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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rearing temperature and the meat yield of broilers

Howlider, Abdur Rahman January 1988 (has links)
The objective of this study was to examine the effects of rearing temperature on the meat yield of broilers. Four experiments were conducted. Experiment 1 examined meat yield at different temperatures and on different diets when birds were grown to a fixed age. Experiments 2 and 3 were aimed at the effects of temperature and of the interaction between temperature and stocking density respectively on the meat yield of broilers when killed at a specified liveweight (i.e. allowing the rearing period to vary). Experiment 4 was designed to assess whether depression of growth rate at high temperature affected the meat yield in broilers.
2

The Effect of Hand Catching and Machine Catching Methods on Broiler Breast Meat Quality

Radhakrishnan, Vijayakumar 05 May 2007 (has links)
Mechanical and hand catching of broilers were performed to determine if differences existed in breast meat quality among catching methods. Meat quality results were summarized using a two-prong approach to investigate if average differences existed in meat quality through the determination of ultimate pH, rapid pH decline, color, water holding capacity, and tenderness within each treatment and by pinpointing individual quality problems within treatments. Two trials were conducted and revealed greater variation in meat quality during summer in comparison to winter within treatments in both catching methods. In winter, there was a lower incidence (p<0.05) of paleness in birds that were crated for 2h prior to euthanasia in comparison to birds immediately euthanized after catching within both hand and machine catching methods. Mechanical catching and crating for 2 hours was conducive to slightly better quality meat than hand catching in respect to averages and individual quality problems.
3

Irradiação e qualidade da carne de frango congelada e embalada à vácuo /

Leonel, Fábio Roberto. January 2008 (has links)
Orientador: Hirasilva Borba Alves de Soza / Banca: Vera Fernanda Martins Hossepian de Lima / Banca: Maria Regina Barbieri de Carvalho / Banca: Alexandre Oba / Banca: Ariel Antonio Mendes / Resumo: A busca por alimentos seguros faz da irradiação umas das técnicas de tratamentos de alimentos mais promissoras nos dias atuais, porém, a falta de informações por parte dos consumidores tem sido algo a se destacar. O objetivo do trabalho de pesquisa foi avaliar o efeito da irradiação nas características físicoquímicas, sensoriais e microbiológicas da carne de peito (Pectoralis major) de frangos de corte congelada e armazenada. Foram utilizados 96 bandejas plásticas de polietileno expandido, com aproximadamente 650 gramas de filés por bandeja, das quais 48 bandejas foram recobertas por filme plástico (PVC) e a outra metade (48) foram recobertas por sacolas plásticas e submetidas a vácuo. As bandejas foram submetidas ao congelamento, em túnel por cerca de 9 horas a -36°C e mantidas sob congelamento (-20°C). A irradiação foi realizada em um irradiador comercial de grande porte, por meio de raios gama, provenientes do radioisótopo Cobalto-60 utilizado como fonte, a uma taxa de dose de 4 kGy/h. O delineamento experimental utilizado foi o inteiramente casualizado, com 4 repetições, 24 tratamentos de acordo com um esquema fatorial 2 x 3 x 4, dois tipos de embalagens (filme e vácuo), três doses de radiação (0; 1,5 e 3,0 kGy) e quatro períodos de armazenamento (0, 2, 4 e 6 meses). Os resultados mostram que com a irradiação houve aumentou significativo na oxidação do músculo (TBARS), alterações na cor com aumento na luminosidade e intensidade de vermelho e redução no amarelo. O vácuo promoveu redução nos valores de TBARS, força de cisalhamento,...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The search for safety foods makes the irradiation one of the most promising treatments of food, but a lack of information from consumers is something that has to be seen. The aim of this study was to evaluate the radiation effects on physics, chemicals, sensorial and microbiological characteristics of frozen and stored broiler breast meat (Pectoralis major). It was used 96 plastic trays of expanded polyethylene, with approximately 650 grams of filets (breast meat) per tray, 48 trays were covered with plastic film (PVC) and the other half (48 trays) were covered with plastic bags and submitted to vacuum. The trays with the samples were frozen in freezing tunnels for about 9 hours to -36°C and then maintained under freezing temperatures (-20°C). The radiation was accomplished in a commercial reactor, using high-energy gamma radiation, given off by a radioactive source (radioisotope Cobalt-60 - 4 kGy/h).A completely randomized experimental design was used, in a factorial arrangement 2 x 3 x 4 - 2 packing types (plastic film and vacuum), 3 irradiation levels (0; 1,5 e 3,0 kGy) and 4 storage periods (0, 2, 4 e 6 months).The results showed that meat radiation process took to an oxidation increase (TBARS) and to a color alteration, increasing brightness and red values and decreasing the yellow intensity. Vacuum action reduced the TBARS values, shear force, volume and protein of exudates liquid and weight loss during cooking. Radiation reduced the sensorial characteristics, mainly when the radiation level used was 3,0 kGy. However, the use of vacuum was positive, increasing sensorial parameters. The radiation use was effective in the elimination of fecal/totals coliforms, independently of the storage. / Doutor
4

Irradiação e qualidade da carne de frango congelada e embalada à vácuo

Leonel, Fábio Roberto [UNESP] 22 February 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-02-22Bitstream added on 2014-06-13T20:25:11Z : No. of bitstreams: 1 leonel_fr_dr_jabo.pdf: 842838 bytes, checksum: 7e58ff8a68976255ea5f2cb9969dcd21 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A busca por alimentos seguros faz da irradiação umas das técnicas de tratamentos de alimentos mais promissoras nos dias atuais, porém, a falta de informações por parte dos consumidores tem sido algo a se destacar. O objetivo do trabalho de pesquisa foi avaliar o efeito da irradiação nas características físicoquímicas, sensoriais e microbiológicas da carne de peito (Pectoralis major) de frangos de corte congelada e armazenada. Foram utilizados 96 bandejas plásticas de polietileno expandido, com aproximadamente 650 gramas de filés por bandeja, das quais 48 bandejas foram recobertas por filme plástico (PVC) e a outra metade (48) foram recobertas por sacolas plásticas e submetidas a vácuo. As bandejas foram submetidas ao congelamento, em túnel por cerca de 9 horas a -36°C e mantidas sob congelamento (-20°C). A irradiação foi realizada em um irradiador comercial de grande porte, por meio de raios gama, provenientes do radioisótopo Cobalto-60 utilizado como fonte, a uma taxa de dose de 4 kGy/h. O delineamento experimental utilizado foi o inteiramente casualizado, com 4 repetições, 24 tratamentos de acordo com um esquema fatorial 2 x 3 x 4, dois tipos de embalagens (filme e vácuo), três doses de radiação (0; 1,5 e 3,0 kGy) e quatro períodos de armazenamento (0, 2, 4 e 6 meses). Os resultados mostram que com a irradiação houve aumentou significativo na oxidação do músculo (TBARS), alterações na cor com aumento na luminosidade e intensidade de vermelho e redução no amarelo. O vácuo promoveu redução nos valores de TBARS, força de cisalhamento,... / The search for safety foods makes the irradiation one of the most promising treatments of food, but a lack of information from consumers is something that has to be seen. The aim of this study was to evaluate the radiation effects on physics, chemicals, sensorial and microbiological characteristics of frozen and stored broiler breast meat (Pectoralis major). It was used 96 plastic trays of expanded polyethylene, with approximately 650 grams of filets (breast meat) per tray, 48 trays were covered with plastic film (PVC) and the other half (48 trays) were covered with plastic bags and submitted to vacuum. The trays with the samples were frozen in freezing tunnels for about 9 hours to -36°C and then maintained under freezing temperatures (-20°C). The radiation was accomplished in a commercial reactor, using high-energy gamma radiation, given off by a radioactive source (radioisotope Cobalt-60 - 4 kGy/h).A completely randomized experimental design was used, in a factorial arrangement 2 x 3 x 4 - 2 packing types (plastic film and vacuum), 3 irradiation levels (0; 1,5 e 3,0 kGy) and 4 storage periods (0, 2, 4 e 6 months).The results showed that meat radiation process took to an oxidation increase (TBARS) and to a color alteration, increasing brightness and red values and decreasing the yellow intensity. Vacuum action reduced the TBARS values, shear force, volume and protein of exudates liquid and weight loss during cooking. Radiation reduced the sensorial characteristics, mainly when the radiation level used was 3,0 kGy. However, the use of vacuum was positive, increasing sensorial parameters. The radiation use was effective in the elimination of fecal/totals coliforms, independently of the storage.
5

The Effects of Low Atmospheric Pressure and Electrical Stunning on the Instrumental and Sensory Quality of Broiler Breast Meat Deboned at 45 Minutes and 4 Hours Postmortem

Radhakrishnan, Vijayakumar 14 December 2013 (has links)
Low Atmospheric Pressure Stunning (LAPS) has recently become available to the broiler industry. Therefore, research was conducted to determine the effect of stunning method (LAPS and Electrical Stunning(ES)) and postmortem deboning time (0.75 hr and 4 hr) on the instrumental and sensory acceptability (3 replications) of breast meat (n=576, 144 birds per treatment) prepared using different cooking methods (fried, baked, sous vide). Breast meat was evaluated for pH, CIE L*a*b*, yields, shear force, and consumer acceptability. Postmortem pH decline was more rapid (P<0.05) in the breast meat of LAPS stunned birds when compared to ES stunned birds, but no differences existed (P>0.05) among treatments with respect to final pH. On average, no differences (P > 0.05) existed in the sensory acceptability of fried and sous vide cooked broiler breast treatments. However, for the baked cooking method, the LAPS treatment that was deboned at 4 hr was more acceptable (P<0.05) than other treatments and the ES and LAPS 4 hr postmortem treatments had more acceptable (P<0.05) texture than the ES and LAPS 0.75 hr treatments. Since consumers were highly variable in their liking of chicken breast treatments, consumers were grouped into 6 clusters for each cooking method based on liking and preference. Cluster analysis data revealed that the greatest number of consumers liked all chicken breast treatments, but a larger proportion of consumers liked the 4 hour LAPS and ES treatments when compared to the 0.75 hr LAPS and ES treatments for all cooking methods. In addition, the consumers that indicated that baked chicken breast was highly acceptable preferred (P<0.05) breast meat from the 4 hr LAPS treatment over chicken breast meat from the 4 hr ES treatment. Based on sensory results, chicken breast meat from all stunning and deboning method combinations was highly acceptable to the majority of consumers, but the LAPS 4 hr treatment was slightly more acceptable than other treatments when baked.
6

Controle de Salmonella sp. em carcaças de frango pelo uso de descontaminantes químicos durante o processo de abate e as consequências na qualidade da carne /

Nicolau, Juliana Pampana. January 2016 (has links)
Orientador: Elisa Helena Giglio Ponsano / Coorientador: Marcos Franke Pinto / Banca: Maria Luiza Poiatti / Banca:Andréa Fontes Garcia / Banca: Flavia Lombardi Lopes / Banca:Marcelo Vasconcelos Meireles / Resumo: O Brasil é um grande produtor e exportador de carne de frango e, por isso, deve primar em fornecer o produto com segurança e qualidade. A Salmonella sp. destaca-se dentre os patógenos que podem contaminar a carne de frango e, para minimizar sua prevalência, a legislação brasileira permite o uso de até 5 ppm de hipoclorito de sódio no pré-resfriamento de carcaças de frango, enquanto que outros países preconizam o uso de ozônio e ácido láctico para a mesma finalidade. Este estudo objetivou verificar se diferentes concentrações de hipoclorito de sódio, ozônio e ácido láctico, utilizados isoladamente e em conjunto na descontaminação de carcaças de frango, são eficazes na eliminação desse patógeno e se provocam alterações em suas características de qualidade. Para pesquisar a eliminação da Salmonella sp., carcaças foram contaminadas com Salmonella Enteritidis e, em seguida, submetidas aos tratamentos com os sanitizantes. Para a pesquisa sobre as características da carne, as carcaças foram tratadas com os sanitizantes e analisadas quanto a pH, rancidez, cor e sabor. O hipoclorito de sódio foi o sanitizante mais eficiente para a descontaminação das carcaças e, também, o que mais provocou alterações nas características da carne, como a redução do pH e da rancidez e o aumento da luminosidade. Na análise sensorial, não se encontrou diferença entre os tratamentos com os diferentes sanitizantes. Concluiu-se que o uso isolado do hipoclorito de sódio na concentração máxima permitida no Bra... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Brazil is a major producer and exporter of poultry meat and must aim to provide the product with safety and quality. Salmonella sp. is among the pathogens that can contaminate poultry meat and, to minimize its prevalence, Brazilian laws allow the use of up to 5 ppm of sodium hypochlorite in the precooling of poultry carcasses while other countries recommend the use of ozone and lactic acid. This study aimed to investigate if sodium hypochlorite, ozone and lactic acid used in different concentrations for the decontamination of broilers carcasses, alone or in combination, are effective for eliminating this pathogen and if their use may change the quality characteristics of broiler meat. To investigate the elimination of Salmonella sp., the carcasses were contaminated with Salmonella Enteritidis and then treated with the sanitizers. For the evaluation of the meat characteristics, carcasses were treated with the sanitizers and analyzed for pH, rancidity, color and flavor. Sodium hypochlorite was the most efficient sanitizer for the decontamination of the carcasses and also the one which caused most changes in meat characteristics, such as lowering pH and rancidity and increasing lightness. Sensory analysis showed no difference among treatments. In conclusion, the use of sodium hypochlorite alone at the maximum allowable concentration in Brazil was enough to eliminate the pathogen, not requiring the use of any other sanitizers for the same purpose, and the changes it caused to mea... (Complete abstract click electronic access below) / Doutor
7

Controle de Salmonella sp. em carcaças de frango pelo uso de descontaminantes químicos durante o processo de abate e as consequências na qualidade da carne / Control of Salmonella spp. in poultry carcasses by using chemical decontaminants during slaughter and the consequences for the meat quality

Nicolau, Juliana Pampana [UNESP] 28 June 2016 (has links)
Submitted by Juliana Pampana Nicolau null (julianapampana@yahoo.com.br) on 2016-07-12T14:52:49Z No. of bitstreams: 1 Tese Doutorado Juliana Pampana Nicolau.pdf: 1262579 bytes, checksum: d130f3374dbb5a40ecba494efb96532e (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-07-14T20:16:55Z (GMT) No. of bitstreams: 1 nicolau_jp_dr_araca.pdf: 1262579 bytes, checksum: d130f3374dbb5a40ecba494efb96532e (MD5) / Made available in DSpace on 2016-07-14T20:16:55Z (GMT). No. of bitstreams: 1 nicolau_jp_dr_araca.pdf: 1262579 bytes, checksum: d130f3374dbb5a40ecba494efb96532e (MD5) Previous issue date: 2016-06-28 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O Brasil é um grande produtor e exportador de carne de frango e, por isso, deve primar em fornecer o produto com segurança e qualidade. A Salmonella sp. destaca-se dentre os patógenos que podem contaminar a carne de frango e, para minimizar sua prevalência, a legislação brasileira permite o uso de até 5 ppm de hipoclorito de sódio no pré-resfriamento de carcaças de frango, enquanto que outros países preconizam o uso de ozônio e ácido láctico para a mesma finalidade. Este estudo objetivou verificar se diferentes concentrações de hipoclorito de sódio, ozônio e ácido láctico, utilizados isoladamente e em conjunto na descontaminação de carcaças de frango, são eficazes na eliminação desse patógeno e se provocam alterações em suas características de qualidade. Para pesquisar a eliminação da Salmonella sp., carcaças foram contaminadas com Salmonella Enteritidis e, em seguida, submetidas aos tratamentos com os sanitizantes. Para a pesquisa sobre as características da carne, as carcaças foram tratadas com os sanitizantes e analisadas quanto a pH, rancidez, cor e sabor. O hipoclorito de sódio foi o sanitizante mais eficiente para a descontaminação das carcaças e, também, o que mais provocou alterações nas características da carne, como a redução do pH e da rancidez e o aumento da luminosidade. Na análise sensorial, não se encontrou diferença entre os tratamentos com os diferentes sanitizantes. Concluiu-se que o uso isolado do hipoclorito de sódio na concentração máxima permitida no Brasil é suficiente para a eliminação do patógeno, não sendo necessária a utilização de outros sanitizantes para o mesmo fim, e que as alterações por ele provocadas não afetaram a aceitabilidade do produto. / Brazil is a major producer and exporter of poultry meat and must aim to provide the product with safety and quality. Salmonella sp. is among the pathogens that can contaminate poultry meat and, to minimize its prevalence, Brazilian laws allow the use of up to 5 ppm of sodium hypochlorite in the precooling of poultry carcasses while other countries recommend the use of ozone and lactic acid. This study aimed to investigate if sodium hypochlorite, ozone and lactic acid used in different concentrations for the decontamination of broilers carcasses, alone or in combination, are effective for eliminating this pathogen and if their use may change the quality characteristics of broiler meat. To investigate the elimination of Salmonella sp., the carcasses were contaminated with Salmonella Enteritidis and then treated with the sanitizers. For the evaluation of the meat characteristics, carcasses were treated with the sanitizers and analyzed for pH, rancidity, color and flavor. Sodium hypochlorite was the most efficient sanitizer for the decontamination of the carcasses and also the one which caused most changes in meat characteristics, such as lowering pH and rancidity and increasing lightness. Sensory analysis showed no difference among treatments. In conclusion, the use of sodium hypochlorite alone at the maximum allowable concentration in Brazil was enough to eliminate the pathogen, not requiring the use of any other sanitizers for the same purpose, and the changes it caused to meat characteristics did not affect the acceptability of the product. / FAPESP: 2013/22340-8
8

Impactos das medidas técnicas e sanitárias nas exportações brasileiras de carne de frango / Impact of sanitary and technical measures in Brazilian exports of poultry meat

Fassarella, Luiza Meneguelli 20 January 2011 (has links)
O principal objetivo deste trabalho é avaliar os efeitos das medidas técnicas e sanitárias introduzidas pelos principais importadores mundiais sobre o acesso da carne de frango brasileira no mercado internacional. O estudo associa a análise de inventário com procedimentos econométricos para mensurar o impacto das medidas técnicas e sanitárias sobre as exportações brasileiras de carne de frango. O impacto das medidas é estimado utilizando um modelo gravitacional construído com dados desagregados do comércio bilateral de carne de frango entre Brasil e seus principais parceiros comerciais para o período de 1996 a 2009. O modelo gravitacional é estimado através do modelo de efeitos fixos e os resultados indicam que o impacto das medidas TBT e SPS é ambíguo sobre as exportações brasileiras de carne de frango. Os resultados indicaram que a existência de regulamentos técnicos e sanitários relacionados à rotulagem pode estar estimulando o comércio desse produto, enquanto que a presença de exigências TBT e SPS que envolvem conformidade parece reduzir o volume das exportações brasileiras de carne de frango. Adicionalmente, a presença das medidas técnicas e sanitárias de natureza proibitiva/quarentenária pode ter impactado positivamente sobre o volume das exportações brasileiras de carne de frango. Trata-se de um resultado relevante por indicar a importância de se considerar as diferentes características e conteúdo dos regulamentos para analisar os impactos das medidas TBT e SPS sobre o comércio. / The major objective of this work is to evaluate the effects of technical and sanitary measures introduced by the main world importers upon Brazilian poultry meat in the international market. The study associates the inventory analysis with econometric procedures to measure the impact of technical and sanitary measures upon Brazilian poultry meat exports. The impact of the measures is estimated using a gravity model constructed with disaggregated data about bilateral poultry meat between Brazil and its major trade partners for the period from 1996 to 2009. The gravity model is estimated with a fixed effects model and the results indicate that the impact of TBT and SPS measures upon Brazilian poultry meat exports is ambiguous. The results indicated that the existence of technical and sanitary regulations related to labeling might be stimulating trade of this product, while the presence of TBT and SPS regulations related to compliance appears to reduce the volume of Brazilian exports of poultry meat. In addition, the existence of prohibitive (and/or subject to quarantine) technical and sanitary measures may present a positive impact upon the traded volume of Brazilian exports of poultry meat. This result is relevant since it indicates the importance in considering different characteristics and content of regulations to analyze the impacts of TBT and SPS measures upon trade.
9

Impactos das medidas técnicas e sanitárias nas exportações brasileiras de carne de frango / Impact of sanitary and technical measures in Brazilian exports of poultry meat

Luiza Meneguelli Fassarella 20 January 2011 (has links)
O principal objetivo deste trabalho é avaliar os efeitos das medidas técnicas e sanitárias introduzidas pelos principais importadores mundiais sobre o acesso da carne de frango brasileira no mercado internacional. O estudo associa a análise de inventário com procedimentos econométricos para mensurar o impacto das medidas técnicas e sanitárias sobre as exportações brasileiras de carne de frango. O impacto das medidas é estimado utilizando um modelo gravitacional construído com dados desagregados do comércio bilateral de carne de frango entre Brasil e seus principais parceiros comerciais para o período de 1996 a 2009. O modelo gravitacional é estimado através do modelo de efeitos fixos e os resultados indicam que o impacto das medidas TBT e SPS é ambíguo sobre as exportações brasileiras de carne de frango. Os resultados indicaram que a existência de regulamentos técnicos e sanitários relacionados à rotulagem pode estar estimulando o comércio desse produto, enquanto que a presença de exigências TBT e SPS que envolvem conformidade parece reduzir o volume das exportações brasileiras de carne de frango. Adicionalmente, a presença das medidas técnicas e sanitárias de natureza proibitiva/quarentenária pode ter impactado positivamente sobre o volume das exportações brasileiras de carne de frango. Trata-se de um resultado relevante por indicar a importância de se considerar as diferentes características e conteúdo dos regulamentos para analisar os impactos das medidas TBT e SPS sobre o comércio. / The major objective of this work is to evaluate the effects of technical and sanitary measures introduced by the main world importers upon Brazilian poultry meat in the international market. The study associates the inventory analysis with econometric procedures to measure the impact of technical and sanitary measures upon Brazilian poultry meat exports. The impact of the measures is estimated using a gravity model constructed with disaggregated data about bilateral poultry meat between Brazil and its major trade partners for the period from 1996 to 2009. The gravity model is estimated with a fixed effects model and the results indicate that the impact of TBT and SPS measures upon Brazilian poultry meat exports is ambiguous. The results indicated that the existence of technical and sanitary regulations related to labeling might be stimulating trade of this product, while the presence of TBT and SPS regulations related to compliance appears to reduce the volume of Brazilian exports of poultry meat. In addition, the existence of prohibitive (and/or subject to quarantine) technical and sanitary measures may present a positive impact upon the traded volume of Brazilian exports of poultry meat. This result is relevant since it indicates the importance in considering different characteristics and content of regulations to analyze the impacts of TBT and SPS measures upon trade.
10

Efeito das variações térmicas na perda de umidade em carcaças de frango / Effect of thermal variation on the moisture loss in broiler carcasses

Franco, Fábio de Oliveira 24 August 2007 (has links)
O presente trabalho objetivou estudar o impacto das variações térmicas durante o armazenamento de carcaças de frango sobre as propriedades funcionais, especialmente a perda de umidade no descongelamento (Drip Loss). Para avaliação destas condições, foram simuladas duas situações: uma comercial, onde um lote de aves abatidas, evisceradas e resfriadas em chiller foram congeladas até -15 (±2)°C e sofreram variações térmicas em ciclos de 8 horas com retirada das mesmas da câmara de estocagem, passando de -15 (±2)°C a -3(±2)°C, momento em que eram novamente devolvidas a câmara de congelamento (situação crítica) e outro lote mantido congelado a -15(±2)°C (situação ideal). Outra condição, chamada de ensaio modelo, foram simuladas 7 faixas de temperatura de armazenamento (0°C, -3°C, -6°C, -9°C, -12°C, -15°C e -18°C) visando definir faixas críticas, baseadas em valores de Drip Loss. Foram definidas 2 faixas: -3°C e -6°C, baseadas em sua proximidade a faixa mais crítica e com valores maiores de Drip Loss (0°C). Para estudo das propriedades funcionais no ensaio comercial, amostra (n=120) de carcaças, divididas em situação ideal (n=60) e situação crítica (n=60) foram descongeladas e submetidas às análises de pH, cor e perda de umidade por descongelamento (Drip Test). Os resultados encontrados mostraram uma tendência (p<0,05) de aumento do Drip Loss com o aumento do tempo de armazenamento na situação crítica, com valores de 4,77(±1,24)% para 3 dias e 10,28(±0,87)% para 120 dias. A situação ideal não apresentou diferenças significativas entre os resultados encontrados, que foram de 5,19(±1,13)% para 3 dias e 4,86(±0,84)% para 120 dias. Para estudo das propriedades funcionais no ensaio modelo, amostras (n=70), em triplicata, de carcaças foram descongeladas e, após a definição das faixas críticas, submetidas às análises de perda umidade por descongelamento (Drip Test), capacidade de retenção de água, análise de perda de umidade no cozimento, quantificação do gel protéico, análise do teor de proteínas no exsudato, análise do perfil protéico do exsudato e análise histológica. Os resultados demonstraram não haver diferenças estatísticas (p<0,05) entre as faixas críticas estudadas (-3°C e -6°C) em relação às propriedades funcionais, com exceção das análises de perda de umidade por descongelamento (Drip Test), onde a mesma tendência de aumento do Drip Loss em relação ao tempo de armazenamento foi encontrada, com valores de 5,85 (±1,16)% para 0 dia e 12,33 (±1,12)% para 70 dias na faixa -3°C e 5,83 (±1,93)% para 0 dia e 10,15 (±0,15)% para 70 dias na faixa -6°C. Concluindo, existem evidências de que as variações térmicas promovem o aumento do Drip Loss em relação a um maior tempo de armazenamento. A constatação deste fato serve como base para estudos mais aprofundados sobre o impacto das condições de armazenamento sobre as propriedades funcionais da carne de frango, bem como para padronizar os processos de congelamento, transporte, distribuição e venda de carne de frango congelada. / The objective of this work was to study the impact of thermal variations during the storage of broiler carcasses on its functional properties, especially the moisture loss during thawing (Drip Loss). In order to evaluate these conditions, two situations were simulated: one called commercial, where a batch of slaughtered, eviscerated and chilled on water system broilers were frozen to -15(±2)°C and divided in two equal batches: one of these batches was called Critical Condition and was maintained in a 8 hour cycle of thermal variation ranging from -15(±2)°C to -3(±2)°C while the other, called Ideal Condition was maintained at -15(±2)°C during all the storage time. In another situation, named Model, seven ranges of storage temperature (0±2°C, -3±2°C, -6±2°C, -9±2°C, -12±2°C, -15±2°C , -18±2°C) were simulated in order to obtain the critical ranges based on the Drip Loss values. Two ranges were found based on its proximity to the most critical range and bigger Drip Loss values: -3±2°C and -6±2°C. For the functional properties studies on the commercial situation, a sample (n=120) of broiler carcasses, equally divided in Critical and Ideal were unfrozen and pH, color and Drip Loss analyzed. The results showed a statistical trend (p<0,05) of increase of Drip Loss values as time of storage increases in the critical condition, with values of 4,77±1,24% for 3 days of storage and 10,28±0,87% for 120 days of storage. The ideal condition didnt showed significant differences among the obtained results that were from 5,19±1,13% for 3 days of storage to 4,86±0,84% for 120 days. For the functional properties studies on the model situation, a sample (n=70), in triplicate, of broiler carcasses was thawed and, after the definition of the critical ranges, it was analyzed for Drip Loss, water holding capacity, moisture loss during cooking, Exudative cooking gel quantification, protein quantification on the exsudate, protein profile on the exudate and histological evaluation. The results showed that there were no statistical differences (p<0,05) between the studied critical ranges (-3±2°C and -6±2°C) in relation to its functional properties, except for Drip Loss values, where a trend of increase in Drip Loss as the time of storage increases was found, with values from 5,85±1,16% for 0 days to 12,33±1,12% for 70 days in range -3±2°C and from 5,83±1,93% for 0 days to 10,15±0,15% for 70 days in range -6±2°C. In conclusion, theres some evidence that the thermal variation can cause the increase of Drip Loss values in relation to an increase of the storage time. All these data can be useful as basis for new studies on functional properties of broiler meat regard to thermal variation during storage, as well as, to standard the processes of freezing, transport, distribution, and retail of frozen broiler meat.

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