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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.
21

An analysis of temperature breaks in the summer fruit export cold chain from pack house to vessel

Haasbroek, Laura Marchand 12 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: There is great concern in the fruit industry that too much fruit and money is lost each year due to breaks occurring in the export cold chain of fresh fruit. Therefore, the CSIR (Council for Scientific and Industrial Research) and Stellenbosch University were approached to do research on this problem. This particular study focuses on the cold chains of table grapes, summer pears and plums as these fruit are especially sensitive to temperature. Observations were made on fruit farms, in pack houses, in cold stores as well as in the Port of Cape Town. From these observations it was clear that protocols are not always followed and fruit quality is sometimes neglected because of pressure to speed up the exporting process. In order to analyse the export cold chains of these fruit types, temperature trials were conducted and temperature data received from exporting companies was analysed. The data was analysed from the cold store up to the point where the vessel sailed out of the Port of Cape Town. From the analysis it became clear that too many cold chain breaks occur during fruit exports from South Africa, especially during the loading of containers at cold stores. As a final output to the study, a good cold chain practice guide for the export of table grapes was developed with the aim of assisting the fruit industry in minimizing these cold chain breaks. The guide was developed with simplicity to ensure easy understanding under all role-players in the industry. This study was a small step in the right direction, but it should be highlighted that the complexity of the problems in the fruit cold chains are substantial and further research will have to be done in order to eliminate the occurrence of these cold chain breaks.
22

Estudo da qualdiade microbiolÃgica, quÃmica, fÃsico-quÃmica e sensorial de cenoura (Daucus carot, L.) submetida à tecnologia Sous vide produzida em escala industrial / Study of quality microbiological, phisical-chemical, chemical and sensory carrot (Daucus carot .L) submitted to sous vide produced industially technology.

Ticiane Coelho Abreu de Oliveira 28 August 2012 (has links)
The carrot is a crop rich in carotenoids, pro-vitamin A, minerals and carbohydrates, and is a food with high nutritional value. Brazil is among the five largest producers and consumers of carrot (Daucus carot L .) in the world, concentrating its production in the Southeast. In search of products more attractive, practical, nutritious and healt hy, the consumer's sous vide technology is an alternative technology for the industry in providing food ready for consumption. The sous vide consists in cooking food packaged in plastic vacuum -sealed, subjected to temperatures lower than 100ÂC for extended periods of time, chilled quickly and stored under refrigeration. The aim of this study was to evaluate the quality and shelf life of carrots ( Daucus carot L.) diced submitted to sous vide technology, produced on an industrial scale. The samples were subje cted to physical and chemical analysis and chemical, microbiological and with three replications, with five repetitions of the products, and soon after processing by 2, 4, 6 and 8 weeks of storage (3ÂC). Sensory analysis was carried out on days 0 and 4 weeks, with a repeat. The results indicated a significant difference of 5% (p ≤0.05) in carbohydrate, protein, ash, titratable acidity and chromaticity between the carrot fresh carrot and processed by sous vide technology at time 0. In times of 2, 4, 6 and 8 weeks of storage at 3ÂC difference was significant (p ≤ 0.05) only for protein and total acidity. In sensory analysis, no significant difference (p ≤ 0.05) in any of the attributes studied. It was also observed that the technology sous vide was effective in eliminating vegetative cells of micro-organisms pathogenic and spoilage, yet not been able to eliminate spores. The carrot processed by sous vide technology retains its nutritional characteristics, sensory, chemical and microbiologically stable for up to eight weeks of storage at 3ÂC. / A cenoura à uma olerÃcola rica em carotenÃides, prÃ-vitamina A, minerais e carboidratos, constituindo um alimento com alto valor nutritivo. O Brasil està entre os cinco maiores produtores e consumidores de cenoura (Daucus carot L.) do mundo, concentrando sua produÃÃo na regiÃo sudeste. Na busca de produtos mais atrativos, prÃticos, nutritivos e saudÃveis pelo consumidor, a tecnologia sous vide surge como uma alternativa tecnolÃgica para a indÃstria no fornecimento de pratos prontos para consumo. O sous vide consiste em cozinhar alimentos acondicionados em embalagens plÃsticas seladas à vÃcuo, submetidos a temperaturas inferiores à 100ÂC por longos perÃodos de tempo, resfriados rapidamente e armazenados sob refrigeraÃÃo. O objetivo desse trabalho foi avaliar a qualidade e a vida de prateleira de cenouras (Daucus carot L.) cortadas em cubos submetida a tecnologia sous vide, produzida em escala industrial. As amostras foram submetidas as anÃlises fÃsico-quÃmicas e quÃmicas, com trÃs repetiÃÃes e microbiolÃgicas, com cinco repetiÃÃes, dos produtos, logo apÃs o tecnologia e por 2, 4, 6 e 8 semanas de armazenamento refrigerado (3ÂC). A anÃlise sensorial foi realizada nos tempos de 0 e 4 semanas, com uma repetiÃÃo. Os resultados indicaram que houve diferenÃa significativa de 5% (p≤0,05) nos carboidratos, proteÃnas, cinzas, acidez total titulÃvel e na cromaticidade entre a cenoura in natura e a cenoura processada por tecnologia sous vide no tempo 0. Nos tempos de 2, 4, 6 e 8 semanas de armazenamento a 3ÂC houve diferenÃa significativa (p≤0,05) apenas nas proteÃnas e acidez total titulÃvel. Na anÃlise sensorial, nÃo houve diferenÃa significativa (p≤0,05) em nenhum dos atributos estudado. Observou-se tambÃm que a tecnologia sous vide foi eficiente na eliminaÃÃo de cÃlulas vegetativas de micro-organismos deteriorantes e patogÃnicos, porÃm nÃo foi capaz de eliminar esporos. A cenoura processada por tecnologia sous vide conservou suas caracterÃsticas nutricionais, sensoriais, quÃmicas e manteve-se estÃvel microbiologicamente atà oito semanas de armazenamento à 3ÂC.
23

Caracterización físico-química del membrillo japonés (Chaenomeles Sp. Lindl,). Desarrollo fisiológico y conservación frigorífica

Vila López, Mª Rosario 10 October 2006 (has links)
El género Chaenomeles presenta una especial atención como potencial especie a cultivar y desarrollar en los países del Norte de Europa debido al alto rendimiento en frutos, que a su vez son ricos en zumo, aromas y fibra dietética. La propagación de plantas, es caro y largo en el tiempo, por lo interesa, antes de empezar a hacerlo, estimar el potencial de esta nueva cosecha, comprobar que producirá beneficios. Para esto es necesario un conocimiento profundo de la especie, de su respuesta a factores como son la climatología y edafología, obtener datos de rendimientos, composición, etc.Por ello, entre los objetivos perseguidos con este trabajo están la caracterización físico-química y bioquímica completa del fruto y su zumo, y el estudio de su comportamiento durante el desarrollo fisiológico y durante el almacenamiento. También se busca el conocimiento del efecto de la zona de cultivo en la composición y evolución del fruto. / Chaenomeles genus shows a special attention as a potential fruit to be cultivated and developed in the Northern European countries. It´s due to its very high yield of fruits, which are, besides, very rich in juice, aromas and dietetic fibber. Plant propagation, is expensive and it takes a while, so it is very interesting to prove -before the investment- its potential and that it will make a profit. To get this it´s previously necessary to know deeply the specie, its results to a number of factors like the climate, the edafology, to know its composition.Because of this, the aims of this work are the whole physic-chemical characterization of the fruit, the study of the evolution of the fruit along its physiologycal development and along its storage. It´s also important to know the effect -over the composition and over the evolution of the fruit-, of the cultive area.
24

Numerical modeling and simulation for analysis of convective heat and mass transfer in cryogenic liquid storage and HVAC&R applications

Ho, Son Hong 01 June 2007 (has links)
This work presents the use of numerical modeling and simulation for the analysis of transport phenomena in engineering systems including zero boil-off (ZBO) cryogenic storage tanks for liquid hydrogen, refrigerated warehouses, and human-occupied air-conditioned spaces. Seven problems of medium large spaces in these fields are presented. Numerical models were developed and used for the simulation of fluid flow and heat and mass transfer for these problems. Governing equations representing the conservation of mass, momentum, and energy were solved numerically resulting in the solution of velocity, pressure, temperature, and species concentration(s). Numerical solutions were presented as 2-D and 3-D plots that provide more insightful understanding of the relevant transport phenomena. Parametric studies on geometric dimensions and/or boundary conditions were carried out. Four designs of ZBO cryogenic liquid hydrogen storage tank were studied for their thermal performance under heat leak from the surroundings. Steady state analyses show that higher flow rate of forced fluid flow yields lower maximum fluid temperature. 3-D simulation provides the visualization of the complex structures of the 3-D distributions of the fluid velocity and temperature. Transient analysis results in the patterns of fluid velocity and temperature for various stages of a proposed cooling cycle and the prediction of its effective operating term. A typical refrigerated warehouse with a set of ceiling type cooling units were modeled and simulated with both 2-D and 3-D models. It was found that if the cooling units are closer to the stacks of stored packages, lower and more uniform temperature distribution can be achieved. The enhancement of thermal comfort in an air-conditioned residential room by using a ceiling fan was studied and quantified to show that thermal comfort at higher temperature can be improved with the use of ceiling fan. A 3-D model was used for an analysis of thermal comfort and contaminant removal in a hospital operating room. It was found that if the wall supply grilles are closer to the center, the system has better performance in both contaminant removal and thermal comfort. A practical guideline for using CFD modeling in indoor spaces with an effective meshing approach is also proposed.
25

Análisis y evaluación de factores que determinan el desarrollo del servicio de transporte en frío de productos alimenticios perecederos en un operador logístico

Ocampo Chuquipul, Karla Dalila, Zevallos Romero, Katherine Luz Del Pilar January 2015 (has links)
La presente tesis tiene como propósito principal elaborar un análisis y evaluación de los factores más importantes que determinan el desarrollo del servicio de transporte de productos alimenticios perecederos en un operador logístico en la cadena de frío, en función a las necesidades del cliente y al correcto funcionamiento del servicio; con la finalidad de que la empresa se consolide como operador logístico, brindando los servicios de almacenamiento, consolidación de mercadería, transporte y distribución. A partir de una entrevista con el gerente general y el coordinador de transporte se pudo comprender el origen de diversos problemas que vienen afectando al servicio de transporte, siendo este la falta de un análisis de factores que intervienen en la operatividad del servicio. Antes del análisis de dichos factores, se realizó una revisión bibliográfica de los antecedentes y las bases teóricas referentes al tema. A partir de ello se concluyó que existen muy pocos antecedentes en el Perú de estudios referentes al servicio de transporte de productos alimenticios perecederos y de la cadena de frío. Sin embargo, se encontraron estudios referentes a la cadena de frío en países como Venezuela, Colombia, Estados Unidos y otros países, lo cual nos dio a entender que la gestión de la cadena frío se encuentra más desarrollada en el extranjero. En base a esto, se elaboraron propuestas de mejora con las bases teóricas revisadas, registros de información brindados por la empresa e información adicional recopilada de los clientes. This thesis has as a main purpose preparing an analysis and evaluation of the most important factors determining the development of the service of transporting perishable foodstuffs into a logistics operator in a cold chain, according to the needs of the client and the proper functioning of the operations of the system; the company will obtain a strong base in the branch of the logistics department, providing storage services, consolidation of goods, transport and distribution. From an interview with the general manager and the transportation coordinator, it can be understood that the lack of an analysis in the logistics department is the origin of the diverse problems that are affecting the transport service. Before the analysis of these factors, a literature review of the history and theoretical basis concerning the issue was made. From this it was concluded, that there are very few precedents in Peru, relating to the studies of the transportation of perishable food products and cold chain. However, studies on the operational refrigeration in countries such as Venezuela, Colombia, United States and other countries, gave us information to understand that the management of the cold chain is more developed abroad. Based on the studies made proposals to improve the theoretical foundations were revised, and records of information were provided to develop the logistics process in Peru.
26

Comparative Stability of Compounded Omeprazole Suspension Versus Commercial Omeprazole Kit When Stored in Oral Syringes Under Refrigerated Conditions

Jackson, Remonica, Lewis, Paul, Brown, Stacy D. 01 October 2020 (has links)
Background: Omeprazole is a proton pump inhibitor used to manage gastrointestinal disorders. Special populations may require omeprazole to be given as an oral suspension. Objective: The purpose of this project was to compare the stability of omeprazole in the FIRST kit product to a traditionally compounded omeprazole suspension, when stored in refrigerated unit-dosed syringes. NG tube delivery of the 2 products was also investigated. Methods: Five batches of compounded omeprazole oral suspension and 5 kits of FIRST-Omeprazole were prepared to an initial concentration of 2 mg/mL. Suspensions were aliquoted into 5-mL doses in clear plastic oral syringes, and stored at 2-8 °C. Syringes from each batch were analyzed at baseline and after 7, 14, 21, and 30 days for omeprazole potency using HPLC. To assess suitability for NG tube administration, 20 mL of each suspension were administered through NG tubes (8Fr, 10Fr, and 18Fr), and percent omeprazole recovery assessed. Results: The chemical potency remained within 90-110% for 14 days and 30 days for compounded samples and FIRST-Omeprazole samples, respectively. There was a statistically significant difference in initial concentration; 1.89 mg/mL versus 1.98 mg/mL for compounded and FIRST-Omeprazole, respectively. After 30 days, FIRST-Omeprazole demonstrated 97.20% API recovery. Neither suspension experienced statistically significant loss of potency following NG tube passage. Conclusion: FIRST-Omeprazole suspension may be stored in refrigerated clear luer-lock oral syringes for 30 days. Traditionally compounded omeprazole suspension should be used within 14 days. Both suspensions are suitable for NG tube administration.
27

Caracterização e conservação pós-colheita de cambuci, fruto nativo da Mata Atlântica / Postharvest characterization and conservation of Cambuci, native fruit from the Brazillian Atlantic Forest

Tokairin, Tatiane de Oliveira 31 March 2017 (has links)
Diversas mirtáceas são nativas dos biomas brasileiros, sendo que a Mata Atlântica é o local onde muitas das espécies desta família ocorrem e têm grande importância pela qualidade de seus frutos. Dentre as espécies do gênero, o cambuci [Campomanesia phaea (O. Berg.) Landrum] é apontado com grande potencial funcional e sensorial que pode ser explorado comercialmente, devido às suas características nutricionais e funcionais. Entretanto, a carência de informações técnicas sobre a espécie, aliada à falta de tecnologias adequadas à conservação in natura e processamento dos frutos, colocam em risco a exploração do seu potencial comercial e de consumo. Em decorrência desse panorama, os objetivos do presente trabalho foram: (1) avaliar a diversidade entre cambucizeiros originados de semente, quanto aos seus aspectos físicos e químicos, compostos bioativos e compostos voláteis, (2) determinar o ponto adequado de colheita e comportamento respiratório dos frutos e por fim, (3) investigar a influência da temperatura de armazenamento na qualidade e na fisiologia pós-colheita de cambuci, com o intuito de fornecer subsídios técnicos/científicos à exploração comercial desta frutífera. Os resultados da caracterização físico-química dos frutos e dos teores de voláteis revelaram diferenças entre as árvores matrizes, os locais de colheita e entre as safras dos anos de 2014 e 2015. O estádio de maturação 2, caracterizado por frutos maduros colhidos na planta, com coloração verde-amarelada e região equatorial levemente arredondada, foi definido como o ponto de colheita ideal para cambuci. Os frutos do E2 possuíam qualidade igual ou superior aos frutos dos outros estádios avaliados, tendo menor adstringência, conteúdo superior de ácido ascórbico e vida-útil pós-colheita acrescida em pelo menos 2 dias, por terem menor perda por podridões, maior firmeza da polpa e menor perda de massa frutos. Os frutos cambuci apresentaram padrão respiratório não-climatérico. Apresentaram também alteração da qualidade sensorial, ao longo dos dias após a colheita, entre os estádios de maturação, constatado pelo perfil dos compostos voláteis, tanto pela abundância de metabólitos, como pela nota aromática. Frutos mais verdes apresentam aromas herbáceo, etéreo ou pungente e à medida que amadureceram passaram a apresentar aromas frutados e canforados. O armazenamento dos frutos a baixa temperatura comprovou ser uma alternativa viável para a pós-colheita dos frutos de cambuci, contribuindo para a sua conservação, prolongando sua vida útil. Os resultados obtidos abrem perspectivas para o desenvolvimento da fruticultura do cambuci, haja vista a variabilidade genética entre os genótipos produtivos aqui demonstrada. Dessa forma, há subsídios para a implementação de programas de melhoramento da espécie com vistas ao aumento na produtividade dos plantios, atendendo à sua cadeia produtiva. Ademais, os resultados dão suporte para a definição de procedimentos de pós-colheita do cambuci, fundamentados em informações técnicas que garantem metodologia específica para a colheita e armazenagem dos frutos de cambuci. Portanto, os resultados descritos representam um avanço frente à definição de práticas de colheita e armazenagem dos frutos, garantindo assim a expansão da fruticultura da espécie. / There are several Myrtaceae native to the Brazilian biomes, being the Atlantic Forest the place where many of them occur, having great importance for the quality of its fruits. Among the species of the genus, cambuci [Campomanesia phaea (O. Berg.) Landrum] has great functional and sensorial potential, being able to be exploited commercially due to its nutritional and phytotherapeutic characteristics. However, the lack of technical information about the species, coupled with the lack of appropriate technologies for in natura conservation and fruit processing, delay the exploitation of its commercial and consumption potential. Due to this background, the objectives of this study were: (1) assess the diversity among cambucizeiros originated by seeds and their physical and chemical quality, bioactive compounds and volatile compounds, (2) determine the appropriate maturity stage for harvest and respiration rate, (3) to investigate the influence of storage temperature on cambuci quality and postharvest physiology, with the purpose of providing technical/scientific subsidies to the commercial exploitation of this fruit. The results of the physicochemical characterization of the fruits and the volatile contents revealed differences between the matrix trees, harvesting sites and between the harvests of 2014 and 2015. The maturation stage 2, characterized by ripe fruits harvested in the plant, with a yellowish-green coloration and slightly rounded equatorial region, was defined as the ideal picking for cambuci. The fruits had an equal or higher quality than the fruits of the other maturity stages, with lower astringency, higher ascorbic acidcontent and postharvest life at least 2 days larger. These results were obtained because in this maturity stages, fruits had less rot loss, greater pulp firmness and fresh weight loss. The cambuci fruits showed a non-climacteric respiratory pattern. They also showed changes in the sensorial quality, along the days after harvesting and between the stages of maturation, verified by the volatile compounds, the abundance of metabolites and aromatic notes. Greener fruits have herbaceous, ethereal or pungent aromas, and as they mature, they have fruity and camphorated aromas. The fruits storage at low temperature proved to be a viable alternative for the postharvest of cambucis, contributing to its conservation, prolonging its shelf-life, without compromising its quality. The results obtained open perspectives for the development of cambuci produce, given the genetic variability among the productive genotypes demonstrated here. Thus, there are subsidies for the implementation of breeding programs of the species for increasing the productivity, considering their productive chain. In addition, the results support the definition of postharvest procedures for cambuci, foundations in technical information that guarantee specific methodology for the harvest and storage of cambuci fruits. Therefore, the results described here represent an advance in harvesting practices and storage of the cambuci fruits, guaranteeing the expansion of production of the species.
28

Caracterização e conservação pós-colheita de cambuci, fruto nativo da Mata Atlântica / Postharvest characterization and conservation of Cambuci, native fruit from the Brazillian Atlantic Forest

Tatiane de Oliveira Tokairin 31 March 2017 (has links)
Diversas mirtáceas são nativas dos biomas brasileiros, sendo que a Mata Atlântica é o local onde muitas das espécies desta família ocorrem e têm grande importância pela qualidade de seus frutos. Dentre as espécies do gênero, o cambuci [Campomanesia phaea (O. Berg.) Landrum] é apontado com grande potencial funcional e sensorial que pode ser explorado comercialmente, devido às suas características nutricionais e funcionais. Entretanto, a carência de informações técnicas sobre a espécie, aliada à falta de tecnologias adequadas à conservação in natura e processamento dos frutos, colocam em risco a exploração do seu potencial comercial e de consumo. Em decorrência desse panorama, os objetivos do presente trabalho foram: (1) avaliar a diversidade entre cambucizeiros originados de semente, quanto aos seus aspectos físicos e químicos, compostos bioativos e compostos voláteis, (2) determinar o ponto adequado de colheita e comportamento respiratório dos frutos e por fim, (3) investigar a influência da temperatura de armazenamento na qualidade e na fisiologia pós-colheita de cambuci, com o intuito de fornecer subsídios técnicos/científicos à exploração comercial desta frutífera. Os resultados da caracterização físico-química dos frutos e dos teores de voláteis revelaram diferenças entre as árvores matrizes, os locais de colheita e entre as safras dos anos de 2014 e 2015. O estádio de maturação 2, caracterizado por frutos maduros colhidos na planta, com coloração verde-amarelada e região equatorial levemente arredondada, foi definido como o ponto de colheita ideal para cambuci. Os frutos do E2 possuíam qualidade igual ou superior aos frutos dos outros estádios avaliados, tendo menor adstringência, conteúdo superior de ácido ascórbico e vida-útil pós-colheita acrescida em pelo menos 2 dias, por terem menor perda por podridões, maior firmeza da polpa e menor perda de massa frutos. Os frutos cambuci apresentaram padrão respiratório não-climatérico. Apresentaram também alteração da qualidade sensorial, ao longo dos dias após a colheita, entre os estádios de maturação, constatado pelo perfil dos compostos voláteis, tanto pela abundância de metabólitos, como pela nota aromática. Frutos mais verdes apresentam aromas herbáceo, etéreo ou pungente e à medida que amadureceram passaram a apresentar aromas frutados e canforados. O armazenamento dos frutos a baixa temperatura comprovou ser uma alternativa viável para a pós-colheita dos frutos de cambuci, contribuindo para a sua conservação, prolongando sua vida útil. Os resultados obtidos abrem perspectivas para o desenvolvimento da fruticultura do cambuci, haja vista a variabilidade genética entre os genótipos produtivos aqui demonstrada. Dessa forma, há subsídios para a implementação de programas de melhoramento da espécie com vistas ao aumento na produtividade dos plantios, atendendo à sua cadeia produtiva. Ademais, os resultados dão suporte para a definição de procedimentos de pós-colheita do cambuci, fundamentados em informações técnicas que garantem metodologia específica para a colheita e armazenagem dos frutos de cambuci. Portanto, os resultados descritos representam um avanço frente à definição de práticas de colheita e armazenagem dos frutos, garantindo assim a expansão da fruticultura da espécie. / There are several Myrtaceae native to the Brazilian biomes, being the Atlantic Forest the place where many of them occur, having great importance for the quality of its fruits. Among the species of the genus, cambuci [Campomanesia phaea (O. Berg.) Landrum] has great functional and sensorial potential, being able to be exploited commercially due to its nutritional and phytotherapeutic characteristics. However, the lack of technical information about the species, coupled with the lack of appropriate technologies for in natura conservation and fruit processing, delay the exploitation of its commercial and consumption potential. Due to this background, the objectives of this study were: (1) assess the diversity among cambucizeiros originated by seeds and their physical and chemical quality, bioactive compounds and volatile compounds, (2) determine the appropriate maturity stage for harvest and respiration rate, (3) to investigate the influence of storage temperature on cambuci quality and postharvest physiology, with the purpose of providing technical/scientific subsidies to the commercial exploitation of this fruit. The results of the physicochemical characterization of the fruits and the volatile contents revealed differences between the matrix trees, harvesting sites and between the harvests of 2014 and 2015. The maturation stage 2, characterized by ripe fruits harvested in the plant, with a yellowish-green coloration and slightly rounded equatorial region, was defined as the ideal picking for cambuci. The fruits had an equal or higher quality than the fruits of the other maturity stages, with lower astringency, higher ascorbic acidcontent and postharvest life at least 2 days larger. These results were obtained because in this maturity stages, fruits had less rot loss, greater pulp firmness and fresh weight loss. The cambuci fruits showed a non-climacteric respiratory pattern. They also showed changes in the sensorial quality, along the days after harvesting and between the stages of maturation, verified by the volatile compounds, the abundance of metabolites and aromatic notes. Greener fruits have herbaceous, ethereal or pungent aromas, and as they mature, they have fruity and camphorated aromas. The fruits storage at low temperature proved to be a viable alternative for the postharvest of cambucis, contributing to its conservation, prolonging its shelf-life, without compromising its quality. The results obtained open perspectives for the development of cambuci produce, given the genetic variability among the productive genotypes demonstrated here. Thus, there are subsidies for the implementation of breeding programs of the species for increasing the productivity, considering their productive chain. In addition, the results support the definition of postharvest procedures for cambuci, foundations in technical information that guarantee specific methodology for the harvest and storage of cambuci fruits. Therefore, the results described here represent an advance in harvesting practices and storage of the cambuci fruits, guaranteeing the expansion of production of the species.
29

Survival of Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus in raw yellowfin tuna during refrigerated and frozen storage

Mou, Jing 06 March 2013 (has links)
The consumption of seafood in the United States has increased rapidly in recent years due to high quality protein and health benefits of seafood. Seafood can be a carrier for bacteria normally distributed in the marine environment and, in some cases, can be contaminated by human pathogens. Therefore, there is a potential health risk if seafood is consumed raw or undercooked. However, information regarding prevalence of foodborne pathogens in retail seafood products and the ability of pathogens to survive in the products during refrigerated and frozen storage is limited. The objective of this study was to generate such information for a better understanding of distribution of foodborne pathogens in seafood products and provide data which might be used for risk assessment of foodborne infection associated with seafood consumption. A total of 45 seafood products were collected from local retail stores and analyzed for aerobic plate counts (APC) and psychrotrophic bacterial counts (PBC) as well as presence of foodborne pathogens, including Escherichia coli O157:H7, Salmonella, Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemolyticus, and Vibrio vulnificus according to procedures described in the U.S. Food and Drug and Administration Bacteriological Analytical Manual (BAM). Presumptive isolates for each foodborne pathogen were further characterized by biochemical reactions using commercial identification kits and confirmed with polymerase chain reaction (PCR) assay. The samples had bacterial populations ranging from 1.90 to 6.11 CFU/g for APC and from 2.00 to 6.78 CFU/g for PBC. According to the microbiological criteria of International Commission on Microbiological Specifications for Foods (ICMSF), all 45 samples were considered acceptable quality (APC < 10⁷ CFU/g, E. coli < 3 MPN/g) with most samples (93.3%) being good quality (APC < 5 × 10⁵ CFU/g, E. coli < 3 MPN/g). No E. coli O157:H7, Salmonella, S. aureus, V. parahaemolyticus, and V. vulnificus was detected in any samples. Two previously frozen shrimp products (4.4%) were confirmed to carry L. monocytogenes. Studies of growth and survival of L. monocytogenes (3 strains), S. aureus (2 strains), and Salmonella (2 serovars) in raw yellowfin tuna meat stored at 5 - 7 °C for 14 days revealed that L. monocytogenes had the ability to multiply in the tuna meat during refrigerated storage while populations of S. aureus and Salmonella were reduced by 1 to 2 log CFU/g after 14 days at 5 - 7 °C. Studies of holding raw yellowfin tuna meat contaminated with L. monocytogenes, S. aureus, and Salmonella at -18 ± 2 °C for 12 weeks observed that all three pathogens, except Salmonella Newport, in tuna samples survived the frozen storage with less than 2- log of reductions in the populations over 12 weeks of storage. No viable cell of Salmonella Newport was detected in samples after 42 days storage at -18 °C. Raw seafood can be a carrier of foodborne pathogens, particularly L. monocytogenes, and many foodborne pathogens can survive in frozen products for several months. Consumption of raw or undercooked seafood products may lead to human infection if the products are contaminated with pathogens. Therefore, sanitation standard operating procedure (SSOP), good manufacturing practice (GMP) and hazards analysis and critical control points (HACCPs) programs shall all be implemented in the seafood industry to prevent seafood products from being contaminated with foodborne pathogens during handling and processing. Moreover, proper storage of raw seafood products and avoiding cross-contamination during handling at the retail levels also helps to minimize risk of human infection associated with ready-to-eat products. / Graduation date: 2013
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Estudo da qualdiade microbiológica, química, físico-química e sensorial de cenoura (Daucus carot, L.) submetida à tecnologia Sous vide produzida em escala industrial / Study of quality microbiological, phisical-chemical, chemical and sensory carrot (Daucus carot .L) submitted to sous vide produced industially technology.

Oliveira, Ticiane Coelho Abreu de January 2012 (has links)
OLIVEIRA, Ticiane Coelho Abreu de. Estudo da qualdiade microbiológica, química, físico-química e sensorial de cenoura (Daucus carot, L.) submetida à tecnologia Sous vide produzida em escala industrial. 2012. 98 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-28T16:00:36Z No. of bitstreams: 1 2012_dis_tcaoliveira.pdf: 741298 bytes, checksum: 355c053111b742e1184f6a1d19ca4110 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-28T16:00:50Z (GMT) No. of bitstreams: 1 2012_dis_tcaoliveira.pdf: 741298 bytes, checksum: 355c053111b742e1184f6a1d19ca4110 (MD5) / Made available in DSpace on 2016-06-28T16:00:50Z (GMT). No. of bitstreams: 1 2012_dis_tcaoliveira.pdf: 741298 bytes, checksum: 355c053111b742e1184f6a1d19ca4110 (MD5) Previous issue date: 2012 / The carrot is a crop rich in carotenoids, pro-vitamin A, minerals and carbohydrates, and is a food with high nutritional value. Brazil is among the five largest producers and consumers of carrot (Daucus carot L .) in the world, concentrating its production in the Southeast. In search of products more attractive, practical, nutritious and healt hy, the consumer's sous vide technology is an alternative technology for the industry in providing food ready for consumption. The sous vide consists in cooking food packaged in plastic vacuum -sealed, subjected to temperatures lower than 100°C for extended periods of time, chilled quickly and stored under refrigeration. The aim of this study was to evaluate the quality and shelf life of carrots ( Daucus carot L.) diced submitted to sous vide technology, produced on an industrial scale. The samples were subje cted to physical and chemical analysis and chemical, microbiological and with three replications, with five repetitions of the products, and soon after processing by 2, 4, 6 and 8 weeks of storage (3°C). Sensory analysis was carried out on days 0 and 4 weeks, with a repeat. The results indicated a significant difference of 5% (p ≤0.05) in carbohydrate, protein, ash, titratable acidity and chromaticity between the carrot fresh carrot and processed by sous vide technology at time 0. In times of 2, 4, 6 and 8 weeks of storage at 3°C difference was significant (p ≤ 0.05) only for protein and total acidity. In sensory analysis, no significant difference (p ≤ 0.05) in any of the attributes studied. It was also observed that the technology sous vide was effective in eliminating vegetative cells of micro-organisms pathogenic and spoilage, yet not been able to eliminate spores. The carrot processed by sous vide technology retains its nutritional characteristics, sensory, chemical and microbiologically stable for up to eight weeks of storage at 3ºC. / A cenoura é uma olerícola rica em carotenóides, pró-vitamina A, minerais e carboidratos, constituindo um alimento com alto valor nutritivo. O Brasil está entre os cinco maiores produtores e consumidores de cenoura (Daucus carot L.) do mundo, concentrando sua produção na região sudeste. Na busca de produtos mais atrativos, práticos, nutritivos e saudáveis pelo consumidor, a tecnologia sous vide surge como uma alternativa tecnológica para a indústria no fornecimento de pratos prontos para consumo. O sous vide consiste em cozinhar alimentos acondicionados em embalagens plásticas seladas à vácuo, submetidos a temperaturas inferiores à 100°C por longos períodos de tempo, resfriados rapidamente e armazenados sob refrigeração. O objetivo desse trabalho foi avaliar a qualidade e a vida de prateleira de cenouras (Daucus carot L.) cortadas em cubos submetida a tecnologia sous vide, produzida em escala industrial. As amostras foram submetidas as análises físico-químicas e químicas, com três repetições e microbiológicas, com cinco repetições, dos produtos, logo após o tecnologia e por 2, 4, 6 e 8 semanas de armazenamento refrigerado (3ºC). A análise sensorial foi realizada nos tempos de 0 e 4 semanas, com uma repetição. Os resultados indicaram que houve diferença significativa de 5% (p≤0,05) nos carboidratos, proteínas, cinzas, acidez total titulável e na cromaticidade entre a cenoura in natura e a cenoura processada por tecnologia sous vide no tempo 0. Nos tempos de 2, 4, 6 e 8 semanas de armazenamento a 3ºC houve diferença significativa (p≤0,05) apenas nas proteínas e acidez total titulável. Na análise sensorial, não houve diferença significativa (p≤0,05) em nenhum dos atributos estudado. Observou-se também que a tecnologia sous vide foi eficiente na eliminação de células vegetativas de micro-organismos deteriorantes e patogênicos, porém não foi capaz de eliminar esporos. A cenoura processada por tecnologia sous vide conservou suas características nutricionais, sensoriais, químicas e manteve-se estável microbiologicamente até oito semanas de armazenamento à 3ºC.

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