Public health concerns associated with high prevalence of foodborne salmonellosis, the emergence of antibiotic-resistant organisms and the identification of poultry meat and products as one of the most common sources of Salmonella support the need for new pathogen control strategies in the poultry industry. Scientific research has focused on the use of bacteriophages as therapeutic agents for humans and animals; however, limited studies have been conducted on bacteriophage application on food safety, especially on poultry. Therefore, the objective of this study was to evaluate the phage density and exposure time required to reduce Salmonella load on experimentally inoculated chicken meat. In Experiment 1, serovars of Salmonella were tested for antimicrobial susceptibility and rifampicin-resistant isolates were generated. Cocktails of the serovars Enteritidis, Kentucky and Typhimurium (EKT), and Hadar and Heidelberg (HH), were inoculated on chicken breast samples to a target of 104 CFU/g. A mixture of three lytic bacteriophages, active against multiple Salmonella serovars was applied to chicken samples. A total of 84 samples (25 +/- 2 g) per each cocktail were distributed among a negative control, Salmonella-inoculated positive control, Salmonella-inoculated samples treated with the phage mixture at differing titers (105, 106, 107, 108, and 109 PFU/ml) with two identical samples at 0, 15, 30, 60, 120, 360 min at 4 degrees C. Experiment 2 evaluated nalidixic acid-resistant Salmonella Typhimurium among negative control, Salmonella-inoculated control (positive control), Salmonella with two phage titers (105 and 109 PFU/ml) at 0, 30, 60 and 120 min at 25 degrees C and 4 degrees C. Results showed differences in means for Salmonella cocktail EKT ranged from 0.1 to 0.7 log10 CFU/g with 0.7 log10 for 108 PFU/ml, 30 min, 4 degrees C. For Salmonella cocktail HH, reductions ranged from 0.1 to 0.4 log10 CFU/g with 0.4 log10 on samples treated with 108 PFU/ml, 120 min, 4 degrees C. For the Experiment 2, a higher phage concentration (109 PFU/ml) at 120 min post-inoculation storage at 25 degrees C was required to yield a 0.9 log10 difference in means. These findings showed that higher concentrations of bacteriophage were more effective controlling Salmonella than lower ones at both temperatures. In addition, temperature, time and bacterial attachment may influence phage efficacy.

The objective of this study was to evaluate the efficacy of buffered vinegar in a marinade solution on inhibiting Listeria monocytogenes growth on cooked broiler breast meat. Broiler breasts were vacuum-tumbled for 30 min in a marinade consisting of dry (0%, 0.4% DV, 0.6%DV, and 0.8%) or liquid vinegar (1.5%), sodium chloride, sodium tripolyphospate, and water. The chicken breasts were then cooked to an internal temperature of 75°C. The breast meat was inoculated with L. monocytogenes, placed into modified atmosphere packaging, and stored at 2°C plus/minus 2 for 0-60 days. L. monocytogenes growth was stable on treatments for up to 30 days. However, from 35 to 60 days, the buffered vinegar treatments had fewer L. monocytogenes counts (P<0.05) than the control treatment. In addition, the 0.8 % DV and 1.5 % LV treatments had fewer than 2.0 log counts of L. monocytogenes after 60 days of storage.

In 2013, the wooden breast defect in broiler breast meat was characterized by hardened and pale areas at both the caudal and cranial regions of the breast. The objective of this study was to determine the flavor differences between severe woody and normal breast meat in both breast and patties using gas chromatography-mass spectrometry, gas chromatography-olfactometry, and sensory descriptive analysis. Forty-eight individual volatile flavor compounds were identified in both the ground and whole breast chicken samples including aldehydes, ketones, and other functional groups. Minimal differences existed in the volatile fraction of normal and severe woody breast meat. In contrast, woody breast patties had greater concentrations of many oxidation products, including aldehydes, alcohols, and hydrocarbons. The most intense aroma compounds were hexanal, 1-octen-3-ol, 2-pentylfuran, 2-ethylhexyl acetate, and 1-nonanol. The descriptive and volatile results indicated that in patties, woody breast meat was more susceptible to oxidation and off-flavors than normal breast meat.

Wooden breast (WB) is a Pectoralis major muscle myopathy in broilers that has negatively impacted breast meat quality and the poultry industry for over five years. The objective of this research was to evaluate quality differences in normal (NOR), moderately woody (MOD), and severely woody (SEV) broiler breast meat marinated with water (control), water, sodium phosphate, and salt (traditional) and water, potassium carbonate and salt (clean label). The second objective of this research was to evaluate quality differences in chicken patties made with varying percentages of NOR to SEV breast meat (0% NOR, 33% NOR, 67% NOR, 100% NOR) and marinades using salt (control), salt and sodium phosphate (traditional), or salt and potassium carbonate (clean label) as functional ingredients in patties. Overall marination did not significantly improve eating quality of WB meat, and no more than 33% of SEV WB meat should be added to any comminuted chicken product.

Made available in DSpace on 2014-06-11T19:27:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-19Bitstream added on 2014-06-13T20:56:44Z : No. of bitstreams: 1 cardoso_kfg_me_botfmvz.pdf: 154354 bytes, checksum: 9792019d2b4a07049f1b55153e0640e4 (MD5) / Estudou-se o efeito da irradiação na redução e/ou destruição de microrganismos presentes em filés de peito de frango armazenados sob refrigeração e congelamento. Foram obtidos 40 filés de peito de frango, provenientes de abatedouro comercial inspecionado pelo SIF. As amostras foram acondicionadas em embalagens plásticas seladas a vácuo, sendo em seguida resfriadas ou submetidas ao congelamento lento. As amostras foram irradiadas com dose de 3 kGy e em seguida armazenadas em câmara frigorífica (4°C) por 21 dias ou freezer (-18°C) por 90 dias, conforme o tratamento. Foram realizadas análises microbiológicas para enumeração de microrganismos mesófilos aeróbios ou anaeróbios facultativos, psicrotróficos, determinação do Número Mais Provável de coliformes totais e termotolerantes e detecção da presença de Salmonella. A dose de 3 kGy foi suficiente para melhorar a qualidade microbiológica dos filés de frango e oferecer maior segurança para o consumidor, quanto à presença de Salmonella. / The effect of irradiation on the reduction and/or destruction of microorganisms present in chicken breast stored under refrigeration and freezing was studied. Forty chicken breast filets were obtained from a slaughterhouse inspected by the SIF. The samples were placed in vacuum plastic packages and then they were refrigerated or submitted to slow freezing. The samples were irradiated with a dose of 3 kGy and then stored in cold room (4°C) for 21 days or freezer (-18°C) for 90 days, according to treatment. Microbiological analyses were performed to determine the number of mesophilic aerobic microorganisms,or optional anaerobic, psychrotrophic, determination of the number of total and thermotolerant coliforms and detection of the presence of Salmonella. The dose of 3 kGy was enough to improve the microbiological quality of the chicken breast and provide more safety to the consumers, regarding the presence of Salmonella.

Orientador: Ariel Antônio Mendes / Banca: Roberto de Oliveira Roça / Banca: Vera Lúcia Moraes Rall / Resumo: Estudou-se o efeito da irradiação na redução e/ou destruição de microrganismos presentes em filés de peito de frango armazenados sob refrigeração e congelamento. Foram obtidos 40 filés de peito de frango, provenientes de abatedouro comercial inspecionado pelo SIF. As amostras foram acondicionadas em embalagens plásticas seladas a vácuo, sendo em seguida resfriadas ou submetidas ao congelamento lento. As amostras foram irradiadas com dose de 3 kGy e em seguida armazenadas em câmara frigorífica (4°C) por 21 dias ou freezer (-18°C) por 90 dias, conforme o tratamento. Foram realizadas análises microbiológicas para enumeração de microrganismos mesófilos aeróbios ou anaeróbios facultativos, psicrotróficos, determinação do Número Mais Provável de coliformes totais e termotolerantes e detecção da presença de Salmonella. A dose de 3 kGy foi suficiente para melhorar a qualidade microbiológica dos filés de frango e oferecer maior segurança para o consumidor, quanto à presença de Salmonella. / Abstract: The effect of irradiation on the reduction and/or destruction of microorganisms present in chicken breast stored under refrigeration and freezing was studied. Forty chicken breast filets were obtained from a slaughterhouse inspected by the SIF. The samples were placed in vacuum plastic packages and then they were refrigerated or submitted to slow freezing. The samples were irradiated with a dose of 3 kGy and then stored in cold room (4°C) for 21 days or freezer (-18°C) for 90 days, according to treatment. Microbiological analyses were performed to determine the number of mesophilic aerobic microorganisms,or optional anaerobic, psychrotrophic, determination of the number of total and thermotolerant coliforms and detection of the presence of Salmonella. The dose of 3 kGy was enough to improve the microbiological quality of the chicken breast and provide more safety to the consumers, regarding the presence of Salmonella. / Mestre

Made available in DSpace on 2015-04-17T14:49:21Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 939298 bytes, checksum: 4db0a28a49a01afe330ae2fff4b91cc0 (MD5) Previous issue date: 2011-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The shelf life of foods is the time allowed for food to be consumed safely on the microbiological aspects, physicochemical and sensory characteristics, and is a determining factor in production logistics, trade and consumption, considered in the cost of the product, especially when it comes to perishable foods, for the presence and growth of micro-organisms during production to consumption are inevitable and their study is essential for the development of conservation technologies as well as determining with regard to the risk which consumers are exposed to. In this work we simulated the conditions of time (fifteen days) and temperature (<2.0 ° C) as indicated by the manufacturer shelf life of the product analyzed and the evaluations performed microbiological and physico-chemical properties during times of 0, 5, 10 and 15 days for raw and under cooling (1.4 ± 0.6 ° C) chicken breast without skin. The samples were analyzed for the presence / absence of the microorganism Salmonella spp., quantification of mesophilic microorganisms, MPN- most probable number for the group of coliform bacteria, the presence / absence of the Escherichia coli and pH analysis. None of the samples showed the presence of Salmonella spp. during the study , however, 10 days time was the limit for guaranteeing the quality of the microorganism Fecal samples at 45 ° C, and 70% of samples unfit for human consumption and at odds with the precepts of sanitary legislation in force. It was found that the microbiological quality of chicken flesh had flaws, as demonstrated by the high number of mesophilic aerobic bacteria, coliforms at 35 ° C and the confirmed presence of E. coli in 20% of the samples, which may therefore be a potential risk for the occurrence of foodborne illnesses DVA. / A vida de prateleira dos alimentos é o tempo estabelecido para que o alimento seja consumido com segurança quanto aos aspectos microbiológicos, físico-químicos e sensoriais, sendo fator determinante na logística de produção, comércio e consumo, sendo considerado no custo do produto, principalmente quando se trata de alimentos perecíveis, pois a presença e o crescimento de micro-organismos durante a produção até o consumo são inevitáveis e seu estudo é essencial para o desenvolvimento de tecnologias de conservação e determinante quanto ao risco em que os consumidores estão expostos. Neste trabalho foram simuladas as condições de tempo (quinze dias) e temperatura (< 2,0°C) indicados pelo fabricante como vida de prateleira do produto analisado e realizadas as avaliações microbiológicas e físicoquímicas durante os tempos de 0, 5, 10 e 15 dias para peito de frango sem pele, cru e sobrefrigeração(1,4 ± 0,6 ºC). As amostras foram analisadas quanto a presença/ausência do microorganismo Salmonella spp., contagem de micro organismos mesófilos, NMP - número mais provável para o grupo de coliformes, presença/ausência de E. coli e análise de pH. Em nenhuma das amostras foi detectada a presença de Salmonella spp., durante o tempo de estudo, porém, o tempo de 10 dias mostrou-se como limite para garantia da qualidade das amostras para o microorganismo Coliformes a 45°C, estando com 70% das amostras impróprias ao consumo humano e em desacordo com o que preceitua a legislação sanitária vigente. Foi possível constatar que a qualidade microbiológica da carne de frango apresentou falhas, como demonstrado pelo elevado número de bactérias aeróbias mesófilas, coliformes a 35°C e confirmação da presença de E. coli em 20% das amostras, podendo, portanto, ser um risco em potencial para ocorrência de Doenças Veiculadas por Alimentos - DVA.

The objective of this study was to evaluate the influence of different ageing time after deboning (deboning time) and ageing time before deboning (holding time) in quality and cook loss of marinated, cooked and frozen chicken breast in continuous process. It was used experimental design 32 (3 deboning time: zero, 6 and 12 hours; and 3 holding time: zero, 12 and 24 hours), total of 9 treatments with 3 cooking repetition, total of 27 experiments. The breast fillets were marinated by tumbling, and brine was formulated with water and sodium chloride. It was evaluated brine absorption, thickness increase and weight loss during cooking, chicken breast pH, sensory analysis, shear force analysis and centesimal analysis of cooked and frozen chicken breast. Deboning time impacted in inicial pH, there was reduction between zero and 6 hours, time where chicken breast achieved rigor mortis resolution. There was an increase in pH with deboning time from 6 to 12 hours. In treatments with zero deboning time, it was observed a decrease in pH from zero to 12 hours, and an increase from 12 to 24 hours. Ageing time didn´t impact in brine absorption during tumbling. Ageing time, before and after deboning, influenced the cook loss, that was lower in fillets aged before deboning comparing to fillets aged after deboning. The increase in holding time from zero to 12 and 24 hours reduced cook loss, despite of deboning time. The influence of ageing on the fiber diameter during cooking was observed by significant increase on the thickness of chicken breast. Ageing times influenced sensory analysis as color, juiciness, flavor and tenderness, it was concluded that 6 hours before deboning were enough to achieve the desired tenderness. There was significant difference in shear force analysis between aged and not aged fillets. The best results for cooking loss and tenderness were achieved with deboning time of 6 or 12 hours, followed by holding time of 24 hours. / O objetivo deste trabalho foi avaliar a influência de diferentes tempos de maturação antes da desossa (tempo de desossa) e tempos de maturação após a desossa (tempos de espera) na qualidade e nas perdas de peso por cozimento do peito de frango marinado, cozido e congelado em processo contínuo. Foi utilizado um planejamento experimental 32 (3 tempos de desossa: zero, 6 e 12 horas; e 3 tempos de espera: zero, 12 e 24 horas), totalizando 9 tratamentos, com 3 repetições de cozimento, totalizando 27 experimentos. Os peitos de frango foram marinados por tambleamento com salmoura formulada com água e cloreto de sódio. Foram realizadas análises de absorção de salmoura, aumento de espessura e perda de peso no cozimento, análises de pH do peito de frango, análise sensorial, análise de força de cisalhamento e análise centesimal do peito de frango após cozimento e congelamento. O tempo de desossa influenciou o pH inicial, havendo redução de pH de zero para 6 horas, onde o peito atingiu a resolução do rigos mortis. O aumento de tempo de desossa de 6 para 12 horas levou a um aumento de pH. Para os tratamentos com tempo de desossa zero, observou-se declínio do pH até 12 horas, com aumento de 12 para 24 horas. Os tempos de maturação não influenciaram a absorção de salmoura do peito de frango durante o tumbleamento. Os tempos de desossa, tempos de espera influenciaram nas perdas de peso por cozimento, ocorrendo menores valores para peitos de frango maturados antes da desossa em relação aos tratamentos maturados após desossa. O aumento do tempo de espera de zero para 12 ou 24 horas reduziu a de perda de peso no cozimento, independente do tempo de desossa. A maturação influenciou no comprimento das fibras durante o cozimento, evidenciado pelo encolhimento e conseqüente aumento de espessura dos peitos de frango. Os tratamentos de maturação influenciaram os atributos de cor, sabor, suculência e maciez. Concluiu-se que 6 horas de maturação antes da desossa são suficientes para atender a maciez desejada. Houve diferença significativa de força de cisalhamento entre os filés não maturados e maturados. Os melhores resultados de perda de cozimento e maciez foram obtidos para maturação antes da desossa por 6 ou 12 horas, seguidos de maturação após desossa por 24 horas.