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Gale Brightwell - One of the best experts on this subject based on the ideXlab platform.
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The spoilage characteristics of Brochothrix thermosphacta and two psychrotolerant Enterobacteriacae in vacuum packed lamb and the comparison between high and low pH cuts.
Meat science, 2014Co-Authors: Amanda Gribble, John Mills, Gale BrightwellAbstract:Abstract The spoilage potential of Brochothrix thermosphacta, Serratia proteamaculans and Rahnella aquatilis was investigated in vacuum packaged high (5.9 to 6.4) and low (5.4 to 5.8) pH lamb. Vacuum packaged fore shank (m. extensor carpi radialis) and striploins (m. longissimus dorsi) (n = 306) inoculated with ~ 100 CFU of individual bacteria were stored for twelve weeks at temperatures − 1.5, 0, 2 and 7 °C. Spoilage characteristics and bacterial numbers were recorded and analysed in comparison to un-inoculated control samples. All three bacterial species were shown to grow in vacuum packaged lamb of pH values between 5.4 and 6.4, when stored at chilled temperatures (− 1.5 to 7 °C) for up to 84 days. B. thermosphacta and S. proteamaculans caused spoilage to the meat under these conditions whilst R. aquatilis spoiled high pH meat at 7 °C. These results go against previous beef models stipulating that Brochothrix and Enterobacteriacae species cannot grow on or cause spoilage of low pH meat in the absence of oxygen.
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spoilage characteristics of Brochothrix thermosphacta and campestris in chilled vacuum packaged lamb and their detection and identification by real time pcr
Meat Science, 2013Co-Authors: Amanda Gribble, Gale BrightwellAbstract:The spoilage potential of Brochothrix campestris and Brochothrix thermosphacta was investigated in vacuum-packed lamb. Striploins (n=338) were inoculated and stored for twelve weeks at temperatures -1.5, 0, 2 and 7 °C. Growth around 5-6 log10 CFU/cm(2) was recorded after six weeks at 0, 2 and 7 °C, and ~3 log10 CFU/cm(2) after nine weeks at -1.5 °C. B. campestris was shown to cause spoilage by nine weeks at temperatures above 0 °C by the presence of green drip and unacceptable odours. Molecular based assays for the detection and differentiation of B. thermosphacta and B. campestris were developed and validated. A TaqMan assay was designed to target a unique single-nucleotide polymorphism in the Brochothrix 16s rRNA gene with a sensitivity of <7 CFU per reaction. Secondly a specific PCR was designed for B. campestris targeting the structural genes, brcA and brcB. These testing regimes offer a rapid and cost effective method for the detection and screening of Brochothrix species in meat products and processing environments.
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Spoilage characteristics of Brochothrix thermosphacta and campestris in chilled vacuum packaged lamb, and their detection and identification by real time PCR.
Meat science, 2013Co-Authors: Amanda Gribble, Gale BrightwellAbstract:The spoilage potential of Brochothrix campestris and Brochothrix thermosphacta was investigated in vacuum-packed lamb. Striploins (n=338) were inoculated and stored for twelve weeks at temperatures -1.5, 0, 2 and 7 °C. Growth around 5-6 log10 CFU/cm(2) was recorded after six weeks at 0, 2 and 7 °C, and ~3 log10 CFU/cm(2) after nine weeks at -1.5 °C. B. campestris was shown to cause spoilage by nine weeks at temperatures above 0 °C by the presence of green drip and unacceptable odours. Molecular based assays for the detection and differentiation of B. thermosphacta and B. campestris were developed and validated. A TaqMan assay was designed to target a unique single-nucleotide polymorphism in the Brochothrix 16s rRNA gene with a sensitivity of
Amanda Gribble - One of the best experts on this subject based on the ideXlab platform.
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The spoilage characteristics of Brochothrix thermosphacta and two psychrotolerant Enterobacteriacae in vacuum packed lamb and the comparison between high and low pH cuts.
Meat science, 2014Co-Authors: Amanda Gribble, John Mills, Gale BrightwellAbstract:Abstract The spoilage potential of Brochothrix thermosphacta, Serratia proteamaculans and Rahnella aquatilis was investigated in vacuum packaged high (5.9 to 6.4) and low (5.4 to 5.8) pH lamb. Vacuum packaged fore shank (m. extensor carpi radialis) and striploins (m. longissimus dorsi) (n = 306) inoculated with ~ 100 CFU of individual bacteria were stored for twelve weeks at temperatures − 1.5, 0, 2 and 7 °C. Spoilage characteristics and bacterial numbers were recorded and analysed in comparison to un-inoculated control samples. All three bacterial species were shown to grow in vacuum packaged lamb of pH values between 5.4 and 6.4, when stored at chilled temperatures (− 1.5 to 7 °C) for up to 84 days. B. thermosphacta and S. proteamaculans caused spoilage to the meat under these conditions whilst R. aquatilis spoiled high pH meat at 7 °C. These results go against previous beef models stipulating that Brochothrix and Enterobacteriacae species cannot grow on or cause spoilage of low pH meat in the absence of oxygen.
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spoilage characteristics of Brochothrix thermosphacta and campestris in chilled vacuum packaged lamb and their detection and identification by real time pcr
Meat Science, 2013Co-Authors: Amanda Gribble, Gale BrightwellAbstract:The spoilage potential of Brochothrix campestris and Brochothrix thermosphacta was investigated in vacuum-packed lamb. Striploins (n=338) were inoculated and stored for twelve weeks at temperatures -1.5, 0, 2 and 7 °C. Growth around 5-6 log10 CFU/cm(2) was recorded after six weeks at 0, 2 and 7 °C, and ~3 log10 CFU/cm(2) after nine weeks at -1.5 °C. B. campestris was shown to cause spoilage by nine weeks at temperatures above 0 °C by the presence of green drip and unacceptable odours. Molecular based assays for the detection and differentiation of B. thermosphacta and B. campestris were developed and validated. A TaqMan assay was designed to target a unique single-nucleotide polymorphism in the Brochothrix 16s rRNA gene with a sensitivity of <7 CFU per reaction. Secondly a specific PCR was designed for B. campestris targeting the structural genes, brcA and brcB. These testing regimes offer a rapid and cost effective method for the detection and screening of Brochothrix species in meat products and processing environments.
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Spoilage characteristics of Brochothrix thermosphacta and campestris in chilled vacuum packaged lamb, and their detection and identification by real time PCR.
Meat science, 2013Co-Authors: Amanda Gribble, Gale BrightwellAbstract:The spoilage potential of Brochothrix campestris and Brochothrix thermosphacta was investigated in vacuum-packed lamb. Striploins (n=338) were inoculated and stored for twelve weeks at temperatures -1.5, 0, 2 and 7 °C. Growth around 5-6 log10 CFU/cm(2) was recorded after six weeks at 0, 2 and 7 °C, and ~3 log10 CFU/cm(2) after nine weeks at -1.5 °C. B. campestris was shown to cause spoilage by nine weeks at temperatures above 0 °C by the presence of green drip and unacceptable odours. Molecular based assays for the detection and differentiation of B. thermosphacta and B. campestris were developed and validated. A TaqMan assay was designed to target a unique single-nucleotide polymorphism in the Brochothrix 16s rRNA gene with a sensitivity of
Agnieszka Nowak - One of the best experts on this subject based on the ideXlab platform.
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Effects Of Thyme (Thymus Vulgaris L.) And Rosemary (Rosmarinus Officinalis L.) Essential Oils On Growth Of Brochothrix thermosphacta
African Journal of Microbiology Research, 2013Co-Authors: Agnieszka Nowak, Małgorzata Piotrowska, Danuta Kalemba, Agata CzyżowskaAbstract:The objective of the study was to investigate the chemical composition of Polish rosemary and thyme oils and to quantify the effects of these oils against Brochothrix thermosphacta. The major constituents of the thyme oil investigated were monoterpenes: thymol (29.4%) and p-cymene (21.6%). The rosemary oil represents 1,8-cineole chemotype (1,8-cineole 27.6%, limonene 13.5% and β-pinene 13.0%). The minimum inhibitory concentration (MIC) of thyme oil for B. thermosphacta is 0.05% and that of rosemary oil 0.5%. MIC values are not dependent on the temperature of the cultures or B. thermosphacta strain. However, the most significant influence of both oils on B. thermosphacta growth was observed at 4°C than at 25°C. Key words: Brochothrix thermosphacta, thyme oil, rosemary oil.
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The effects of thyme (Thymus vulgaris) and rosemary (Rosmarinus officinalis) essential oils on Brochothrix thermosphacta and on the shelf life of beef packaged in high-oxygen modified atmosphere.
Food microbiology, 2012Co-Authors: Agnieszka Nowak, Małgorzata Piotrowska, Danuta Kalemba, Lucjan Krala, Agata CzyżowskaAbstract:The objective of the study was to determine the Minimal Inhibitory Concentration (MIC) of thyme (29.4% thymol, 21.6% p-cymene) and rosemary essential oils (27.6% 1,8-cineole, 13.5% limonene, 13.0% β-pinene) against Brochothrix thermosphacta and to establish the feasibility of their use as components of modified atmosphere during beef refrigerated storage. The minimum inhibitory concentration (MIC) of thyme oil against B. thermosphacta is 0.05% and that of rosemary oil 0.5%. The MIC values are independent on strain and temperature of growth, however the bactericidal effects are strain dependent. The addition of any of oil at a concentration equal to 2MIC to the modified atmosphere (80% O(2)/20% CO(2)) does not significantly influence the microbial quality of meat. At the same time, such a concentration of the essential oils was considerably detrimental to the organoleptic factors.
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The prevalence and some metabolic traits of Brochothrix thermosphacta in meat and meat products packaged in different ways.
Journal of the science of food and agriculture, 2011Co-Authors: Agnieszka Nowak, Anna Rygala, Elzbieta Oltuszak-walczak, Piotr WalczakAbstract:BACKGROUND: The effect of Brochothrix thermosphacta on the quality of meat and meat products is of vital importance in connection with Regulation EC/178/2002 extending the definition of unsafe foodstuffs to encompass all those which are unfit for human consumption. This study aimed to determine the prevalence of B. thermosphacta in meat and meat products packaged under different conditions and to estimate the effect of B. thermosphacta strains on product quality based on their protein and lipid degradation activity. RESULTS:B. thermosphacta was absent in only two of 132 samples. All other samples were contaminated with this bacterium (101 to 109cfu g−1 meat and 102 to 108cfu g−1meat product). In products stored under high-oxygen atmosphere Brochothrix cells accounted for almost 100% total mesophilic count (TMC) and below 50% TMC in oxygen-free atmosphere. While the tested B. thermosphacta strains did not show any proteolytic activity, most of them displayed lipolytic activity at 25 °C and some even at 4 °C. CONCLUSION:B. thermosphacta is commonly present in meat and meat products packaged in different ways. This bacterium can display lipolytic activity also at refrigeration temperature. Its over-proliferation can be inhibited through vacuum packaging or packaging under a modified atmosphere with reduced oxygen content. Copyright © 2011 Society of Chemical Industry
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Biochemical activities of Brochothrix thermosphacta.
Meat science, 2011Co-Authors: Agnieszka Nowak, Małgorzata PiotrowskaAbstract:Abstract Activities of 19 hydrolases were estimated in cell suspensions of 40 Brochothrix thermosphacta strains, isolated from meat and meat products packaged under various conditions, by using API ZYM® test. These strains produced: acidic phosphatase, esterase C4, esterase/lipase C8, α-chymotrypsin, leucine arylamidase, β-glucosidase and α-glucosidase. The predominating biotype produced only the first four of the listed enzymes. The extracellular lipolytic activity for bromo-chloro-indolyl-caprylate was detected only in culture broth supernatants of 4 strains thereby indicating that esterase/lipase C8 is cell-bound. 13 of the strains displayed proteolytic activity for albumin at 4 °C (0.31–2.07 U) while 9 strains showed this activity at 25 °C (0.11–1.21 U). Only 4 strains digested albumin at both temperatures. Thus the meat spoilage potential of B. thermosphacta strains results not only from digestion of carbohydrates but also from their proteolytic activity.
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In vitro synthesis of biogenic amines by Brochothrix thermosphacta isolates from meat and meat products and the influence of other microorganisms
Meat science, 2011Co-Authors: Agnieszka Nowak, Agata CzyżowskaAbstract:Abstract Twenty Brochothrix thermosphacta strains tested for biogenic amines (BAs) production, formed histamine (6.6–16.2 mg/kg) and tyramine (18.7–35.4 mg/kg) but neither putrescine nor cadaverine. Six of the twenty strains were also investigated in respect of their influence on the synthesis of BAs by Escherichia coli , Pseudomonas sp., Proteus mirabilis and Lactobacillus sakei . In pure culture Escherichia coli produced all of the studied amines (histamine, tyramine, putrescine and cadaverine) with a total concentration of 167.7 mg/kg, P. mirabilis produced a total of 56.7 mg/kg histamine, tyramine and cadaverine, while Lactobacillus sakei and Pseudomonas sp. produced histamine and tyramine, totaling 37.9 and 35.2 mg/kg respectively. All B. thermosphacta promoted cadaverine production by Escherichia coli which increased by 12–68% , and some of them contributed to the appearance of this amine among the metabolites of Pseudomonas . The presence of B. thermosphacta decreased the potential ability of P. mirabilis to produce BAs.
Agata Czyżowska - One of the best experts on this subject based on the ideXlab platform.
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Effects Of Thyme (Thymus Vulgaris L.) And Rosemary (Rosmarinus Officinalis L.) Essential Oils On Growth Of Brochothrix thermosphacta
African Journal of Microbiology Research, 2013Co-Authors: Agnieszka Nowak, Małgorzata Piotrowska, Danuta Kalemba, Agata CzyżowskaAbstract:The objective of the study was to investigate the chemical composition of Polish rosemary and thyme oils and to quantify the effects of these oils against Brochothrix thermosphacta. The major constituents of the thyme oil investigated were monoterpenes: thymol (29.4%) and p-cymene (21.6%). The rosemary oil represents 1,8-cineole chemotype (1,8-cineole 27.6%, limonene 13.5% and β-pinene 13.0%). The minimum inhibitory concentration (MIC) of thyme oil for B. thermosphacta is 0.05% and that of rosemary oil 0.5%. MIC values are not dependent on the temperature of the cultures or B. thermosphacta strain. However, the most significant influence of both oils on B. thermosphacta growth was observed at 4°C than at 25°C. Key words: Brochothrix thermosphacta, thyme oil, rosemary oil.
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The effects of thyme (Thymus vulgaris) and rosemary (Rosmarinus officinalis) essential oils on Brochothrix thermosphacta and on the shelf life of beef packaged in high-oxygen modified atmosphere.
Food microbiology, 2012Co-Authors: Agnieszka Nowak, Małgorzata Piotrowska, Danuta Kalemba, Lucjan Krala, Agata CzyżowskaAbstract:The objective of the study was to determine the Minimal Inhibitory Concentration (MIC) of thyme (29.4% thymol, 21.6% p-cymene) and rosemary essential oils (27.6% 1,8-cineole, 13.5% limonene, 13.0% β-pinene) against Brochothrix thermosphacta and to establish the feasibility of their use as components of modified atmosphere during beef refrigerated storage. The minimum inhibitory concentration (MIC) of thyme oil against B. thermosphacta is 0.05% and that of rosemary oil 0.5%. The MIC values are independent on strain and temperature of growth, however the bactericidal effects are strain dependent. The addition of any of oil at a concentration equal to 2MIC to the modified atmosphere (80% O(2)/20% CO(2)) does not significantly influence the microbial quality of meat. At the same time, such a concentration of the essential oils was considerably detrimental to the organoleptic factors.
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In vitro synthesis of biogenic amines by Brochothrix thermosphacta isolates from meat and meat products and the influence of other microorganisms
Meat science, 2011Co-Authors: Agnieszka Nowak, Agata CzyżowskaAbstract:Abstract Twenty Brochothrix thermosphacta strains tested for biogenic amines (BAs) production, formed histamine (6.6–16.2 mg/kg) and tyramine (18.7–35.4 mg/kg) but neither putrescine nor cadaverine. Six of the twenty strains were also investigated in respect of their influence on the synthesis of BAs by Escherichia coli , Pseudomonas sp., Proteus mirabilis and Lactobacillus sakei . In pure culture Escherichia coli produced all of the studied amines (histamine, tyramine, putrescine and cadaverine) with a total concentration of 167.7 mg/kg, P. mirabilis produced a total of 56.7 mg/kg histamine, tyramine and cadaverine, while Lactobacillus sakei and Pseudomonas sp. produced histamine and tyramine, totaling 37.9 and 35.2 mg/kg respectively. All B. thermosphacta promoted cadaverine production by Escherichia coli which increased by 12–68% , and some of them contributed to the appearance of this amine among the metabolites of Pseudomonas . The presence of B. thermosphacta decreased the potential ability of P. mirabilis to produce BAs.
Graciela Vignolo - One of the best experts on this subject based on the ideXlab platform.
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seleccion de un modelo primario para describir la curva de crecimiento de bacterias lacticas y Brochothrix thermosphacta sobre emulsiones carnicas cocidas
Información tecnológica, 2007Co-Authors: Maria Elisa Cayre, Graciela Vignolo, Oscar Alfredo GarroAbstract:Resumen Se han comparado tres modelos primarios para describir la curva de crecimiento de bacterias lacticas y Brochothrix thermosphacta sobre emulsiones carnicas cocidas y para estimar los parametros cineticos de crecimiento: tiempo de latencia (λ), maxima velocidad especifica de crecimiento ( µ max ) y maxima densidad bacteriana ( y ma x ). Se usaron los modelos Logistico, Gompertz y Baranyi y se comparo la bondad de ajuste de los modelos, la incertidumbre y precision de las estimaciones. Los modelos de Gompertz y Baranyi produjeron los mejores ajustes en la mayoria de los casos presentados. No se detectaron diferencias apreciables entre los modelos en relacion a la incertidumbre y precision de las estimaciones de y ma x y µ max . Sin embargo, las estimaciones de λ dadas por el modelo de Baranyi fueron menos exactas y los resultados muestran que el modelo de Gompertz mostro un mejor comportamiento. Palabras claves: curva de crecimiento, bacterias lacticas, Brochothrix thermosphacta, modelado,
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inhibition of listeria innocua and Brochothrix thermosphacta in vacuum packaged meat by addition of bacteriocinogenic lactobacillus curvatus crl705 and its bacteriocins
Letters in Applied Microbiology, 2006Co-Authors: P Castellano, Graciela VignoloAbstract:Aims: To evaluate the inhibition effectiveness of Lactobacillus curvatus CRL705 used as a bioprotective culture and of its bacteriocins, lactocin 705 and lactocin AL705, against Listeria innocua, Brochothrix thermosphacta and indigenous lactic acid bacteria (LAB) in vacuum-packaged meat stored at 2°C. Methods and Results: The live culture of Lact. curvatus CRL705 as well as synthetic lactocin 705 and purified lactocin AL705 were shown to be similarly effective in preventing the growth of B. thermosphacta and L. innocua in meat discs in contrast to control samples in which these micro-organisms grew rapidly, their numbers increasing by 3·0- and 2·1-log cycles respectively. In addition, indigenous LAB population showed a lower growth rate in the presence of lactocin 705. Bacteriocin activity was detected in the meat discs during 36 days at 2°C irrespective of the biopreservation strategy applied. Changes in pH were not significantly different in meat discs treated with the protective culture when compared with control samples. Conclusions: Lactobacillus curvatus CRL705 and the produced bacteriocins, lactocin 705 and lactocin AL 705, were effective in inhibiting L. innocua and B. thermosphacta. The use of the bioprotective culture in refrigerated vacuum-packaged fresh meat would be more feasible from an economic and legal point of view. Significance and Impact of the Study: Establishment of biopreservation as a method to ensure the microbiological safety of vacuum-packaged fresh meat at 2°C.
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Effect of storage temperature and gas permeability of packaging film on the growth of lactic acid bacteria and Brochothrix thermosphacta in cooked meat emulsions
Food Microbiology, 2005Co-Authors: Maria Elisa Cayre, Oscar Alfredo Garro, Graciela VignoloAbstract:The effect of gas permeability of packaging film on the growth of lactic acid bacteria and Brochothrix thermosphacta in cooked meat emulsions stored at 0, 8 and 151C was investigated. The estimated parameters from Gompertz equation for the assayed temperature–oxygen permeability combinations showed LAB development to be significantly greater than those of B. thermosphacta. The influence of the two sources of variation (oxygen permeability of packaging film and temperature) on the growth parameters of LAB and B. thermosphacta was analysed showing a significant effect (Po0:001) of the temperature on both bacterial population while the film permeability had only a significant influence (Po0:001) on B. thermosphacta growth. Under the conditions of this study the packaging film influenced the maximum counts and growth rates of both organisms. Since the inhibition of B. thermosphacta occurred when the meat product was vacuum-packaged in films possessing high oxygen permeability and the effect of pH was found not to be associated with the growth inhibition, accumulation of hydrogen peroxide produced by LAB may possibly be one of the main factors responsible for B. thermosphacta inhibition. Shelf-life of vacuum-packaged cooked meat emulsions in high oxygen transmission rate films will be guarantied and a temperature abuse will not result in an increase of spoilage by LAB. r 2005 Elsevier Ltd. All rights reserved.
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Growth of Brochothrix thermosphacta and Lactobacillus sake in refrigerated vacuum-packaged meat
1999Co-Authors: Graciela Vignolo, Aida P. De Ruiz Holgado, G. OliverAbstract:The growth rates of various strains of Lactobacillus sake and Brochothrix thermosphacta, inoculated on a vacuum-packaged beef semimembranosus muscle and incubated at 2°C for 18 days, were determined. B. thermosphacta grew more rapidly and had a shorter lag phase when compared to L. sake. Addition of peptone to the substrate, but not glucose, markedly favored the growth of L. sake. Growth of Lactobacillus cells was also positively affected when the meat slices were pre-incubated at 25°C for 24 h before inoculation. In these conditions, the growth of L. sake was higher than that of B. thermosphacta after 7 days and the final cell density at the 18 th day was about 1.10 8 cfu/cm 2 .
