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Paula Teixeira - One of the best experts on this subject based on the ideXlab platform.

  • diverse geno and phenotypes of persistent listeria monocytogenes isolates from Fermented Meat sausage production facilities in portugal
    Applied and Environmental Microbiology, 2011
    Co-Authors: Joana Barbosa, Vânia Ferreira, Paula Teixeira, Matthew J Stasiewicz, Kitiya Vongkamjan, Moreno A Switt, Tim Hogg, Paul Gibbs, Martin Wiedmann
    Abstract:

    The persistence of Listeria monocytogenes in food-associated environments represents a key factor in transmission of this pathogen. To identify persistent and transient strains associated with production of Fermented Meat sausages in northern Portugal, 1,723 L. monocytogenes isolates from raw material and finished products from 11 processors were initially characterized by random amplification of polymorphic DNA (RAPD), PCR-based molecular serotyping, and epidemic clone characterization, as well as cadmium, arsenic, and tetracycline resistance typing. Pulsed-field gel electrophoresis (PFGE) typing of 240 representative isolates provided evidence for persistence of L. monocytogenes for periods of time ranging from 10 to 32 months for all seven processors for which isolates from different production dates were available. Among 50 L. monocytogenes isolates that included one representative for each PFGE pattern obtained from a given sample, 12 isolates showed reduced invasion efficiency in Caco-2 cells, including 8 isolates with premature stop codons in inlA. Among 41 isolates representing sporadic and persistent PFGE types, 22 isolates represented lysogens. Neither strains with reduced invasion nor lysogens were overrepresented among persistent isolates. While the susceptibility of isolates to lysogenic phages also did not correlate with persistence, it appeared to be associated with molecular serotype. Our data show the following. (i) RAPD may not be suitable for analysis of large sets of L. monocytogenes isolates. (ii) While a large diversity of L. monocytogenes subtypes is found in Portuguese Fermented Meat sausages, persistence of L. monocytogenes in this food chain is common. (iii) Persistent L. monocytogenes strains are diverse and do not appear to be characterized by unique genetic or phenotypic characteristics.

  • virulence factors among enterococci isolated from traditional Fermented Meat products produced in the north of portugal
    Food Control, 2010
    Co-Authors: Joana Barbosa, Paul A Gibbs, Paula Teixeira
    Abstract:

    Abstract The aim of this work was to characterize Enterococcus spp. isolated from Alheira, Chourica de Vinhais and Salpicao de Vinhais, Fermented Meat products produced in the North of Portugal, concerning their potential pathogenicity. One hundred and eighty two isolates (76 identified as Enterococcus faecalis, 44 as Enterococcus faecium, 1 as Enterococcus casseliflavus and 61 as Enterococcus spp.) were studied. Twenty six percent of isolates were gelatinase producers. None of the isolates produced lipase nor DNase activities. Hemolytic activity using sheep and human blood from two types (A and O) was assessed. One isolate was β-hemolytic in human blood. Results obtained in sheep blood were quite different from those obtained in human blood. Biofilm production in batch and in fed-batch mode was evaluated. In batch mode, only 28.0% and 3.9% of isolates were classified as moderate and strong biofilm producers, respectively, and in fed-batch mode, 35.7% and 63.2% of isolates were classified as moderate and strong biofilm producers, respectively. The presence of 13 virulence genes (efaAfs, efaAfm, esp, agg, cylM, cylB, cylA, cylLL cylLs and gelE) were investigated by PCR. The majority of enterococcal isolates showed the presence of one or more virulence factors, the most frequent genotype being efaAfs+ gelE+ agg+ (41.5%). E. faecalis isolates harbored multiple virulence traits, while E. faecium isolates were generally free of virulence determinants. Phenotypic and genotypic evidence of potential virulence factors were identified in Enterococcus spp. isolates, which is a reason of concern.

  • antibiotic susceptibility of enterococci isolated from traditional Fermented Meat products
    Food Microbiology, 2009
    Co-Authors: Joana Barbosa, Vânia Ferreira, Paula Teixeira
    Abstract:

    Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chourica de Vinhais and Salpicao de Vinhais, Fermented Meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus faecalis, 44 as Enterococcus faecium, one as Enterococcus casseliflavus and 61 as Enteroccocus spp. In order to encompass several of the known chemical and functional classes of antibiotics, resistance to ampicillin, penicillin G, ciprofloxacin, chloramphenicol, erythromycin, nitrofurantoin, rifampicin, tetracycline and vancomycin was evaluated. All the isolates were sensitive to antibiotics of clinical importance, such as penicillins and vancomycin. Some differences in Minimal Inhibitory Concentrations (MICs) of antibiotics, could be associated with the enterococcal species.

  • chemical and microbiological characterization of alheira a typical portuguese Fermented sausage with particular reference to factors relating to food safety
    Meat Science, 2006
    Co-Authors: Vânia Ferreira, Joana Barbosa, Tim Hogg, Paul Gibbs, Sandra Vendeiro, Ana Mota, Fatima Silva, Maria Joao Monteiro, Paula Teixeira
    Abstract:

    Abstract Alheiras are traditional smoked naturally Fermented Meat sausages produced in the north of Portugal. They have not previously been characterized as to their chemical and microbiological status. pH and salt levels are insufficient to assure microbiological safety, there is ample opportunity for post-cooking contamination; the products require chill storage and cooking before consumption. Heavy metals and biogenic amines were, in general, within accepted limits for Meat products. Lactic acid bacteria comprised the major microflora (ca. 7–8 log cfu/g) with substantial counts of micrococci and enterococci (up to 7 log cfu/g). Escherichia coli, Staphylococcus aureus and Listeria spp. were detected in several samples.

Svetoslav Dimitrov Todorov - One of the best experts on this subject based on the ideXlab platform.

  • Bacteriocinogenic LAB Strains for Fermented Meat Preservation: Perspectives, Challenges, and Limitations
    Probiotics and Antimicrobial Proteins, 2017
    Co-Authors: Lorenzo Favaro, Svetoslav Dimitrov Todorov
    Abstract:

    Over the last decades, much research has focused on lactic acid bacteria (LAB) bacteriocins because of their potential as biopreservatives and their action against the growth of spoilage microbes. Meat and Fermented Meat products are prone to microbial contamination, causing health risks, as well as economic losses in the Meat industry. The use of bacteriocin-producing LAB starter or protective cultures is suitable for Fermented Meats. However, although bacteriocins can be produced during Meat processing, their levels are usually much lower than those achieved during in vitro fermentations under optimal environmental conditions. Thus, the direct addition of a bacteriocin food additive would be desirable. Moreover, safety and technological characteristics of the bacteriocinogenic LAB must be considered before their widespread applications. This review describes the perspectives and challenges toward the complete disclosure of new bacteriocins as effective preservatives in the production of safe and “healthy” Fermented Meat products.

  • technology and safety assessment for lactic acid bacteria isolated from traditional bulgarian Fermented Meat product lukanka
    Brazilian Journal of Microbiology, 2017
    Co-Authors: Svetoslav Dimitrov Todorov, Saso Stojanovski, Ilia Iliev, Penka Moncheva, Luis Augusto Nero, Iskra Ivanova
    Abstract:

    The present work discusses the technological and new selection criteria that should be included for selecting lactic acid bacteria for production of Fermented Meat. Lactic acid bacteria isolated from Bulgarian traditional Fermented “lulanka” salami was studied regarding some positive technological parameters (growth at different temperature, pH, and proteolytic activity). The presence of genes related to the virulence factors, production of biogenic amines, and vancomycin resistance were presented in low frequency in the studied lactic acid bacteria. On the other hand, production of antimicrobial peptides and high spread of bacteriocin genes were broadly presented. Very strong activity against L. monocytogenes was detected in some of the studied lactic acid bacteria. In addition, the studied strains did not present any antimicrobial activity against tested closely related bacteria such as Lactobacillus spp., Lactococcus spp., Enterococcus spp. or Pediococcus spp. To our knowledge this is the first study on the safety and antimicrobial properties of lactic acid bacteria isolated from Bulgarian lukanka obtained by spontaneous fermentation.

  • in vitro study of beneficial properties and safety of lactic acid bacteria isolated from portuguese Fermented Meat products
    Beneficial Microbes, 2014
    Co-Authors: Svetoslav Dimitrov Todorov, Bernadette Dora Gombossy De Melo Franco, I J Wiid
    Abstract:

    Many lactic acid bacteria produce bacteriocins with a rather broad spectrum of inhibition, which could offer potential applications in food preservation. Bacteriocin production by starter cultures may bring advantage to these strains in competitive interactions with pathogenic bacteria from the food matrix. The objective of this study was to determine the safety of beneficial strains (Lactobacillus plantarum ST202Ch and ST216Ch, Enterococcus faecium ST211Ch, and Lactobacillus sakei ST22Ch, ST153Ch and ST154Ch) previously isolated from Fermented Meat products and characterised as bacteriocin producers. Auto-aggregation was strain-specific, and values of 28.97, 27.86 and 28.56% were recorded for L. sakei ST22Ch, ST153Ch and ST154Ch, respectively, 16.95 and 14.58% for L. plantarum ST202Ch and ST216Ch, respectively, and 12.77% for E. faecium ST211Ch. Various degrees of co-aggregation between 28.85 and 44.76% for Listeria monocytogenes 211 and 409, and between 23.60 to 34.96% for E. faecium ATCC 19443 were obs...

  • in vitro study of beneficial properties and safety of lactic acid bacteria isolated from portuguese Fermented Meat products
    Beneficial Microbes, 2014
    Co-Authors: Svetoslav Dimitrov Todorov, Bernadette Dora Gombossy De Melo Franco, I J Wiid
    Abstract:

    Many lactic acid bacteria produce bacteriocins with a rather broad spectrum of inhibition, which could offer potential applications in food preservation. Bacteriocin production by starter cultures may bring advantage to these strains in competitive interactions with pathogenic bacteria from the food matrix. The objective of this study was to determine the safety of beneficial strains (Lactobacillus plantarum ST202Ch and ST216Ch, Enterococcus faecium ST211Ch, and Lactobacillus sakei ST22Ch, ST153Ch and ST154Ch) previously isolated from Fermented Meat products and characterised as bacteriocin producers. Auto-aggregation was strain-specific, and values of 28.97, 27.86 and 28.56% were recorded for L. sakei ST22Ch, ST153Ch and ST154Ch, respectively, 16.95 and 14.58% for L. plantarum ST202Ch and ST216Ch, respectively, and 12.77% for E. faecium ST211Ch. Various degrees of co-aggregation between 28.85 and 44.76% for Listeria monocytogenes 211 and 409, and between 23.60 to 34.96% for E. faecium ATCC 19443 were observed. According to the results of the diffusion method, the studied strains demonstrated susceptibility to penicillin G, ampicillin, amoxicillin, amoxicillin/clavulonic acid, imipenem, linezolid, and tetracycline. In addition, the susceptibility of the six strains to various non-antibiotic commercial drugs was examined. Production of β-galactosidase by L. sakei ST22Ch, ST153Ch and ST154Ch, L. plantarum ST202Ch and ST216Ch, and E. faecium ST211Ch was confirmed by employing sterile filter paper discs impregnated with o-nitrophenyl-β-D-galactopyranose. A statistically significant (P<0.001) inhibition of Mycobacterium tuberculosis growth by bacteriocins produced by L. plantarum ST202Ch (38.3%) and ST216Ch (48.6%), L. sakei ST153Ch (16.2%) and ST154Ch (16.1%), and E. faecium ST211Ch (21.7%) was observed. As determined by the polymerase chain reaction, the tested strains showed a low virulence gene profile.

Joana Barbosa - One of the best experts on this subject based on the ideXlab platform.

  • diverse geno and phenotypes of persistent listeria monocytogenes isolates from Fermented Meat sausage production facilities in portugal
    Applied and Environmental Microbiology, 2011
    Co-Authors: Joana Barbosa, Vânia Ferreira, Paula Teixeira, Matthew J Stasiewicz, Kitiya Vongkamjan, Moreno A Switt, Tim Hogg, Paul Gibbs, Martin Wiedmann
    Abstract:

    The persistence of Listeria monocytogenes in food-associated environments represents a key factor in transmission of this pathogen. To identify persistent and transient strains associated with production of Fermented Meat sausages in northern Portugal, 1,723 L. monocytogenes isolates from raw material and finished products from 11 processors were initially characterized by random amplification of polymorphic DNA (RAPD), PCR-based molecular serotyping, and epidemic clone characterization, as well as cadmium, arsenic, and tetracycline resistance typing. Pulsed-field gel electrophoresis (PFGE) typing of 240 representative isolates provided evidence for persistence of L. monocytogenes for periods of time ranging from 10 to 32 months for all seven processors for which isolates from different production dates were available. Among 50 L. monocytogenes isolates that included one representative for each PFGE pattern obtained from a given sample, 12 isolates showed reduced invasion efficiency in Caco-2 cells, including 8 isolates with premature stop codons in inlA. Among 41 isolates representing sporadic and persistent PFGE types, 22 isolates represented lysogens. Neither strains with reduced invasion nor lysogens were overrepresented among persistent isolates. While the susceptibility of isolates to lysogenic phages also did not correlate with persistence, it appeared to be associated with molecular serotype. Our data show the following. (i) RAPD may not be suitable for analysis of large sets of L. monocytogenes isolates. (ii) While a large diversity of L. monocytogenes subtypes is found in Portuguese Fermented Meat sausages, persistence of L. monocytogenes in this food chain is common. (iii) Persistent L. monocytogenes strains are diverse and do not appear to be characterized by unique genetic or phenotypic characteristics.

  • virulence factors among enterococci isolated from traditional Fermented Meat products produced in the north of portugal
    Food Control, 2010
    Co-Authors: Joana Barbosa, Paul A Gibbs, Paula Teixeira
    Abstract:

    Abstract The aim of this work was to characterize Enterococcus spp. isolated from Alheira, Chourica de Vinhais and Salpicao de Vinhais, Fermented Meat products produced in the North of Portugal, concerning their potential pathogenicity. One hundred and eighty two isolates (76 identified as Enterococcus faecalis, 44 as Enterococcus faecium, 1 as Enterococcus casseliflavus and 61 as Enterococcus spp.) were studied. Twenty six percent of isolates were gelatinase producers. None of the isolates produced lipase nor DNase activities. Hemolytic activity using sheep and human blood from two types (A and O) was assessed. One isolate was β-hemolytic in human blood. Results obtained in sheep blood were quite different from those obtained in human blood. Biofilm production in batch and in fed-batch mode was evaluated. In batch mode, only 28.0% and 3.9% of isolates were classified as moderate and strong biofilm producers, respectively, and in fed-batch mode, 35.7% and 63.2% of isolates were classified as moderate and strong biofilm producers, respectively. The presence of 13 virulence genes (efaAfs, efaAfm, esp, agg, cylM, cylB, cylA, cylLL cylLs and gelE) were investigated by PCR. The majority of enterococcal isolates showed the presence of one or more virulence factors, the most frequent genotype being efaAfs+ gelE+ agg+ (41.5%). E. faecalis isolates harbored multiple virulence traits, while E. faecium isolates were generally free of virulence determinants. Phenotypic and genotypic evidence of potential virulence factors were identified in Enterococcus spp. isolates, which is a reason of concern.

  • antibiotic susceptibility of enterococci isolated from traditional Fermented Meat products
    Food Microbiology, 2009
    Co-Authors: Joana Barbosa, Vânia Ferreira, Paula Teixeira
    Abstract:

    Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chourica de Vinhais and Salpicao de Vinhais, Fermented Meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus faecalis, 44 as Enterococcus faecium, one as Enterococcus casseliflavus and 61 as Enteroccocus spp. In order to encompass several of the known chemical and functional classes of antibiotics, resistance to ampicillin, penicillin G, ciprofloxacin, chloramphenicol, erythromycin, nitrofurantoin, rifampicin, tetracycline and vancomycin was evaluated. All the isolates were sensitive to antibiotics of clinical importance, such as penicillins and vancomycin. Some differences in Minimal Inhibitory Concentrations (MICs) of antibiotics, could be associated with the enterococcal species.

  • chemical and microbiological characterization of alheira a typical portuguese Fermented sausage with particular reference to factors relating to food safety
    Meat Science, 2006
    Co-Authors: Vânia Ferreira, Joana Barbosa, Tim Hogg, Paul Gibbs, Sandra Vendeiro, Ana Mota, Fatima Silva, Maria Joao Monteiro, Paula Teixeira
    Abstract:

    Abstract Alheiras are traditional smoked naturally Fermented Meat sausages produced in the north of Portugal. They have not previously been characterized as to their chemical and microbiological status. pH and salt levels are insufficient to assure microbiological safety, there is ample opportunity for post-cooking contamination; the products require chill storage and cooking before consumption. Heavy metals and biogenic amines were, in general, within accepted limits for Meat products. Lactic acid bacteria comprised the major microflora (ca. 7–8 log cfu/g) with substantial counts of micrococci and enterococci (up to 7 log cfu/g). Escherichia coli, Staphylococcus aureus and Listeria spp. were detected in several samples.

Leo Meile - One of the best experts on this subject based on the ideXlab platform.

  • complete genome sequences of lactobacillus curvatus kg6 l curvatus mrs6 and lactobacillus sakei fam18311 isolated from Fermented Meat products
    Genome Announcements, 2017
    Co-Authors: Christoph Jans, Sandra Lagler, Leo Meile, Christophe Lacroix, Mark J A Stevens
    Abstract:

    ABSTRACT The genomes of Lactobacillus curvatus KG6, L. curvatus MRS6, and Lactobacillus sakei FAM18311 were sequenced and assembled using PacBio single-molecule real-time (SMRT) technology. The strains were isolated from Swiss Fermented Meat products. Circular chromosomes were of 1.98 Mbp (KG6), 2.11 Mbp (MRS6), and 1.95 Mbp (FAM18311), with a G+C content of 41.3 to 42.0%.

  • prevalence of antibiotic resistance in coagulase negative staphylococci from spontaneously Fermented Meat products and safety assessment for new starters
    International Journal of Food Microbiology, 2012
    Co-Authors: Esther Marty, Chantal Bodenmann, Jasmin Buchs, Ruedi Hadorn, Elisabeth Eugstermeier, Christophe Lacroix, Leo Meile
    Abstract:

    Abstract To provide new Meat starter strains lacking antibiotic (AB) resistances, we explored the AB susceptibility in 116 coagulase-negative Staphylococcus (CNS) isolates from traditionally Fermented sausages (n = 40) manufactured with Meat from conventional animal breeding, and from Meat products (n = 76) made from Meat of animals raised in natural habitats under low- or no-antibiotic pressure. Less than 50% of these CNS isolates showed phenotypic resistances to at least one antibiotic (AB) by using microdilution assay. Resistances to penicillins and tetracycline were most often observed and could be traced back to blaZ and tet(K) genes. Prevalence of AB resistances was species-dependent and mainly found in isolates of Staphylococcus warneri (78%), Staphylococcus capitis (75%) and Staphylococcus epidermidis (67%), but only sporadically detected in Staphylococcus carnosus (27%) and Staphylococcus equorum (18%). AB resistances were more often observed in S. xylosus isolates originating from natural habitats compared to traditionally Fermented sausages made from conventional Meat. A selection of 101 isolates belonging to S. xylosus (n = 63), S. carnosus (n = 21) and S. equorum (n = 17) were subsequently grouped by pulsed-field gel electrophoresis (PFGE) into strain clusters. No S. carnosus and only five S. xylosus strains were lacking AB resistances and exhibited a PFGE genotype different from commercial starters. These strains, together with 17 S. equorum strains, were further studied for safety and technological characteristics. The ability to produce biogenic amines was not detected in any strain. PCR amplifications for enterotoxin encoding genes seg–sej were detected in one, and for δ-hemolysin encoding gene hld in four S. equorum strains, but phenotypic hemolytic activity was visible for three S. xylosus and 15 S. equorum strains. Catalase and nitrate reductase activity was observed in all isolates tested; particularly S. equorum showed high nitrate reduction. In conclusion, we were able to select four new Meat starter strains (two S. xylosus and two S. equorum strains) out of 116 investigated CNS, fulfilling all safety criteria including the absence of AB resistances, production of biogenic amines and genes encoding virulence factors but exhibiting high nitrate reductase and catalase activity as suitable technological characteristics. Thus, S. equorum isolates, often the dominant species in spontaneously Fermented Meat products, provided a prospective Meat starter species exhibiting high nitrate reduction and low prevalence of AB resistances.

  • identification of staphylococci and dominant lactic acid bacteria in spontaneously Fermented swiss Meat products using pcr rflp
    Food Microbiology, 2012
    Co-Authors: Esther Marty, Jasmin Buchs, Elisabeth Eugstermeier, Christophe Lacroix, Leo Meile
    Abstract:

    Abstract Pathogenic, spoilage, and technologically important microorganisms were monitored in 21 spontaneously Fermented Swiss Meat products manufactured with Meat from wildlife or animals grown in natural habitat. Thereby, PCR–restriction fragment length polymorphism (RFLP) on rpoB and 16S rRNA gene sequences provided a powerful tool for fast and accurate identification of the main microbial population. Lactobacillus sakei and Lactobacillus curvatus dominated in Fermented Meat products followed by Staphylococcus species, which constituted 88.2% of all Gram-positive, catalase-positive cocci (GCC + ) with cell counts varying from 2.6 to 7.0 log cfu/g during maturation. Staphylococcus equorum was prevalent in frequency and cell counts during maturation (18.0%; 5.0–7.3 log cfu/g) and in the end products (28.4%; 1.8–6.2 log cfu/g) implicating a new presumptive starter species for Meat fermentation. Nine out of 14 end products indicated safety risks to consumers due to the high incidence of Staphylococcus saprophyticus or Staphylococcus epidermidis combined with cell counts of 7.4 and 4.9 log cfu/g, respectively. This fact was supported by the detection of Staphylococcus aureus and Enterobacteriaceae in ready-to-eat products strongly exceeding the tolerable limit of 2 log cfu/g. Spontaneously Fermented Meat products produced from wildlife or animals grown in natural habitats not only gave rise to hygienic and safety concerns but also provided new presumptive starter strains.

Vânia Ferreira - One of the best experts on this subject based on the ideXlab platform.

  • diverse geno and phenotypes of persistent listeria monocytogenes isolates from Fermented Meat sausage production facilities in portugal
    Applied and Environmental Microbiology, 2011
    Co-Authors: Joana Barbosa, Vânia Ferreira, Paula Teixeira, Matthew J Stasiewicz, Kitiya Vongkamjan, Moreno A Switt, Tim Hogg, Paul Gibbs, Martin Wiedmann
    Abstract:

    The persistence of Listeria monocytogenes in food-associated environments represents a key factor in transmission of this pathogen. To identify persistent and transient strains associated with production of Fermented Meat sausages in northern Portugal, 1,723 L. monocytogenes isolates from raw material and finished products from 11 processors were initially characterized by random amplification of polymorphic DNA (RAPD), PCR-based molecular serotyping, and epidemic clone characterization, as well as cadmium, arsenic, and tetracycline resistance typing. Pulsed-field gel electrophoresis (PFGE) typing of 240 representative isolates provided evidence for persistence of L. monocytogenes for periods of time ranging from 10 to 32 months for all seven processors for which isolates from different production dates were available. Among 50 L. monocytogenes isolates that included one representative for each PFGE pattern obtained from a given sample, 12 isolates showed reduced invasion efficiency in Caco-2 cells, including 8 isolates with premature stop codons in inlA. Among 41 isolates representing sporadic and persistent PFGE types, 22 isolates represented lysogens. Neither strains with reduced invasion nor lysogens were overrepresented among persistent isolates. While the susceptibility of isolates to lysogenic phages also did not correlate with persistence, it appeared to be associated with molecular serotype. Our data show the following. (i) RAPD may not be suitable for analysis of large sets of L. monocytogenes isolates. (ii) While a large diversity of L. monocytogenes subtypes is found in Portuguese Fermented Meat sausages, persistence of L. monocytogenes in this food chain is common. (iii) Persistent L. monocytogenes strains are diverse and do not appear to be characterized by unique genetic or phenotypic characteristics.

  • antibiotic susceptibility of enterococci isolated from traditional Fermented Meat products
    Food Microbiology, 2009
    Co-Authors: Joana Barbosa, Vânia Ferreira, Paula Teixeira
    Abstract:

    Antibiotic susceptibility was evaluated for 182 Enterococcus spp. isolated from Alheira, Chourica de Vinhais and Salpicao de Vinhais, Fermented Meat products produced in the North of Portugal. Previously, a choice was made from a group of 1060 isolates, using phenotypic and genotypic tests. From these, 76 were previously identified as Enterococcus faecalis, 44 as Enterococcus faecium, one as Enterococcus casseliflavus and 61 as Enteroccocus spp. In order to encompass several of the known chemical and functional classes of antibiotics, resistance to ampicillin, penicillin G, ciprofloxacin, chloramphenicol, erythromycin, nitrofurantoin, rifampicin, tetracycline and vancomycin was evaluated. All the isolates were sensitive to antibiotics of clinical importance, such as penicillins and vancomycin. Some differences in Minimal Inhibitory Concentrations (MICs) of antibiotics, could be associated with the enterococcal species.

  • chemical and microbiological characterization of alheira a typical portuguese Fermented sausage with particular reference to factors relating to food safety
    Meat Science, 2006
    Co-Authors: Vânia Ferreira, Joana Barbosa, Tim Hogg, Paul Gibbs, Sandra Vendeiro, Ana Mota, Fatima Silva, Maria Joao Monteiro, Paula Teixeira
    Abstract:

    Abstract Alheiras are traditional smoked naturally Fermented Meat sausages produced in the north of Portugal. They have not previously been characterized as to their chemical and microbiological status. pH and salt levels are insufficient to assure microbiological safety, there is ample opportunity for post-cooking contamination; the products require chill storage and cooking before consumption. Heavy metals and biogenic amines were, in general, within accepted limits for Meat products. Lactic acid bacteria comprised the major microflora (ca. 7–8 log cfu/g) with substantial counts of micrococci and enterococci (up to 7 log cfu/g). Escherichia coli, Staphylococcus aureus and Listeria spp. were detected in several samples.