Prevalence of Salmonella Serovars, Listeria monocytogenes, and Escherichia coli O157:H7 in Mediterranean Ready-to-Eat Meat Products in Jordan

2014 ◽  
Vol 77 (1) ◽  
pp. 106-111 ◽  
Author(s):  
TAREQ M. OSAILI ◽  
ANAS A. AL-NABULSI ◽  
REYAD R. SHAKER ◽  
ZIAD W. JARADAT ◽  
MOHAMMAD TAHA ◽  
...  

The presence of Salmonella, Listeria monocytogenes, and Escherichia coli O157:H7 in ready-to-eat (RTE) meat products is considered a major concern for food control authorities worldwide. The aims of this study were to determine (i) the prevalence of Salmonella, L. monocytogenes, and E. coli O157:H7 in Mediterranean RTE chicken and beef (CB) products sold in Jordanian restaurants and (ii) the susceptibility of the isolates to antibiotics. A total of 1,028 samples of various types of RTE CB products (550 RTE chicken and 478 RTE beef products) were analyzed by methods described by the International Organization for Standardization followed by molecular confirmation of the isolates. The VITEK2 automated system was used for testing antibiotic susceptibility of the isolates. The overall prevalence of Salmonella serovars in RTE CB products was 0.5%, with 0.8 and 0.2% in RTE chicken and RTE beef, respectively. The overall prevalence of L. monocytogenes in RTE CB products was 2%, with 2.7 and 1.5% in RTE chicken and RTE beef products, respectively. E. coli O157:H7 was not isolated from any of the tested samples. Multidrug-resistant Salmonella and L. monocytogenes isolates were found. The majority of Salmonella isolates were sensitive to most of the tested antibiotics, and all of the isolates were resistant to more than one antibiotic. Similarly, more than 85% of L. monocytogenes isolates were sensitive to nine antibiotics, and the majority of L. monocytogenes isolates were resistant to fosfomycin and oxacillin.

2009 ◽  
Vol 72 (2) ◽  
pp. 251-259 ◽  
Author(s):  
JOHN R. RUBY ◽  
STEVEN C. INGHAM

The efficacy of adding presumptive Lactobacillus sakei (LS) strain 10-EGR-a, the most inhibitory from among 12 ground beef Lactobacillus isolates, to inhibit growth by Escherichia coli O157:H7 and multidrug-resistant (MDR) Salmonella (serovars Newport and Typhimurium) was evaluated in a beef-derived broth medium at 10°C and in fresh raw ground beef at 10 and 5°C. Pathogen inhibition was observed in the broth medium at both high (108:105 to 107:105) and low (106:105 to 105:105) LS:pathogen ratios. After 9 days at 10°C, in broth medium with high LS:pathogen ratios, growth of E. coli O157:H7 and MDR Salmonella was inhibited by an average of 2.6 and 3.2 log CFU/ml, respectively, whereas in broth medium with low LS:pathogen ratios, E. coli O157:H7 and MDR Salmonella growth was inhibited by an average of 2.8 and 1.8 log CFU/ml, respectively. However, in raw ground beef no significant inhibition was seen with LS:pathogen ratios of 105:102 to 105:103. Significant inhibition was seen at very high LS:pathogen ratios (106 to 107:102 to 103), but gross spoilage of the product occurred by day 6. Although presumptive LS 10-EGR-a can inhibit growth of E. coli O157:H7 and MDR Salmonella in a beef-derived broth medium, the inability to produce similar results in ground beef without deleteriously affecting the quality of the product is a limitation that needs further investigation.


2004 ◽  
Vol 67 (7) ◽  
pp. 1394-1402 ◽  
Author(s):  
R. Y. MURPHY ◽  
E. M. MARTIN ◽  
L. K. DUNCAN ◽  
B. L. BEARD ◽  
J. A. MARCY

At 55 to 70°C, thermal inactivation D-values for Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes were 19.05 to 0.038, 43.10 to 0.096, and 33.11 to 0.12 min, respectively, in ground turkey and 21.55 to 0.055, 37.04 to 0.066, and 36.90 to 0.063 min, respectively, in ground beef. The z-values were 5.73, 5.54, and 6.13°C, respectively, in ground turkey and 5.43, 5.74, and 6.01°C, respectively, in ground beef. In both ground turkey and beef, significant (P < 0.05) differences were found in the D-values between E. coli O157:H7 and Salmonella or between E. coli O157:H7 and L. monocytogenes. At 65 to 70°C, D-values for E. coli O157:H7, Salmonella, and L. monocytogenes were also significantly (P < 0.05) different between turkey and beef. The obtained D- and z-values were used in predicting process lethality of the pathogens in ground turkey and beef patties cooked in an air impingement oven and confirmed by inoculation studies for a 7-log (CFU/g) reduction of E. coli O157:H7, Salmonella, and L. monocytogenes.


Author(s):  
Noro Ravaonindrina ◽  
Iony Razanajatovo ◽  
Alexandra Bastaraud

Certains entéropathogènes majeurs sont associés aux produits carnés, notamment Salmonella spp. ou Escherichia coli pro­ducteur de shigatoxines (3), et ce, en lien avec les conditions d’hygiène rencontrées de l’abattage à l’étal (1). L’objectif a été d’évaluer (a) le niveau des indicateurs d’hygiène comme E. coli, (b) la prévalence de Salmonella spp., de Campylobacter ther­motolérants, de Listeria monocytogenes, d’Yersinia enterocolitica et d’E. coli O157:H7 dans les viandes commercialisées dans la communauté urbaine d’Antananarivo, et (c) la sensibilité aux antibiotiques des isolats.Au total 137 échantillons, incluant de la viande de zébu hachée (n = 52) ou non (n = 48), et de la viande de porc hachée (n = 10) ou non (n = 27) ont été collectés dans les grandes sur­faces (24 p. 100) et sur les marchés d’Antananarivo (76 p. 100) d’avril à novembre 2014. Des méthodes conventionnelles ISO (International Organization for Standardization) et validées (Vidas technologie Biomérieux) ont été mises en oeuvre, ainsi que la confirmation des isolats par spectrométrie de masse (Maldi-TOFF, Bruker) ou par biologie moléculaire pour E. coli O157H7 (2). Le profil d’antibio-résistance des isolats a été déterminé sur Adagio Automated System (Biorad).Moins de 2 p. 100 des échantillons respectaient les critères microbiologiques d’hygiène du Règlement européen CE n° 2073/2005 (respectivement 70 et 90 p. 100 de non-conformité pour les micro-organismes aérobies et pour E. coli). Au total 111 échantillons (81 p. 100) étaient porteurs au moins d’un micro-organisme potentiellement pathogène ; 74 S. enterica subsp. enterica ont été isolées avec 33 sérovars identifiés dont deux prédominants, Budapest (21 p. 100) et Muenchen (21 p. 100) ; 48 E. coli O157:H7 ont été isolés principalement dans la filière bovine (63 p. 100) ; L. monocytogenes et Campylobacter thermo­tolérants ont été détectés respectivement dans 3 et 2 p. 100 des échantillons, et Y. enterocolitica n’a pas été détectée (tableau I).Les isolats de Salmonella ont été sensibles aux antibiotiques tes­tés, hormis une S. enterica serovar Bahrenfeld qui a résisté aux fluoroquinolones, notamment à la ciprofloxacine. Par ailleurs, 35 souches d’E.coli O157:H7 testées présentaient un phénotype sauvage et huit isolats avaient un phénotype d’hyperproduction de céphalosporinases (tableau II).Les conditions d’hygiène rencontrées sur l’ensemble de la filière bovine et porcine sont nettement insuffisantes et contribuent à la propagation de pathogènes entériques, comme Salmonella enterica et le pathovar Escherichia coli O157:H7. Des phéno­types multirésistants aux antibiotiques émergent, représentant un facteur de risque pour la santé des consommateurs. Par conséquence, nous élargirons le champ des investigations aux abattoirs et aux élevages pour une caractérisation génotypique des isolats qui permettra de rechercher les sources et les moda­lités potentielles de contamination.


2006 ◽  
Vol 69 (5) ◽  
pp. 1080-1086 ◽  
Author(s):  
T. OSAILI ◽  
C. L. GRIFFIS ◽  
E. M. MARTIN ◽  
B. L. BEARD ◽  
A. KEENER ◽  
...  

Thermal inactivation studies were used to determine the D- and z-values of Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes in ready-to-eat chicken-fried beef patties. Inoculated meat was packaged in sterile bags, which were immersed in a circulated water bath and held at 55, 57.5, 60, 62.5, 65, 67.5, and 70°C for different lengths of time. D- and z-values were determined with a linear regression model. Average D-values at temperatures 55 to 70°C were 27.62 to 0.04 min for E. coli O157:H7, 67.68 to 0.22 min for Salmonella, and 81.37 to 0.31 min for L. monocytogenes. The z-values were 5.2°C for E. coli O157:H7, 6.0°C for Salmonella, and 6.1°C for L. monocytogenes. The results of this study can be used by food processors to validate their processes and help eliminate pathogenic bacteria associated with chicken-fried beef products.


2018 ◽  
Vol 19 (0) ◽  
Author(s):  
Priscila Alves Dias ◽  
Daiani Teixeira Silva ◽  
Cláudio Dias Timm

Resumo Kefir é o produto da fermentação do leite pelos grãos de kefir. Esses grãos contêm uma mistura simbiótica de bactérias e leveduras imersas em uma matriz composta de polissacarídeos e proteínas. Muitos benefícios à saúde humana têm sido atribuídos ao kefir, incluindo atividade antimicrobiana contra bactérias Gram positivas e Gram negativas. A atividade antimicrobiana de 60 microrganismos isolados de grãos de kefir, frente à Escherichia coli O157:H7, Salmonella enterica subsp. enterica sorotipos Typhimurium e Enteritidis, Staphylococcus aureus e Listeria monocytogenes, foi estudada através do teste do antagonismo. A ação antimicrobiana dos sobrenadantes das bactérias ácido-lácticas que apresentaram atividade no teste do antagonismo foi testada. O experimento foi repetido usando sobrenadantes com pH neutralizado. Salmonella Typhimurium e Enteritidis sobreviveram por 24 horas no kefir em fermentação. E. coli O157:H7, S. aureus e L. monocytogenes foram recuperados até 72 horas após o início da fermentação. Todos os isolados apresentaram atividade antimicrobiana contra pelo menos um dos patógenos usados no teste do antagonismo. Sobrenadantes de 25 isolados apresentaram atividade inibitória e três mantiveram essa atividade com pH neutralizado. As bactérias patogênicas estudadas sobreviveram por tempo superior àquele normalmente utilizado para a fermentação do kefir artesanal, o que caracteriza perigo em potencial para o consumidor quando a matéria-prima não apresentar segurança sanitária. Lactobacillus isolados de grãos de kefir apresentam atividade antimicrobiana contra cepas de E. coli O157:H7, Salmonella sorotipos Typhimurium e Enteritidis, S. aureus e L. monocytogenes além daquela exercida pela diminuição do pH.


2005 ◽  
Vol 68 (12) ◽  
pp. 2559-2566 ◽  
Author(s):  
SYLVIA GAYSINSKY ◽  
P. MICHAEL DAVIDSON ◽  
BARRY D. BRUCE ◽  
JOCHEN WEISS

Growth inhibition of four strains of Escherichia coli O157:H7 (H1730, F4546, 932, and E0019) and Listeria monocytogenes (Scott A, 101, 108, and 310) by essential oil components (carvacrol and eugenol) solubilized in nonionic surfactant micelles (Surfynol 465 and 485W) was investigated. Concentrations of encapsulated essential oil components ranged from 0.02 to 1.25% depending on compound, surfactant type, and surfactant concentration (0.5 to 5%). Eugenol encapsulated in Surfynol 485W micelles was most efficient in inhibiting growth of the pathogens; 1% Surfynol 485W and 0.15% eugenol was sufficient to inhibit growth of all strains of E. coli O157:H7 and three of four strains of L. monocytogenes (Scott A, 310, and 108). The fourth strain, L. monocytogenes 101, was inhibited by 2.5% Surfynol and 0.225% eugenol. One percent Surfynol 485W in combination with 0.025% carvacrol was effective in inhibiting three of four strains of E. coli O157:H7. Strain H1730 was the most resistant strain, requiring 0.3% carvacrol and 5% surfactant for complete inhibition. Growth inhibition of L. monocytogenes by combinations of carvacrol and Surfynol 465 ranged between 0.15 and 0.35% and 1 and 3.75%, respectively. Generally, the antimicrobial activity of Surfynol 465 in combination with eugenol was higher than that for the combination with carvacrol. The potent activity was attributed to increased solubility of essential oil components in the aqueous phase due to the presence of surfactants and improved interactions of antimicrobials with microorganisms.


2002 ◽  
Vol 65 (8) ◽  
pp. 1215-1220 ◽  
Author(s):  
CHIA-MIN LIN ◽  
SARAH S. MOON ◽  
MICHAEL P. DOYLE ◽  
KAY H. McWATTERS

Iceberg lettuce is a major component in vegetable salad and has been associated with many outbreaks of foodborne illnesses. In this study, several combinations of lactic acid and hydrogen peroxide were tested to obtain effective antibacterial activity without adverse effects on sensory characteristics. A five-strain mixture of Escherichia coli O157:H7, Salmonella enterica serotype Enteritidis, and Listeria monocytogenes was inoculated separately onto fresh-cut lettuce leaves, which were later treated with 1.5% lactic acid plus 1.5% hydrogen peroxide (H2O2) at 40°C for 15 min, 1.5% lactic acid plus 2% H2O2 at 22°C for 5 min, and 2% H2O2 at 50°C for 60 or 90 s. Control lettuce leaves were treated with deionized water under the same conditions. A 4-log reduction was obtained for lettuce treated with the combinations of lactic acid and H2O2 for E. coli O157:H7 and Salmonella Enteritidis, and a 3-log reduction was obtained for L. monocytogenes. However, the sensory characteristics of lettuce were compromised by these treatments. The treatment of lettuce leaves with 2% H2O2 at 50°C was effective not only in reducing pathogenic bacteria but also in maintaining good sensory quality for up to 15 days. A ≤4-log reduction of E. coli O157:H7 and Salmonella Enteritidis was achieved with the 2% H2O2 treatment, whereas a 3-log reduction of L. monocytogenes was obtained. There was no significant difference (P > 0.05) between pathogen population reductions obtained with 2% H2O2 with 60- and 90-s exposure times. Hydrogen peroxide residue was undetectable (the minimum level of sensitivity was 2 ppm) on lettuce surfaces after the treated lettuce was rinsed with cold water and centrifuged with a salad spinner. Hence, the treatment of lettuce with 2% H2O2 at 50°C for 60 s is effective in initially reducing substantial populations of foodborne pathogens and maintaining high product quality.


2004 ◽  
Vol 132 (2) ◽  
pp. 283-289 ◽  
Author(s):  
D. M. MacDONALD ◽  
M. FYFE ◽  
A. PACCAGNELLA ◽  
A. TRINIDAD ◽  
K. LOUIE ◽  
...  

An outbreak of E. coli O157:H7 infections was identified in November 1999 with a fivefold increase in the occurrence of laboratory-confirmed cases of E. coli O157:H7 infection. A matched case-control study was conducted. Samples of food from cases and from retailers were analysed for the presence of E. coli O157:H7. A total of 143 cases were identified over a 12-week period with the same pulsed-field gel electrophoresis (PFGE) pattern. The case-control study found that Company A salami was significantly associated with illness (Mantel–Haenszel matched odds ratio 10·0, 95% CI 1·4–434, P=0·01). Company A salami tested positive for E. coli O157:H7 and isolates had the same PFGE pattern as case isolates. An immediate voluntary national recall of Company A dry fermented meat products took place. Findings from the investigation of this outbreak suggest that the hold-and-test option may not be adequate to prevent shiga-toxigenic Escherichia coli (STEC) infection in salami consumers.


1997 ◽  
Vol 60 (5) ◽  
pp. 471-475 ◽  
Author(s):  
ALICIA ORTA-RAMIREZ ◽  
JAMES F. PRICE ◽  
YIH-CHIH HSU ◽  
GIRIDARAN J. VEERAMUTHU ◽  
JAMIE S. CHERRY-MERRITT ◽  
...  

The USDA has established processing schedules for beef products based on the destruction of pathogens. Several enzymes have been suggested as potential indicators of heat processing. However, no relationship between the inactivation rates of these enzymes and those of pathogenic microorganisms has been determined. Our objective was to compare the thermal inactivation of Escherichia coli O157:H7 and Salmonella senftenberg to those of endogenous muscle proteins. Inoculated and noninoculated ground beef samples were heated at four temperatures for predetermined intervals of time in thermal-death-time studies. Bacterial counts were determined and enzymes were assayed for residual activity. The D values for E. coli O157:H7 were 46.10, 6.44, 0.43, and 0.12 min at 53, 58, 63, and 68°C, respectively, with a z value of 5.60°C. The D values for S. senftenberg were 53.00, 15.17, 2.08, and 0.22 min at 53, 58, 63, and 68°C, respectively, with a z value of 6.24°C. Apparent D values at 53, 58, 63, and 68°C were 352.93, 26.31, 5.56, and 3.33 min for acid phosphatase; 6968.64, 543.48, 19.61, and 1.40 min for lactate dehydrogenase; and 3870.97, 2678.59, 769.23, and 42.92 min for peroxidase; with z values of 7.41,3.99, and 7.80°C, respectively. Apparent D values at 53, 58, 63, and 66°C were 325.03, 60.07, 3.07, and 1.34 min for phosphoglycerate mutase; 606.72, 89.86, 4.40, and 1.28 min for glyceraldehyde-3-phosphate dehydrogenase; and 153.06, 20.13, 2.25, and 0.74 min for triose phosphate isomerase; with z values of 5.18, 4.71, and 5.56°C, respectively. The temperature dependence of triose phosphate isomerase was similar to those of both E. coli O157 :H7 and S. senftenberg, suggesting that this enzyme could be used as an endogenous time-temperature indicator in beef products.


2007 ◽  
Vol 70 (10) ◽  
pp. 2230-2234 ◽  
Author(s):  
T. W. THOMPSON ◽  
T. P. STEPHENS ◽  
G. H. LONERAGAN ◽  
M. F. MILLER ◽  
M. M. BRASHEARS

Rapid enzyme-linked immunosorbent assays (ELISAs) are approved for detection of Escherichia coli O157 in beef products. However, these kits have also been used in the industry to detect this pathogen on hides or in feces of cattle, although this use has not been validated. The objective of this study was to compare commercially available ELISAs (E. coli Now, Reveal, and VIP) with immunomagnetic separation along with selective media to detect E. coli O157 on hides, in feces, and in medium- and low-level-inoculated ground beef and carcasses (simulated by using briskets) samples. Naturally infected hide and fecal samples were subjected to both the immunomagnetic separation method and ELISAs for the detection of E. coli O157. Additionally, E. coli O157 inoculated and noninoculated ground beef and beef briskets were used to simulate meat and carcass samples. When comparing the detection results from the ELISAs (E. coli Now, Reveal, and VIP) to the immunomagnetic separation method, poor agreement was observed for fecal samples (kappa = 0.10, 0.02, and 0.03 for E. coli Now, Reveal, and VIP, respectively), and fair-to-moderate agreement was observed for hide samples (kappa = 0.30, 0.51, and 0.29 for E. coli Now, Reveal, and VIP, respectively). However, there was near-perfect agreement between the immunomagnetic separation method and ELISAs for ground beef (kappa = 1, 1, and 0.80 for E. coli Now, Reveal, and VIP, respectively) and brisket (kappa = 1, 1, and 1 for E. coli Now, Reveal, and VIP, respectively) samples. Assuming immunomagnetic separation is the best available method, these data suggest that the ELISAs are not useful in detecting E. coli O157 from hide or fecal samples. However, when ELISAs are used on ground beef and beef brisket samples they can be used with a high degree of confidence.


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