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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.
171

Composi??o de ?cidos graxos, teores de colesterol e ?xidos de colesterol em amostras comerciais de atuns em conservas / Fatty acid composition, cholesterol and cholesterol oxides contents in commercial samples of canned tuna

DANTAS, Natalie Marinho 04 May 2016 (has links)
CNPq / Brazil presents an important commercial fishing pole, which turns it to become relevant considering the benefits that consumption of fish plays in human nutrition. Canned fish promotes long shelf life of these food. However, foods that are rich sources of polyunsaturated fatty acids and cholesterol, such as tuna, have a great susceptibility for lipid oxidation when exposed to thermal processing. Cholesterol oxidation products (COP?s) are related to several diseases such as atherosclerosis, and can be absorbed from the diet. Thus, this study aimed to evaluate the lipid composition and COP?s production in canned tuna purchased from metropolitan area of Rio de Janeiro. Three trademarks of ?grated in brine? and ?in oil? canned tuna were evaluated. To determinate lipid oxidation, the fatty acid composition from the methyl esters of the fish and their brine were identified using gas chromatography with flame ionisation detector; cholesterol and cholesterol oxides were determined simultaneously, using high-performance liquid chromatography and confirmed by liquid chromatograph mass spectrometer (chemical ionization interface for atmospheric pressure) (APCI-MS). Tuna in ?brine? samples presented moisture contents in a range of 24.60 to 27.23g/100g; lipids contents ranging from 4.21 to 5.59g/100g; polyunsaturated fatty acids (PUFA) levels between 9.13 to 16,20g/100g, and high saturated fatty acids (SFA) contents (in a range of 54.66 to 59.85g/100g) (dry basis-DB). The nutritional quality index showed that lipid fractions presented undesirable values. These samples presented cholesterol concentration ranging from 190.95 to 399.28mg/100g, and high cholesterol oxidation products contents (between 321.42 and 414.94?g/100g- DB). Samples of ?in oil? canned tuna presented moisture and lipids contents of 31.93 to 51.33g/100g and 23.70 to 43.99g/100g, respectively; high polyunsaturated fatty acids concentration (46.06 to 49.92g/100g), especially the w6 series; and low levels of EPA and DHA amounts (in a range of 0.59 and 1.73g/100g). Cholesterol and COP?s contents varied from 135.90 to 191.92mg/100g and from 110.97 to 207.19?g/100g, respectively. Significate concentrations of cholesterol were identified in brine (18.99 to 37.10mg/100g) and ?in oil? samples (113.09 to 259.12mg/100g), and high COP?s contents were found (in a range of 230.54 and 477.12?g/100g from brine and 44.15 to 151.18?g/100g from ?in oil? samples). It was observed that there is a transference of lipids from fish to brine, as well as migration between fish lipids and vegetable oils in the ?oil? covers, changing the fatty acids profiles of both. It is considered that the production of canned fish contributes to loss of lipid quality, promotes fatty acids oxidation and induces the formation of cholesterol oxidation products. These results indicate that is necessary to conduct further studies to evaluate the occurrence of these undesirable compounds in fish products. / O Brasil possui um importante polo de pesca comercial, fato que se torna relevante considerando os benef?cios que o consumo de pescados desempenha na nutri??o humana. As conservas de peixes promovem nestes alimentos tempos de vida ?til prolongados. Entretanto, os alimentos ricos em ?cidos graxos poliinsaturados e colesterol, como os atuns, quando submetidos ao processamento t?rmico, apresentam grande potencial para a oxida??o lip?dica. Os produtos da oxida??o do colesterol (POC?s) est?o envolvidos no desenvolvimento de doen?as, como a aterosclerose, e podem ser absorvidos a partir da dieta. Desta forma, este trabalho teve como objetivos avaliar a composi??o lip?dica e a forma??o dos POC?s em conservas de atuns comercializadas na regi?o metropolitana do Rio de Janeiro. Foram avaliadas amostras de conservas ?raladas? em ?salmoura? e em ??leo? de 3 marcas comerciais. Para determina??o da oxida??o lip?dica, identificou-se a composi??o de ?cidos graxos dos atuns e respectivos l?quidos de coberturas a partir dos ?steres met?licos, atrav?s de Cromatografia Gasosa com detector de ioniza??o por chama; al?m da quantifica??o simult?nea do colesterol e dos POC?s, atrav?s de cromatografia l?quida de alta efici?ncia e confirmados por cromat?grafo l?quido com espetr?metro de massas (interface de ioniza??o qu?mica por press?o atmosf?rica) (APCI-MS). Os atuns em ?salmoura? apresentaram m?dias entre 24,60 a 27,23g/100g de umidade; entre 4,21 a 5,59g/100g de lip?deos; teores de 9,13 a 16,20g/100g de ?cidos graxos poliinsaturados (AGPI), e elevadas concentra??es de ?cidos graxos saturados (AGS) (entre 54,66 a 59,85g/100g), em base seca (BS). Foram evidenciados nos ?ndices de qualidade nutricional das fra??es lip?dicas com valores pouco desej?veis sob o ponto de vista nutricional. As concentra??es de colesterol nessas amostras variaram entre 190,95 a 399,28mg/100g, e foram identificados elevados teores de produtos de oxida??o do colesterol (entre 321,42 e 414,94?g/g/100g), em BS. As amostras de atuns em conservas contendo ??leo? apresentaram teores entre 31,93 e 51,33g/100g de umidade; entre 23,70 e 43,99g/100g de lip?deos, elevadas concentra??es de ?cidos graxos poliinsaturados (de 46,06 a 49,92g/100g), em especial os da s?rie w6 e reduzidos teores na soma de EPA e DHA (entre 0,59 e 1,73g/100g). As concentra??es de colesterol variaram entre 135,90 e 191,92mg/100g e os POC?s de 110,97 a 207,19?g/100g. Em rela??o aos l?quidos de coberturas, foram identificadas concentra??es significativas de colesterol (de 18,99 a 37,10mg/100g nas salmouras e de 113,09 a 259,12mg/100g nos ?leos, respectivamente), al?m de elevados teores de produtos de oxida??o do colesterol (entre 230,54 e 477,12?g/100g nas salmouras e entre 44,15 e 151,18?g/100g nos ?leos). Observou-se a transfer?ncia de lip?deos dos pescados para os l?quidos em ?salmoura?, al?m da migra??o de lip?deos entre os pescados e os ?leos vegetais nas conservas em ??leo?, alterando os perfis de ?cidos graxos de ambos os meios. Considera-se que a produ??o de conservas de peixes favorece a perda da sua qualidade lip?dica, promovem oxida??o de ?cidos graxos e induzem a forma??o de produtos de oxida??o do colesterol, fato que indica a necessidade da condu??o de novos estudos que avaliem a ocorr?ncia desses compostos indesej?veis oriundos da oxida??o lip?dica em produtos de pescados.
172

Emiss?es de ?xido nitroso (N2O) de Cambissolo cultivado com cana-de-a??car em Campos dos Goytacazes: impacto de aduba??es com vinha?a e ur?ia / Nitrous oxide emission (N2O) from a Cambisol (Inceptisol) cultivated with sugarcane in Campos dos Goytacazes: Impact of vinasse and urea applications

ZUCHELLO, Fernando 10 March 2010 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-07T16:44:20Z No. of bitstreams: 1 2010 - Fernando Zuchello.pdf: 1133928 bytes, checksum: cc66d828c0f6af539cc639528ca1d2fb (MD5) / Made available in DSpace on 2017-04-07T16:44:20Z (GMT). No. of bitstreams: 1 2010 - Fernando Zuchello.pdf: 1133928 bytes, checksum: cc66d828c0f6af539cc639528ca1d2fb (MD5) Previous issue date: 2010-03-10 / CAPES / The sugarcane crop (Saccharum officinarum L.) produces raw material for ethanol manufacture, a fuel with high potential for mitigation of greenhouse gases. However, little information about emissions of nitrous oxide (N2O) from soil during crop development is available. Nitrous oxide is one of the greenhouse gases, and agriculture is the main source of emissions to atmosphere. Thus, agricultural practices commonly in sugarcane cropping systems, such as vinasse and N fertilizer application, may favour the emissions of this gas, reducing or even nullifying the mitigating effect of ethanol. The objective of this study was to evaluate the effect of vinasse and urea application on sugarcane crop regarding to N2O emission from an Inceptisol in Campos dos Goytacazes municipality, Rio de Janeiro State. The study was carried out at the Leonel Miranda Experimental Station, UFRRJ, with soil N2O emissions being monitored in two experiments. In the first, the cane was in the third ratoon, comprising the period from November 2008 to April 2009. The second experiment was conducted in September and October of 2009, when the crop was renewed (cane first growth). For both experiments, the experimental design was completely randomized plots with 6 replications. The treatments of the first experiment were: addition of vinasse and urea on the soil with straw, addition of vinasse and urea on a bare soil, and the respective controls with and without straw. In the second experiment, the presence of straw was not evaluated. In all occasions vinasse was broadcasted, and urea was applied in bands. The N2O fluxes were measured by closed-static chamber technique. Temperature, soil moisture at 10 cm depth, mineral N and ammonia volatilization were also monitored. During the months of November and December 2008, there was intense rainfall in the first 20 days after application of vinasse; the accumulated precipitation was over 374 mm. Because of this, the water filled pore space (WFPS) were about 100% for most of the first 20 days. After application of urea, a new period of heavy rainfall started, between 10 and 31/12/2008, with an accumulated precipitation of 297 mm, again favouring increase of WFPS. Under those conditions, the straw did not bring any effect on N2O fluxes, which remained almost unaltered during the whole period. In the second experiment, the effect of vinasse and N addition was clear. The fractions of the two sources of N lost as N2O were 0.02% in the first experiment, regardless of the N source, and in the second experiment it was of 0.02 and 0.13% for vinasse and urea, respectively. Based on the results, vinasse was not an important source of N2O. The effect of urea was too variable, with losses by NH3 volatilization and emitted N2O dependent on rainfall. In the studied environment, key variables for production of N2O in soils such as WFPS and mineral N availability did not explain changes in N2O fluxes, which could be explained by conditions of maximum water soil saturation, for several days during the study. / A cultura da cana-de-a??car (Saccharum officinarum L.) gera mat?ria prima para a produ??o de etanol, combust?vel com alto potencial de mitiga??o de gases de efeito-estufa. No entanto, existem poucas informa??es sobre as emiss?es de ?xido nitroso (N2O) do solo, durante o desenvolvimento da cultura. O N2O ? um dos gases respons?veis pelo efeito estufa, e a agr?cultura ? a sua principal fonte para a atmosfera. Assim, pr?ticas agr?colas comuns no cultivo da cana, como aplica??o de vinha?a e fertilizante nitrogenado, podem favorecer a emiss?o desse g?s, reduzindo ou mesmo anulando o aspecto mitigador do etanol no efeito estufa. O objetivo do estudo foi avaliar o efeito da aplica??o de vinha?a e ur?ia na cultura de cana-de-a??car quanto ?s emiss?es de N2O de Cambissolo Fl?vico, em Campos dos Goytacazes, RJ. O estudo foi realizado no Campus Experimental Leonel Miranda, da UFRRJ, com o monitoramento das emiss?es de N2O feito em dois experimentos. No primeiro, a cultura estava na terceira soca, no per?odo de novembro de 2008 a abril de 2009. O segundo foi feito nos meses de setembro e outubro de 2009, quando a cultura foi renovada (cana-planta). Os dois experimentos foram conduzidos em delineamento inteiramente casualizado, com 6 repeti??es. Os tratamentos avaliados foram: adi??o de vinha?a e ur?ia em solo coberto com palhada, adi??o de vinha?a e ur?ia em solo nu, e os respectivos controles sem adi??o de vinha?a e ur?ia. Os tratamentos com palha foram usados somente no primeiro experimento, na fase de socaria. Vinha?a e ur?ia foram aplicadas em cobertura e a ?ltima em banda. A emiss?o de N2O foi avaliada no local com c?maras est?ticas fechadas, sendo tamb?m monitorados a temperatura, a umidade do solo a 10 cm de profundidade, a disponibilidade de N mineral e o teor de am?nia volatilizada. Durante os meses de novembro e dezembro houve intensa pluviosidade onde, nos primeiros 20 dias ap?s a aplica??o da vinha?a, a chuva acumulada foi superior a 374 mm. Devido a isso, a satura??o dos poros com ?gua (EPSA) se aproximou de 100% durante boa parte desses 20 dias. Ap?s a aplica??o da ur?ia, ocorreu novo per?odo com fortes chuvas, entre os dias 10 e 31/12/2008, alcan?ando 297 mm favorecendo novamente a eleva??o do EPSA. Nessas condi??es, a palha n?o trouxe efeito nos fluxos de N2O do solo. No primeiro experimento a aplica??o de vinha?a e da ur?ia n?o resultou em fluxos de N2O elevados, somente na aplica??o da ur?ia foi observada diferen?a em rela??o ao controle. No segundo experimento o efeito das fontes de N foi mais pronunciado. As fra??es de N das duas fontes perdidas como N2O foram de 0,02% no primeiro experimento, independente da fonte, e, no segundo experimento, de 0,02 e 0,13% para vinha?a e ur?ia, respectivamente. Portanto, a vinha?a aplicada ao solo foi fonte de N2O insignificante. O efeito da ur?ia foi muito vari?vel, com perdas por volatiliza??o de am?nia e emiss?es de N2O dependentes da ocorr?ncia de chuvas. No ambiente estudado, as vari?veis consideradas chave para a produ??o de N2O do solo tais como a satura??o do espa?o poroso do solo com ?gua e a disponibilidade de N mineral, n?o explicaram as diferen?as de fluxos de N2O, o que parece estar relacionado ao processo de desnitrifica??o em condi??es de m?xima satura??o do solo com ?gua, que ocorreu por v?rios dias durante o estudo.
173

Determina??o da erodibilidade e do fator cobertura e manejo do solo sob condi??es de chuva natural e simulada / Determination of erodibility and soil cover and management factor under natural and simulated rain

EDUARDO, Eliete Nazar? 27 February 2012 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-04-25T20:29:14Z No. of bitstreams: 1 2012 - Eliete Nazar? Eduardo.pdf: 947644 bytes, checksum: d85c318ce9c161ce157d42e89ed6c4af (MD5) / Made available in DSpace on 2017-04-25T20:29:14Z (GMT). No. of bitstreams: 1 2012 - Eliete Nazar? Eduardo.pdf: 947644 bytes, checksum: d85c318ce9c161ce157d42e89ed6c4af (MD5) Previous issue date: 2012-02-27 / FAPERJ / The purpose of this study was to determine the soil erodibility (K) and soil cover and management factor (C) under natural and simulated rainfall in an Udult soil in Serop?dica, Rio de Janeiro State, Brazil. In the study with natural rainfall, the soil losses (SL) were evaluated from measurements in Wischmeier standard-plots in the period of 2006 to 2011, with their respective erosivity index (EI30). The soil erodibility values were calculated from the ratio of soil loss and the annual rainfall erosivity (Ka) and total period (Kt), considering the angular coefficient generated from the linear regression analysis between those parameters (Kci and Kct). For the determination of C factor under natural rainfall, it was evaluated the treatments maize in contour lines (MN) and maize in slope lines (MMA) during three years of cultivation. In the study with simulated rainfall, soil losses were evaluated during the period of September to December 2011, under the same treatments (MN and MMA). The soils erodibility under natural rainfall for 5 years of study is 0.0090 Mg ha h ha-1 MJ-1 mm-1. For the simulated rain, this value is 0.00021 Mg ha h ha-1 MJ-1 mm-1; under natural rainfall, the average values of C factor calculated are 0.0070 and 0.0132 Mg ha Mg-1 ha-1, respectively, for maize grown in contour and slope line, and 0.0932 and 0.1298 Mg ha Mg-1 ha-1 under simulated rainfall. In both studies, the C factor showed higher values in the beginning of the study period, decreasing with the evolution of culture. The higher C factor values obtained in the study with simulated rainfall are associated with higher erosivity index resulting from the characteristics adopted in the use of simulator rainfall. / O objetivo desse trabalho foi determinar a erodibilidade do solo (K) e o fator manejo e cobertura do solo (C), sob chuva natural e simulada, em um ARGISSOLO VERMELHO-AMARELO em Serop?dica (RJ), informa??es necess?rias para o planejamento do uso da terra e conserva??o do solo e da ?gua. No estudo com chuva natural foram avaliadas as perdas de solo (PS) ocorridas em parcelas padr?o de Wischmeier, no per?odo de 2006 a 2011, com seus respectivos ?ndices de erosividades (EI30). As erodibilidades do solo foram calculadas pelo quociente entre a perda de solo e a erosividade das chuvas anuais (Ka) e total no per?odo (Kt), considerando o coeficiente angular gerado na an?lise de regress?o linear entre esses mesmos par?metros (Kci e Kct). Para a determina??o do fator C, sob chuva natural foram avaliados os tratamentos de milho em n?vel (MN) e de milho morro a baixo (MMA) em tr?s anos de cultivo. No estudo com chuva simulada, as perdas de solo foram avaliadas no per?odo de setembro a dezembro de 2011, sob os mesmos tratamentos (MN e MMA). A erodibilidade do solo estudado sob chuva natural, para 5 anos de estudo ? de 0,0090 Mg ha h ha-1 MJ-1 mm-1. Para a chuva simulada, esse valor ? de 0,00021 Mg ha h ha-1 MJ-1 mm-1; sob chuva natural, os valores m?dios do fator C calculados s?o de 0,0070 e 0,0132 Mg ha Mg-1 ha-1, respectivamente, para a cultura do milho cultivado em n?vel e morro abaixo, e de 0,0932 e 0,1298 Mg ha Mg-1 ha-1 sob chuva simulada. Em ambos os estudos, o fator C apresentou maiores valores no in?cio do per?odo avaliado, decrescendo com a evolu??o da cultura. Os elevados valores do fator C obtidos no estudo com chuva simulada est?o associados ao elevado ?ndice de erosividade resultante das caracter?sticas adotadas no uso do simulador de chuva.
174

Uso da abordagem estat?stica procrusteana em Ecologia de Solo: caso de estudo envolvendo sistema de integra??o lavoura-pecu?ria-floresta no Cerrado / Uses of the procrustean statistical approach in soil ecology: a case of study involving an integrated agroecosystem in Brazilian savannah

LISBOA, Francy Junio Gon?alves 25 February 2015 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-02T21:19:46Z No. of bitstreams: 1 2015 - Francy Junio Gon?alves Lisboa.pdf: 2939884 bytes, checksum: c4aa4152d0d3ca90c85ecb78ff7e5da6 (MD5) / Made available in DSpace on 2017-05-02T21:19:46Z (GMT). No. of bitstreams: 1 2015 - Francy Junio Gon?alves Lisboa.pdf: 2939884 bytes, checksum: c4aa4152d0d3ca90c85ecb78ff7e5da6 (MD5) Previous issue date: 2015-02-25 / CAPES / This thesis is part of a multiple scientific effort seeking to support the replacement of degraded brazilian pastures by systems which integrate different land use types such as crop, pasture, and forest plantation (collectively known as iCLF systems). Here, the focus was also to discuss the potentialities of an unusual statistical multivariate approach called ?Procrustes Analysis? in the plant and soil ecology framework. The current thesis has three chapters through which details of the Procrustes analysis are presented on both technically e intuitively manner. The first chapter describes roadmaps showing how the procrustean residual vector (so-called PAM: Procrustean association metric), representing the multivariate correlation between two or more data tables, can be used as an univariate variable in more user-traditional statistical approaches such as ecological ordination, regression analysis and ANOVA followed by mean comparisons. The second chapter discussed a case study and had as the general objective to use PAMs, depicting the relationships between distance matrices from individual soil microbial structure (PLFA: Phospholipids Fatty Acid) and distance matrices form soil properties variables (chemical and physic), as response variables in an ANOVA framework with land use type as categorical predictor (degraded pasture, improved pasture, native fragment and iCLF system). The hypothesis in this case was that the fungi:bacteria ratio given by PLFA analysis, a good index of changes in microbial structure as response to land use alteration and associated to more conservative soils in terms of carbon mineralization, is favored by the man ? introduced vegetal heterogeneity which characterizes the integration crop ? livestock ? forest. The last chapter was entirely dedicated to answer some technical questions which arose after the publication of the first chapters. Basically the two most common questions were: i) Does the increasing number of columns/variables within a data table affect Procrustes outcomes? ii) Can the procrustean residual vector, the PAM, translate differences between treatments in terms of multivariate correlation as it is used in mean comparisons? Specifically for these questions, Procrustes was useful in supporting iCLF systems as potential alternative to degraded pasture by raising insights that the man ? introduced vegetal heterogeneity in such integrated agroecosystem, favor shifts in microbial structure toward fungal dominance. / A presente tese fez parte do esfor?o multinstitucional buscando sustentar a substitui??o de pastagens degradas por sistemas que integrem diferentes tipos de uso da terra, mais especificamente aqueles integrando lavoura, pastagem, e floresta plantada, coletivamente: sistemas iLPF. Aqui, o foco foi a explora??o das potencialidades da abordagem estat?stica denominada an?lise Procrutes, ou simplesmente Procrustes, na seara de ecologia de planta e solo. Basicamente, a tese foi composta por tr?s cap?tulos onde ? descrito com detalhes os principais nuances dessa abordagem multivariada ainda pouco utilizada por ecologistas de planta e solo. O primeiro cap?tulo descreve roteiros esquem?ticos mostrando como o vetor de res?duos derivado da correla??o e duas tabelas de dados pela an?lise Procrustes (chamado PAM: Procrustes association metric) pode ser utilizado como representante univariado da correla??o em outras abordagens estat?sticas (ordena??o ecol?gica, regress?o, e ANOVA seguida de teste de m?dias). O segundo cap?tulo da tese, utilizando sugest?es do primeiro cap?tulo, tratou de um estudo de caso. Neste caso, fazenda experimental situada no munic?pio de Cachoeira dourada ? GO, e contendo quatro diferentes tipos de uso da terra, dentre os quais um sistema iLPF, foi escolhida para a condu??o do estudo de caso. O objetivo geral foi acessar como correla??es, no formato de PAM, entre tabelas de dados representadas por vari?veis individuais de estrutura microbiana (dada por an?lise de lip?dios oriundos do solo; PLFA: Phospholipids Fatty Acid) e propriedades individuais de qu?mica e f?sica de solo, eram moduladas pelo tipo de uso da terra: pastagem degradada, pastagem melhorada, fragmento de mata nativa, e sistema iLPF. A hip?tese para o estudo de caso foi a de que a rela??o fungo: bact?ria, comumente associada a ambientes mais conservativos, era promovida pelo sistema iLPF uma vez que tais sistemas s?o caracterizados pelo aumento da heterogeneidade vegetal oriunda da sistematizada introdu??o de especies arb?reas em meio a pastagem. O terceiro e ?ltimo cap?tulo da tese foi estritamente dedicado a responder questionamentos t?cnicos referentes ? abordagem procrusteana e surgidos depois das publica??es dos dois primeiros cap?tulos da tese. Neste caso, dois dos questionamentos mais comuns foram abordados. Foram eles: i) quais s?o os efeitos da correla??o entre colunas/vari?veis dentro de uma tabela de dados sobre os resultados da an?lise Procrustes? ii) Pode o vetor de res?duos procrusteanos, a PAM, traduzir diferen?as entre tratamentos em termos da for?a de correla??o multivariada entre duas tabelas de dados? Para o estudo de caso os resultados da corrente tese suportaram os sistemas iLPF como potencial alternativa para substitui??o de pastagens degradadas ao levantar ind?cios de que a heterogeneidade vegetal introduzida nos sistemas iLPF pode favorecer o deslocamento da estrutura microbiana em dire??o ao dom?nio de fungos.
175

Desidrata??o osm?tica de banana utilizando solu??es de fruto-oligossacar?deos e xarope de milho em diferentes temperaturas / Study banana osmotic dehydration using solutions containing fructo-oligosaccharides and corn syrup at different temperatures

LANDIM, Ana Paula Miguel 02 June 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-09T17:18:58Z No. of bitstreams: 1 2016 - Ana Paula Miguel Landim.pdf: 1756748 bytes, checksum: edb655700eacaf99a7fa2c3d482f3283 (MD5) / Made available in DSpace on 2017-05-09T17:18:58Z (GMT). No. of bitstreams: 1 2016 - Ana Paula Miguel Landim.pdf: 1756748 bytes, checksum: edb655700eacaf99a7fa2c3d482f3283 (MD5) Previous issue date: 2016-06-02 / CAPES / Banana is a perishable fruit, as it ripens fast and cannot be adequately preserved by the cold, resulting in large post-harvest losses. The application of preservation techniques, such as osmotic dehydration, reduces losses of the commodity in post-harvest stage, extend its shelf-life, while not severely affecting its nutritional values, and functional and sensorial properties, which makes it at processing alternative for the fruit. The aim of this study is to evaluate the kinetics of osmotic dehydration, as well as the quality of the osmotically dehydrated samples in terms of color, texture, and antioxidant capacity, using fructo-oligosaccharide, corn syrup and the mixture of both, under different temperatures. To determine the kinetics, the fruit, cut in cubes, was dehydrated in different solutions, under temperatures of 40, 50 and 60 ? C. The kinetics of water loss (WL) and solid gain (SG) were evalueted at 30, 60, 90, 120, 180, 240, 360, 720 to 1440 minutes. The analysis of variance was used to verify the effect of each solution and temperature on kinetics. The kinetic parameters were modeled based on the equations of Peleg, Page modified and Barbosa Junior et al. using non-linear regression. The time to reduce the dehydration rate or penetration to one third of its initial values (t(1/3)) and the process average time (t(average)) were obtained on the Barbosa Junior et al. model The quality of the samples was accessed at these two times, in different solutions under different temperatures. For such, the variation of the instrumental parameters of color, antioxidant capacity (FRAP, DPPH and total phenolic content), and texture (axial compression tests) of samples, in nature as well as processed, were verified. The WL was not affected significantly by the type of solute used, however, the temperature presented significant influence over these parameters (p < 0.05). The experimental data for the WL was adequately adjusted to the Peleg and Page modified models with coefficients of determination (R?) superior than 0.98, mean relative error (E) inferior than 6.5% in all treatments. The water loss content values varied from 15.75 to 28.79% at time t(1/3), while for the time t(averege) 15.75 to 30.27% between treatments. The process of osmotic dehydration had affect on the quality of the final product, showing significant differences between the fruits in natura and processed state, in terms of color, antioxidant capacity and texture of the samples. / A banana ? um fruto perec?vel, pois sofre r?pido amadurecimento, n?o pode ser devidamente conservado pelo frio, sendo acometido por grandes perdas p?s-colheita. A utiliza??o de t?cnicas de conserva??o, como a desidrata??o osm?tica, reduz as perdas p?s-colheita, estende a validade comercial, n?o acarreta em severas altera??es nas caracter?sticas nutricionais, funcionais e sensoriais e mostra-se como uma alternativa de processamento para este fruto. O objetivo desde trabalho foi avaliar a cin?tica da desidrata??o osm?tica, bem como, a qualidade das amostras desidratadas osmoticamente em termos de cor, textura e capacidade antioxidante, utilizando fruto-oligossacar?deo, xarope de milho e a mistura de ambos, em diferentes temperaturas. Para determina??o da cin?tica, a banana, cortada em cubos foi desidratada nas diferentes solu??es, sob as temperaturas de 40, 50 e 60 ?C. As Cin?ticas de Perda de ?gua (PA) e ganho de s?lidos (GS) foram avaliadas nos tempos 30, 60, 90, 120, 180, 240, 360, 720 e 1440 minutos. A an?lise de vari?ncia foi usada, a fim de verificar o efeito do tipo de soluto e da temperatura na cin?tica. Os par?metros cin?ticos foram modelados de acordo com a equa??o Peleg, Page modificado e Barbosa J?nior et al. utilizando regress?o n?o-linear. A partir do modelo de Barbosa J?nior et al., obteve-se o tempo para reduzir a taxa de desidrata??o ou impregan??o a um ter?o de seus valores iniciais (t(1/3)) e o tempo m?dio de processo (t(m?dio)). A qualidade das amostras foi avaliada nestes dois tempos, nos diferentes solutos e temperaturas. Para tal, foram verificadas a varia??o dos par?metros instrumentais de cor, a capacidade antioxidante (FRAP, DPPH e teor de fen?licos totais) e a textura (ensaios de compress?o axial) das amostras in natura e processadas. A PA n?o foi afetada significamente pelo tipo de soluto empregado, no entanto, a temperatura apresentou influ?ncia significativa neste par?metro (p < 0,05). Os dados experimentais para a PA se ajustaram adequadamente ao modelo de Peleg e Page modificado e obtiveram-se coeficientes de determina??o (R?) maiores do que 0,98, desvio relativos m?dios (E) inferiores a 6,5% em todos os tratamentos. O modelo do tempo de n-redu??o da taxa de desidrata??o se mostrou uma boa alternativa na defini??o do tempo de processamento das amostras submetidas ? desidrata??o osm?tica. Os valores de perda de ?gua variaram de 15,70 a 28,79% no tempo t(1/3), enquanto que para o tempo de t(m?dio) de 15,75 a 30,27% entre os tratamentos. O processo de desidrata??o osm?tica influenciou na qualidade final dos produtos, apresentando diferen?as significativas entre a fruta in natura e a processada para varia??o dos par?metros de cor, a capacidade antioxidante e a textura das amostras in natura e processadas.
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Desenvolvimento e aplica??o do teste desafio em refrigerante de laranja adicionado de concentrado de cenoura e ma?? / Development and application of microbiological challenge test (MCT) in orange soda added with carrot and apple concentrate

AZEREDO, Denise Rosane Perdomo 25 August 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-19T18:26:23Z No. of bitstreams: 1 2016 - Denise Rosane Perdomo Azeredo.pdf: 2006973 bytes, checksum: 610e1499e6733b78ee2eb47034198a7d (MD5) / Made available in DSpace on 2017-05-19T18:26:23Z (GMT). No. of bitstreams: 1 2016 - Denise Rosane Perdomo Azeredo.pdf: 2006973 bytes, checksum: 610e1499e6733b78ee2eb47034198a7d (MD5) Previous issue date: 2016-08-25 / Nowadays consumer desired healthy foods that promote benefits and free from food additives. The chemical composition of soft drinks, artificial colors and preservative, may pose a risk to consumer health due to the possibility of benzene formation, a recognized carcinogenic agent in humans and the association between artificial colors, allergic reactions and DNA damage. In this study, an orange soda formula containing the preservatives sodium benzoate and potassium sorbate with carrot and apple concentrate was developed. In parallel, we developed a standard formula containing tartrazine and sunset yellow. Physicochemical, microbiological and sensory analysis of formulas were carried out during the storage period of 150 days. It was observed that there were no changes in physicochemical parameters. However, the colorimetric analysis revealed a short shelf life in the sample containing the carrot and apple concentrate. Regarding microbiology, both formulations were according to regulation by public health agencies. The yeasts and molds counts presented 1 log cycle growth in the formula containing the carrot and apple concentrate, suggesting that the robustness of the developed matrix may be affected, if the hygiene conditions of processing line sanitation are not observed. It was found that the color was the sensory characteristic that most influenced consumers regarding the acceptability of the samples, signaling that this parameter interfered significantly in evaluating flavor and appearance The results obtained by microbiological challenge test and determination of growth potential (?) indicated that yeast and lactic acid bacteria are able to multiply in the formula containing carrot and apple concentrate without preservatives (? ? 0.5 log10), indicating that the formula is sensitive. Acid acetic bacteria, in these conditions, were inhibited. A preserved formula with the addition of carrot and apple concentrate and other formula with the addition of artificial colors were prepared. The results referring to the growth potential (?) indicated that yeast and lactic acid bacteria were inhibited (? ? 0.5 log10) in both formulas. However, the preservative resistant yeasts presented growth ability (? ? 0.5 log10). In the apple and carrot concentrate, it was observed that yeast, lactic acid bacteria and fungus Penicillium citrinum were inhibited, indicating that this ingredient should not be considered a nutrient source for microbial multiplication that would affect the formula robustness. It was verified the growth of the preservative resistant yeasts (growth potential ? ? 0,5 log10) in all the evaluated formulas and ingredient. The data obtained, in this study, indicate that the development of more natural foods still represents a challenge for the food industry. / Atualmente o consumidor anseia por alimentos mais naturais, saud?veis, que promovam benef?cios ? sa?de e que sejam isentos de aditivos. Nesse sentido, a composi??o qu?mica dos refrigerantes, especialmente no que concerne aos corantes artificiais e conservadores pode representar riscos ? sa?de do consumidor, devido a possibilidade de forma??o de benzeno, reconhecido agente carcinog?nico ao homem, e a associa??o entre corantes artificiais, rea??es al?rgicas e efeitos delet?rios ao DNA. Nessa pesquisa, inicialmente, desenvolveu-se uma formula??o de refrigerante de laranja, contendo os conservadores benzoato de s?dio e sorbato de pot?ssio, na qual os corantes artificiais ? amarelo tartrazina e amarelo crep?sculo foram substitu?dos por concentrado de cenoura e ma??. Em paralelo, desenvolveu-se uma formula??o controle. Foram realizadas an?lises f?sico-qu?micas, microbiol?gicas e sensorial das formula??es durante o per?odo de armazenamento de 150 dias. Observou-se o atendimento ao padr?o de identidade e qualidade e estabilidade das formula??es em rela??o aos par?metros f?sico-qu?micos. Entretanto, na an?lise colorim?trica observou-se uma degrada??o de cor percept?vel ao consumidor na amostra contendo o concentrado de cenoura e ma??. Em rela??o as an?lises microbiol?gicas, ambas as formula??es atenderam aos par?metros preconizados pela legisla??o. Entretanto, a contagem de bolores e leveduras apresentou crescimento de 1 ciclo log na formula??o contendo o concentrado de cenoura e ma??, sugerindo que a robustez da matriz desenvolvida pode ser afetada, se as condi??es de higieniza??o da linha de processamento n?o forem observadas. Em rela??o a an?lise sensorial, verificou-se que a cor foi a caracter?stica sensorial que mais influenciou os consumidores com rela??o a aceitabilidade das amostras, sinalizando que esse par?metro interferiu, de forma significativa na avalia??o do sabor e apar?ncia. Os resultados referentes a aplica??o do teste desafio e a determina??o do potencial de multiplica??o microbiana (?) indicaram que as leveduras e bact?rias l?cticas s?o capazes de se multiplicar na formula??o adicionada de concentrada de cenoura e ma?? sem conservadores (? ? 0,5 log10), sinalizando que a formula??o ? sens?vel. As bact?rias ac?ticas, nessas condi??es, foram inibidas. Nas formula??es preservadas quimicamente com adi??o de concentrado de cenoura e ma?? e a adicionada de corantes artificiais, os resultados referentes ao potencial de multiplica??o microbiana (?) indicaram que as leveduras e bact?rias l?cticas foram inibidas (? ? 0,5 log10) em ambas as formula??es. Entretanto, as leveduras resistentes a conservadores apresentaram habilidade de crescimento (? ? 0,5 log10). No ingrediente concentrado de cenoura e ma??, observou-se que as leveduras, bact?rias l?cticas e o fungo Penicillium citrinum foram inibidos, indicando que o concentrado n?o deve ser considerado uma fonte de nutriente para a multiplica??o microbiana que afetaria a robustez da formula??o. Constatou-se a multiplica??o das leveduras resistentes a conservadores, com potencial de multiplica??o ? ? 0,5 log10 em todas as formula??es e ingrediente avaliados. Os dados obtidos no presente estudo sinalizam que o desenvolvimento de alimentos mais naturais ainda representa um desafio para a ind?stria de alimentos.
177

G?nese e evolu??o do mestrado em ci?ncia da informa??o da Pontif?cia Universidade Cat?lica de Campinas / Genesis and evolution of the master in information science of the Pontifical University Catholic of Campinas

S?lvio, S?lvia Celeste 27 June 2005 (has links)
Made available in DSpace on 2016-04-04T18:36:26Z (GMT). No. of bitstreams: 1 Silvia Celeste.pdf: 596696 bytes, checksum: eb94349825782048efbb8455a6f8f594 (MD5) Previous issue date: 2005-06-27 / Pontif?cia Universidade Cat?lica de Campinas / This study presents the evolution of the Master Course in Information Science of PUC-Campinas, from 1977 to 2004. In this period, the course faced several changes, due to many factors as the recommendations of the national system of master and doctoral courses evaluation (CAPES), changes in the professors staff and also the influences of the development of the scientific area of Information Science. In the present research, the history of the course was based in the analysis of the official documents of the master course. Attention was paid to the profile of the students as well as of those that had concluded the course. As a consequence, comparisons may be enabled with other graduate courses in Information Science. In the same way, the gathered data may allow the development of policies for this scientific area. New perspectives may be identified not only for the PUC-Campinas Master course but also for the area of Information Science based on the present research. / A presente pesquisa configura-se como um estudo diacr?nico do percurso do Mestrado em Ci?ncia da Informa??o da Pontif?cia Universidade Cat?lica de Campinas, desde sua cria??o, em 1977, at? o ano de 2004. Nesses 27 anos, o Mestrado modificou por diversas vezes a proposta de curso, foi submetido a avalia??es peri?dicas pela Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, modificou a composi??o do corpo docente, promoveu um curso de especializa??o e um mestrado interinstitucional. Foi realizado o resgate da hist?ria do curso e sua evolu??o, tra?ado o perfil dos egressos e alunos matriculados e as denomina??es recebidas pelo Mestrado, atrav?s de pesquisa documental. Os dados contextuais e hist?ricos apresentados permitem fazer uma auto-avalia??o n?o apenas do Curso de Mestrado da PUC-Campinas, mas tamb?m da ?rea de Ci?ncia da Informa??o. Os dados obtidos permitem elaborar um desenho parcial da ?rea que poder? ser comparado com os demais programas de p?s-gradua??o em Ci?ncia da Informa??o do pa?s. Essa caracteriza??o pode fornecer subs?dios para elaborar ou redirecionar as pol?ticas de desenvolvimento da p?s-gradua??o da ?rea.
178

Contribui??o da tr?ade ci?ncia da informa??o, sistemas de informa??o e tecnologia da informa??o e comunica??o nas estrat?gias competitivas organizacionais: o setor moveleiro de Votuporanga

Silva, Marildo Domingos da 09 October 2006 (has links)
Made available in DSpace on 2016-04-04T18:36:29Z (GMT). No. of bitstreams: 1 Silva, Marildo Domingos.pdf: 4365984 bytes, checksum: 16ff3f37997272dee78ad1533c8caa81 (MD5) Previous issue date: 2006-10-09 / The importance of the triad: Information Science Information Systems and Information and Communication Technology in defining competitive strategies of the companies is a fact on the economical environment in the current days. This triad, along with Michael Porter's five competitive forces can create a significant difference during the stages of establishment and development or even cause the extinction of products and companies. We live in an Information Age which means that a focus on the information has become more and more important. Having the information is valuable to the companies. However knowing how to select, classify and store information besides creating agile mechanisms in order to recover it is something that can distinguish one company from another. The issue is about the tools and systems used capable of refining the information without losing its essence and mainly to spread it correctly in the right moment and to the right person. This research analysis the whole process from receiving to spreading the information connecting it with the companies competitive politics and also seeks to present an interface of its use sub utilization by management of furniture factories in Votuporanga a city in the state of S?o Paulo, Brasil / A import?ncia da tr?ade Ci?ncia da Informa??o, Sistemas de Informa??o e Tecnologia da Informa??o e Comunica??o na defini??o de estrat?gias competitivas empresariais ? fato no moderno ambiente econ?mico global. Esse conjunto, aliado ?s cinco for?as competitivas de Michael Porter, pode criar diferenciais determinantes para os est?gios de implanta??o, desenvolvimento ou mesmo de extin??o de produtos e empresas. As organiza??es vivem hoje a Era da Informa??o, fator que torna ainda mais reluzente o enfoque dado ? informa??o. No entanto, possuir informa??o ? algo de valor, mas ao selecion?-la, classific?-la, armazen?-Ia e ao criar mecanismos ?geis para recuper?-Ia, agrega-se um valor substancial, capaz de distinguir uma empresa da outra. O questionamento que se faz ? sobre as ferramentas e os sistemas utilizados, capazes de lapidar a informa??o, sem perder a sua ess?ncia e principalmente de difundi-Ia na forma, no momento e para a pessoa correta. Assim, o presente trabalho traz uma an?lise de todo o processo, que vai da capta??o ? divulga??o da informa??o, interligando-os ?s pol?ticas competitivas empresariais e busca tamb?m, apresentar uma interface de sua utiliza??o - ou subutiliza??o - pelo segmento empresarial das ind?strias moveleiras da regi?o de Votuporanga.
179

Contribui??o da ci?ncia da informa??o para cria??o de um plano de seguran?a da informa??o / Contribution of information technology to the creation of the information security plan

Ramos, Isa?as de Queiroz 27 February 2007 (has links)
Made available in DSpace on 2016-04-04T18:36:29Z (GMT). No. of bitstreams: 1 Isaias de Queiroz Ramos-1.pdf: 1214882 bytes, checksum: 5f1bab228014fa339de2ae8e9b55cd31 (MD5) Previous issue date: 2007-02-27 / Every day companies deal with information which has different values in the business world. Both, the strategic information and the information that supports decisionmaking need management and confidentiality warranty, integrity as well as availability. Therefore, the aim of this paper was to analyse the contribution of Information Technology to the creation of the Information Security Plan. A bibliographic research analysing the concepts of organization, information, Information Science, Strategic Planning and information security was used to carry out this paper. By evaluating the information flow in the organizations, it was possible to extract not only the information needs but also the application of the characteristics and protection domain, the generation of the need of qualified and high-priority information as well as the use of the norm NBR/ISSO 17799:1 in the organizational environment. This study certified the need of subsidies to the creation of an Information Security Plan which must be integrated with ways of dealing with information conceived by Information Technology and by management techniques used in the process of Strategic Planning. / As organiza??es lidam diariamente com informa??es que t?m assumido valores distintos no mundo dos neg?cios. As informa??es consideradas estrat?gicas e de apoio ?s tomadas de decis?o necessitam de gerenciamento e garantia de confidencialidade, integridade e disponibilidade. Sendo assim, este trabalho teve como objetivo analisar a contribui??o da Ci?ncia da Informa??o para cria??o de um Plano de Seguran?a da Informa??o. Para isso, utilizou-se de uma pesquisa bibliogr?fica, analisando os conceitos de organiza??o, informa??o, Ci?ncia da Informa??o, Planejamento Estrat?gico e seguran?a da informa??o. E, ao avaliar os fluxos de informa??es nas organiza??es, foi poss?vel extrair as necessidades de informa??es, como tamb?m a aplica??o das caracter?sticas e dom?nio de prote??o, a gera??o da necessidade de informa??es qualificadas e priorizadas e a utiliza??o da norma NBR/ISO 17799:1 no ambiente organizacional. Assim constaram-se, com esse estudo, subs?dios necess?rios para cria??o de um Plano de Seguran?a da Informa??o que seja integrado com as formas de tratamento das informa??es, concebidas pela Ci?ncia da Informa??o e pelas t?cnicas de gest?o utilizadas no processo de Planejamento Estrat?gico.
180

Institucionaliza??o da pesquisa cient?fica: estudo do repert?rio metodol?gico das disserta??es defendidas em dois Cursos de P?s-Gradua??o em Ci?ncia da Informa??o no Brasil / Scientific research institutionalization: a study of the methological repertoire in dissertations developed in two post-graduation courses in Information Science in Brazil

Oliveira, Mara Jana?na de 11 February 2008 (has links)
Made available in DSpace on 2016-04-04T18:36:36Z (GMT). No. of bitstreams: 1 Mara Janaina OLIVEIRA.pdf: 802686 bytes, checksum: d15854df9481c0443b29f688e564236e (MD5) Previous issue date: 2008-02-11 / The research has the objective to investigate the cognitive institutionalization of the scientific research in Information Science in Brazil, from the methodological repertoire analysis of the dissertations developed in two post-graduation courses, from 1993 to 2005. The specific objectives are: identify and describe the methodological repertoire used by the dissertations authors and identify the thematic tendencies. It is characterized as an exploratory and descriptive study, supported by tools and techniques of the methods of the analysis of the contents and scienciometric. The empiric corpus is constituted by 255 dissertations, 73 of them are documents from Universidade de S?o Paulo (USP) and 182 of them are from Pontif?cia Universidade Cat?lica de Campinas (PUC-Campinas). The analysis of the graphic representations supported by the theoric conception brought the following results: the dissertations developed in the IS post-graduation courses in PUC-Campinas and USP follow the same tendencies of others research programs of IS in Brazil. The dissertations are characterized by their methodological plurality and they are directed to practice, appliance, or solution of specific and located problems. It can also be observed that there are little reflexion and explanation about the repertoire adopted in these researches. As well there is a lack of understanding about what are the types of researches, methods and techniques. The more commonly used method in theses dissertations is the case study with a pragmatic focus and with a quantitative nature, in place of theoric and conceptual researches that are very important to the cognitive institutionalization of this area. / A pesquisa tem como objetivo investigar a institucionaliza??o cognitiva da pesquisa cient?fica em Ci?ncia da Informa??o no Brasil, a partir da an?lise do repert?rio metodol?gico das disserta??es defendidas em dois Cursos de P?s-Gradua??o, no per?odo de 1993 a 2005. Os objetivos espec?ficos s?o: identificar e descrever o repert?rio metodol?gico utilizado pelos autores das disserta??es e identificar as tend?ncias tem?ticas. Caracteriza-se como um estudo explorat?rio e descritivo, apoiado pelas ferramentas e t?cnicas dos m?todos de an?lise de conte?do e cienciom?trico. O corpus emp?rico ? constitu?do por 255 disserta??es, sendo 73 documentos referentes ? Universidade de S?o Paulo (USP) e 182 ? Pontif?cia Universidade Cat?lica de Campinas (PUC-Campinas). As an?lises das representa??es gr?ficas apoiada pelo quadro te?rico, geraram os seguintes resultados: - as disserta??es defendidas nos Cursos de Mestrado em CI da PUC-Campinas e da USP seguem algumas tend?ncias das dos demais programas de pesquisas em CI no Brasil. As disserta??es est?o caracterizadas por pluralidade metodol?gica e orientadas para a pr?tica, aplica??o ou solu??o de problemas espec?ficos e localizados. Observa-se ainda, pouca reflex?o e explica??o sobre o repert?rio metodol?gico adotado nas pesquisas. Assim como h? falta de entendimento do que sejam tipos de pesquisa, m?todos, t?cnicas. O m?todo mais utilizado nas disserta??es, realmente, ? o estudo de caso com enfoque pragm?tico e de natureza quantitativa, em detrimento de pesquisas te?ricas e conceituais que s?o de suma import?ncia para a institucionaliza??o cognitiva da ?rea.

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