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Behavior of Salmonella spp., Listeria monocytogenes, and Staphylococcus aureus in Chouri├žo de Vinho, a dry fermented sausage made from wine-marinated meat.

https://arctichealth.org/en/permalink/ahliterature114836
Source
J Food Prot. 2013 Apr;76(4):588-94
Publication Type
Article
Date
Apr-2013
Author
J García Díez
L. Patarata
Author Affiliation
Universidade de Trás-os-Montes e Alto Douro, Centre of Studies in Animal and Veterinary Science, 5001-801 Vila Real, Portugal.
Source
J Food Prot. 2013 Apr;76(4):588-94
Date
Apr-2013
Language
English
Publication Type
Article
Keywords
Animals
Colony Count, Microbial
Consumer Product Safety
Fermentation
Food Contamination - analysis - prevention & control
Food Handling - methods
Food Microbiology
Humans
Listeria monocytogenes - growth & development
Meat Products - microbiology
Salmonella - growth & development
Staphylococcus aureus - growth & development
Abstract
Portuguese chouriço de vinho is made by drying coarsely minced meat and fat that has been previously marinated with wine (usually red), salt, and garlic for 1 to 2 days at a low temperature (4 to 8 °C). This procedure may improve the microbiological safety of the product. The aim of this study was to evaluate the behavior of three pathogens in this product, Salmonella spp., Listeria monocytogenes, and Staphylococcus aureus, to establish the minimum period of drying and maturation necessary to render safe products. The pathogens were inoculated in the chouriço de vinho batter. A factorial design was used to study the following variables in the fermentation process: (i) the presence or absence of an indigenous Lactobacillus sakei starter culture; (ii) the presence or absence of fermentable carbohydrates; and (iii) the salt level (1.5 or 3%). The samples were analyzed 24 h after the preparation of the batter (at stuffing); after 7, 15, and 30 days of drying; and after 30 days of storage at 4 °C under vacuum. Under all of the conditions studied, the levels of the three pathogens decreased during the drying period. In the early stages of drying, the addition of L. sakei starter culture and/or carbohydrates resulted in lower levels of gram-positive pathogens. After 15 days of drying, populations of all pathogens decreased by ca. 2 log in all samples. At that sampling time, L. monocytogenes was undetectable in the chouriço de vinho with L. sakei starter culture and carbohydrates. The mean count of S. aureus after 15 days of drying was below 1 log CFU/g. After 30 days of drying, no pathogens were detected. The drying period could be shortened to 15 days when considering only the gram-positive pathogens studied and the use of a starter culture and carbohydrates. Due to the low infective dose of Salmonella spp., the product should be considered safe after 30 days, when this pathogen became undetectable.
PubMed ID
23575119 View in PubMed
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Coliforms and prevalence of Escherichia coli and foodborne pathogens on minimally processed spinach in two packing plants.

https://arctichealth.org/en/permalink/ahliterature152389
Source
J Food Prot. 2008 Dec;71(12):2398-403
Publication Type
Article
Date
Dec-2008
Author
Sanja Ilic
Joseph Odomeru
Jeffrey T LeJeune
Author Affiliation
Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691, USA.
Source
J Food Prot. 2008 Dec;71(12):2398-403
Date
Dec-2008
Language
English
Publication Type
Article
Keywords
Canada
Colony Count, Microbial
Enterobacteriaceae - isolation & purification
Escherichia coli - isolation & purification
Escherichia coli O157 - isolation & purification
Food contamination - analysis
Food Handling - methods
Food-Processing Industry - standards
Humans
Listeria monocytogenes - isolation & purification
Prevalence
Risk assessment
Salmonella - isolation & purification
Shigella - isolation & purification
Spinacia oleracea - microbiology
United States
Abstract
Minimally processed spinach has been recently associated with outbreaks of foodborne illnesses. This study investigated the effect of commercial minimal processing of spinach on the coliform and Escherichia coli counts and the prevalence of E. coli O157:H7, Salmonella, Shigella spp., and Listeria monocytogenes on two types of spinach before and after minimal processing. A total of 1,356 spinach samples (baby spinach, n = 574; savoy spinach, n = 782) were collected daily in two processing plants over a period of 14 months. Raw spinach originated from nine farms in the United States and three farms in Canada. Overall, the proportion of samples positive for coliforms increased from 53% before minimal processing to 79% after minimal processing (P 0.1) was observed. E. coli O157:H7 and Shigella spp. were not isolated from any of the samples. Salmonella and L. monocytogenes were isolated from 0.4 and 0.7% of samples, respectively. Results demonstrate that commercial minimal processing of spinach based on monitored chlorine washing and drying may not decrease microbial load on spinach leaves as expected. Further research is needed to identify the most appropriate measures to control food safety risk under commercial minimal processing of fresh vegetables.
PubMed ID
19244890 View in PubMed
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Effect of potassium lactate and a potassium lactate-sodium diacetate blend on Listeria monocytogenes growth in modified atmosphere packaged sliced ham.

https://arctichealth.org/en/permalink/ahliterature160564
Source
J Food Prot. 2007 Oct;70(10):2297-305
Publication Type
Article
Date
Oct-2007
Author
L A Mellefont
T. Ross
Author Affiliation
Australian Food Safety Centre of Excellence, Tasmanian Institute of Agricultural Research, School of Agricultural Science, University of Tasmania, Private Bag 54, Hobart 7001, Tasmania, Australia. lyndal.mellefont@utas.edu.au
Source
J Food Prot. 2007 Oct;70(10):2297-305
Date
Oct-2007
Language
English
Publication Type
Article
Keywords
Animals
Colony Count, Microbial
Food contamination - analysis
Food Handling - methods
Food Microbiology
Food Packaging - methods
Food Preservation - methods
Food Preservatives - pharmacology
Humans
Lactates - pharmacology
Listeria monocytogenes - drug effects - growth & development
Meat Products - microbiology
Salmonella Food Poisoning - epidemiology - prevention & control
Sodium Acetate - pharmacology
Swine
Temperature
Time Factors
Abstract
Two commercially available organic acid salts, potassium lactate (PURASAL HiPure P) and a potassium lactate-sodium diacetate blend (PURASAL Opti. Form PD 4), were assessed as potential inhibitors of Listeria monocytogenes growth in modified atmosphere packaged (MAP) sliced ham in challenge studies. The influence of the initial inoculation level of L. monocytogenes (10(1) or 10(3) CFU g(-1)) and storage temperature (4 or 8 degrees C) was also examined. The addition of either organic acid salt to MAP sliced ham strongly inhibited the growth of L. monocytogenes during the normal shelf life of the product under ideal refrigeration conditions (4 degrees C) and even under abusive temperature conditions (i.e., 8 degrees C). During the challenge studies and in the absence of either organic acid salt, L. monocytogenes numbers increased by 1000-fold after 20 days at 8 degrees C and 10-fold after 42 days at 4 degrees C. Both organic acid salt treatments were found to be listeriostatic rather than listericidal. The addition of either organic acid salt to the MAP ham also reduced the growth of indigenous microflora, i.e., aerobic microflora and lactic acid bacteria. The influence of these compounds on the risk of listeriosis in relation to product shelf life is discussed.
PubMed ID
17969611 View in PubMed
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Efficacy of neutral electrolyzed water (NEW) for reducing microbial contamination on minimally-processed vegetables.

https://arctichealth.org/en/permalink/ahliterature159055
Source
Int J Food Microbiol. 2008 Mar 31;123(1-2):151-8
Publication Type
Article
Date
Mar-31-2008
Author
Maribel Abadias
Josep Usall
Márcia Oliveira
Isabel Alegre
Inmaculada Viñas
Author Affiliation
IRTA, Centre UdL-IRTA, XaRTA-Postharvest, 191 Rovira Roure, 25198-Lleida, Catalonia, Spain. isabel.abadias@irta.cat
Source
Int J Food Microbiol. 2008 Mar 31;123(1-2):151-8
Date
Mar-31-2008
Language
English
Publication Type
Article
Keywords
Colony Count, Microbial
Consumer Product Safety
Disinfectants - pharmacology
Dose-Response Relationship, Drug
Escherichia coli O157 - drug effects - growth & development
Food Contamination - analysis - prevention & control
Food Handling - methods
Food Microbiology
Humans
Hydrogen Peroxide - pharmacology
Lettuce - microbiology
Listeria monocytogenes - drug effects - growth & development
Pectobacterium carotovorum - drug effects - growth & development
Salmonella - drug effects - growth & development
Temperature
Time Factors
Vegetables - microbiology
Abstract
Consumption of minimally-processed, or fresh-cut, fruit and vegetables has rapidly increased in recent years, but there have also been several reported outbreaks associated with the consumption of these products. Sodium hypochlorite is currently the most widespread disinfectant used by fresh-cut industries. Neutral electrolyzed water (NEW) is a novel disinfection system that could represent an alternative to sodium hypochlorite. The aim of the study was to determine whether NEW could replace sodium hypochlorite in the fresh-cut produce industry. The effects of NEW, applied in different concentrations, at different treatment temperatures and for different times, in the reduction of the foodborne pathogens Salmonella, Listeria monocytogenes and Escherichia coli O157:H7 and against the spoilage bacterium Erwinia carotovora were tested in lettuce. Lettuce was artificially inoculated by dipping it in a suspension of the studied pathogens at 10(8), 10(7) or 10(5) cfu ml(-1), depending on the assay. The NEW treatment was always compared with washing with deionized water and with a standard hypochlorite treatment. The effect of inoculum size was also studied. Finally, the effect of NEW on the indigenous microbiota of different packaged fresh-cut products was also determined. The bactericidal activity of diluted NEW (containing approximately 50 ppm of free chlorine, pH 8.60) against E. coli O157:H7, Salmonella, L. innocua and E. carotovora on lettuce was similar to that of chlorinated water (120 ppm of free chlorine) with reductions of 1-2 log units. There were generally no significant differences when treating lettuce with NEW for 1 and 3 min. Neither inoculation dose (10(7) or 10(5) cfu ml(-1)) influenced the bacterial reduction achieved. Treating fresh-cut lettuce, carrot, endive, corn salad and 'Four seasons' salad with NEW 1:5 (containing about 50 ppm of free chlorine) was equally effective as applying chlorinated water at 120 ppm. Microbial reduction depended on the vegetable tested: NEW and sodium hypochlorite treatments were more effective on carrot and endive than on iceberg lettuce, 'Four seasons' salad and corn salad. The reductions of indigenous microbiota were smaller than those obtained with the artificially inoculated bacteria tested (0.5-1.2 log reduction). NEW seems to be a promising disinfection method as it would allow to reduce the amount of free chlorine used for the disinfection of fresh-cut produce by the food industry, as the same microbial reduction as sodium hypochlorite is obtained. This would constitute a safer, 'in situ', and easier to handle way of ensuring food safety.
PubMed ID
18237810 View in PubMed
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Pathogen survival in chorizos: ecological factors.

https://arctichealth.org/en/permalink/ahliterature169205
Source
J Food Prot. 2006 May;69(5):1087-95
Publication Type
Article
Date
May-2006
Author
Carrie M Hew
Maha N Hajmeer
Thomas B Farver
Hans P Riemann
James M Glover
Dean O Cliver
Author Affiliation
Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, California 95616, USA.
Source
J Food Prot. 2006 May;69(5):1087-95
Date
May-2006
Language
English
Publication Type
Article
Keywords
Animals
Colony Count, Microbial
Consumer Product Safety
Escherichia coli O157 - growth & development
Food contamination - analysis
Food Handling - methods
Food Microbiology
Humans
Listeria monocytogenes - growth & development
Meat Products - microbiology
Mexico
Salmonella - growth & development
Sodium Chloride - metabolism - pharmacology
Spices
Swine
Taste
Temperature
Time Factors
Water - metabolism
Abstract
This study addressed health risks from ethnic sausages produced on a small scale, without inspection, in California and elsewhere. Mexican-style chorizo, a raw pork sausage that is not cured, fermented, or smoked, was contaminated experimentally in the batter with Escherichia coli O157:H7, Listeria monocytogenes, or Salmonella serotypes and stuffed into natural casings. Formulations were based on a market survey in California. Physical parameters that were controlled were pH, water activity (a(w)), and storage temperature. The pH was adjusted with vinegar, stabilizing at 5.0 within 24 h. Initial a(w) levels adjusted with salt were 0.97, 0.95, 0.93, 0.90, and 0.85; levels declined with time because of evaporation. Pathogen numbers declined with storage up to 7 days, with few brief exceptions. Main effects and interactions of constant temperature and pH with declining a(w) on survival of the pathogens were determined. Maximum death rates occurred at higher a(w) for E. coli O157:H7 and Salmonella than for L. monocytogenes. Salt used to adjust a(w) affected palatability. Spices (black pepper, chili pepper, chili powder, cumin, garlic, guajillo pepper, oregano, and paprika) comprised another, potentially significant aspect of the sausage formulation. Some (notably black pepper and cumin) carried an indigenous microflora that contributed significantly to the microbial load of the sausage batter. Only undiluted fresh and powdered garlic exhibited a significant antimicrobial effect on the pathogens. Although each of the tested formulations caused death of the inoculated pathogens, none of the death rates was sufficiently rapid to ensure safety within the probable shelf life of the product.
PubMed ID
16715809 View in PubMed
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Prevalence and survival of Listeria monocytogenes in Danish aquatic and fish-processing environments.

https://arctichealth.org/en/permalink/ahliterature80547
Source
J Food Prot. 2006 Sep;69(9):2113-22
Publication Type
Article
Date
Sep-2006
Author
Hansen Cisse Hedegaard
Vogel Birte Fonnesbech
Gram Lone
Author Affiliation
Department of Seafood Research, Danish Institute for Fisheries Research, Søltofts Plads, DTU Building 221, DK-2800 Kgs. Lyngby, Denmark. chh@difres.dk
Source
J Food Prot. 2006 Sep;69(9):2113-22
Date
Sep-2006
Language
English
Publication Type
Article
Keywords
Animals
Aquaculture - standards
Consumer Product Safety
DNA, Bacterial - analysis
Denmark
Environmental Microbiology
Food contamination - analysis
Food Handling - methods
Food-Processing Industry - methods - standards
Humans
Listeria monocytogenes - growth & development - isolation & purification
Prevalence
Random Amplified Polymorphic DNA Technique
Seafood - microbiology
Water Microbiology
Abstract
Listeria monocytogenes contamination of ready-to-eat food products such as cold-smoked fish is often caused by pathogen subtypes persisting in food-processing environments. The purpose of the present study was to determine whether these L. monocytogenes subtypes can be found in the outside environment, i.e., outside food processing plants, and whether they survive better in the aquatic environment than do other strains. A total of 400 samples were collected from the outside environment, fish slaughterhouses, fish farms, and a smokehouse. L. monocytogenes was not detected in a freshwater stream, but prevalence increased with the degree of human activity: 2% in seawater fish farms, 10% in freshwater fish farms, 16% in fish slaughterhouses, and 68% in a fish smokehouse. The fish farms and slaughterhouses processed Danish rainbow trout, whereas the smokehouse was used for farm-raised Norwegian salmon. No variation with season was observed. Inside the processing plants, the pattern of randomly amplified polymorphic DNA (RAPD) types was homogeneous, but greater diversity existed among isolates from the outside environments. The RAPD type dominating the inside of the fish smokehouse was found only sporadically in outside environments. To examine survival in different environments, L. monocytogenes or Listeria innocua strains were inoculated into freshwater and saltwater microcosms. Pathogen counts decreased over time in Instant Ocean and remained constant in phosphate-buffered saline. In contrast, counts decreased rapidly in natural seawater and fresh water. The count reduction was much slower when the natural waters were autoclaved or filtered (0.2-microm pore size), indicating that the pathogen reduction in natural waters was attributable to a biological mechanism, e.g., protozoan grazing. A low prevalence of L. monocytogenes was found in the outside environment, and the bacteria did not survive well in natural environments. Therefore, L. monocytogenes in the outer environment associated with Danish fish processing is probably of minor importance to the environment inside a fish production plant.
PubMed ID
16995513 View in PubMed
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Prevalence of Listeria monocytogenes in, and microbiological and sensory quality of, rainbow trout, whitefish, and vendace roes from Finnish retail markets.

https://arctichealth.org/en/permalink/ahliterature183184
Source
J Food Prot. 2003 Oct;66(10):1832-9
Publication Type
Article
Date
Oct-2003
Author
Hanna Miettinen
Anne Arvola
Tiina Luoma
Gun Wirtanen
Author Affiliation
VTT Biotechnology, PO Box 1500, FIN-02044 VTT, Finland. hanna.miettinen@vtt.fi
Source
J Food Prot. 2003 Oct;66(10):1832-9
Date
Oct-2003
Language
English
Publication Type
Article
Keywords
Animals
Colony Count, Microbial
Consumer Product Safety
Finland
Fishes
Food contamination - analysis
Food Handling - methods
Food Microbiology
Frozen Foods - microbiology - standards
Humans
Listeria monocytogenes - isolation & purification
Oncorhynchus mykiss
Ovum - microbiology
Salmonidae
Seafood - microbiology - standards
Taste
Abstract
The prevalence of Listeria monocytogenes in retail roe, as well as the microbiological and sensory qualities of the roe, were studied for three fish species under three different storage conditions. A total of 147 Finnish rainbow trout (Oncorhynchus mykiss), whitefish (Coregonus lavaretus), vendace (Coregonus albula), and burbot (Lota lota) roe samples were bought fresh, frozen, or frozen-thawed from Finnish retail markets. The overall prevalence of L. monocytogenes was 5%; however, the prevalence of the pathogen in fresh roe was 18%. Fresh-bought roe tested positive for Listeria spp. and for L. monocytogenes, respectively, 5 and 20 times as often as did frozen and frozen-thawed roe products combined. The microbiological quality (analyzed as total aerobic heterotrophic bacteria and coliform bacteria) of 78% of the roe samples was unacceptable. Frozen roe samples were found to have the best microbiological quality. According to the results of a sensory evaluation, at least one sensory attribute (appearance, odor freshness, texture, and freshness of taste) was unacceptable for 29% of the roe samples studied. The sensory quality of roe samples bought fresh was better than that of roe samples bought frozen or frozen-thawed. From the results of this study, it is concluded that both the microbiological and the sensory qualities of roe at the retail level need to be improved.
PubMed ID
14572220 View in PubMed
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7 records – page 1 of 1.