Últimos itens adicionados do Acervo: Universidade Tecnológica Federal do Paraná

A Universidade Tecnológica Federal do Paraná (UTFPR) é uma universidade pública mantida pelo governo federal e sua sede esta localizada na cidade de Curitiba, capital do estado brasileiro do Paraná.

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‣ Melindrosas e garotas: representações de feminilidades nos traços de J. Carlos (1922-1930) e Alceu Penna (1938-1946)

Mannala, Thaís
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
In the present work femininity representations will be analyzed in two separate journals: the Flappers in the magazine Para Todos... and the Garotas column in the magazine O Cruzeiro. The cuts include the period from 1922 to 1930 for the Flappers and 1938-1946 for Garotas, favoring to a sequence of subsequent decades, in order to understand how representations of femininity have changed or remained. We also want to investigate how the mood and visuality contributed to standardize roles and relationships between gender, together with public policy. Magazines aimed to bring identification with hierarchized speeches, acting as gender pedagogy. However, we notice that humor sought in the fissures of the representations, the double standard, in which women were negotiated spaces of action and freedom. Both the Flappers and the Garotas used tactics to convince and seduction that led them to grant wishes and achieve some of their goals. They questioned and emphasized the contradictions and tensions of their respective decades. Sometimes indicated pretexts to think about the social changes of behavior and how men were placed in this board.; CAPES; No presente trabalho serão analisadas representações de feminilidades em dois periódicos distintos: as Melindrosas na revista Para Todos... e a coluna Garotas na revista O Cruzeiro. Os recortes compreendem os anos de 1922 a 1930 para as Melindrosas e de 1938 a 1946 para as Garotas...

‣ Coisa de macho: representações de masculinidades em uma barbearia curitibana

Morais, Vinícius Miranda de
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
My goal in this dissertation is to expose the imbrications between material culture and gender relationships by approaching the construction of depictions of masculinities at store environments designed exclusively for male customers. The scope of study is centered on the advertising and interior design projects of Barbearia Clube, opened in Curitiba in 2007. The planning of these projects hinged on a masculinity ideal called “classic man”, presenting features such as “manly”, “traditional” and “with no frills”, which became the foundation for the development of the barber shop’s communication signs and decoration. The analysis of the advertising and interior design projects is carried out through statements obtained in interviews with the persons involved in the projects, the assessment of images applied in Barbearia Clube advertisement pieces, as well as images obtained by photographic process in visits to the premises. With this analysis I aim to expose the social construct character from gender prescriptions as well as the fundamental role of artifacts in the construction of subjects and their identities.; CAPES; Neste trabalho tenho como objetivo evidenciar as imbricações entre cultura material e as relações de gênero...

‣ Harmonia cromática em animações: a cor no contexto da tecnologia

Franck, Gláucia
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
This paper search is to demonstrate the reciprocal influence between art and technology in addition to the artifact through the use of color in obtaining the chromatic harmony and strengthening visual perceptual and cultural. We try to show how the art appropriates technology in obtaining harmony by using the color in the creative process. The art, to be mediated by technology, challenges the artist to oppose technological determinism that imposes results by standardization of the use of its gadgets, surpassing its limits in reinvention of their purposes. This work has as objective find the choices and the uses of color in the animation short films of Disney-Pixar’s as materialization of meanings in the construction of a narrative, highlighting the opposition between the relational context and instrumental of technology by overcoming its limits reinvented itself by using the color in order to reinforce the meanings offered by this narrative. Initially we will be presenting assumptions likely to find technology in their conceptual dimensions starting from the axis color that permeates throughout the work, the main focus will be on the concepts of the theory of color essential for to this understanding, and finally, armed with the theoretical framework...

‣ Estudo comparativo das aplicações dos objetos de teste Eurospin e American College of Radiology no controle de qualidade em ressonância magnética

Krzyuy, Ariadne Maria
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
Magnetic resonance imaging (MRI) is a method of diagnostic imaging which has advantages over other methods, which caused the number of installed equipment in the large Brazilian centers increased 88% over the past 5 years and about 508% in the last 15 years, which shows the importance of this method as a diagnostic imaging modality. To ensure medical imaging with diagnostic quality, it is necessary that the equipment is monitored for quality of the images they produce. Therefore, in order to maintain the quality of medical images at the highest level and ensure the proper performance of equipment, are implemented Quality Control (QC) programs in MRI. In Brazil, there are few works published discussing the procedures for the QC in MRI and there are no national standards for its regulation. The standardization and recommendation on QC in MRI is restricted to the work of international organizations. The best-known commercially available test objects are the test object (TO) Eurospin and the American College of Radiology (ACR), and several international research groups have published studies on QC in MRI with promising results using these objects. The aim of this work is to study the methodology of use of the test objects Eurospin and ACR...

‣ Gerenciamento de resíduos sólidos urbanos: estudo de caso no município de Pato Branco – PR

Starck, Keli
Fonte: Pato Branco Publicador: Pato Branco
Tipo: Dissertação de Mestrado
Português
The solid waste management is a topic much discussed today, this is due to the fact that we have a significant increase in production of solid waste which, when improperly disposed, are polluting sources of air, soil and water. The need to properly manage municipal solid waste evolved quickly and progressively, making it a challenge for society and public administration. In order to contribute to the discussion, this thesis was to analyze the municipal solid waste management process adopted by the city of Pato Branco - PR and its adaptation to the current legislation. This work was methodological basis a case study in qualitative research employing techniques of collecting primary and secondary data. Considering the results obtained through visitation and observation, interviews and questionnaires, it is possible to find what the status of implementation of existing legislation, especially the Política Nacional de Resíduos Sólidos (Law nº 12,305/2010). Despite identify important advances in the city studied, especially in the collection of solid waste and disposal in landfill, there are still two outstanding issues, which relate to remediation of environmental liabilities of the old landfill and performing the composting of organic waste. It points out therefore that the advance in the management of appropriate solid waste is related to the implementation of public policies and the sharing of responsibilities between all actors involved.; CNPq; CAPES; O gerenciamento de resíduos sólidos é um tema muito abordado atualmente...

‣ Um estudo sobre a rotatividade de pessoal entre profissionais de empresas brasileiras de desenvolvimento de software

Frufrek, Guilherme Luiz
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
Employee turnover is one of the major challenges for many software development companies. This work presents a study to identify the main causes and effects of employee turnover among professionals of Brazilian software development companies. Strategies applied to minimize employee turnover and its effects were also investigated. A survey methodology was used to collect data from software development professionals. Data collection was performed using the technique of questionnaire with closed questions using five-point Likert scale and multiple choice questions. Cronbach’s alpha coefficient was applied to check the reliability of the answers. The analysis of data from 67 respondents was conducted through descriptive statistics and inferential statistics. The results indicate that inappropriate management style, personal expectation not achieved within the company, lack of professional recognition, and lack of organizational involvement influences the decision of professionals to leave the company. These factors can contribute decisively in rates of employee turnover. The results also indicate other aspects, related to the employee, which are important for turnover intention. The company must be concerned with factors that can motivate the employee to stay with the company...

‣ Técnicas fuzzy aplicadas ao controle descentralizado

Almeida, João Paulo Lima Silva de
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
This work presents a research proposal for the control of multivariable systems using fuzzy logic. This proposal consists in developing a control system with two inputs and two ouputs. It is presented the main structural and technological aspects of the developed system as well as the fundamentals of fuzzy control, including its main derivations, namely Fuzzy-PD, Fuzzy-Incremental, Fuzzy-PD+I. Still, it is considered the use of a fuzzy-P+I topology, which stands for the reduced number of rules. Fuzzy-P+I. Decentralized control strategies are considered. The control structures are implemented in the hardware CompactRIO R together with the LabVIEW R evelopment software, with the aim of controlling the fluid level and temperature in a tank of the didactic plant.; Este trabalho apresenta uma contribuição à área de controle de sistemas multivariáveis com a utilização de lógica fuzzy. Esta proposta consiste no desenvolvimento de um sistema de controle com duas entradas e duas saídas. São apresentados os principais aspectos estruturais e tecnológicos do sistema desenvolvido, assim como os fundamentos da estratégia de controle fuzzy, incluindo suas principais derivações, a saber, Fuzzy-PD, Fuzzy-Incremental, Fuzzy-PD+I. Ainda...

‣ Controle neural aplicado a um conversor boost utilizado em aerogeradores de baixa potência

Tonon, Thiago
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
This work presents the study, design and simulation of a DC boost converter with output voltage control using neural networks. The boost converter studied in this work is being used in a wind turbine low power, with maximum power of 3kW. Due to the operation of the variable speed of the wind turbine, the input voltage of the converter is also variable over a wide operating range, and the output must be stabilized to a fixed voltage. This means that there is a need to control the converter so that differences in input voltage are compensated. To compensation this difference, a controller was designed using the root locus method. The modeling of the boost converter is also presented. The controller provides the time of operation of power semiconductor switch used in the converter, thereby controlling the output voltage. The variation in input voltage, which can vary from 50V to 350V, makes the driver does not act optimally for all operating points. Thus, a neural controller is designed to work as a controller, compensating disturbances of the converter input voltage. The validation of this controller was performed by simulation using Matlab / Simulink software, to confirm the theoretical development presented in the work.; Fundação Araucária; Este trabalho apresenta o estudo...

‣ Estudo e projeto de controladores aplicados na malha de controle de corrente de um filtro ativo de potência paralelo

Malvezzi, Victor Belieiro
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
This work presents the study, design and implementation of three control strategies for compensating current in a single-phase Shunt Active Power Filter (SAPF), such as the conventional PI controller based on reference frame ( ), conventional PI controller based on reference frame ( ), PI plus resonant controller based on reference frame ( ) and PI plus resonant controller based on reference frame ( ). The DC bus voltage is controlled by using a linear PI controller. The SAPF consists of a full-bridge inverter connected to the grid. The main function of the shunt SAPF is to provide to the utility grid an adequate compensation current, containing the same amplitude and opposite phase of the load current harmonics. The algorithm used for obtaining the reference compensation current is based on the synchronous reference frame (SRF algorithm). Mathematical analyzes are developed in order to obtain the mathematical model which represents the SAPF physical system. In addition, it is presented a design methodology employed for obtaining the gains of the PI controllers used in both the compensation current and the DC-bus voltage loops. It is also presented methodology for tuning the resonant controllers. Simulation and experimental results are presented to validate the theoretical development and compare the performance of FAPP when submitted to the proposed control strategies.; Este trabalho apresenta o estudo...

‣ Classificação de falhas em maquinas eletricas usando redes neurais, modelos wavelet e medidas de informação

Silva, Lyvia Regina Biagi
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
This work presents a methodology for diagnosis and classification of faults in three-phase induction motors connected directly to the power grid. The proposed method is based on the analysis of the stator current signals, with and without the presence of faults in the bearings, stator and rotor. These faults cause the presence of specific frequency components that are related to the machine rotational speed. The signals were analyzed using wavelet-packet decomposition, which allows a multiresolution evaluation of the signals. Using this decomposition, we estimated some predictability measures, such as relative entropy, predictive power and normalized error variance, obtained with the predictability component analysis. With this measures, we verified which were the most predictable components. In this work, normalized error variance and the predictive power were used as inputs to three topologies of artificial neural networks used as classifiers: multilayer perceptron, radial basis function and Kohonen self-organizing maps. We tested six different input vectors to the artificial neural networks, in which we vary the predictability measures and the number of elements of the vectors. The studies were performed considering samples of signals from different motors...

‣ Otimização de parâmetros via metaheuristicas populacionais e validação de um controlador de estrutura variável

Bertachi, Arthur Hirata
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
This work presents the application of particle swarm optimization and ant colony optimization in the parameters optimization of a non-linear controller with variable structure based on generalized minimum variance control. This controller is composed of two parts: linear and non-linear. The non-linear term of the controller consists of two parameters that directly affects the control action, and are obtained by trial and error. Metaheuristic methods were applied to find out the optimized values of these parameters. The cost function used in metaheuristic methods takes account the error and the control signal. A numerical example of the design of this controller is also presented. Three practical experiments were considered: a servomechanism velocity control and two control loops in a didactic industrial plant, level and flow control. Experimental results emphasize the improvement of the system performance when the optimization methods are applied. A comparision with PI controller is shown.; CAPES; Este trabalho apresenta a aplicação dos métodos de otimização por enxame de partículas e por colônia de formigas na otimização dos parâmetros de um controlador não linear de estrutura variável baseado em um controlador de variância mínima generalizada. Este controlador é composto por duas parcelas distintas: uma parcela linear e outra não linear. A parcela não linear do controlador apresenta dois parâmetros que afeta diretamente o comportamento do controlador e tais parâmetros são obtidos de maneira empírica. As metaheurísticas foram aplicadas para se obter os valores otimizados destes parâmetros. Foi considerada uma função custo que leva em consideração o erro de rastreamento e a variação da ação de controle. Um exemplo numérico do projeto deste controlador também é apresentado. O controlador otimizado foi experimentado em três plantas reais: controle de velocidade de um servomecanismo...

‣ Estabilização de um sistema com histerese e sujeito a falhas aleatorias

Huamaccto, Elmer Lévano
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
This note presents conditions to assure the stability in probability for a hysteresis Bouc-Wen model controlled by a proportional-integral controller subject to random failures in the transmission line. When a failure happens, the controller turns off and remains off for a while. After that, the controller turns on and keeps working until the occurrence of the next failure. The failures occur according to a Poisson distributed process. A numerical example illustrates the result. A real application considering the speed control of a DC motor is presented.; Este trabalho apresenta condições suficientes para garantir a estabilidade em probabilidade para um sistema com histereses, modelado pelas equações de Bouc-Wen, mediante um controlador proporcional integral sujeito a falhas aleatórias. Quando ocorre uma falha de forma aleatória na linha transmissão, o sistema desliga o controlador e fica assim por um tempo. Após esse tempo, o sistema liga novamente o controle e permanece ativo até a próxima falha que ocorre de forma aleatória. As falhas ocorrem de acordo com o processo de distribuição de Poisson. Uma aplicação real considerando o controle de velocidade de um motor DC é apresentado.

‣ Avaliação dos esforços cisalhantes em parafusos fixadores de vigas de estrutura de madeira

Tonon, José Ernesto
Fonte: Cornelio Procopio Publicador: Cornelio Procopio
Tipo: Dissertação de Mestrado
Português
In most constructions are used wooden structures for roofs and many are executed in the conventional system using trusses. With the advancement of architecture, with regard the employability of timber, other ways have been used making the free and harmonious environment, and for this, the need for larger beams, to win larger spans. Therefore, the materials of the structural elements have an important role in order to demand continuity of parts with in the safety standards. Brazilian Standards of forms of links where the use of timber and steel, ensure stability for both materials, as the use of bolts and pins as liaison, used in buildings. In this paper, the proposal is to assess the joint of bolted connections materials between timber / timber and compare it with the connections timber / steel plate / timber; the folded plate and cold pressed between the parts is not apparent. Therefore, the connection will fall on the bolts, but with the plate resistance will be higher by supporting the shearing caused by the bending of the bolts and inserted directly on timber, which is very important as to the direction of the fibers and of the applied load.; Na maioria das construções utilizam-se estruturas de madeira para coberturas e muitas são executadas no sistema convencional...

‣ Uso de invertebrados aquáticos na avaliação da toxicidade da água e do sedimento contaminados por efluentes de esgoto doméstico

Tulio, Juliana
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
In Brazil the environmental law in force establishes that wastewaters can not cause acute or chronic effect to the water bodies’ biota. In the present study were evaluated the ecotoxicological effects of surface water and whole sediment samples, from three sites located nearby a wastewater treatment plant, that were collected from a river in the region of Curitiba, state of Paraná. The samples were submitted to acute and chronic toxicity tests, utilizing the aquatic invertebrates D. magna and C. sancticaroli. Besides the ecotoxicological tests, BOD, COD, Total Phosphorus, Total Nitrogen Ammonia and Thermotolerant coliforms were measured from the surface water samples. The whole sediment composition was evaluated by Energy-dispersive X- Ray Fluorescence Spectrometry (EDXRF) to determine chemical elements present in these samples. The BOD, COD, Total Phosphorus, Total Nitrogen ammonia, and Thermotolerant coliforms analysis’ results possibly demonstrated surface water contamination by domestic sewage, for the samples analyzed in 3 campaigns. The sediment composition is compatible with the kinds of soils present in the respective sites, however there were quantitative variation of chemical elements during the campaigns, such as silicon...

‣ Avaliação da biodisponibilidade e a bioacumulação de metais em botos-cinza do complexo estuarino-lagunar de Iguape-Cananéia, SP

Salgado, Lilian Dalago
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
The Ribeira de Iguape river is the most responsible for the input of freshwater and sediments in suspension to the Estuarine-Lagoon Complex of Iguape-Cananéia (CELIC), which has a population of about 200 Guiana dolphins. The basin of this river was strongly affected by mining activities, which contaminating the sediments along its course and in part of the estuary. This study evaluated the spatial and temporal variation of physical and chemical parameters of the environment, the bioavailability of Fe, Zn, Mn, Co, Cu, Cr, Cd, Pb and Ni in the sediments and the accumulation of these elements in the liver of 21 dolphins of the species Sotalia guianensis. The water and sediment were sampled in 8 points throughout the system in three different samples between the years 2013 and 2014 and the tissue samples were obtained by monitoring of the beaches between 2009 and 2012. The trophic conditions found between the portions differ in great degree, most notably salinity, resistivity,DO, pH and the supply of nutrients and metals. The metals Pb, Zn, Cu, Mg and Fe showed high values in sediments near Iguape, being considered as strong bioavailable. The SEM/SVA reason for the metalic ions Pb, Cd, Ni, Cu and Zn showed greater toxicity of the sediments in this region. There were positive correlations between these elements indicating that they probably have the same sources...

‣ Aplicação e avaliação de técnicas de agroecologia e compostagem como dinamizadores da educação ambiental nos currículos e espaços escolares

Mello Filho, Nilson Ramos de
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
This dissertation present one proposal to develop and implement teaching situations, using composting and agro ecology as a dynamic way to environmental education in the school resume, in two municipal schools from Pinhais, Paraná. Searching to form future citizens responsible and compromised with the destiny and the environmental quality of the community that they live, have been develop themes of practice application of composting and the principles of agro ecology as dynamic ways to the environmental education. This themes were explore in a transversal way looking the holistic approaching of the men relation, nature and society. The treated themes were: composing – using tree different techniques; teaching methodology – apply learning as beans germination; caring about the mothers present – vessels of spice; and organization the school gardem. Each methodology was develop with the elementary school classes, in two municipal schools from Pinhais, totalizing 805 students and 49 teachers acting in the process. Have been realized a survey about the resume contends and their respective knowledge area, in the elementary teaching in the municipality of Pinhais, trying to found the relations between the transversal themes and how it could be work in an interdisciplinary way . As a result was noted that the composing techniques using cages have been the ones that have better adapted to the school dynamic...

‣ Avaliação de programas de educação ambiental voltados para gestão de resíduos sólidos em escolas municipais de Pinhais/PR

Scupino, Flavia
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
The main goal of this study is to evaluate environmental education programs for managing solid waste in municipal schools in Pinhais / PR. The programs are related to the campaign "Stop the Waste" and to the project "100% Recyclable School", which, until this moment, have not undergone any type of evaluation to assess the extent of its goals. The field survey and the case study outlined the exploratory research. The field survey was developed with employees (qualified informants) of the Education Departments of the Environment and the municipal Urbanism of Pinhais, directly involved in the management of these programs. The case study was developed in Municipal Schools, Aroldo de Freitas and 31 de Março, together with the teachers and students of 4th and 5th grades of Elementary School. The qualitative and quantitative method was used for applying survey questionnaires in the secretariats and in the case study schools, in order to evaluate and investigate the knowledge of the subjects regarding these programs. The survey responses were grouped into categories and thus could be translated into percentage data. The solid waste segregation conducted by quartering technique was used to identify qualitative and quantitative solid waste produced in the case study schools. The results obtained by questionnaires applied together with qualified informants demonstrated little knowledge of the programs. The results of the solid waste segregation proved that recyclable and organic waste were found completely mixed. The results of the questionnaires with teachers and students in the 4th and 5th grades showed that the actions of the project "100% Recyclable School" showed better results than the campaign "Stop the Waste"...

‣ Identificação de bactérias láticas deteriorantes e avaliação do efeito inibitório de nisina e pediocina em presunto cozido fatiado embalado a vácuo

Kalschne, Daneysa Lahis
Fonte: Medianeira Publicador: Medianeira
Tipo: Dissertação de Mestrado
Português
Esta dissertação é composta por 2 artigos. Referências disponíveis ao final de cada artigo.; INTRODUCTION AND AIMS ─ In processed cooked meat products most of the microbiota is inactivated by heat application process which simulate a pasteurization. These products also receive additives in composition that generate inhibitory effect on the certain microorganisms groups growth. With the reduce of pathogenic microorganisms on vacuum packed or modified atmosphere samples, conditions are created for the lactic acid bacteria (LAB) growth, as described Gram positive, non-spore forming, catalase negative, devoid of cytochromes, facultative anaerobic, fastidious, mesophilic, acid tolerant, strictly fermentative metabolism that produce lactic acid as the major end product of fermentation of carbohydrates. The development of these microorganisms causes aroma, flavour and appearance undesirable in meat products. In view of these considerations, the aim of this work was to evaluate the LAB inhibition growth in samples of sliced vacuum-packed cooked ham, by the application of bacteriocins. Specific aims included: the quantification and identification of species of predominate LAB in the samples of sliced vacuum-packed cooked ham; the study of the ingredients of the formulation of cooked ham combined with nisin and pediocin conducted in Man Rogosa and Sharp (MRS) broth using a strategy of experimental design combined with predictive microbiology on evaluation of Lactobacillus sakei growth; and a validation of results obtained in MRS broths on food matrix by the elaboration of three formulations involving the use of nisin and a control formulation...

‣ Gestão de custos como instrumento de governança pública: um modelo de custeio para os hospitais públicos do Paraná

Blanski, Márcia Beatriz Schneider
Fonte: Curitiba Publicador: Curitiba
Tipo: Dissertação de Mestrado
Português
Cost management brings about several benefits to any type of organization, such as the certainty that resources are well managed, but it is not much used by the public hospital sector, what is a paradox seeing that hospital management is complex and public health faces an under-financing situation. Based on the aforementioned facts, the present study aims at answering the following question: What is the contribution of costing models to public governance in the State of Paraná public hospitals? So, the study objective is to propose a costing management model addressed to improve health strategy control, transparency, budget and planning actions in public hospitals directly managed by the State of Paraná. Since the hospital sector is complex, our study is highly relevant as a helping tool to: investment decision-making processes, changes of healthcare profile, use of spare capacity and service improvement, among others. Considering the universal rights ensured by the Brazilian Federal Constitution, the country public health system needs to show maximum efficiency. In addition to hospital complexity, the sector increased costs are justified by the change of demographic and epidemiological profiles, Brazilian population aging, chronic disease growth...

‣ Obtenção e caracterização de amido de mandioca (Manihot esculenta Crantz) modificado com ácido tartárico

Viell, Franciele Leila Giopato
Fonte: Campo Mourao; Medianeira Publicador: Campo Mourao; Medianeira
Tipo: Dissertação de Mestrado
Português
The chemical modification of native starch cause structural changes in the polymer molecule affecting their physic-chemical properties which make them suitable for various industrial uses. Tartaric acid is an organic dicarboxylic acid which can chemically modify the starch structure and its use is allowed in foods. In this study, the tapioca starch was modified with tartaric acid and the effect of acid concentration (4.5 to 8.0 g.100g-1) and the reaction pH (5.0 to 8.0) on the properties starch were evaluated using a 22 face-centered central composite design. The physico-chemical properties, functional, and pasting properties were determined. The infrared spectra Fourier transform (FT-IR) and the morphology of granules by scanning electron microscopy (SEM) was also evaluated. The modification reduced the intrinsic viscosity and the amylose contents with the increase of the acid concentration and decrease of pH. At pH 5.0, there was a higher percentage of mono tartarate ester and higher swelling and solubility of starches were observed. At pH 6.5 and 8.0, the modification caused a reduction in the swelling and solubility, increased resistance to freeze-thaw and improvement in the pasting properties (increased thermal and mechanical resistance). FT-IR confirmed qualitatively the esterification of starch by the appearance of bands attached to ester groups in the tests performed at pH 5.0. The modification did not cause obvious changes in the external morphology of the starch granules as observed by MEV. It was possible to conclude that the effect of acid concentration on the properties of the starch was less than the effect of pH where lower pH values favor the esterification of starch and higher pH values favor the crosslinked.; CAPES; As modificações químicas do amido nativo causam alterações estruturais na molécula do polímero afetando suas propriedades físico-químicas o que os torna aptos para vários usos industriais. O ácido tartárico é um ácido orgânico dicarboxílico que pode modificar quimicamente a estrutura do amido e tem uso permitido em alimentos. Neste estudo...