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Arie H Havelaar - One of the best experts on this subject based on the ideXlab platform.
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explanatory variables associated with campylobacter and escherichia coli concentrations on broiler chicken carcasses during processing in two slaughterhouses
Journal of Food Protection, 2016Co-Authors: Ewa Pacholewicz, Arno Swart, Jaap A Wagenaar, Arie H Havelaar, L J A LipmanAbstract:This study aimed at identifying explanatory variables that were associated with Campylobacter and Escherichia coli concentrations throughout processing in two commercial broiler slaughterhouses. Quantative data on Campylobacter and E. coli along the processing line were collected. Moreover, information on batch characteristics, slaughterhouse practices, process performance, and environmental variables was collected through questionnaires, observations, and measurements, resulting in data on 19 potential explanatory variables. Analysis was conducted separately in each slaughterhouse to identify which variables were related to changes in concentrations of Campylobacter and E. coli during the processing steps: scalding, Defeathering, evisceration, and chilling. Associations with explanatory variables were different in the slaughterhouses studied. In the first slaughterhouse, there was only one significant association: poorer uniformity of the weight of carcasses within a batch with less decrease in E. coli concentrations after Defeathering. In the second slaughterhouse, significant statistical associations were found with variables, including age, uniformity, average weight of carcasses, Campylobacter concentrations in excreta and ceca, and E. coli concentrations in excreta. Bacterial concentrations in excreta and ceca were found to be the most prominent variables, because they were associated with concentration on carcasses at various processing points. Although the slaughterhouses produced specific products and had different batch characteristics and processing parameters, the effect of the significant variables was not always the same for each slaughterhouse. Therefore, each slaughterhouse needs to determine its particular relevant measures for hygiene control and process management. This identification could be supported by monitoring changes in bacterial concentrations during processing in individual slaughterhouses. In addition, the possibility that management and food handling practices in slaughterhouses contribute to the differences in bacterial contamination between slaughterhouses needs further investigation.
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reduction of extended spectrum β lactamase and ampc β lactamase producing escherichia coli through processing in two broiler chicken slaughterhouses
International Journal of Food Microbiology, 2015Co-Authors: Ewa Pacholewicz, Arno Swart, Betty G M Gortemaker, Arie H Havelaar, Apostolos Liakopoulos, Cindy Dierikx, Heike SchmittAbstract:Whilst broilers are recognised as a reservoir of extended-spectrum-β-lactamase (ESBL)- and AmpC-β-lactamase (AmpC)-producing Escherichia coli, there is currently limited knowledge on the effect of slaughtering on its concentrations on poultry meat. The aim of this study was to establish the concentration of ESBL/AmpC producing E. coli on broiler chicken carcasses through processing. In addition the changes in ESBL/AmpC producing E. coli concentrations were compared with generic E. coli and Campylobacter. In two slaughterhouses, the surface of the whole carcasses was sampled after 5 processing steps: bleeding, scalding, Defeathering, evisceration and chilling. In total, 17 batches were sampled in two different slaughterhouses during the summers of 2012 and 2013. ESBL/AmpC producing E. coli was enumerated on MacConkey agar with 1mg/l cefotaxime, and the ESBL/AmpC phenotypes and genotypes were characterised. The ESBL/AmpC producing E. coli concentrations varied significantly between the incoming batches in both slaughterhouses. The concentrations on broiler chicken carcasses were significantly reduced during processing. In Slaughterhouse 1, all subsequent processing steps reduced the concentrations except evisceration which led to a slight increase that was statistically not significant. The changes in concentration between processing steps were relatively similar for all sampled batches in this slaughterhouse. In contrast, changes varied between batches in Slaughterhouse 2, and the overall reduction through processing was higher in Slaughterhouse 2. Changes in ESBL/AmpC producing E. coli along the processing line were similar to changes in generic E. coli in both slaughterhouses. The effect of Defeathering differed between ESBL/AmpC producing E. coli and Campylobacter. ESBL/AmpC producing E. coli decreased after Defeathering, whereas Campylobacter concentrations increased. The genotypes of ESBL/AmpC producing E. coli (blaCTX-M-1, blaSHV-12, blaCMY-2, blaTEM-52c, blaTEM-52cvar) from both slaughterhouses match typical poultry genotypes. Their distribution differed between batches and changed throughout processing for some batches. The concentration levels found after chilling were between 10(2) and 10(5)CFU/carcass. To conclude, changes in ESBL/AmpC producing E. coli concentrations on broiler chicken carcasses during processing are influenced by batch and slaughterhouse, pointing to the role of both primary production and process control for reducing ESBL/AmpC producing E. coli levels in final products. Due to similar changes upon processing, E. coli can be used as a process indicator of ESBL/AmpC producing E. coli, because the processing steps had similar impact on both organisms. Cross contamination may potentially explain shifts in genotypes within some batches through the processing.
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a comparison of fluctuations of campylobacter and escherichia coli concentrations on broiler chicken carcasses during processing in two slaughterhouses
International Journal of Food Microbiology, 2015Co-Authors: Ewa Pacholewicz, Arno Swart, Maarten Schipper, Betty G M Gortemaker, Jaap A Wagenaar, Arie H Havelaar, L J A LipmanAbstract:The causes of differences in Campylobacter and Escherichia coli concentrations on broiler chicken carcasses after chilling between slaughterhouses are not fully identified. Therefore, it is a challenge for slaughterhouses to comply with Process Hygiene Criteria for broiler meat. The aim of the study was to identify which processing steps contribute to increases or decreases in Campylobacter and E. coli concentrations within and between two slaughterhouses. Identifying the processing steps with variable performance could explain the differences in bacterial concentrations after chilling between slaughterhouses. Thermotolerant Campylobacter and E. coli concentrations on carcasses during broiler processing were measured during the summer period in 21 trials after bleeding, scalding, Defeathering, evisceration and chilling. In two slaughterhouses with comparable Campylobacter and E. coli concentrations in the incoming batches (after bleeding), the mean log10 concentrations are found to be significantly different after chilling. Campylobacter concentrations decreased by 1.40 log10 in Slaughterhouse 1 and by 1.86 log10 in Slaughterhouse 2, whereas E. coli decreased by 2.19 log10 in Slaughterhouse 1 and by 2.84 log10 in Slaughterhouse 2. Higher concentrations of Campylobacter and E. coli on carcasses after chilling were observed in Slaughterhouse 1 in which an increase in concentrations was observed after evisceration. The effect of processing on Campylobacter and E. coli concentrations in Slaughterhouse 1 did not differ between batches. In Slaughterhouse 2, the effect of processing on the concentrations of both bacteria varied over batches. Changes in E. coli concentration levels during processing were similar to Campylobacter except for Defeathering. E. coli concentration significantly decreased after Defeathering in both slaughterhouses, whereas Campylobacter increased in Slaughterhouse 2 and in Slaughterhouse 1 no significant changes were observed. The patterns of increases and decreases in bacterial concentrations during processing are specific for each slaughterhouse. Inhomogeneous patterns potentially explain the differences in concentrations after chilling between slaughterhouses. Critical processing steps should be validated in each slaughterhouse by longitudinal studies and potentially based on E. coli. E. coli has a potential to be used as an indicator of processing hygiene, because the impact of most of the studied processing steps was similar as for Campylobacter.
Ewa Pacholewicz - One of the best experts on this subject based on the ideXlab platform.
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Reviewing Interventions against Enterobacteriaceae in Broiler Processing: Using Old Techniques for Meeting the New Challenges of ESBL E. coli?
Hindawi Limited, 2018Co-Authors: Michaela Projahn, Ewa Pacholewicz, Evelyne Becker, Guido Correia-carreira, Niels Bandick, Annemarie KaesbohrerAbstract:Extended-spectrum beta-lactamase- (ESBL-) producing Enterobacteriaceae are frequently detected in poultry and fresh chicken meat. Due to the high prevalence, an impact on human colonization and the spread of antibiotic resistance into the environment is assumed. ESBL-producing Enterobacteriaceae can be transmitted along the broiler production chain but also their persistence is reported because of insufficient cleaning and disinfection. Processing of broiler chickens leads to a reduction of microbiological counts on the carcasses. However, processing steps like scalding, Defeathering, and evisceration are critical concerning fecal contamination and, therefore, cross-contamination with bacterial strains. Respective intervention measures along the slaughter processing line aim at reducing the microbiological load on broiler carcasses as well as preventing cross-contamination. Published data on the impact of possible intervention measures against ESBL-producing Enterobacteriaceae are missing and, therefore, we focused on processing measures concerning Enterobacteriaceae, in particular E. coli or coliform counts, during processing of broiler chickens to identify possible hints for effective strategies to reduce these resistant bacteria. In total, 73 publications were analyzed and data on the quantitative reductions were extracted. Most investigations concentrated on scalding, postDefeathering washes, and improvements in the chilling process and were already published in and before 2008 (n=42, 58%). Therefore, certain measures may be already installed in slaughterhouse facilities today. The effect on eliminating ESBL-producing Enterobacteriaceae is questionable as there are still positive chicken meat samples found. A huge number of studies dealt with different applications of chlorine substances which are not approved in the European Union and the reduction level did not exceed 3 log10 values. None of the measures was able to totally eradicate Enterobacteriaceae from the broiler carcasses indicating the need to develop intervention measures to prevent contamination with ESBL-producing Enterobacteriaceae and, therefore, the exposure of humans and the further release of antibiotic resistances into the environment
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explanatory variables associated with campylobacter and escherichia coli concentrations on broiler chicken carcasses during processing in two slaughterhouses
Journal of Food Protection, 2016Co-Authors: Ewa Pacholewicz, Arno Swart, Jaap A Wagenaar, Arie H Havelaar, L J A LipmanAbstract:This study aimed at identifying explanatory variables that were associated with Campylobacter and Escherichia coli concentrations throughout processing in two commercial broiler slaughterhouses. Quantative data on Campylobacter and E. coli along the processing line were collected. Moreover, information on batch characteristics, slaughterhouse practices, process performance, and environmental variables was collected through questionnaires, observations, and measurements, resulting in data on 19 potential explanatory variables. Analysis was conducted separately in each slaughterhouse to identify which variables were related to changes in concentrations of Campylobacter and E. coli during the processing steps: scalding, Defeathering, evisceration, and chilling. Associations with explanatory variables were different in the slaughterhouses studied. In the first slaughterhouse, there was only one significant association: poorer uniformity of the weight of carcasses within a batch with less decrease in E. coli concentrations after Defeathering. In the second slaughterhouse, significant statistical associations were found with variables, including age, uniformity, average weight of carcasses, Campylobacter concentrations in excreta and ceca, and E. coli concentrations in excreta. Bacterial concentrations in excreta and ceca were found to be the most prominent variables, because they were associated with concentration on carcasses at various processing points. Although the slaughterhouses produced specific products and had different batch characteristics and processing parameters, the effect of the significant variables was not always the same for each slaughterhouse. Therefore, each slaughterhouse needs to determine its particular relevant measures for hygiene control and process management. This identification could be supported by monitoring changes in bacterial concentrations during processing in individual slaughterhouses. In addition, the possibility that management and food handling practices in slaughterhouses contribute to the differences in bacterial contamination between slaughterhouses needs further investigation.
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reduction of extended spectrum β lactamase and ampc β lactamase producing escherichia coli through processing in two broiler chicken slaughterhouses
International Journal of Food Microbiology, 2015Co-Authors: Ewa Pacholewicz, Arno Swart, Betty G M Gortemaker, Arie H Havelaar, Apostolos Liakopoulos, Cindy Dierikx, Heike SchmittAbstract:Whilst broilers are recognised as a reservoir of extended-spectrum-β-lactamase (ESBL)- and AmpC-β-lactamase (AmpC)-producing Escherichia coli, there is currently limited knowledge on the effect of slaughtering on its concentrations on poultry meat. The aim of this study was to establish the concentration of ESBL/AmpC producing E. coli on broiler chicken carcasses through processing. In addition the changes in ESBL/AmpC producing E. coli concentrations were compared with generic E. coli and Campylobacter. In two slaughterhouses, the surface of the whole carcasses was sampled after 5 processing steps: bleeding, scalding, Defeathering, evisceration and chilling. In total, 17 batches were sampled in two different slaughterhouses during the summers of 2012 and 2013. ESBL/AmpC producing E. coli was enumerated on MacConkey agar with 1mg/l cefotaxime, and the ESBL/AmpC phenotypes and genotypes were characterised. The ESBL/AmpC producing E. coli concentrations varied significantly between the incoming batches in both slaughterhouses. The concentrations on broiler chicken carcasses were significantly reduced during processing. In Slaughterhouse 1, all subsequent processing steps reduced the concentrations except evisceration which led to a slight increase that was statistically not significant. The changes in concentration between processing steps were relatively similar for all sampled batches in this slaughterhouse. In contrast, changes varied between batches in Slaughterhouse 2, and the overall reduction through processing was higher in Slaughterhouse 2. Changes in ESBL/AmpC producing E. coli along the processing line were similar to changes in generic E. coli in both slaughterhouses. The effect of Defeathering differed between ESBL/AmpC producing E. coli and Campylobacter. ESBL/AmpC producing E. coli decreased after Defeathering, whereas Campylobacter concentrations increased. The genotypes of ESBL/AmpC producing E. coli (blaCTX-M-1, blaSHV-12, blaCMY-2, blaTEM-52c, blaTEM-52cvar) from both slaughterhouses match typical poultry genotypes. Their distribution differed between batches and changed throughout processing for some batches. The concentration levels found after chilling were between 10(2) and 10(5)CFU/carcass. To conclude, changes in ESBL/AmpC producing E. coli concentrations on broiler chicken carcasses during processing are influenced by batch and slaughterhouse, pointing to the role of both primary production and process control for reducing ESBL/AmpC producing E. coli levels in final products. Due to similar changes upon processing, E. coli can be used as a process indicator of ESBL/AmpC producing E. coli, because the processing steps had similar impact on both organisms. Cross contamination may potentially explain shifts in genotypes within some batches through the processing.
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a comparison of fluctuations of campylobacter and escherichia coli concentrations on broiler chicken carcasses during processing in two slaughterhouses
International Journal of Food Microbiology, 2015Co-Authors: Ewa Pacholewicz, Arno Swart, Maarten Schipper, Betty G M Gortemaker, Jaap A Wagenaar, Arie H Havelaar, L J A LipmanAbstract:The causes of differences in Campylobacter and Escherichia coli concentrations on broiler chicken carcasses after chilling between slaughterhouses are not fully identified. Therefore, it is a challenge for slaughterhouses to comply with Process Hygiene Criteria for broiler meat. The aim of the study was to identify which processing steps contribute to increases or decreases in Campylobacter and E. coli concentrations within and between two slaughterhouses. Identifying the processing steps with variable performance could explain the differences in bacterial concentrations after chilling between slaughterhouses. Thermotolerant Campylobacter and E. coli concentrations on carcasses during broiler processing were measured during the summer period in 21 trials after bleeding, scalding, Defeathering, evisceration and chilling. In two slaughterhouses with comparable Campylobacter and E. coli concentrations in the incoming batches (after bleeding), the mean log10 concentrations are found to be significantly different after chilling. Campylobacter concentrations decreased by 1.40 log10 in Slaughterhouse 1 and by 1.86 log10 in Slaughterhouse 2, whereas E. coli decreased by 2.19 log10 in Slaughterhouse 1 and by 2.84 log10 in Slaughterhouse 2. Higher concentrations of Campylobacter and E. coli on carcasses after chilling were observed in Slaughterhouse 1 in which an increase in concentrations was observed after evisceration. The effect of processing on Campylobacter and E. coli concentrations in Slaughterhouse 1 did not differ between batches. In Slaughterhouse 2, the effect of processing on the concentrations of both bacteria varied over batches. Changes in E. coli concentration levels during processing were similar to Campylobacter except for Defeathering. E. coli concentration significantly decreased after Defeathering in both slaughterhouses, whereas Campylobacter increased in Slaughterhouse 2 and in Slaughterhouse 1 no significant changes were observed. The patterns of increases and decreases in bacterial concentrations during processing are specific for each slaughterhouse. Inhomogeneous patterns potentially explain the differences in concentrations after chilling between slaughterhouses. Critical processing steps should be validated in each slaughterhouse by longitudinal studies and potentially based on E. coli. E. coli has a potential to be used as an indicator of processing hygiene, because the impact of most of the studied processing steps was similar as for Campylobacter.
Jaap A Wagenaar - One of the best experts on this subject based on the ideXlab platform.
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explanatory variables associated with campylobacter and escherichia coli concentrations on broiler chicken carcasses during processing in two slaughterhouses
Journal of Food Protection, 2016Co-Authors: Ewa Pacholewicz, Arno Swart, Jaap A Wagenaar, Arie H Havelaar, L J A LipmanAbstract:This study aimed at identifying explanatory variables that were associated with Campylobacter and Escherichia coli concentrations throughout processing in two commercial broiler slaughterhouses. Quantative data on Campylobacter and E. coli along the processing line were collected. Moreover, information on batch characteristics, slaughterhouse practices, process performance, and environmental variables was collected through questionnaires, observations, and measurements, resulting in data on 19 potential explanatory variables. Analysis was conducted separately in each slaughterhouse to identify which variables were related to changes in concentrations of Campylobacter and E. coli during the processing steps: scalding, Defeathering, evisceration, and chilling. Associations with explanatory variables were different in the slaughterhouses studied. In the first slaughterhouse, there was only one significant association: poorer uniformity of the weight of carcasses within a batch with less decrease in E. coli concentrations after Defeathering. In the second slaughterhouse, significant statistical associations were found with variables, including age, uniformity, average weight of carcasses, Campylobacter concentrations in excreta and ceca, and E. coli concentrations in excreta. Bacterial concentrations in excreta and ceca were found to be the most prominent variables, because they were associated with concentration on carcasses at various processing points. Although the slaughterhouses produced specific products and had different batch characteristics and processing parameters, the effect of the significant variables was not always the same for each slaughterhouse. Therefore, each slaughterhouse needs to determine its particular relevant measures for hygiene control and process management. This identification could be supported by monitoring changes in bacterial concentrations during processing in individual slaughterhouses. In addition, the possibility that management and food handling practices in slaughterhouses contribute to the differences in bacterial contamination between slaughterhouses needs further investigation.
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a comparison of fluctuations of campylobacter and escherichia coli concentrations on broiler chicken carcasses during processing in two slaughterhouses
International Journal of Food Microbiology, 2015Co-Authors: Ewa Pacholewicz, Arno Swart, Maarten Schipper, Betty G M Gortemaker, Jaap A Wagenaar, Arie H Havelaar, L J A LipmanAbstract:The causes of differences in Campylobacter and Escherichia coli concentrations on broiler chicken carcasses after chilling between slaughterhouses are not fully identified. Therefore, it is a challenge for slaughterhouses to comply with Process Hygiene Criteria for broiler meat. The aim of the study was to identify which processing steps contribute to increases or decreases in Campylobacter and E. coli concentrations within and between two slaughterhouses. Identifying the processing steps with variable performance could explain the differences in bacterial concentrations after chilling between slaughterhouses. Thermotolerant Campylobacter and E. coli concentrations on carcasses during broiler processing were measured during the summer period in 21 trials after bleeding, scalding, Defeathering, evisceration and chilling. In two slaughterhouses with comparable Campylobacter and E. coli concentrations in the incoming batches (after bleeding), the mean log10 concentrations are found to be significantly different after chilling. Campylobacter concentrations decreased by 1.40 log10 in Slaughterhouse 1 and by 1.86 log10 in Slaughterhouse 2, whereas E. coli decreased by 2.19 log10 in Slaughterhouse 1 and by 2.84 log10 in Slaughterhouse 2. Higher concentrations of Campylobacter and E. coli on carcasses after chilling were observed in Slaughterhouse 1 in which an increase in concentrations was observed after evisceration. The effect of processing on Campylobacter and E. coli concentrations in Slaughterhouse 1 did not differ between batches. In Slaughterhouse 2, the effect of processing on the concentrations of both bacteria varied over batches. Changes in E. coli concentration levels during processing were similar to Campylobacter except for Defeathering. E. coli concentration significantly decreased after Defeathering in both slaughterhouses, whereas Campylobacter increased in Slaughterhouse 2 and in Slaughterhouse 1 no significant changes were observed. The patterns of increases and decreases in bacterial concentrations during processing are specific for each slaughterhouse. Inhomogeneous patterns potentially explain the differences in concentrations after chilling between slaughterhouses. Critical processing steps should be validated in each slaughterhouse by longitudinal studies and potentially based on E. coli. E. coli has a potential to be used as an indicator of processing hygiene, because the impact of most of the studied processing steps was similar as for Campylobacter.
Hoffmann, Fernando Leite - One of the best experts on this subject based on the ideXlab platform.
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Identificação de microorganismos isolados de agua, gelo e carcaças de frangos em diferentes fases de processamento
[s.n.], 2018Co-Authors: Hoffmann, Fernando LeiteAbstract:Orientador : Vanderlei Perez CanhosDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: Objetivou-se, no presente trabalho, a identificação dos principais microrganismos encontrados nas diversas fases de processamento de frangos. Para tal, realizaram-se conta¬gens totais de microrganismos e contagens totais de psicrotróficos da água do escaldador, água de abastecimento, água de ¿chiller", gelo, aves inteiras após a depenação, aves evisceradas após a passagem pelo "chiller" e antes de serem embaladas. Foram constatadas similaridades entre as contagens totais obtidas e as apresentadas na literatura. O meio de cultura Cristal Violeta Tetrazólio, sugerido para contagens de psicrotróficos, mostrou-se eficaz, na inibição de crescimento de microrganismos Gram positivos. Através de testes morfológicos e bioquímicos realizados nos microrganismos isolados, foram identificadas bactérias dos gêneros: Staphylococcus, Acetobacter, e os psicrotróficos: Achromobacter, Aeromonas e PseudomonasAbstract: The objective of the present work was to identify the main contaminant microbial flora found at the different stages of poultry processing. Total counts and psychrotrophic total counts were carried out in the scalding water, washing water, chiller water and slush-ice also in the entire chicken after Defeathering and eviscerated chicken after chilling and before packaging. Similarities were found among the total counts determined and the ones reported in the literature. Crystal Violet Tetrazolium media suggested for psychrotrophic count was efficient to inhibit growth of Gram positive organisms. The isolated organisms were examined by biochemical and morphological tests, and microorganisms of the genus Staphylococcus, Acetobacter and the psychrotrophic Achromobacter, Aeromonas and Pseudomonas were identifiedMestradoMestre em Ciência de Alimento
Fernando Leite Hoffmann - One of the best experts on this subject based on the ideXlab platform.
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Identificação de microorganismos isolados de agua, gelo e carcaças de frangos em diferentes fases de processamento
2017Co-Authors: Fernando Leite HoffmannAbstract:Resumo: Objetivou-se, no presente trabalho, a identificação dos principais microrganismos encontrados nas diversas fases de processamento de frangos. Para tal, realizaram-se conta¬gens totais de microrganismos e contagens totais de psicrotróficos da água do escaldador, água de abastecimento, água de “chiller", gelo, aves inteiras após a depenação, aves evisceradas após a passagem pelo "chiller" e antes de serem embaladas. Foram constatadas similaridades entre as contagens totais obtidas e as apresentadas na literatura. O meio de cultura Cristal Violeta Tetrazólio, sugerido para contagens de psicrotróficos, mostrou-se eficaz, na inibição de crescimento de microrganismos Gram positivos. Através de testes morfológicos e bioquímicos realizados nos microrganismos isolados, foram identificadas bactérias dos gêneros: Staphylococcus, Acetobacter, e os psicrotróficos: Achromobacter, Aeromonas e Pseudomonas.Abstract:The objective of the present work was to identify the main contaminant microbial flora found at the different stages of poultry processing. Total counts and psychrotrophic total counts were carried out in the scalding water, washing water, chiller water and slush-ice also in the entire chicken after Defeathering and eviscerated chicken after chilling and before packaging. Similarities were found among the total counts determined and the ones reported in the literature. Crystal Violet Tetrazolium media suggested for psychrotrophic count was efficient to inhibit growth of Gram positive organisms. The isolated organisms were examined by biochemical and morphological tests, and microorganisms of the genus Staphylococcus, Acetobacter and the psychrotrophic Achromobacter, Aeromonas and Pseudomonas were identified
