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Öztürk F, Gündüz H, Sürengil G. The effects of essential oils on inactivation of
Listeria monocytogenes
in rainbow trout cooked with sous‐vide. J FOOD PROCESS PRES 2021. [DOI: 10.1111/jfpp.15878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Fatma Öztürk
- Department of Fisheries and Fish Processing Technology Faculty of Fisheries Izmir Katip Celebi University Izmir Turkey
| | - Hatice Gündüz
- Department of Fisheries and Fish Processing Technology Faculty of Fisheries Izmir Katip Celebi University Izmir Turkey
| | - Göknur Sürengil
- Department of Fisheries and Fish Processing Technology Faculty of Fisheries Izmir Katip Celebi University Izmir Turkey
- Department of Fishing and Processing Technology Faculty of Eğirdir Fisheries University of Isparta Applied Sciences Isparta Turkey
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2
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Hansen TB, Abdalas S, Al-Hilali I, Hansen LT. Predicting the effect of salt on heat tolerance of Listeria monocytogenes in meat and fish products. Int J Food Microbiol 2021; 352:109265. [PMID: 34116257 DOI: 10.1016/j.ijfoodmicro.2021.109265] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 01/22/2021] [Accepted: 05/23/2021] [Indexed: 10/21/2022]
Abstract
Listeria monocytogenes is a potentially fatal foodborne pathogen that can be found in various ready-to-eat (RTE) products. It tolerates adverse conditions such as high salt concentrations and refrigerated storage, thus, the elimination of the pathogen in food processing often relies on heat processing. The objective of this study was to create a model to predict the effect of salt on heat tolerance of L. monocytogenes in meat and seafood products during heat treatments conducted at 57 to 65 °C to reduce numbers by ≥3 log10 cycles. Salt concentrations, up to 6% in the water phase (WPS%), were applied to cover a variety of lightly salted RTE meat and seafood products. The experimental work involved samples of ground pork tenderloin, ground chicken breast fillet and skinned, ground salmon fillet adjusted to different WPS% i.e., 3.6 and 5.2 WPS% for pork samples, 2.0, 3.0, 3.5 and 6.0 WPS% for chicken samples and 3.0 and 6.0 WPS% for salmon samples. All samples were inoculated with late-stationary phase L. monocytogenes cultures. For pork samples, a two-strain mixture of a pork isolate (MS22254) and an environmental isolate (MS22246) was applied. For chicken and salmon samples, a seafood isolate (MS22258) and isolate MS22246 was applied as single cultures. Samples were vacuum-packed in sterile bags, immerged in water bath, and held at constant temperatures of 57, 60 and 65 °C for pork samples and 58, 61 and 62.5 °C for chicken and salmon samples. For survivor curves, where at least 3 log10-reduction were obtained, heat tolerance was expressed as decimal reduction times, D-values. D-values were observed to increase with increasing WPS%. The effect of salt on heat tolerance of L. monocytogenes was defined as the relative increase (RI-value) in D-value obtained when salt had been added to the food. The effect of WPS% on RI-values was independent of heating temperatures, foods and strains. For secondary modelling, RI-values were transformed using the natural logarithm, ln(RI) and fitted to a linear model as a function of WPS%. Model validation, with 56 independent values collected from the scientific literature, resulted in bias and accuracy factors of 0.89 and 1.26, respectively, suggesting acceptable performance with tendency to slightly under-predict. The developed predictive model can be used to guide the design of heat processes for manufacturers of lightly preserved and mildly processed meat and seafood products requiring more than 3 log10 reduction of L. monocytogenes to ensure safety.
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Affiliation(s)
- Tina Beck Hansen
- The National Food Institute, Technical University of Denmark, Division for Microbiology and Production, Kemitorvet, Building 202, DK-2800 Kgs. Lyngby, Denmark.
| | - Somaya Abdalas
- The National Food Institute, Technical University of Denmark, Division for Microbiology and Production, Kemitorvet, Building 202, DK-2800 Kgs. Lyngby, Denmark
| | - Iman Al-Hilali
- The National Food Institute, Technical University of Denmark, Division for Microbiology and Production, Kemitorvet, Building 202, DK-2800 Kgs. Lyngby, Denmark
| | - Lisbeth Truelstrup Hansen
- The National Food Institute, Technical University of Denmark, Division for Microbiology and Production, Kemitorvet, Building 202, DK-2800 Kgs. Lyngby, Denmark
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3
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Dogruyol H, Mol S, Cosansu S. Increased thermal sensitivity of Listeria monocytogenes in sous-vide salmon by oregano essential oil and citric acid. Food Microbiol 2020; 90:103496. [PMID: 32336368 DOI: 10.1016/j.fm.2020.103496] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 01/13/2020] [Accepted: 03/17/2020] [Indexed: 11/19/2022]
Abstract
Inadequate cooking during sous-vide processing may cause foodborne diseases in case the food is contaminated with pathogens such as Listeria monocytogenes. In this study, thermal inactivation of L. monocytogenes in sous-vide processed salmon was investigated. Oregano oil and citric acid were used alone or in combination to determine the probability of increasing the efficiency of heat treatment. Control (C); 0.5% citric acid added (S); 1% oregano essential oil added (O); and citric acid and oregano essential oil combined (OS) groups were prepared. Samples were inoculated with L. monocytogenes, vacuum packed, then sous-vide cooked at 55, 57.5, 60, or 62.5 °C for predetermined times. The D-values of all treated samples were significantly lower than control. The use of oregano oil (O), citric acid (S) and their combination (OS) significantly reduced the time required to inactivate L. monocytogenes. The z-values of L. monocytogenes in C, O, S and OS groups were 5.50, 5.62, 6.54, and 6.92 °C, respectively. It was determined that effective results could be achieved by adding natural antimicrobials to provide safety in sous-vide fish.
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Affiliation(s)
- Hande Dogruyol
- Istanbul University, Faculty of Aquatic Sciences, Department of Seafood Processing Technology, Ordu Cad. No.8, 34134, Istanbul, Turkey.
| | - Suhendan Mol
- Istanbul University, Faculty of Aquatic Sciences, Department of Seafood Processing Technology, Ordu Cad. No.8, 34134, Istanbul, Turkey
| | - Serap Cosansu
- Sakarya University, Faculty of Engineering, Department of Food Engineering, 54187, Esentepe, Sakarya, Turkey
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Abel N, Rotabakk BT, Lerfall J. Effect of heat treatment and packaging technology on the microbial load of lightly processed seafood. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2018.11.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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5
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McDermott A, Whyte P, Brunton N, Bolton DJ. Thermal Inactivation of Listeria monocytogenes in Crab Meat. J Food Prot 2018; 81:2003-2006. [PMID: 30476441 DOI: 10.4315/0362-028x.jfp-18-276] [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
Listeria monocytogenes is an important bacterial pathogen in seafood products, but limited information is currently available on the thermal resistance of relevant isolates in seafood. Thermal inactivation studies were undertaken (i) to provide much needed thermal inactivation data for L. monocytogenes in crab meat and (ii) to investigate whether tryptone soya broth (TSB) is representative of crab meat in thermal inactivation studies involving L. monocytogenes. D-values were obtained for a cocktail of two crab isolates (serotypes 1/2a and 4b) at 50, 55, and 60°C. In crab meat, D-values were 174.4, 28.2, and 1.6 min, respectively. Similar D-values of 176.4, 28.8, and 1.4 min were obtained in TSB. The corresponding z-values were 4.9°C (crab meat) and 4.8°C (TSB), respectively. The conclusions were that (i) current pasteurization conditions (e.g., 70°C for 2 min) would achieve complete destruction of any L. monocytogenes present in crab meat and (ii) TSB could be used as a model matrix for assessing the thermal inactivation of L. monocytogenes in crab meat.
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Affiliation(s)
- A McDermott
- 1 Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland.,2 School of Veterinary Medicine
| | - P Whyte
- 2 School of Veterinary Medicine
| | - N Brunton
- 3 School of Agriculture and Food Science, University College Dublin, Belfield, Dublin 4, Ireland
| | - D J Bolton
- 1 Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland
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6
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Comparison of oxidative stress response and biofilm formation of Listeria monocytogenes serotypes 4b and 1/2a. Food Control 2018. [DOI: 10.1016/j.foodcont.2017.10.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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7
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Ramroop P, Neetoo H. Antilisterial activity of Cymbopogon citratus on crabsticks. AIMS Microbiol 2018; 4:67-84. [PMID: 31294204 PMCID: PMC6605026 DOI: 10.3934/microbiol.2018.1.67] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 01/16/2018] [Indexed: 12/03/2022] Open
Abstract
Listeria monocytogenes is a gram positive, psychrotrophic, facultative anaerobic bacterium and it is the etiological agent of listeriosis, a severe foodborne disease of major public health concern. There is a rising concern about the cross-contamination of surimi-based products with L. monocytogenes during handling and storage. Lemon grass (Cymbopogon citratus) is known to exhibit strong antimicrobial activity against bacteria due to the presence of citral. The objectives of this research were: (i) to develop a water-based extraction procedure for the antimicrobial component(s) in lemon grass and (ii) to evaluate the antimicrobial effect of a concentrated water-based extract and commercial essential oil (EO) of lemon grass against L. innocua (ATCC 33090), a surrogate strain of L. monocytogenes, in vitro and on crabsticks. Briefly, antilisterial activity of concentrated extract and commercial EO of lemon grass was tested using the agar well diffusion technique. Crabsticks were subsequently inoculated with L. innocua to a final density of ca. 4 log cfu/g and then coated with 500 μl of either concentrated extract or 0.5% commercial EO and stored at 4 °C for up to 15 days. Samples were then subjected to microbiological analysis every 5 days to enumerate counts of Listeria. Following the agar well diffusion assay, inhibition zones with mean diameters of 18.3 and 21.0 mm were obtained with the concentrated extract and commercial EO respectively. The population of L. innocua in WBE-coated (4.2 log cfu/g) and 0.5% EO-coated (2.7 log cfu/g) samples were significantly lower (P < 0.05) after 15 days than their untreated control counterpart (5.2 log cfu/g). Lemon grass extract and essential oil have the potential to control growth of L. monocytogenes in seafood surimi products with minimal adverse effect on the organoleptic characteristics of the product and thus can possibly be used as a natural food preservative.
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Affiliation(s)
- Prateebha Ramroop
- Department of Agricultural and Food Sciences, Faculty of Agriculture, University of Mauritius, Mauritius
| | - Hudaa Neetoo
- Department of Agricultural and Food Sciences, Faculty of Agriculture, University of Mauritius, Mauritius
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8
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Antibacterial effect of 460 nm light-emitting diode in combination with riboflavin against Listeria monocytogenes on smoked salmon. Food Control 2018. [DOI: 10.1016/j.foodcont.2017.08.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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9
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Lekjing S, Karrila S, Siripongvutikorn S. Thermal Inactivation of Listeria monocytogenes in Whole Oysters (Crassostrea belcheri) and Pasteurization Effects on Meat Quality. JOURNAL OF AQUATIC FOOD PRODUCT TECHNOLOGY 2017. [DOI: 10.1080/10498850.2017.1376237] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Somwang Lekjing
- Faculty of Science and Industrial Technology, Prince of Songkla University, Surat Thani, Thailand
| | - Seppo Karrila
- Faculty of Science and Industrial Technology, Prince of Songkla University, Surat Thani, Thailand
| | - Sunisa Siripongvutikorn
- Department of Food Technology, Faculty of Agro-Industry, Prince of Songkla University, Hat Yai, Songkhla, Thailand
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Knudsen GM, Nielsen JB, Marvig RL, Ng Y, Worning P, Westh H, Gram L. Genome-wide-analyses of Listeria monocytogenes from food-processing plants reveal clonal diversity and date the emergence of persisting sequence types. ENVIRONMENTAL MICROBIOLOGY REPORTS 2017; 9:428-440. [PMID: 28574206 DOI: 10.1111/1758-2229.12552] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 05/27/2017] [Indexed: 06/07/2023]
Abstract
Whole genome sequencing is increasing used in epidemiology, e.g. for tracing outbreaks of food-borne diseases. This requires in-depth understanding of pathogen emergence, persistence and genomic diversity along the food production chain including in food processing plants. We sequenced the genomes of 80 isolates of Listeria monocytogenes sampled from Danish food processing plants over a time-period of 20 years, and analysed the sequences together with 10 public available reference genomes to advance our understanding of interplant and intraplant genomic diversity of L. monocytogenes. Except for three persisting sequence types (ST) based on Multi Locus Sequence Typing being ST7, ST8 and ST121, long-term persistence of clonal groups was limited, and new clones were introduced continuously, potentially from raw materials. No particular gene could be linked to the persistence phenotype. Using time-based phylogenetic analyses of the persistent STs, we estimate the L. monocytogenes evolutionary rate to be 0.18-0.35 single nucleotide polymorphisms/year, suggesting that the persistent STs emerged approximately 100 years ago, which correlates with the onset of industrialization and globalization of the food market.
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Affiliation(s)
- Gitte M Knudsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Jesper Boye Nielsen
- Department of Clinical Microbiology, Hvidovre Hospital, MRSA KnowledgeCenter, Hvidovre, Denmark
| | - Rasmus L Marvig
- Center for Genomic Medicine, Rigshospitalet, Copenhagen, Denmark
| | - Yin Ng
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Peder Worning
- Department of Clinical Microbiology, Hvidovre Hospital, MRSA KnowledgeCenter, Hvidovre, Denmark
| | - Henrik Westh
- Department of Clinical Microbiology, Hvidovre Hospital, MRSA KnowledgeCenter, Hvidovre, Denmark
- Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Lone Gram
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Kongens Lyngby, Denmark
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12
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Wood MV, Sreedharan A, Silverberg R, Balaguero AN, Schneider KR. The Effects of Heat Shock on the D-Values of <i>Listeria monocytogenes</i> on Selected Seafood Matrices. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/aim.2015.58060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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13
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Berrang ME, Hofacre CL, Frank JF. Controlling attachment and growth of Listeria monocytogenes in polyvinyl chloride model floor drains using a peroxide chemical, chitosan-arginine, or heat. J Food Prot 2014; 77:2129-32. [PMID: 25474061 DOI: 10.4315/0362-028x.jfp-14-300] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Listeria monocytogenes can colonize a poultry processing plant as a resident in floor drains. Limiting growth and attachment to drain surfaces may help lessen the potential for cross-contamination of product. The objective of this study was to compare a hydrogen peroxide-peroxyacetic acid-based chemical to chitosan-arginine or heat to prevent attachment of or destroy existing L. monocytogenes on the inner surface of model floor drains. L. monocytogenes was introduced to result in about 10(9) planktonic and attached cells within untreated polyvinyl chloride model drain pipes. Treatments (0.13 % peroxide-based sanitizer, 0.1 % chitosan-arginine, or 15 s of hot water at 95 to 100°C) were applied immediately after inoculation or after 24 h of incubation. Following treatment, all pipes were incubated for an additional 24 h; planktonic and attached cells were enumerated by plate count. All treatments significantly (P < 0.05) lowered numbers of planktonic and attached cells recovered. Chitosan-arginine resulted in approximately a 6-log reduction in planktonic cells when applied prior to incubation and a 3-log reduction after the inoculum had a chance to grow. Both heat and peroxide significantly outperformed chitosan-arginine (8- to 9-log reduction) and were equally effective before and after incubation. Heat was the only treatment that eliminated planktonic L. monocytogenes. All treatments were less effective against attached cells. Chitosan-arginine provided about a 4.5-log decrease in attached cells when applied before incubation and no significant decrease when applied after growth. Like with planktonic cells, peroxide-peroxyacetic acid and heat were equally effective before or after incubation, causing decreases ranging from 7 to 8.5 log for attached L. monocytogenes. Applied at the most efficacious time, any of these techniques may lessen the potential for L. monocytogenes to remain as a long-term resident in processing plant floor drains.
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Affiliation(s)
- Mark E Berrang
- U.S. Department of Agriculture, Agricultural Research Service, Russell Research Center, Athens, Georgia 30605, USA.
| | - Charles L Hofacre
- Department of Population Health, University of Georgia, Athens, Georgia 30605, USA
| | - Joseph F Frank
- Department of Food Science and Technology, University of Georgia, Athens, Georgia 30602, USA
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Delgado Suárez EJ, Chairéz Espinosa A, Sierra Gómez pedroso LDC, Rodas Suárez O, Quiñones Ramírez EI, Rubio Lozano MS. Hot Water Shrinkage as a Post-Lethal Intervention against L
isteria Monocytogenes
: Preliminary Assessment in a Turkey-Based Virginia Ham Model. J Food Saf 2014. [DOI: 10.1111/jfs.12168] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Enrique Jesús Delgado Suárez
- Facultad de Medicina Veterinaria y Zootecnia; Universidad Nacional Autónoma de México; Ciudad Universitaria 04510 México DF México
| | - Aldebarán Chairéz Espinosa
- Facultad de Medicina Veterinaria y Zootecnia; Universidad Nacional Autónoma de México; Ciudad Universitaria 04510 México DF México
| | | | - Oscar Rodas Suárez
- Escuela Nacional de Ciencias Biológicas; Instituto Politécnico Nacional; México D. F. México
| | | | - María Salud Rubio Lozano
- Facultad de Medicina Veterinaria y Zootecnia; Universidad Nacional Autónoma de México; Ciudad Universitaria 04510 México DF México
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Shi Y, Tang J, Yue T, Rasco B, Wang S. Pasteurizing Cold Smoked Salmon (Oncorhynchus nerka): Thermal Inactivation Kinetics ofListeria monocytogenesandListeria innocua. JOURNAL OF AQUATIC FOOD PRODUCT TECHNOLOGY 2014. [DOI: 10.1080/10498850.2013.808303] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Tocmo R, Krizman K, Khoo WJ, Phua LK, Kim M, Yuk HG. Listeria monocytogenes in Vacuum-Packed Smoked Fish Products: Occurrence, Routes of Contamination, and Potential Intervention Measures. Compr Rev Food Sci Food Saf 2014; 13:172-189. [PMID: 33412645 DOI: 10.1111/1541-4337.12052] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 11/14/2003] [Indexed: 12/15/2022]
Abstract
The occurrence of Listeria monocytogenes in ready-to-eat (RTE) fish products is well documented and represents an important food safety concern. Contamination of this pathogen in vacuum-packed (VP) smoked fish products at levels greater than the RTE food limit (100 CFU/g) has been traced to factors such as poor sanitary practices, contaminated processing environments, and temperature abuse during prolonged storage in retail outlets. Intervention technologies including physical, biological, and chemical techniques have been studied to control transmission of L. monocytogenes to these products. High-pressure processing, irradiation, and pulsed UV-light treatment have shown promising results. Potential antilisterial effects of some sanitizers and combined chemical preservatives have also been demonstrated. Moreover, the concept of biopreservation, use of bioactive packaging, and a combination of different intervention technologies, as in the hurdle concept, are also under consideration. In this review, the prevalence, routes of contamination, and potential intervention technologies to control transmission of L. monocytogenes in VP smoked fish products are discussed.
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Affiliation(s)
- Restituto Tocmo
- Food Science & Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, 3 Science Drive 3, Singapore, 117543
| | - Katja Krizman
- Food Science & Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, 3 Science Drive 3, Singapore, 117543
| | - Wei Jie Khoo
- Food Science & Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, 3 Science Drive 3, Singapore, 117543
| | - Li Kai Phua
- Food Science & Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, 3 Science Drive 3, Singapore, 117543
| | - Minjeong Kim
- Food Science & Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, 3 Science Drive 3, Singapore, 117543
| | - Hyun-Gyun Yuk
- Food Science & Technology Programme, Dept. of Chemistry, Natl. Univ. of Singapore, 3 Science Drive 3, Singapore, 117543
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Lianou A, Koutsoumanis KP. Strain variability of the behavior of foodborne bacterial pathogens: A review. Int J Food Microbiol 2013; 167:310-21. [DOI: 10.1016/j.ijfoodmicro.2013.09.016] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 09/23/2013] [Accepted: 09/24/2013] [Indexed: 10/26/2022]
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Klanicova B, Lorencova A, Makovcova J, Vlkova H, Kralik P, Pavlik I, Slany M. Survival of three Mycobacterium aviumsubsp. hominissuisisolates in fish products after hot smoking and frying. Int J Food Sci Technol 2013. [DOI: 10.1111/j.1365-2621.2012.03215.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Barbora Klanicova
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
| | - Alena Lorencova
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
| | - Jitka Makovcova
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
| | - Hana Vlkova
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
| | - Petr Kralik
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
| | - Ivo Pavlik
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
| | - Michal Slany
- Veterinary Research Institute; Hudcova 70; 621 00; Brno; Czech Republic
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AGUILAR C, VALENCIA V, OCHOA O, KLOTZ B. IMPROVING FOOD THERMAL PROCESSING: A DEATH-TIME STUDY ON PROCESSED MEAT PRODUCTS. J FOOD PROCESS PRES 2012. [DOI: 10.1111/j.1745-4549.2011.00627.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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MOL SUHENDAN, OZTURAN SAMIME, COSANSU SERAP. DETERMINATION OF THE QUALITY AND SHELF LIFE OF SOUS VIDE PACKAGED WHITING (MERLANGIUS MERLANGUS EUXINUS, NORDMAN, 1840) STORED AT COLD (4C) AND TEMPERATURE ABUSE (12C). J FOOD PROCESS PRES 2012. [DOI: 10.1111/j.1745-4549.2011.00616.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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21
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MOL SUHENDAN, OZTURAN SAMIME, COSANSU SERAP. DETERMINATION OF THE QUALITY AND SHELF LIFE OF SOUS VIDE PACKAGED BONITO (SARDA SARDA, BLOCH, 1793) STORED AT 4 AND 12C. J FOOD QUALITY 2012. [DOI: 10.1111/j.1745-4557.2011.00430.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Skåra T, Cappuyns AM, Johnsen SO, Van Derlinden E, Rosnes JT, Olsen Ø, Impe JFMV, Valdramidis VP. A thermodynamic approach to assess a cellular mechanism of inactivation and the thermal resistance of Listeria innocua. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.profoo.2011.09.146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Muñoz M, Guevara L, Palop A, Fernández PS. Prediction of time to growth of Listeria monocytogenes using Monte Carlo simulation or regression analysis, influenced by sublethal heat and recovery conditions. Food Microbiol 2010; 27:468-75. [DOI: 10.1016/j.fm.2009.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Revised: 11/06/2009] [Accepted: 12/11/2009] [Indexed: 11/26/2022]
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25
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Jiang L, Olesen I, Andersen T, Fang W, Jespersen L. Survival of Listeria monocytogenes in simulated gastrointestinal system and transcriptional profiling of stress- and adhesion-related genes. Foodborne Pathog Dis 2010; 7:267-74. [PMID: 19899961 DOI: 10.1089/fpd.2009.0361] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Food ingestion is the major route of exposure to the important human pathogen Listeria monocytogenes. An in vitro gastrointestinal model was used to (1) compare the survival rates of L. monocytogenes strains of serotypes 1/2a, 1/2c, and 4b; and (2) examine the transcription of stress- and adhesion-related genes after exposure to the conditions similar to those encountered in the mouth, stomach, and small intestine. None of the L. monocytogenes strains investigated could survive in the gastric juice at pH 2.5 or 3.0. Their survival increased at higher pH (3.5 and 4.0) in the gastric stress. Relative survival of L. monocytogenes serotypes 4b and 1/2a strains were higher than that of serotype 1/2c, suggesting that pathogenicity might be related to the viability in the gastrointestinal tract. The transcription levels of prfA and the general stress-related genes clpC, clpE, and clpP were upregulated after passing through the simulated gastrointestinal tract, whereas that of the adhesion-related gene ami was downregulated. Taken together, this study revealed that L. monocytogenes strains enhanced the expression of stress-related genes and decreased the transcription of adhesion-related gene in order to survive in the diverse microenvironments.
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Affiliation(s)
- Lingli Jiang
- Zhejiang University Institute of Preventive Veterinary Medicine, and Zhejiang Provincial Key Laboratory for Preventive Veterinary Medicine, Hangzhou, Zhejiang, People's Republic of China
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Skipnes D, Johnsen SO, Skåra T, Lekang O. Use of residual acid phosphatase activity in heat-processed atlantic cod (Gadus morhua) for estimating thermal load. J Food Prot 2010; 73:923-31. [PMID: 20501044 DOI: 10.4315/0362-028x-73.5.923] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Farmed Atlantic cod muscle tissue was heated isothermally at temperatures of 56 to 68 degrees C for 15 s to 25.5 min. Extracts from the heat-treated samples were prepared by mixing with Triton X-100 (1:9, wt/wt) and subsequent centrifugation. Residual acid phosphatase (ACP) activity was measured, and the inactivation was modeled in two phases. Mean (+/-standard error) kinetic parameters of thermal inactivation were determined as D(60 degrees C) = 34.93 +/- 2.02 min and z = 22.01 +/- 4.10 degrees C for short heating times and D(60 degrees C) = 3.19 +/- 0.11 min and z = 6.31 +/- 0.51 degrees C for heating times longer than 100 s. The data support the use of residual ACP activity for modeling a 6-log inactivation of Listeria monocytogenes at 60 degrees C but only a 4-log inactivation at 70 degrees C. Extracts prepared from raw muscle and subsequently heated isothermally at temperatures of 54 to 70 degrees C for 2 to 51 min were used to obtain kinetic parameters D(60 degrees C) = 7.98 +/- 1.11 min and z = 6.92 +/- 0.07 degrees C. A short initial drop in ACP activity was observed in raw cod muscle during freezing and cold storage. Subsequently, the activity was stable for 24 months. ACP activity in raw cod muscle did not seem to be influenced by gender, season, or brining with different levels of salt and phosphates. No other factors that could inactivate ACP were found, and usual activity of 2.54 +/- 0.02 Abs/(min*g sample) can be expected in frozen and thawed farmed cod muscle.
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Affiliation(s)
- D Skipnes
- Nofima Norconserv AS, Richard Johnsens gt. 4, N-4021 Stavanger, Norway.
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Prevalence, persistence and control of Salmonella and Listeria in shrimp and shrimp products: A review. Food Control 2010. [DOI: 10.1016/j.foodcont.2009.06.020] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Olesen I, Thorsen L, Jespersen L. Relative transcription of Listeria monocytogenes virulence genes in liver pâtés with varying NaCl content. Int J Food Microbiol 2010; 141 Suppl 1:S60-8. [PMID: 20206397 DOI: 10.1016/j.ijfoodmicro.2010.01.042] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 01/27/2010] [Accepted: 01/29/2010] [Indexed: 01/20/2023]
Abstract
Quantitative real time polymerase chain reaction (qRT PCR) was used to compare the relative transcription of prfA, inlA, sigB and clpC for three Listeria monocytogenes strains after incubation in i) a standard liver pâté versus brain heart infusion (BHI) broth and ii) the standard liver pâté versus three liver pâtés with reduced NaCl content of which one also has been supplied with organic acids (Ca-acetate and Ca-lactate). The three strains (EGD-e: reference strain; O57: more NaCl sensitive; 6896: more NaCl tolerant) were selected out of twelve strains based on their growth in BHI broth adjusted to 6%, 8%, 10% (w/v) NaCl. The three strains were spiked into the liver pâtés (10(9) cfu/g) and the BHI (10(9) cfu/ml) and incubated for 48 h at 7 degrees C; all incubation conditions supported growth of the strains. Extraction of intact listerial RNA from the liver pâtés was complicated by the complexity of the liver pâté matrix. However, a method has been optimized and described, and the quality of RNA extracted from liver pâtés was equal to the quality of RNA extracted from BHI. The amplification efficiencies of the six genes used for the transcription analyses (the four target genes and two reference genes, gap and rpoB) were within the acceptable range from 90% to 110% for all three strains in both liver pâté and BHI. Comparison of the three strains after incubation in the standard liver pâté and BHI showed that the relative transcription of prfA for O57 and the relative transcription of inlA and sigB for both O57 and 6896 were significantly higher when the strains were grown in BHI compared to the standard liver pâté. Reducing the NaCl content of the standard liver pâté did not change relative transcription levels of prfA, inlA, sigB or clpC (except for prfA in O57 and sigB in 6896). However, the presence of Ca-acetate and Ca-lactate induced relative transcription of the stress response gene, clpC, for all three strains. This study demonstrates that relative microbial gene transcription can be measured in complex food matrices and points to the need for designing experimental set-ups in real food matrices to replace the laboratory model systems. With respect to L. monocytogenes, it seems that the NaCl content of liver pâté can be lowered within the investigated range without significant changes in relative virulence gene transcription while more caution should be taken when adding organic acids such as acetate and lactate.
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Affiliation(s)
- Inger Olesen
- Department of Food Science, Faculty of Life Sciences, University of Copenhagen, Frederiksberg C, Denmark.
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Jeya Shakila R, Jeyasekaran G, Vijayakumar A, Sukumar D. Microbiological quality of sous-vide cook chill fish cakes during chilled storage (3 °C). Int J Food Sci Technol 2009. [DOI: 10.1111/j.1365-2621.2009.02047.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gottlieb CT, Thomsen LE, Ingmer H, Mygind PH, Kristensen HH, Gram L. Antimicrobial peptides effectively kill a broad spectrum of Listeria monocytogenes and Staphylococcus aureus strains independently of origin, sub-type, or virulence factor expression. BMC Microbiol 2008; 8:205. [PMID: 19036162 PMCID: PMC2639596 DOI: 10.1186/1471-2180-8-205] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 11/26/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Host defense peptides (HDPs), or antimicrobial peptides (AMPs), are important components of the innate immune system that bacterial pathogens must overcome to establish an infection and HDPs have been suggested as novel antimicrobial therapeutics in treatment of infectious diseases. Hence it is important to determine the natural variation in susceptibility to HDPs to ensure a successful use in clinical treatment regimes. RESULTS Strains of two human bacterial pathogens, Listeria monocytogenes and Staphylococcus aureus, were selected to cover a wide range of origin, sub-type, and phenotypic behavior. Strains within each species were equally sensitive to HDPs and oxidative stress representing important components of the innate immune defense system. Four non-human peptides (protamine, plectasin, novicidin, and novispirin G10) were similar in activity profile (MIC value spectrum) to the human beta-defensin 3 (HBD-3). All strains were inhibited by concentrations of hydrogen peroxide between 0.1% - 1.0%. Sub-selections of both species differed in expression of several virulence-related factors and in their ability to survive in human whole blood and kill the nematode virulence model Caenorhabditis elegans. For L. monocytogenes, proliferation in whole blood was paralleled by high invasion in Caco-2 cells and fast killing of C. elegans, however, no such pattern in phenotypic behavior was observed for S. aureus and none of the phenotypic differences were correlated to sensitivity to HDPs. CONCLUSION Strains of L. monocytogenes and S. aureus were within each species equally sensitive to a range of HDPs despite variations in subtype, origin, and phenotypic behavior. Our results suggest that therapeutic use of HDPs will not be hampered by occurrence of naturally tolerant strains of the two species investigated in the present study.
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Affiliation(s)
- Caroline Trebbien Gottlieb
- National Institute of Aquatic Resources, Technical University of Denmark, Søltofts Plads, Bldg, 221, DK-2800 Kgs,, Lyngby, Denmark.
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31
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Response to the questions posed by the Food and Drug Administration and the National Marine Fisheries Service regarding determination of cooking parameters for safe seafood for consumers. J Food Prot 2008; 71:1287-308. [PMID: 18592762 DOI: 10.4315/0362-028x-71.6.1287] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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32
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Shin JH, Kang DH, Rasco B. Effect of Different Packaging Methods and Storage Temperatures on the Growth ofListeria monocytogenesin Raw and Hot Smoked Rainbow Trout (Oncorhynchus mykiss). JOURNAL OF AQUATIC FOOD PRODUCT TECHNOLOGY 2008. [DOI: 10.1080/10498850801937125] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Jørgensen F, Stephens P, Knøchel S. The effect of osmotic shock and subsequent adaptation on the thermotolerance and cell morphology ofListeria monocytogenes. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1365-2672.1995.tb03137.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Skipnes D, Van der Plancken I, Van Loey A, Hendrickx ME. Kinetics of heat denaturation of proteins from farmed Atlantic cod (Gadus morhua). J FOOD ENG 2008. [DOI: 10.1016/j.jfoodeng.2007.06.030] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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35
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Kışla D, Üzgün Y, Demirhisar MA. Incidence and sources of Listeria monocytogenes in a traditional hot-smoked rainbow trout processing plant in Turkey. Int J Food Sci Technol 2007. [DOI: 10.1111/j.1365-2621.2007.01620.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Jensen A, Larsen MH, Ingmer H, Vogel BF, Gram L. Sodium chloride enhances adherence and aggregation and strain variation influences invasiveness of Listeria monocytogenes strains. J Food Prot 2007; 70:592-9. [PMID: 17388046 DOI: 10.4315/0362-028x-70.3.592] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Some subtypes of Listeria monocytogenes can persist in the food-processing industry, but the reasons for such persistence are not known. In the present study, 10 strains of L. monocytogenes representing known persistent randomly amplified polymorphic DNA (RAPD) types from fish processing plants were compared to eight strains of different RAPD type and origin (clinical, food, and animal). All 18 strains of L. monocytogenes had similar growth patterns at different temperatures (5 or 37 degrees C) or different salinities (0.5 or 5% NaCl), and all strains formed a thin layer of adhered cells on a plastic surface when cultured in tryptone soya broth (TSB) with a total of 1% glucose. Many ready-to-eat foods, such as cold-smoked fish, contain NaCl at concentrations of 2 to 5%, and NaCl is present in the processing environment. Adding NaCl to TSB changed the adhesion patterns of all strains, and all adhered better when NaCl was added. Also, the addition of NaCl caused a marked aggregation of 13 of the strains; however, 5 of the 18 strains did not aggregate in the presence of up to 5% NaCl. The aggregates stuck to the plastic surface, and this occurred in all but one of the persistent RAPD types. Four strains represented one particular RAPD type that has been isolated as a persistent RAPD type in several fish processing plants for up to 10 years. Because this RAPD type often can contaminate fish products, it is important to address its potential virulence. The 18 strains differed markedly in their ability to invade Caco-2 cells, and the four strains representing the universal persistent RAPD type were the least invasive (10(2) to 10(3) CFU/ml), whereas other strains invaded Caco-2 cells at levels of 10(4) to 10(5) CFU/ml. Five of the 18 strains belonged to the genetic lineage 1 and were the most invasive. Although the most commonly isolated persistent RAPD type was low invasive, it is important to understand why moderate salinity facilitates aggregation and biofilm formation, for this understanding can be beneficial in developing procedures to reduce processing plant contamination.
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Affiliation(s)
- Anne Jensen
- Danish Institute for Fisheries Research, Department of Seafood Research, Søltofts Plads, DTU bldg. 221, DK-2800 Kgs. Lyngby, Denmark.
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Basic parameters of a new production technology for “gyros”. A shelf life study of the product at 4°C. J FOOD ENG 2007. [DOI: 10.1016/j.jfoodeng.2006.02.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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38
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Montero P, Gómez-Estaca J, Gómez-Guillén MC. Influence of salt, smoke, and high pressure on growth of Listeria monocytogenes and spoilage microflora in cold-smoked dolphinfish (Coryphaena hippurus). J Food Prot 2007; 70:399-404. [PMID: 17340875 DOI: 10.4315/0362-028x-70.2.399] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The effects of different salting and smoking conditions on the growth of Listeria monocytogenes in cold-smoked dolphinfish (Coryphaena hippurus) fillets were evaluated. High concentrations of phenol (72.47 ppm) and salt (3.25%) in muscle inhibited L. monocytogenes growth in smoked fish stored at 20 degrees C for 4 days. The antibacterial effect of high pressure in cold-smoked dolphinfish during long-term chilled (5 degrees C) storage was evaluated in fillets prepared according to two different sets of salting and smoking conditions. Combining the milder salting and smoking conditions (1.97% salt and 42 ppm phenol) with a high pressure treatment of 300 MPa at 20 degrees C for 15 min sufficed to exert a bacteriostatic effect on the total viable bacteria, total lactic acid bacteria, and L. monocytogenes. However, in fillets prepared using the more severe salting and smoking conditions (2.93% salt and 82 ppm phenol), pressurization kept L. monocytogenes counts under the detection limit throughout 100 days of storage. A similar effect was obtained by dosing the fillets with nisin. No luminescent bacteria, hydrogen sulfide-producing bacteria, or Enterobacteriaceae were found in any of the fillets produced using either of the two sets of processing conditions.
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Affiliation(s)
- P Montero
- Instituto del Frío, Consejo Superior de Investigaciones Científicas, José Antonio Novais 10, 28040 Madrid, Spain
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39
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Johnsen SO, Skipnes D, Skåra T, Hendrickx ME. Thermal Inactivation kinetics of acid phosphatase (ACP) in cod (Gadus morhua). Eur Food Res Technol 2006. [DOI: 10.1007/s00217-006-0433-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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40
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Kennedy J, Blair IS, McDowell DA, Bolton DJ. An investigation of the thermal inactivation of Staphylococcus aureus and the potential for increased thermotolerance as a result of chilled storage. J Appl Microbiol 2005; 99:1229-35. [PMID: 16238754 DOI: 10.1111/j.1365-2672.2005.02697.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS The aims of this study were; (i) to provide thermal inactivation data for Staphylococcus aureus; (ii) to examine the kinetics, including decimal reduction times (D-value) and rate constants (k), that describe the thermal inactivation of Staph. aureus and to compare two different methods of calculating D-values and (iii) to determine whether or not chilled storage would toughen these microorganisms resulting in increased thermotolerance. METHODS AND RESULTS Isolates of Staph. aureus recovered from domestic refrigerators were grown in shaken culture for 8 h at 37 degrees C, recovered and washed by centrifugation and combined to form a cocktail of five strains. Samples from this cocktail were (a) heat treated at 50, 55 and 60 degrees C or (b) held under simulated domestic refrigeration conditions for 72 h and then heat treated as above. The numbers of Staph. aureus in heat treated and chill held, heat treated samples were enumerated by direct selective plating onto Baird Parker Agar (BPA) and recovery plating on Tryptone Soya Agar (TSA) subsequently overlaid with BPA. D-values were obtained using two different methods both of which may be used when the thermal inactivation follows first order kinetics. In the first method D-values are obtained by plotting the Log(10) of the surviving cells against time and using the equation D = -1/slope. The second method uses the rate constant (k) which is obtained from the slope of a plot of ln N/N(0)vs time and D is obtained using the equation D = 2.303 k(-1). D(50), D(55) and D(60) values ranged from 94.3 to 127.9 min, 13 to 21.7 min and 4.8 to 6.5 min. Prechilling did not enhance thermal resistance. The method of calculation did not affect the D-values obtained because the thermal inactivation of Staph. aureus in this study followed first order kinetics with r(2) values of 0.91-0.99. CONCLUSIONS The thermal inactivation of Staph. aureus in tryptone soya broth (TSB) follows first order kinetics and in general chilling of these bacteria does not increase the resistance to thermal destruction during subsequent thermal processes such as cooking. SIGNIFICANCE AND IMPACT OF THE STUDY This study provides much needed data on the thermal resistance of Staph. aureus and validates chilling as a food storage activity which does not cause toughening of the microorganisms to subsequent cooking. However, the data generated strongly suggests that Staph. aureus is more thermotolerant than Listeria monocytogenes and should be used as the target microorganism in designing mild thermal treatments for food, in which case the current recommendations for pasteurization (70 degrees C for 2 min, minimum) should be revised.
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Affiliation(s)
- J Kennedy
- Foods Safety Department, Teagasc-- The National Food Centre, Ashtown, Ireland
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41
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Francis G, O’Beirne D. Variation among strains of Listeria monocytogenes: differences in survival on packaged vegetables and in response to heat and acid conditions. Food Control 2005. [DOI: 10.1016/j.foodcont.2004.06.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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42
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Miettinen H, Arvola A, Wirtanen G. Pasteurization of rainbow trout roe: Listeria monocytogenes and sensory analyses. J Food Prot 2005; 68:1641-7. [PMID: 21132972 DOI: 10.4315/0362-028x-68.8.1641] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
D- and z-values for a mixture of four Listeria monocytogenes strains originating from the roe of different fish species were determined in rainbow trout (Oncorhynchus mykiss) roe. The D60- and D63-values obtained were 1.60 and 0.44 min, respectively, and the z-value was 5.36 degrees C accordingly. In pilot-scale experiments, rainbow trout roe (100 g) was vacuum packaged into glass jars and pasteurized both at 62 and 65 degrees C for 10 min. These treatments were enough to destroy 10(8) CFU/ g of L. monocytogenes cells, which was the highest possible Listeria cell count to grow in roe. On the basis of the determined z-value and calculation of pasteurization values, these experimental pasteurizations were found to theoretically destroy at least 45 log units of L. monocytogenes cells in rainbow trout roe. In addition, these pasteurization treatments did not significantly affect the sensory quality of the roe. The sensory quality of pasteurized vacuum-packaged rainbow trout roe stored at 3 degrees C was evaluated as good after 6 months of storage and not statistically different from the control that was frozen from the same roe lot as the pasteurized roe samples. Pasteurization of rainbow trout roe was proven to be an appropriate method for ensuring product safety with regard to L. monocytogenes and to stabilizing the sensory and microbial quality of roe. However, the safety risk caused by spore-forming bacteria still exists in pasteurized roe. Therefore, it has to be stored below 3 degrees C.
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Nilsson L, Hansen TB, Garrido P, Buchrieser C, Glaser P, Knøchel S, Gram L, Gravesen A. Growth inhibition of Listeria monocytogenes by a nonbacteriocinogenic Carnobacterium piscicola. J Appl Microbiol 2005; 98:172-83. [PMID: 15610430 DOI: 10.1111/j.1365-2672.2004.02438.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS This study elucidates the mechanisms by which a nonbacteriocinogenic Carnobacterium piscicola inhibits growth of Listeria monocytogenes. METHODS AND RESULTS Listeria monocytogenes was exposed to live cultures of a bacteriocin-negative variant of C. piscicola A9b in co-culture, in a diffusion chamber system, and to a cell-free supernatant. Suppression of maximum cell density (0-3.5 log units) of L. monocytogenes was proportional to initial levels of C. pisciola (10(3)-10(7) CFU ml(-1)). Cell-to-cell contact was not required to cause inhibition. The cell-free C. piscicola supernatant caused a decrease in L. monocytogenes maximum cell density, which was abolished by glucose addition but not by amino acid, vitamin or mineral addition. The fermentate also gave rise to a longer lag phase and a reduction in growth rate. These effects were independent of glucose and may have been caused by acetate production by C. piscicola. 2D gel-electrophoretic patterns of L. monocytogenes exposed to C. piscicola or to L. monocytogenes fermentate did not differ. Treatment with C. piscicola fermentate resulted in down-regulation (twofold) of genes involved in purine- or pyrimidine metabolism, and up-regulation (twofold) of genes from the regulon for vitamin B12 biosynthesis and propanediol and ethanolamine utilization. CONCLUSIONS A nonbacteriocinogenic C. piscicola reduced growth of L. monocytogenes partly by glucose depletion. SIGNIFICANCE AND IMPACT OF THE STUDY Understanding the mechanism of microbial interaction enhances prediction of growth in mixed communities as well as use of bioprotective principles for food preservation.
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Affiliation(s)
- L Nilsson
- Department of Seafood Research, Danish Institute for Fisheries Research, Søltofts Plads, c/o Technical University of Denmark, Lyngby, Denmark
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44
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Microbiological safety and sensory characteristics of salmon slices processed by the sous vide method. Food Control 2005. [DOI: 10.1016/j.foodcont.2003.11.011] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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GARCÍA-LINARES M, GONZALEZ-FANDOS E, GARCÍA-FERNÁNDEZ M, GARCÍA-ARIAS M. MICROBIOLOGICAL AND NUTRITIONAL QUALITY OF SOUS VIDE OR TRADITIONALLY PROCESSED FISH: INFLUENCE OF FAT CONTENT. J FOOD QUALITY 2004. [DOI: 10.1111/j.1745-4557.2004.00676.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Murphy RY, Osaili T, Duncan LK, Marcy JA. Thermal Inactivation of Salmonella and Listeria Monocytogenes in Ground Chicken Thigh/Leg Meat and Skin. Poult Sci 2004; 83:1218-25. [PMID: 15285516 DOI: 10.1093/ps/83.7.1218] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Thermal inactivation D and z values of Salmonella and Listeria monocytogenes were obtained for chicken thigh and leg meat and skin. The D values of Salmonella at 55 to 70 degrees C were 43.33 to 0.07 min in the meat and 43.76 to 0.09 min in the skin. The D values of L. monocytogenes at 55 to 70 degrees C were 38.94 to 0.04 min in the meat and 34.05 to 0.05 min in the skin. The z value of Salmonella was 5.34 degrees C in the meat and 5.56 degrees C in the skin. The z value of L. monocytogenes was 5.08 degrees C in the meat and 5.27 degrees C in the skin. For Salmonella or L. monocytogenes, the z value of the meat was not different from that of skin. However, the z value of Salmonella in meat or skin was different from that of L. monocytogenes in meat or skin. The z value of Salmonella or L. monocytogenes in chicken thigh and leg meat was different from that in the skin. The results from this study are useful for predicting process lethality of Salmonella and L. monocytogenes in products that contain chicken thigh and leg meat or skin.
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Affiliation(s)
- R Y Murphy
- Department of Biological and Agricultural Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA.
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Gravesen A, Kallipolitis B, Holmstrøm K, Høiby PE, Ramnath M, Knøchel S. pbp2229-mediated nisin resistance mechanism in Listeria monocytogenes confers cross-protection to class IIa bacteriocins and affects virulence gene expression. Appl Environ Microbiol 2004; 70:1669-79. [PMID: 15006792 PMCID: PMC368357 DOI: 10.1128/aem.70.3.1669-1679.2004] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2003] [Accepted: 11/21/2003] [Indexed: 11/20/2022] Open
Abstract
It was previously shown that enhanced nisin resistance in some mutants was associated with increased expression of three genes, pbp2229, hpk1021, and lmo2487, encoding a penicillin-binding protein, a histidine kinase, and a protein of unknown function, respectively. In the present work, we determined the direct role of the three genes in nisin resistance. Interruption of pbp2229 and hpk1021 eliminated the nisin resistance phenotype. Interruption of hpk1021 additionally abolished the increase in pbp2229 expression. The results indicate that this nisin resistance mechanism is caused directly by the increase in pbp2229 expression, which in turn is brought about by the increase in hpk1021 expression. We also found a degree of cross-protection between nisin and class IIa bacteriocins and investigated possible mechanisms. The expression of virulence genes in one nisin-resistant mutant and two class IIa bacteriocin-resistant mutants of the same wild-type strain was analyzed, and each mutant consistently showed either an increase or a decrease in the expression of virulence genes (prfA-regulated as well as prfA-independent genes). Although the changes mostly were moderate, the consistency indicates that a mutant-specific change in virulence may occur concomitantly with bacteriocin resistance development.
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Affiliation(s)
- Anne Gravesen
- Department of Dairy and Food Science, Centre for Advanced Food Studies, LMC, The Royal Veterinary and Agricultural University, DK-1958 Frederiksberg C, Denmark.
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Nilsson L, Ng YY, Christiansen JN, Jørgensen BL, Grótinum D, Gram L. The contribution of bacteriocin to inhibition of Listeria monocytogenes by Carnobacterium piscicola strains in cold-smoked salmon systems. J Appl Microbiol 2004; 96:133-43. [PMID: 14678166 DOI: 10.1046/j.1365-2672.2003.02129.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To study the importance of bacteriocin production for the antilisterial effect of a bacteriocinogenic Carnobacterium piscicola strain A9b on growth of Listeria monocytogenes in broth and cold-smoked salmon systems. METHODS AND RESULTS Acriflavin treatment of strain A9b resulted in loss of bacteriocin production and of immunity to carnobacteriocin B2. Two plasmids present in the wild-type were lost in the variant that was also more sensitive to bavaricin and leucocin A than the wild-type indicating cross-resistance to class IIa bacteriocins. The growth rate of the bac- mutant was higher than that of the wild-type at 5 and 37 degrees C but not at 25 or 30 degrees C. In salmon juice the maximum cell density of L. monocytogenes was suppressed 3 and 6 log by co-culture with C. piscicola A9b bac- and bac+, respectively, as compared with the control. Sterile filtered cultures of C. piscicola A9b bac- caused a limited suppression of the maximum cell density of L. monocytogenes similar to that observed when sterile buffer was added in equal amounts. Semi-purified carnobacteriocin B2 caused a 3.5 log decline in viable cell count after 6 day of incubation in cold-smoked salmon juice at 5 degrees C. High resistance level to carnobacteriocin B2 was observed for L. monocytogenes cells exposed to semi-purified and in situ produced carnobacteriocin B2. CONCLUSIONS The presence of bacteriocin production in C. piscicola enhances its inhibition of L. monocytogenes. SIGNIFICANCE AND IMPACT OF THE STUDY Due to the emergence of resistance, a bacteriocin negative lactic acid bacteria may be more suited for practical use as a bioprotective agent against L. monocytogenes in ready-to-eat foods.
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Affiliation(s)
- L Nilsson
- Department of Seafood Research, Danish Institute for Fisheries Research, Lyngby, Denmark
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Bolton DJ, Pearce R, Sheridan JJ, McDowell DA, Blair IS. Decontamination of pork carcasses during scalding and the prevention of Salmonella cross-contamination. J Appl Microbiol 2003; 94:1036-42. [PMID: 12752812 DOI: 10.1046/j.1365-2672.2003.01938.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS The objective of this study was to establish critical temperature limits to prevent cross-contamination of pork carcasses during scalding. METHODS AND RESULTS Mixtures of antibiotic-resistant mutants of Salmonella species were heat treated at 50, 55 and 60 degrees C in samples of commercial scald tank water. Surviving cell numbers were estimated by plating treated suspensions on (i). tryptone soya agar (TSA) and (ii). on TSA, overlaid with brilliant green agar plus nalidixic acid and streptomycin sulphate and used to estimate D-values for the treated mixed cell suspensions. CONCLUSIONS A time-temperature combination of 1.4 min at 60 degrees C is required to achieve a 1 log reduction in Salmonella in scald tank water. The predicted equivalent at 65 degrees C is 0.18 min. SIGNIFICANCE AND IMPACT OF THE STUDY This study provides data and a model to enable pork processors to identify and apply processing parameters to limit the risks of transfer of Salmonella between pig carcasses during commercial scalding operations.
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Affiliation(s)
- D J Bolton
- The National Food Centre, Ashtown, Dublin 15, Republic of Ireland.
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Ramnath M, Rechinger KB, Jänsch L, Hastings JW, Knøchel S, Gravesen A. Development of a Listeria monocytogenes EGDe partial proteome reference map and comparison with the protein profiles of food isolates. Appl Environ Microbiol 2003; 69:3368-76. [PMID: 12788738 PMCID: PMC161492 DOI: 10.1128/aem.69.6.3368-3376.2003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A partially annotated proteome reference map of the food pathogen Listeria monocytogenes was developed for exponentially growing cells under standardized, optimal conditions by using the sequenced strain EGDe (serotype 1/2a) as a model organism. The map was developed by using a reproducible total protein extraction and two-dimensional (2-D) polyacrylamide gel electrophoresis analysis procedure, and it contained 33 identified proteins representing the four main protein functional classes. In order to facilitate analysis of membrane proteins, a protein compartmentalization procedure was assessed. The method used provided partial fractionation of membrane and cytosolic proteins. The total protein 2-D profiles of three serotype 1/2a strains and one serotype 1/2b strain isolated from food were compared to the L. monocytogenes EGDe proteome. An average of 13% of the major protein spots in the food strain proteomes were not matched in the strain EGDe proteome. The variation was greater for the less intense spots, and on average 28% of these spots were not matched. Two of the proteins identified in L. monocytogenes EGDe were missing in one or more of the food isolates. These two proteins were proteins involved in the main glycolytic pathway and in metabolism of coenzymes and prosthetic groups. The two corresponding genes were found by PCR amplification to be present in the four food isolates. Our results show that the L. monocytogenes EGDe reference map is a valuable starting point for analyses of strains having various origins and could be useful for analyzing the proteomes of different isolates of this pathogen.
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Affiliation(s)
- Manilduth Ramnath
- Department of Biochemistry, University of Stellenbosch, 7602 Matieland, South Africa
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