O157:H7 in our test parameter ranges. With the addition of trans-cinnamaldehyde as an antimicrobial to meat, HPP lethality enhanced both O157:H7 and UPEC inactivation. To facilitate the predictive model development, a central composite design (CCD) was used to assess the 3-parameter effects, that is, pressure (300 to 400 MPa), trans-cinnamaldehyde dose (0.2 to 0.5%, w/w), and pressure-holding time (15 to 25 min), on the inactivation of E. coli O157:H7 and UPEC in ground chicken. Linear models were developed to estimate the lethality of E. coli O157:H7 (R2 = 0.86) and UPEC (R2 = 0.85), as well as dimensionless nonlinear models. All models were validated with data obtained from separated CCD combinations. Because linear models of O157:H7 and UPEC had similar R2 and the significant lethality difference of CCD points was only 9 in 20; all data were combined to generate models to include both O157:H7 and UPEC. The results provide useful information/tool to predict how pathogenic E. coli may survive HPP in the presence of trans-cinnamaldehyde and to achieve a great than 5 log CFU/g reduction in chicken meat. The models may be used for process optimization, product development and to assist the microbial risk assessment. PRACTICAL APPLICATION The study provided an effective means to reduce the high hydrostatic pressure level with incorporation of antimicrobial compound to achieve a 5-log reduction of pathogenic E. coli without damaging the raw meat quality. The developed models may be used to predict the high pressure processing lethality (and process optimization), product development (ingredient selection), and to assist the microbial risk assessment.
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Affiliation(s)
- Shiowshuh Sheen
- Eastern Regional Research Center, Agricultural Research Service, U.S. Dept. of Agriculture, Wyndmoor, PA 19038, U.S.A
| | - Chi-Yun Huang
- Eastern Regional Research Center, Agricultural Research Service, U.S. Dept. of Agriculture, Wyndmoor, PA 19038, U.S.A
- Inst. of Food Science and Technology, Natl. Taiwan Univ., Taiwan
| | - Rommel Ramos
- Eastern Regional Research Center, Agricultural Research Service, U.S. Dept. of Agriculture, Wyndmoor, PA 19038, U.S.A
| | - Shih-Yung Chien
- Inst. of Food Science and Technology, Natl. Taiwan Univ., Taiwan
| | - O Joseph Scullen
- Eastern Regional Research Center, Agricultural Research Service, U.S. Dept. of Agriculture, Wyndmoor, PA 19038, U.S.A
| | - Christopher Sommers
- Eastern Regional Research Center, Agricultural Research Service, U.S. Dept. of Agriculture, Wyndmoor, PA 19038, U.S.A
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24
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Effect of HPP treatment on the safety and quality of beef steak intended for sous vide cooking. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2017.07.037] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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25
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Liu Y, Yoo BB, Hwang CA, Suo Y, Sheen S, Khosravi P, Huang L. LMOf2365_0442 Encoding for a Fructose Specific PTS Permease IIA May Be Required for Virulence in L. monocytogenes Strain F2365. Front Microbiol 2017; 8:1611. [PMID: 28900418 PMCID: PMC5581801 DOI: 10.3389/fmicb.2017.01611] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/07/2017] [Indexed: 02/06/2023] Open
Abstract
Listeria monocytogenes is a foodborne pathogen that causes listeriosis, which is a major public health concern due to the high fatality rate. LMOf2365_0442, 0443, and 0444 encode for fructose-specific EIIABC components of phosphotransferase transport system (PTS) permease that is responsible for sugar transport. In previous studies, in-frame deletion mutants of a putative fructose-specific PTS permease (LMOf2365_0442, 0443, and 0444) were constructed and analyzed. However, the virulence potential of these deletion mutants has not been studied. In this study, two in vitro methods were used to analyze the virulence potential of these L. monocytogenes deletion mutants. First, invasion assays were used to measure the invasion efficiencies to host cells using the human HT-29 cell line. Second, plaque forming assays were used to measure cell-to-cell spread in host cells. Our results showed that the deletion mutant ΔLMOf2365_0442 had reduced invasion and cell-to-cell spread efficiencies in human cell line compared to the parental strain LMOf2365, indicating that LMOf2365_0442 encoding for a fructose specific PTS permease IIA may be required for virulence in L. monocytogenes strain F2365. In addition, the gene expression levels of 15 virulence and stress-related genes were analyzed in the stationary phase cells of the deletion mutants using RT-PCR assays. Virulence-related gene expression levels were elevated in the deletion mutants ΔLMOf2365_0442-0444 compared to the wild type parental strain LMOf2365, indicating the down-regulation of virulence genes by this PTS permease in L. monocytogenes. Finally, stress-related gene clpC expression levels were also increased in all of the deletion mutants, suggesting the involvement of this PTS permease in stress response. Furthermore, these deletion mutants displayed the same pressure tolerance and the same capacity for biofilm formation compared to the wild-type parental strain LMOf2365. In summary, our findings suggest that the LMOf2365_0442 gene can be used as a potential target to develop inhibitors for new therapeutic and pathogen control strategies for public health.
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Affiliation(s)
- Yanhong Liu
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Brian B Yoo
- Clinical and Environmental Microbiology Branch, Division of Healthcare Quality and Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, AtlantaGA, United States
| | - Cheng-An Hwang
- Residue Chemistry and Predictive Microbiology Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Yujuan Suo
- Institute for Agri-Food Standards and Testing Technology, Shanghai Academy of Agricultural SciencesShanghai, China
| | - Shiowshuh Sheen
- Food Safety Intervention Technologies Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Parvaneh Khosravi
- Food Safety Intervention Technologies Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
| | - Lihan Huang
- Residue Chemistry and Predictive Microbiology Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, WyndmoorPA, United States
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26
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Trevisani M, Valero A, Mancusi R. Effectiveness of the Thermal Treatments Used for Curd Stretching in the Inactivation of Shiga Toxin-Producing O157 and O26 Escherichia coli. BIOMED RESEARCH INTERNATIONAL 2017; 2017:1609836. [PMID: 28904945 PMCID: PMC5585639 DOI: 10.1155/2017/1609836] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 06/24/2017] [Accepted: 07/24/2017] [Indexed: 11/23/2022]
Abstract
The kneading treatment of the fresh curd in hot water is a critical control point in the manufacturing of mozzarella. Factors such as the ratio between hot water and curd mass, the rheological properties, and the mixing and kneading activity affect the processing time and the internal temperature of the curd. The aim of this study was to investigate the effect of thermal treatments on the fate of Shiga toxin-producing Escherichia coli (STEC). Nine curd samples (weight 160-270 g) were artificially contaminated with O157 or O26 STEC and stretched in hot water (90-95°C) for 5-10 min. Depending on the heating process and spinning, different nonisothermal profiles were recorded. Observed reductions of O157 and O26 STEC varied between 1.01 and more than 5.38 logMPN (Most Probable Number)/g at the end of the temperature treatments. Further, nonisothermal log-linear tail models were developed to compare observed reductions for O157 and O26 VTEC under variable temperature conditions. Results obtained showed that the comparison of predictions provided by the dynamic model with observations described well the linear inactivation pattern since nonsignificant differences were denoted at all profiles tested. The dynamic model developed can be useful to evaluate the effectiveness of the thermal treatments used in the manufacturing of mozzarella in the inactivation of STEC.
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Affiliation(s)
- M. Trevisani
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, Italy
| | - A. Valero
- Department of Food Science and Technology, University of Cordoba, International Campus of Excellence in the AgriFood Sector (ceiA3), Campus de Rabanales, Edificio Darwin, 14014 Córdoba, Spain
| | - R. Mancusi
- Department of Veterinary Medical Sciences, University of Bologna, Via Tolara di Sopra 50, 40064 Ozzano dell'Emilia, Italy
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27
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Balamurugan S, Ahmed R, Gao A, Strange P. Comparison of the fate of the top six non-O157 shiga-toxin producing Escherichia coli (STEC) and E. coli O157:H7 during the manufacture of dry fermented sausages. Int J Food Microbiol 2017; 259:14-21. [PMID: 28779623 DOI: 10.1016/j.ijfoodmicro.2017.07.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 07/20/2017] [Accepted: 07/26/2017] [Indexed: 12/20/2022]
Abstract
The study examined the relative fate of the top six non-O157 shiga-toxin producing Escherichia coli (STEC) and E. coli O157:H7 during the manufacture of dry fermented sausages (DFS). Three separate batches of sausages containing a five-strain cocktail for each serogroup and uninoculated control were manufactured and subjected to identical fermentation, maturation and dry curing conditions. Changes in physicochemical properties and inoculated STEC numbers were enumerated during the DFS production stages and log reduction and log reduction rates were calculated. Inoculation of very high concentrations (8logCFUg-1) of STEC in the sausage batter did not significantly (P>0.05) affect the changes in the pH, aw, moisture, protein, fat content compared to the uninoculated DFS. There was a significant (P<0.05) reduction in counts within the 48h fermentation for all STEC serogroups inoculated by about 0.97- to 1.42-log units. However, during the sausage maturation stage, all serogroups except O121 and O45 showed a significant reduction in numbers. During the extended 34day drying stage, all STEC serogroups showed a significant reduction in counts reaching a 5-log reduction within 20 to 27days of drying. ANOVA of the log reduction rates revealed significant differences in the reduction rates among the STEC serogroups examined. During the fermentation stage, serogroup O45 had the highest reduction rate at 0.98-logCFUg-1day-1 which was significantly higher compared to all other STEC serogroups (P<0.05), while O26 was the most tolerant to the conditions encountered during the fermentation stage with a reduction rate of 0.49-logCFUg-1day-1. However, during the extended 34days drying stage all STEC serogroups showed a steady reduction in population with a reduction rate ranging from 0.11- to 0.18-logCFUg-1day-1. The log reduction rate of E. coli O157:H7 was similar to that of serogroups O111 and O103, but was significantly lower (P<0.05) than all other STEC serogroups examined in the study. The log reduction rates of serogroups O121, O45, O145 and O26 during drying were not significantly different (P>0.05) from each other. These results indicate that the lethality of DFS production processes observed against E. coli O157:H7 would result in a similar inactivation of the top six non-O157 STEC.
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Affiliation(s)
- S Balamurugan
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, Ontario, Canada.
| | - Rafath Ahmed
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, Ontario, Canada
| | - Anli Gao
- Laboratory Services Division, University of Guelph, Guelph, Ontario, Canada
| | - Phil Strange
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, Ontario, Canada
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28
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Rodriguez-Souto RR, Garrido-Maestu A, Pastoriza-Fontan A, Lozano-Leon A. Investigation and characterization of Shiga toxin-producingEscherichia colipresent in mussels from harvesting areas in Galician southern Rias (NW Spain). J Food Saf 2017. [DOI: 10.1111/jfs.12367] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Alejandro Garrido-Maestu
- Department of Life Sciences, International Iberian Nanotechnology Laboratory, Nano4Food Unit; Food Quality and Safety Research Group, Av. Mestre José Veiga s/n 4715-330 Braga; Portugal
| | | | - Antonio Lozano-Leon
- Institute of Applied Microbiology - ASMECRUZ. Playa de Beluso s/n, Bueu PO 36939; Spain
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29
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Li X, Zeng WC, Zhu DY, Feng JL, Tian CC, Liao XP, Shi B. Investigation of collagen hydrolysate used as carbon and nitrogen source in the fermentation of Bacillus pumilus. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.01.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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30
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Modeling the inactivation of Escherichia coli O157:H7 and Uropathogenic E. coli in ground beef by high pressure processing and citral. Food Control 2017. [DOI: 10.1016/j.foodcont.2016.09.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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31
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Effects of High Hydrostatic Pressure Processing on the Number of Bacteria and Texture of Beef Liver. J FOOD QUALITY 2017. [DOI: 10.1155/2017/7835714] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Providing beef liver for raw consumption was banned in Japan on July 1, 2012. To lift the ban, the establishment of effective countermeasures for safe raw consumption is necessary. In this study, we examined the effects of high hydrostatic pressure processing on raw beef liver. Beef liver samples subjected to 300 MPa of pressure or higher for 10 min at 25°C became firmer and showed a paler color and were considered unsuitable for raw consumption. More than 3.0 log reductions of bacteria were seen after treatments at 400 and 500 MPa, but the treatment with lower pressure did not show enough microcidal effects for safe consumption. Histological and ultrastructural analysis revealed that high hydrostatic pressure processing increased mitochondrial swelling and reduced rough endoplasmic reticula in hepatocytes, and such changes might be related to the observed changes of texture in the treated raw beef liver.
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Differences in inactivation of Escherichia coli O157:H7 strains in ground beef following repeated high pressure processing treatments and cold storage. Food Microbiol 2016; 58:7-12. [DOI: 10.1016/j.fm.2016.02.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2015] [Accepted: 02/19/2016] [Indexed: 11/19/2022]
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Sheng L, Olsen S, Hu J, Yue W, Means W, Zhu M. Inhibitory effects of grape seed extract on growth, quorum sensing, and virulence factors of CDC “top-six” non-O157 Shiga toxin producing E. coli. Int J Food Microbiol 2016; 229:24-32. [DOI: 10.1016/j.ijfoodmicro.2016.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 03/15/2016] [Accepted: 04/01/2016] [Indexed: 10/22/2022]
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Chien SY, Sheen S, Sommers CH, Sheen LY. Modeling the Inactivation of Intestinal Pathogenic Escherichia coli O157:H7 and Uropathogenic E. coli in Ground Chicken by High Pressure Processing and Thymol. Front Microbiol 2016; 7:920. [PMID: 27379050 PMCID: PMC4906548 DOI: 10.3389/fmicb.2016.00920] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/30/2016] [Indexed: 12/30/2022] Open
Abstract
Disease causing Escherichia coli commonly found in meat and poultry include intestinal pathogenic E. coli (iPEC) as well as extraintestinal types such as the Uropathogenic E. coli (UPEC). In this study we compared the resistance of iPEC (O157:H7) to UPEC in chicken meat using High Pressure Processing (HPP) in with (the hurdle concept) and without thymol essential oil as a sensitizer. UPEC was found slightly more resistant than E. coli O157:H7 (iPEC O157:H7) at 450 and 500 MPa. A central composite experimental design was used to evaluate the effect of pressure (300–400 MPa), thymol concentration (100–200 ppm), and pressure-holding time (10–20 min) on the inactivation of iPEC O157:H7 and UPEC in ground chicken. The hurdle approach reduced the high pressure levels and thymol doses imposed on the food matrices and potentially decreased food quality damaged after treatment. The quadratic equations were developed to predict the impact (lethality) on iPEC O157:H7 (R2 = 0.94) and UPEC (R2 = 0.98), as well as dimensionless non-linear models [Pr > F (<0.0001)]. Both linear and non-linear models were validated with data obtained from separated experiment points. All models may predict the inactivation/lethality within the same order of accuracy. However, the dimensionless non-linear models showed potential applications with parameters outside the central composite design ranges. The results provide useful information of both iPEC O157:H7 and UPEC in regard to how they may survive HPP in the presence or absence of thymol. The models may further assist regulatory agencies and food industry to assess the potential risk of iPEC O157:H7 and UPEC in ground chicken.
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Affiliation(s)
- Shih-Yung Chien
- Institute of Food Science and Technology, National Taiwan UniversityTaipei, Taiwan; United States Department of Agriculture, Eastern Regional Research Center, Agricultural Research ServiceWyndmoor, PA USA
| | - Shiowshuh Sheen
- United States Department of Agriculture, Eastern Regional Research Center, Agricultural Research Service Wyndmoor, PA USA
| | - Christopher H Sommers
- United States Department of Agriculture, Eastern Regional Research Center, Agricultural Research Service Wyndmoor, PA USA
| | - Lee-Yan Sheen
- Institute of Food Science and Technology, National Taiwan University Taipei, Taiwan
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IRSHAD H, COOKSON AL, ROSS CM, JAROS P, PRATTLEY DJ, DONNISON A, McBRIDE G, MARSHALL J, FRENCH NP. Diversity and relatedness of Shiga toxin-producing Escherichia coli and Campylobacter jejuni between farms in a dairy catchment. Epidemiol Infect 2016; 144:1406-17. [PMID: 26593403 PMCID: PMC9150598 DOI: 10.1017/s0950268815002782] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 09/24/2015] [Accepted: 10/23/2015] [Indexed: 11/07/2022] Open
Abstract
The aim of this study was to examine the population structure, transmission and spatial relationship between genotypes of Shiga toxin-producing Escherichia coli (STEC) and Campylobacter jejuni, on 20 dairy farms in a defined catchment. Pooled faecal samples (n = 72) obtained from 288 calves were analysed by real-time polymerase chain reaction (rtPCR) for E. coli serotypes O26, O103, O111, O145 and O157. The number of samples positive for E. coli O26 (30/72) was high compared to E. coli O103 (7/72), O145 (3/72), O157 (2/72) and O111 (0/72). Eighteen E. coli O26 and 53 C. jejuni isolates were recovered from samples by bacterial culture. E. coli O26 and C. jejuni isolates were genotyped using pulsed-field gel electrophoresis and multilocus sequence typing, respectively. All E. coli O26 isolates could be divided into four clusters and the results indicated that E. coli O26 isolates recovered from calves on the same farm were more similar than isolates recovered from different farms in the catchment. There were 11 different sequence types of C. jejuni isolated from the cattle and 22 from water. An analysis of the population structure of C. jejuni isolated from cattle provided evidence of clustering of genotypes within farms, and among groups of farms separated by road boundaries.
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Affiliation(s)
- H. IRSHAD
- mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
- Animal Health Programme, Animal Sciences Institute, National Agricultural Research Centre, Park Road, Islamabad, Pakistan
| | - A. L. COOKSON
- mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
- AgResearch Ltd, Hopkirk Research Institute, Palmerston North, New Zealand
| | - C. M. ROSS
- AgResearch Ltd, Ruakura Research Centre, Hamilton, New Zealand
| | - P. JAROS
- mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
| | - D. J. PRATTLEY
- mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
| | - A. DONNISON
- AgResearch Ltd, Ruakura Research Centre, Hamilton, New Zealand
| | - G. McBRIDE
- National Institute of Water and Atmospheric Research (NIWA), Hamilton, New Zealand
| | - J. MARSHALL
- mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
| | - N. P. FRENCH
- mEpiLab, Infectious Disease Research Centre, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
- Allan Wilson Centre for Molecular Ecology and Evolution, Massey University, Palmerston North, New Zealand
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36
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Sheen S, Cassidy J, Scullen B, Sommers C. Inactivation of a diverse set of shiga toxin-producing Escherichia coli in ground beef by high pressure processing. Food Microbiol 2015; 52:84-7. [DOI: 10.1016/j.fm.2015.07.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 06/25/2015] [Accepted: 07/02/2015] [Indexed: 11/29/2022]
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37
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38
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Gänzle M, Liu Y. Mechanisms of pressure-mediated cell death and injury in Escherichia coli: from fundamentals to food applications. Front Microbiol 2015; 6:599. [PMID: 26157424 PMCID: PMC4478891 DOI: 10.3389/fmicb.2015.00599] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 06/01/2015] [Indexed: 12/12/2022] Open
Abstract
High hydrostatic pressure is commercially applied to extend the shelf life of foods, and to improve food safety. Current applications operate at ambient temperature and 600 MPa or less. However, bacteria that may resist this pressure level include the pathogens Staphylococcus aureus and strains of Escherichia coli, including shiga-toxin producing E. coli. The resistance of E. coli to pressure is variable between strains and highly dependent on the food matrix. The targeted design of processes for the safe elimination of E. coli thus necessitates deeper insights into mechanisms of interaction and matrix-strain interactions. Cellular targets of high pressure treatment in E. coli include the barrier properties of the outer membrane, the integrity of the cytoplasmic membrane as well as the activity of membrane-bound enzymes, and the integrity of ribosomes. The pressure-induced denaturation of membrane bound enzymes results in generation of reactive oxygen species and subsequent cell death caused by oxidative stress. Remarkably, pressure resistance at the single cell level relates to the disposition of misfolded proteins in inclusion bodies. While the pressure resistance E. coli can be manipulated by over-expression or deletion of (stress) proteins, the mechanisms of pressure resistance in wild type strains is multi-factorial and not fully understood. This review aims to provide an overview on mechanisms of pressure-mediated cell death in E. coli, and the use of this information for optimization of high pressure processing of foods.
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Affiliation(s)
- Michael Gänzle
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
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Garcia-Hernandez R, McMullen L, Gänzle MG. Development and validation of a surrogate strain cocktail to evaluate bactericidal effects of pressure on verotoxigenic Escherichia coli. Int J Food Microbiol 2015; 205:16-22. [PMID: 25866907 DOI: 10.1016/j.ijfoodmicro.2015.03.028] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 03/19/2015] [Accepted: 03/24/2015] [Indexed: 12/21/2022]
Abstract
Many strains of verotoxigenic Escherichia coli (VTEC) are highly resistant to pressure. To facilitate future studies to improve the elimination of VTEC by pressure processing of food, this study developed and validated a cocktail of non-pathogenic strains of E. coli with equal or higher resistance to pressure when compared to pressure resistant strains of VTEC. Strains of E. coli obtained from a beef processing plant were screened for their resistance to heat and pressure. Treatments were carried out in LB broth. Cell counts of 3 out of 16 strains were reduced by 5-6 log (cfu/mL) after 30 min at 60 °C, and cell counts of 10 out of 16 strains were reduced by 5-6 log (cfu/mL) after 30 min at 40 °C and 400 MPa. All highly heat resistant strains were also pressure resistant but not all pressure resistant strains were also heat resistant. Pressure resistant and -sensitive strains of E. coli were treated in presence of 0 or 2% NaCl and at 3, 20, or 40 °C. The effect of these parameters on the lethality of pressure treatments was comparable for all strains. The addition of 2% NaCl did not increase pressure resistance. The bactericidal effect of treatments at 3 and 20 °C and 600 MPa was comparable but inactivation of E. coli was faster at 40 °C and 600 MPa. The resistance to treatment with 600 MPa at 20 °C of a cocktail of 5 non-pathogenic strains of E. coli was compared to a 5 strain cocktail of pressure resistant VTEC. Treatments were performed in ground beef containing 15% fat. Survival and sublethal injury of the two cocktails was comparable; cell counts of beef inoculated with either cocktail were reduced by about 4 log (cfu/mL) after 30 min of treatment. In conclusion, this study validated a cocktail of non-pathogenic strains of E. coli for use as surrogate organisms in studies on the elimination of E. coli by pressure.
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Affiliation(s)
| | - Lynn McMullen
- University of Alberta, Department of Agricultural, Food and Nutritional Science, Edmonton, Canada
| | - Michael G Gänzle
- University of Alberta, Department of Agricultural, Food and Nutritional Science, Edmonton, Canada.
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40
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Zhang Y, Dai B, Deng Y, Zhao Y. AFM and NMR imaging of squid tropomyosin Tod p1 subjected to high hydrostatic pressure: evidence for relationships among topography, characteristic domain and allergenicity. RSC Adv 2015. [DOI: 10.1039/c5ra13655e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The surface topography, characteristic domain and allergenicity of squid tropomyosin Tod p1 (TMTp1) treated under single- and two-cycle high hydrostatic pressure (HHP) were analyzed.
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Affiliation(s)
- Yifeng Zhang
- Key Laboratory of Urban Agriculture (South)
- Ministry of Agriculture
- SJTU-Bor S. Luh Food Safety Center
- Department of Food Science and Technology
- Shanghai Jiao Tong University
| | - Bona Dai
- Instrumental Analysis Center
- Shanghai Jiao Tong University
- 200240 Shanghai
- China
| | - Yun Deng
- Key Laboratory of Urban Agriculture (South)
- Ministry of Agriculture
- SJTU-Bor S. Luh Food Safety Center
- Department of Food Science and Technology
- Shanghai Jiao Tong University
| | - Yanyun Zhao
- Department of Food Science & Technology
- Oregon State University
- Corvallis
- USA
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