Prevalence of Listeria monocytogenes and Salmonella in Ready-to-Eat Food in Catalonia, Spain

2008 ◽  
Vol 71 (4) ◽  
pp. 855-859 ◽  
Author(s):  
L. CABEDO ◽  
L. PICART i BARROT ◽  
A. TEIXIDÓ i CANELLES

Listeria monocytogenes and Salmonella are pathogenic bacteria that can contaminate food products during or after processing. Ready-to-eat (RTE) food does not undergo any treatment to ensure its safety before consumption, and therefore risk of foodborne disease must be considered if these pathogens are present in the food. To evaluate the prevalence of these pathogens in RTE food, 140 RTE fish product samples, 501 RTE meat product samples, 462 RTE dairy samples, and 123 RTE dishes and desserts, providing a total of 1,226 samples, were collected from retail stores and food industry and analyzed for the presence of L. monocytogenes. A total of 1,379 samples consisting of 187 RTE fish products and 569 RTE meat products, 484 RTE dairy products, and 139 RTE dishes and desserts were collected and analyzed for the presence of Salmonella. L. monocytogenes was isolated from 20% of frozen Atlantic bonito small pies, 7.9% of smoked salmon samples, 11.1% of the pork luncheon meat samples, 6.2% of frozen chicken croquettes, 16.9% of cured dried sausage samples, 12.5% of cooked ham samples, and 20% of cooked turkey breast samples. L. monocytogenes was also found to be present in 1.3% of fresh salty cheese samples and 15.1% of frozen cannelloni samples. Salmonella was isolated from 1.2% of smoked salmon samples, 1.5% of frozen chicken croquettes, 2% of cooked ham samples, and 11.1% of cured dried sausage samples. Overall, occurrence of these pathogens in RTE foods was similar to that previously reported in the literature.

2019 ◽  
Vol 6 (2) ◽  
Author(s):  
Bhakti Etza Setiani ◽  
Yoyok Budi Pramono ◽  
Lutfi Purwitasari

A study was conducted to review on pathogenic bacteria Listeria monocytogenes, the detection and the sequencing gene methods isolated from meat products, compare selected methods that detect the presence of Listeria monocytogenes in selected raw and processed meat products. Results indicate that Listeria monocytogenenes (originally named Bacterium monocytogenes) is a gram-positive, non-sporeforming, highly mobile, rod-type, and facultative anaerobic bacterium species. It can grow under temperatures between -1.5°C to 45°C and at pH range between 4.4 and 9.4, with the optimum pH of 7. Rapid methods (PCR based and VIDAS-LDUO®) detected Listeria monocytogenes faster than the conventional method. It was also gathered that Phenotypic identification and Genotypic identification are two types of confirmation test for Listeria monocytogenes. Listeria monocytogenenes can be found in raw meat and meat product because of environmental contamination, cross contamination or error process.


2021 ◽  
Vol 3 (2) ◽  
pp. 1-10
Author(s):  
Naeima M. H. Yousef ◽  
Doaa M. Abd El- Aziz ◽  
Martina A. Mansour

Foodborne pathogenic bacteria are causing diseases with a significant effect on human health and the economy. The four most common bacterial foodborne pathogens were isolated from different fermented meat products and characterized molecularly in the current study. A total of 20 random samples of fermented meat products, including Hotdog, pepperoni, salami, sausage, and luncheon (4 from each), were collected from different markets to be examined bacteriologically for detection of foodborne pathogenic bacteria. The samples were tested by culture for the presence of bacteria. PCR was used as a diagnostic tool for the proper identification of foodborne pathogenic bacteria. So, the pure isolates were identified and confirmed by PCR- based method using specific primers for each genus. The isolated pathogenic bacteria were identified as Escherichia coli 0157:H7, Listeria monocytogenes, Salmonella sp. and Staphylococcus aureus. Out of 20 samples, only one sample contains E. coli 0157:H7. Listeria monocytogenes and Salmonella spp. were isolated from two samples. At the same time, S. aureus was found in 6 samples, one of which was mecA positive. The results revealed the presence of foodborne pathogenic bacteria in fermented meat samples. So, to decrease the human hazard risk and a major public health threat associated with foodborne pathogenic bacteria and their toxins, a greater emphasis should be applied in control and prevention of contamination during processing and manipulation.


2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Paul Attien ◽  
Haziz Sina ◽  
Wardi Moussaoui ◽  
Gaëlle Zimmermann-Meisse ◽  
Thomas Dadié ◽  
...  

The aim of our study was to investigate the microbial quality of meat products and on some clinical samples in Abidjan focused onStaphylococcusgenus and the toxin production profile ofStaphylococcus aureus(S. aureus) isolated. Bacteria were collected from 240 samples of three meat products sold in Abidjan and 180 samples issued from clinical infections. The strains were identified by both microbiological and MALDI-TOF-MS methods. The susceptibility to antibiotics was determined by the disc diffusion method. The production of Panton-Valentine Leukocidin, LukE/D, and epidermolysins was screened using radial gel immunodiffusion. The production of staphylococcal enterotoxins and TSST-1 was screened by a Bio-Plex Assay. We observed that 96/240 of meat samples and 32/180 of clinical samples were contaminated byStaphylococcus. Eleven species were isolated from meats and 4 from clinical samples. Forty-twoS. aureusstrains were isolated from ours samples. Variability of resistance was observed for most of the tested antibiotics but none of the strains displays a resistance to imipenem and quinolones. We observed that 89% of clinicalS. aureuswere resistant to methicillin against 58% for those issued from meat products. AllS. aureusisolates issued from meat products produce epidermolysins whereas none of the clinical strains produced these toxins. The enterotoxins were variably produced by both clinical and meat product samples.


2006 ◽  
Vol 69 (1) ◽  
pp. 71-79 ◽  
Author(s):  
CHIA-MIN LIN ◽  
KAZUE TAKEUCHI ◽  
LEI ZHANG ◽  
CYNTHIA B. DOHM ◽  
JOSEPH D. MEYER ◽  
...  

Contamination of luncheon meats by Listeria monocytogenes has resulted in outbreaks of listeriosis and major product recalls. Listeriae can survive on processing equipment such as meat slicers which serve as a potential contamination source. This study was conducted to determine (i) the dynamics of cross-contamination of L. monocytogenes from a commercial slicer and associated equipment onto sliced meat products, (ii) the influence of sample size on the efficacy of the BAX-PCR and U.S. Department of Agriculture–Food Safety and Inspection Service enrichment culture assays to detect L. monocytogenes on deli meat, and (iii) the fate of L. monocytogenes on sliced deli meats of different types during refrigerated storage. Three types of deli meats, uncured oven-roasted turkey, salami, and bologna containing sodium diacetate and potassium lactate, were tested. A five-strain mixture of L. monocytogenes was inoculated at ca.103 CFU onto the blade of a commercial slicer. Five consecutive meat slices were packed per package, then vacuum sealed, stored at 4°C, and sampled at 1 and 30 days postslicing. Two sample sizes, 25 g and contents of the entire package of meat, were assayed. Total numbers of L. monocytogenes–positive samples, including the two sample sizes and two sampling times, were 80, 9, and 3 for turkey, salami, and bologna, respectively. A higher percentage of turkey meat samples were L. monocytogenes positive when contents of the entire package were assayed than when the 25-g sample was assayed (12.5 and 7.5%, respectively). Lower inoculum populations of ca. 101 or 102 CFU of L. monocytogenes on the slicer blade were used for an additional evaluation of oven-roasted turkey using two additional sampling times of 60 and 90 days postslicing. L. monocytogenes–positive samples were not detected until 60 days postslicing, and more positive samples were detected at 90 days than at 60 days postslicing. When BAX-PCR and enrichment culture assays were compared, 12, 8, and 2 L. monocytogenes–positive samples were detected by both the enrichment culture and BAX-PCR, BAX-PCR only, and enrichment culture only assays, respectively. The number of L. monocytogenes–positive samples and L. monocytogenes counts increased during storage of turkey meat but decreased for salami and bologna. Significantly more turkey samples were L. monocytogenes positive when the contents of the entire package were sampled than when 25 g was sampled. Our results indicate that L. monocytogenes can be transferred from a contaminated slicer onto meats and can survive or grow better on uncured oven-roasted turkey than on salami or bologna with preservatives. Higher L. monocytogenes cell numbers inoculated on the slicer blade resulted in more L. monocytogenes–positive sliced meat samples. In addition, the BAX-PCR assay was better than the enrichment culture assay at detecting L. monocytogenes on turkey meat (P < 0.05).


1998 ◽  
Vol 61 (6) ◽  
pp. 693-699 ◽  
Author(s):  
MARÍA G. CÓRDOBA ◽  
JUAN J. CÓRDOBA ◽  
RAFAEL JORDANO

Flamenquín is a traditional, prepared, frozen meat product from the south of Spain made with minced pork, chicken, and cooked ham. Since it is a prepared raw meat product some microbial hazards could be associated with the process of making it. Microbiological analyses have been performed throughout the various steps of processing over a 1-year period to evaluate microbial hazards in the commercial process. High levels of microorganisms were observed all through the processing of this product, the mincing and mixing steps being where major microbial contamination was observed. Pathogenic bacteria such as Staphylococcus aureus, Clostridium perfringens, Escherichia coli and Pseudomonas aeruginosa were detected during processing. Raw materials and food handlers were the principal sources of microbial contamination. A modification of processing to include a heating step after mincing and mixing and an improvement in hygiene practices could eliminate the microbial hazards. Both modifications should be noted for the implementation of a hazard analysis of critical control points (HACCP) program in commercial flamenquín processing.


2007 ◽  
Vol 70 (6) ◽  
pp. 1507-1512 ◽  
Author(s):  
L. LATORRE ◽  
A. PARISI ◽  
R. FRACCALVIERI ◽  
G. NORMANNO ◽  
M. C. NARDELLA LA PORTA ◽  
...  

Listeria monocytogenes is an important foodborne pathogen that causes gastrointestinal disorders, and, especially in immunocompromised people, serious extraintestinal diseases, such as septicemia and meningitis, as well as abortion in pregnant women. Many foods, from both plant and animal origin, have been involved in listeriosis outbreaks. This article reports the results of a 12-year survey (1993 through 2004) on the presence of L. monocytogenes in several kinds of food marketed in Italy. Of 5,788 analyzed samples, 121 (2.1%) were contaminated with L. monocytogenes. The highest prevalence was found in smoked salmon (10.6%) and in poultry meat samples (8.5%) and the lowest in red meat (0.3%). L. monocytogenes was not found in 154 samples of fresh seafood products. Fifty-two isolates were also serotyped by the agglutination method. The most common serotypes detected in the 52 strains tested were 1/2a (36.5%), followed by 1/2c (32.8%), 1/2b (13.5%), 4b (11.5%), 3a (3.8%), and 3b (1.9%). The results of the present study showed low levels of L. monocytogenes in the analyzed samples. A total of 61.5% of the 52 L. monocytogenes strains analyzed belonged to serotypes 1/2a, 1/2b, and 4b, namely the serovars that are most commonly involved in extraintestinal human listeriosis outbreaks. In the ready-to-eat samples, these three serotypes were 40.0% (1/2a), 17.1% (1/2b), and 14.3% (4b). This finding highlights the need to implement strict hygienic measures during the production, distribution, and sale of foods to reduce the risk of foodborne listeriosis in humans to an acceptable level.


2016 ◽  
Vol 34 (No. 6) ◽  
pp. 469-487 ◽  
Author(s):  
I. Khan ◽  
J. Khan ◽  
S. Miskeen ◽  
C.N. Tango ◽  
Y.S. Park ◽  
...  

Listeria monocytogenes is a Gram-positive facultative intracellular organism and causative agent of the severe foodborne infection listeriosis. L. monocytogenes is more likely to cause death rather than other pathogenic bacteria that cause foodborne illnesses. It is an ubiquitous organism that can be found in food industry equipment and premises. L. monocytogenes mainly occurs in the food production chain by cross-contamination, making this pathogen a major threat to the food industry. The pathogen may be found at low or moderate levels in the foodstuffs, but the levels involved in listeriosis outbreaks are relatively very high. The majority of isolates from food products belong to serotype 4b and 1/2a. The control of L. monocytogenes can be applied throughout the food chain. Pre- and post-harvest factors such as contact of pigs with pets and pest animals, large group size, hygiene practices, and treatment of manure affected the prevalence of L. monocytogenes in the food chain. Good farm-level practices could be utilised to reduce the occurrence of L. monocytogenes in the farm environment and possibly further in the food chain. Safety and low level of this pathogen in the food chain can be possible with good agricultural practices, good manufacturing practices, and high-quality raw materials. Therefore, food processing plants must be designed carefully with an emphasis on effective cleaning and disinfecting operations in the production line.


2017 ◽  
Vol 80 (6) ◽  
pp. 976-981 ◽  
Author(s):  
Siqi Wu ◽  
Hongxing Zhang ◽  
Huimin Zhou ◽  
Junhua Jin ◽  
Yuanhong Xie

ABSTRACT Plantaricin BM-1, a typical IIa bacteriocin, is produced by Lactobacillus plantarum BM-1, which can be isolated from a traditionally fermented Chinese meat product. This bacteriocin exhibits perfect thermal stability and broad inhibitory activity against certain foodborne pathogens. In this study, we investigated the effect of plantaricin BM-1 combined with physicochemical treatments (sodium nitrite, heat treatment, ultrahigh pressure technology) on the control of Listeria monocytogenes populations in cooked ham. According to our results, the addition of sodium nitrite (0.075 or 0.15 mg/mL) significantly inhibited the growth of L. monocytogenes in broth, plantaricin BM-1 combined with heat treatment reduced the viable counts of L. monocytogenes more than plantaricin BM-1 alone, and plantaricin BM-1 combined with sodium nitrite and heat treatment had the greatest antibacterial effect in broth. However, the addition of sodium nitrite or heat treatment alone did not inhibit the growth of L. monocytogenes in cooked ham. The combined application of 5,120 arbitrary units per gram (AU/g) plantaricin BM-1 and 0.075 mg/g sodium nitrite reduced L. monocytogenes significantly more effectively (by 1.97 log CFU/g) than application of 5,120 AU/g plantaricin alone. Plantaricin BM-1 application combined with sodium nitrite and heat treatment led to viable counts of L. monocytogenes below the level of detection for 49 days of storage. Moreover, in cooked ham treated with 5,120 AU/g plantaricin BM-1, 0.075 mg/g sodium nitrite, and ultrahigh pressure technology (400 MPa for 5 min), viable counts of L. monocytogenes were reduced by 5.79 log CFU/g compared with control samples at the end of storage. In conclusion, the combination of plantaricin BM-1 with physicochemical treatments had a synergistic inhibitory effect on L. monocytogenes in cooked ham.


2005 ◽  
Vol 68 (1) ◽  
pp. 164-167 ◽  
Author(s):  
CHRISTOPHER H. SOMMERS ◽  
GLENN BOYD

Listeria monocytogenes is a common postprocess contaminant on ready-to-eat foods including premade ready-to-eat sandwiches. One popular type of sandwich product is the tortilla wrap, which contains sliced luncheon meats and cheeses rolled within a flour tortilla. This study determined the radiation resistance of L. monocytogenes surface inoculated onto two types of commercially available wheat flour tortillas, processed cheese slices, and deli turkey meat. The D10-values for L. monocytogenes (the radiation dose required to inactivate 1 log of the pathogen) were 0.27 kGy when inoculated onto two flour tortilla types, 0.28 and 0.30 kGy when inoculated onto two types of sliced processed cheeses, and 0.58 and 0.65 kGy when inoculated onto two types of sliced deli turkey meat. When two types of tortilla wraps were assembled from the individual components and L. monocytogenes was inoculated into the interfaces between the individual components, the D10-values were 0.27 to 0.37 kGy in the tortilla and cheese interfaces, 0.33 to 0.41 kGy in the cheese and turkey interfaces, and 0.25 to 0.33 kGy in the turkey and tortilla interfaces. The ability of ionizing radiation to reduce pathogen levels on the complex tortilla, cheese, and luncheon meat product was limited by the higher radiation resistance of L. monocytogenes when inoculated onto the ready-to-eat turkey-meat component.


2002 ◽  
Vol 65 (2) ◽  
pp. 316-325 ◽  
Author(s):  
A. AMÉZQUITA ◽  
M. M. BRASHEARS

Forty-nine strains of lactic acid bacteria (LAB), isolated from commercially available ready-to-eat (RTE) meat products, were screened for their ability to inhibit the growth of Listeria monocytogenes at refrigeration (5°C) temperatures on agar spot tests. The three most inhibitory strains were identified as Pediococcus acidilactici, Lactobacillus casei, and Lactobacillus paracasei by 16S rDNA sequence analysis. Their antilisterial activity was quantified in associative cultures in deMan Rogosa Sharpe (MRS) broth at 5°C for 28 days, resulting in a pathogen reduction of 3.5 log10 cycles compared to its initial level. A combined culture of these strains was added to frankfurters and cooked ham coinoculated with L. monocytogenes, vacuum packaged, and stored at 5°C for 28 days. Bacteriostatic activity was observed in cooked ham, whereas bactericidal activity was observed in frankfurters. Numbers of L. monocytogenes were 4.2 to 4.7 log10 and 2.6 log10 cycles lower than controls in frankfurters and cooked ham, respectively, after the 28-day refrigerated storage. In all cases, numbers of LAB increased by only 1 log10 cycle. The strain identified as P. acidilactici was possibly a bacteriocin producer, whereas the antilisterial activity of the other two strains was due to the production of organic acids. There was no significant difference (P > 0.05) in the antilisterial activity detected in frankfurters whether the LAB strains were used individually or as combined cultures. Further studies over a 56-day period indicated no impact on the quality of the product. This method represents a potential antilisterial intervention in RTE meats, because it inhibited the growth of the pathogen at refrigeration temperatures without causing sensory changes.


Sign in / Sign up

Export Citation Format

Share Document