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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

Produção e descarte de óleo residual de fritura na cidade de São Paulo/SP: proposta para uma gestão integrada com auxílio das geotecnologias / Production and disposal of residual frying oil in the city of São Paulo/SP: proposal of integrated management with aid of geotechnologies

Gustavo Morini Ferreira Gândara 11 March 2016 (has links)
O município de São Paulo detém uma grande quantidade de fontes produtoras de óleos e gorduras residuais, que são aproximadamente 13.000 estabelecimentos. O potencial poluidor desses resíduos é imenso, faz-se necessário um programa funcional, sustentável e integrado de coleta e destinação correta para o óleo e a gordura descartados. Nesse sentido, a geografia, como ciência da sociedade e da natureza utiliza-se de diferentes métodos, técnicas e metodologias para avaliar os problemas e auxiliar na criação de propostas que visem minimizar os impactos ambientais causados pelo inadequado descarte dos resíduos. O objetivo desse trabalho é avaliar como é realizado o descarte do óleo residual de fritura na cidade de São Paulo e dar sugestões para a geração de uma política pública integrada de identificação dos focos geradores, coleta e destinação adequada desses resíduos. O descarte de óleos e gorduras residuais em locais inapropriados, prática comumente utilizada por estabelecimentos comerciais, pode causar inúmeros impactos prejudiciais ao meio ambiente, impactos estes que vão desde poluição dos mananciais e solos até obstrução e entupimentos de redes coletoras de esgoto, ocasionando gastos desnecessários ao setor público. O aumento do número de estabelecimentos geradores de óleo residual de fritura na cidade de São Paulo gera também uma maior pressão sobre os sistemas de coleta de esgoto, pois a prática do descarte incorreto desses resíduos é muito comum e causa sérios problemas de entupimento e mau cheiro. Assim, esta pesquisa busca, através do uso de geotecnologias para análise do uso da terra, avaliar como se deu o processo de ocupação urbana ao longo dos anos, e identificar as áreas onde ocorreu um maior crescimento do número de estabelecimentos geradores de gordura residual. Este trabalho pretende contribuir para a conscientização da população, empresários, empreendedores e gestores públicos quanto à problemática do descarte incorreto de óleos e gorduras residuais, criando uma cultura positiva, capaz de envolver a todos esses agentes, levando a uma política sustentável sobre esse assunto. Após um levantamento das políticas vigentes no município de São Paulo, relacionadas com os óleos residuais, verificou-se que existe apenas uma norma que regulamenta a coleta e o rerrefino de lubrificantes para máquinas em geral. A lei foi estabelecida pelo CONAMA (Conselho Nacional do Meio Ambiente) Lei nº 6.938 de 31 de Agosto de 1981 e regulamentada pelo Decreto nº 99.274 de 06 de Julho de 1990, propiciando a criação de uma rede regulamentada de iniciativa particular visando o rerrefino desses resíduos. Iniciativas como as da cidade de São Francisco (EUA), voltadas especificamente para os óleos e gorduras residuais de fritura, poderiam ser adotadas facilmente no município de São Paulo, exigiria apenas um esforço conjunto entre secretarias e a adoção de um sistema de informações geográfica (SIG), no qual fossem carregadas as bases necessárias para determinar os pontos produtores de óleo residual e o volume de descarte de cada estabelecimento. Com o cruzamento dessas informações seria possível determinar os pontos mais críticos do município, por onde o trabalho de coleta deveria ser iniciado, passando a atender todo o território ao longo da implantação do projeto. A adoção de políticas como essas beneficiam todos os munícipes, além de melhorar a qualidade ambiental das áreas urbanas, evitando, assim, gastos excessivos com a manutenção das tubulações, transtornos para os cidadãos, agravamento de problemas de saúde pública, como as pragas urbanas e criando, mecanismos necessários para uma cidade sustentável. / The municipality of São Paulo holds a lot of producing sources of residual oils and fats, which are approximately 13,000 establishments. The pollution potential of this waste is immense; it is necessary a functional program, sustainable and integrated to the collection and proper disposal for oil and fat discarded. In this sense, geography, as a science of society and nature makes use of different methods, techniques and methodologies to assess the problems and assist in the creation of proposals to minimize environmental impacts caused by improper disposal of waste. The aim of this work is to evaluate how it is done the disposal of residual frying oil in Sao Paulo and give suggestions for the creation of an integrated public policy to identify the generators outbreaks, collection and proper disposal of such waste. The disposal of residual oil and fat in the wrong places, a common practice used by commercial establishments, can cause a lot of harmful impacts to the environment, ranging from water and soil pollution to obstruction and clogging of sewage systems, causing unnecessary expenses the public sector. The increase of residual frying oil generators in Sao Paulo also generates greater pressure on the sewage collection systems, because the incorrect disposal practice of this waste is very common and cause serious clogging problems and bad smell. Thus, this research aims, through the use of geo-technologies for analysis of land use, evaluate how was the process of urban settlement over the years, and identify areas where there was a greater increase in the number of generators establishments residual fat. This work aims to contribute to public awareness, businessmen, entrepreneurs and public officials about the problem of incorrect disposal of residual oil and fat, creating a positive culture, able to involve all these agents, leading to a sustainable policy on the subject. After a survey of existing policies in the São Paulo municipality, related whit residual oils, it was found that there is only one norm that regulates the collection and re-refining of lubricants for machines in general. The law was established by CONAMA (National Environment Council) Law No. 6938 of August 31 of 1981 and regulated by Decree No. 99.274 of July 6 of 1990, allowing the creation of a regulated network of private initiative aimed the re-refining of such wastes. Initiatives such as the city of San Francisco (USA), geared specifically to the residual oil and fat frying, easily could be adopted in São Paulo, would require only a joint effort between departments and the adoption of a geographic information system (GIS), in which were charged the necessary basis to determine the producers points of residual oil and the volume of each establishment. With the crossing of this information would be possible to determine the most critical points of the municipality, where the collection work should be started, starting to serve the entire territory along the project implementation. The adoption of policies like these benefit all citizens, and improve the environmental quality of urban areas, thus avoiding excessive spending on the maintenance of pipes, inconvenience to citizens, worsening public health problems, such as urban pests and creating mechanisms for a sustainable city.
172

Testes rapidos (kits) para avaliação da qualidade de oleos, gorduras e produtos que os contenham e sua correlação com os metodos oficiais da AOCS / Rapids tests (Kits) which serve for quality evaliation of oils, fats and products containin them and this correlatin which AOCS officials methods

Osawa, Cibele Cristina 21 February 2005 (has links)
Orientador: Lireny Ap. G. Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-04T02:22:07Z (GMT). No. of bitstreams: 1 Osawa_CibeleCristina_M.pdf: 1683509 bytes, checksum: 6e2a1d6c8a259eda7c94a6abfcbbe479 (MD5) Previous issue date: 2005 / Resumo: DiaMed Food Analysis Test System (F.A.T.S.) é composto por testes rápidos, alternativos aos métodos convencionais de determinação de ácidos graxos livres (%AGL), índice de peróxidos (IP), concentração de alquenais (teste de p-anisidina) e malonaldeído (teste de TBA). Esses testes podem ser empregados na avaliação de óleos, gorduras e produtos que os contenham. Além disso, os equipamentos são compactos, não necessitando de laboratórios altamente equipados e as quantidades relativamente pequenas de amostra requeridas geram menos resíduos. Eles oferecem, ainda, melhores condições de trabalho aos analistas envolvidos do que os métodos convencionais. Substituem, por exemplo, o reagente de p-anisidina, considerado carcinogênico. Até o momento, apenas os kits de %AGL e IP foram certificados pela AOAC e existem poucos estudos utilizando-os. Em vista disso, o presente trabalho teve como objetivo correlacionar os kits com os métodos oficiais da AOCS, aplicados a óleos vegetais brutos e degomados, óleos refinados, azeites de oliva (avaliados com 4 kits de diferentes faixas de detecção de %AGL e IP), óleos de fritura coletados no restaurante universitário (TBA e p-anisidina) e rações fornecidas por empresa nacional (%AGL, IP, TBA e p-anisidina). Em todos os casos, as análises foram conduzidas em triplicata, utilizando os métodos convencionais. No dia seguinte, analisaram-se as mesmas amostras com os kits correspondentes, de acordo com as instruções do fornecedor. Adotaram-se os métodos Ca 5a-40, Cd 8b-90, Cd 18b-90 e Cd 19b-90, respectivamente, para %AGL, IP, teste de p-anisidina e TBA. As determinações para as amostras de ração foram feitas no lipídio extraído a frio com mistura de éter de petróleo e éter etílico. A correlação entre metodologias foi determinada pelo Método dos Mínimos Quadrados de Regressão Linear (usando o programa Minitab for Windows versão 12.1) e o teste de ANOVA foi utilizado para comparar médias de diferentes metodologias (software SAS for Windows V. 8). Para as amostras de ração e óleo de fritura, a variação entre as amostras testadas usando um mesmo método foi também determinada. Houve alta correlação entre os resultados do método oficial e pelo kit em relação à %AGL e IP de óleos refinados e azeites de oliva e à %AGL das rações e aos valores de p-anisidina de óleos de fritura (r = 0,74-0,99). Os resultados de óleos brutos e degomados foram significativamente diferentes, devido à interferência dos pigmentos presentes. As amostras de ração apresentaram estágio oxidativo pouco avançado, de forma que não puderam ser avaliadas precisamente com os kits. Para os óleos de fritura, o kit de TBA foi mais sensível que o método oficial. Além disso, constataram-se deficiências nos métodos oficiais de determinação de IP, malonaldeído e alquenais, uma vez que o método de peróxido não foi sensível para IP menor que 2 meq/kg, ao passo que o aquecimento empregado no teste de TBA gerou valores mais elevados que os obtidos com o kit equivalente e a presença de água nas amostras e reagentes interferiram nos resultados de p-anisidina. Sendo assim, os kits DiaMed F.A.T.S. forneceram resultados precisos e se tornaram uma opção viável para as superar as limitações econômicas dos estudos de vida útil enfrentadas pelos métodos convencionais, especialmente para amostras com baixo teor lipídico / Abstract: The DiaMed Food Analysis Test System (F.A.T.S.) consists of rapid tests which serve as alternatives for conventional methods in the determination of free fatty acids (%FFA), peroxide value (PV), and the concentration of alkenal (p-anisidine test) and malonaldehyde (TBA test). These tests can be employed in the evaluation of oils, fats and products containing them. Moreover, the compact equipment makes a large, well-equipped laboratory unnecessary and the relatively small sample size generates minimum residues. They also furnish better working conditions for the analysts involved since the p-anisidine used as a reagent is carcinogenic. At present, only the %FFA and PV kits have been certified by the AOCS, but few studies have used them. The present study was thus designed to correlate the results obtained from the use of these kits with those obtained by the official AOCS methods for crude, degummed and refined vegetable oils and olive oils (tested with 4 kits for different levels of %FFA and PV), frying oils collected from the university restaurant (tested for TBA and p-anisidine values) and pet foods supplied by a national industry (tested for %FFA, PV and TBA and p-anisidine values). In all cases the analyses were performed in triplicate using conventional methods. On the following day, the same samples were analyzed using the corresponding kits, according to the instruction of the manufacturer. The official AOCS methods adopted for the determination of %FFA, PV and p-anisidine and TBA values were Ca 5a-40, Cd 8b-90, Cd 18b-90 and Cd 19b-90, respectively. For the pet food samples, lipids were extracted with a mixture of petroleum ether and ethylic ether in cold conditions. The correlations between methodologies were determined using the Least Squares Method of Linear Regression (using Minitab for Windows, version 12.1), and an ANOVA was used to compare the averages of the different methods (SAS for Windows V. 8 software). For both pet food and frying oil samples, the variation between samples tested using the same method was also determined. High correlations were found between the results of official and kit methods in relation to %FFA and PV for refined and olive oils, and in relation to %FFA in pet foods and p-anisidine values in frying oils (r = 0.74-0.99). Results for crude and degummed oils were significantly different, however, due to the effect of pigments. The pet foods exhibited a relatively low oxidative state and thus could not be analyzed accurately with the kits. For frying oils, the TBA kit proved more sensitive than the official method. Moreover, the official methods presented problems for the determination of PV and malonaldehyde and alkenal concentrations, since they were not very sensitive for PV levels of less than 2 meq/kg, whereas the use of heating in the official TBA test led to higher values than those obtained when using the equivalent kit and the presence of water in the samples and reagents interfered in the results of the p-anisidine test. The DiaMed F.A.T.S. kits thus proved to provide accurate results. Moreover, they provide a feasible option for overcoming the economic difficulties of shelf-life studies faced by conventional methods, especially for samples with a low lipid content / Mestrado / Tecnologia de Alimentos / Mestre em Tecnologia de Alimentos
173

Estudo experimental do equilíbrio sólido-líquido dos sistemas tripalmitina + triestearina e óleo de palma + triestearina através da microscopia óptica / Experimental study of solid-liquid equilibrium systems of tripalmitin + tristearin and palm oil + tristearin by optical microscopy

Souza, Jackiney Alfaia 18 August 2018 (has links)
Orientadores: Maria Alvina Krähenbühl, Mariana Conceição da Costa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-18T18:50:59Z (GMT). No. of bitstreams: 1 Souza_JackineyAlfaia_M.pdf: 4286417 bytes, checksum: 4e844ea6eeef919244e2856b211b0a98 (MD5) Previous issue date: 2011 / Resumo: Os triacilgliceróis, oriundos da combinação de um glicerol com ácidos graxos, são os principais componentes dos óleos e gorduras de origem vegetal e animal. Os ácidos graxos e os triacilgliceróis presentes nos óleos e gorduras conferem-lhes propriedades que possibilitam ou não seu uso na formulação de muitos produtos das indústrias químicas, alimentícias e farmacêuticas. Nos últimos anos, o interesse por essas matérias-primas tem crescido e, junto com esse crescimento, a busca por novas tecnologias e pelo aprimoramento dos processos de separação que as envolvem. Para o desenvolvimento e aprimoramento destes processos de separação, é importante estar de posse de informações sobre as propriedades físico-químicas de tais componentes. Desse modo, a construção dos diagramas de fase destes compostos traz avanços na compreensão das transições de fases e podem levar a aplicações mais proveitosas de tais compostos. Para a construção dos diagramas dos triacilgliceróis pesquisados neste trabalho foram usados dados obtidos através da microscopia óptica, que possibilita a aquisição de filmes e imagens durante todo o processo de cristalização ou fusão de uma determinada amostra sendo possível visualizar as fronteiras entre as diferentes regiões de equilíbrio. A descrição do comportamento dos sistemas tripalmitina + triestearina e óleo de palma + triestearina no equilíbrio sólido-líquido é importante para a melhor compreensão do diagrama de fases destes / Abstract: Triacylglycerols, formed by a combination of glycerol with fatty acids, are the main components of vegetable and animal oils and fats. Fatty acids and triacylglycerols present in oil and fatty confers properties that can to allow or not their use in formulation of many chemical, food and in pharmaceutical products. In the last years the interest in these raw materials has grown and with this growth the search for new separation technologies and by the improvement of separation processes of such substances also increases. The development and improvement of separation processes requires the knowledge of physicochemical properties and of the equilibrium conditions of such components. In this way, the construction of phase diagrams of these compounds brings advances in the understanding of phase transitions and can lead to more useful applications of such compounds. The phase diagrams investigated in this study were constructed using data determined by optical microscopy, an experimental technique that allows capture movies and pictures throughout the crystallization or melting process of sample. This technique makes possible delimitate the boundaries between the different equilibrium regions of a system / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
174

Modeling and Experimental Study of Thermal Management for Infrastructure Surface Materials

Zadshir, Mehdi January 2021 (has links)
The rapid growth of population and climate change has subjected our civil infrastructures to high load demands and fast aging or degradation over time. Temperature plays a key role in the performance of the aging infrastructure in form of thermal stress and cracking, temperature-induced material aging and degradation, temperature-dependent deformation, and softening. Thus, the importance of predicting the consequent behavior of the infrastructures under environmental conditions becomes imperative. This research characterizes three infrastructure surface materials, namely asphalt pavement, solar panels, and phase change materials (PCM), models the efficacy of modifiers and novel methods to improve their performance and uses these materials in the design and testing of thermal management systems for different applications. The connection between these materials is the thermal management in pavement overlays, which can be extended to other infrastructure surfaces. Asphalt pavement modified with recycled crumb rubber (CR) is a sustainable way to reuse the millions of tires that used to end in landfills. However, the ultraviolet (UV) rays from the sun have been shown to adversely affect the asphalt’s performance in the long run. The severe photo-oxidation can cause changes in the volatile components of the asphalt and result in hardening, aging, and thermal cracks in it. The effect of UV rays on the rubber-modified asphalt may be even more complex due to the presence of crumb rubber particles and their chemical/physical incompatibility and changes in the glass transition. In order to examine these effects, a PG 64-22 is modified with two percentages of 16.6 wt.% and 20.0 wt.% crumb rubber. Results show the specific heat capacities increase with UV aging with 16.6% having the highest value. The addition of the rubber particles does not change the chemical composition of the binder as confirmed by the elemental analysis. However, after UV exposure, peaks associated with carbonyl and sulfoxide are observed, proving that the rubber-modified binder is subject to photo-oxidation as well. The 16.6. wt.% shows the best performance against aging with the lowest sulfoxide index and the highest aliphatic index. Another advantage of adding crumb rubber particles is the formation of a matrix due to the crosslinking of the rubber particles with the binder after being heated, as approved by microscopic images. The carbon nanotubes (CNT) are used to modify the asphalt binder to improve its rheological characteristics while also enhancing the thermal conductivity of the mixture to facilitate the transfer of heat to the surface. In this study, two samples of 3% and 6% multi walled carbon nanotubes (MWCNTs) are prepared using a foaming technology. Foaming the asphalt via water lowers its viscosity and temperature resulting in the saving of the base material and consumed energy while increasing the coating of the aggregates. The results show the CNTs can improve the thermal conductivity of the foamed binder by almost 2X while not negatively affect its rheology. For the other end of the thermal management system, a new hydronic system is introduced for the building integrated photovoltaics and thermal (BIPVT) silicon module that acts for the dual objectives of collecting heat to be used for the thermal management of the pavement and controlling the surface temperature of the solar module itself for the optimal efficiency under different operating conditions. The BIPVT panel with different flow rates of 100 to 600 ml/min were tested for the effectiveness of the cooling design. The results from experiments and simulations show that at 200 ml/min, an optimal balance for the performance of the panel is achieved to not only reduce the temperature of the panel from 88°C to 65°C, but also generate a partially heated water outlet of 37°C (compared with the 23°C inlet) that can be used for the hot water system of the building, or as the inlet feed to the hydronic cooling/heating pavement system. In addition, the BIPVT design proves to restore the power of the solar module by 24.6% at a 200 ml/min flow rate, as confirmed from the I-V curves. Finally, the feasibility study of converting the waste animal fat to a phase change material (PCM) is explored. In PCMs, the high latent heat characteristics are used to store or release energy during the phase change. The use of PCMs can significantly lower the temperature variation of buildings and the consequent energy use. While most common PCMs are paraffin-based and too expensive for large scale applications, a bio-based and more economic alternative could be the key to its vast use in infrastructure systems. However, more research is needed to achieve an animal fat PCM with high latent heat values. In this study, characterizing the raw fat shows a ~20% saturated content. After hydrolysis, the saturated portion has been increased to 65%, but the improvement in the latent is not significant. However, after separation of the fatty acids by use of crystallization, the resulting fully saturated fatty acids (palmitic and stearic acids) show a 3.5X increase in the value of the latent heat, increasing it from ~55 J/g for free fatty acids to ~195 J/g for saturated fatty acids. The promising results of the high latent heat values make the current bio-based PCM a good alternative that needs to be further explored in the future to be used for applications in buildings and BIPVT panels. Overall, the results of this PhD study provide a comprehensive understanding of materials and systems for thermal management of asphalt pavements and enable the design and development of durable self-heated pavements, which can be immediately extended to other infrastructure applications such as wall panels, net-zero buildings, and solar panels.
175

Lean Startup in a Commercial Management Model Based on Digital Marketing to Increase Sales in Companies of the Health Food Industry

Lazo-Durand, Rafaela, Rojas-Garcia, Jose, Torres-Sifuentes, Carlos, Raymundo, Carlos 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In 2018, the Ministry of Health of Peru reported that more than 50% of the Peruvian population suffers from obesity. In total, 40% of the people affected by this disease are in the metropolitan area of Lima. Moreover, a report by the newspaper Gestión states that, on average, each Peruvian citizen consumes 52 kg of ultra-processed food per year. These alarming figures show that a change in the lifestyle of the citizens of Lima is necessary. It is imperative to increase peoples’ awareness of the importance of leading a healthy lifestyle, which in turn means improving eating habits and exercising. Given the increase of people with health problems caused by poor nutrition, the manufacture of health products, such as nut butter, must be natural, without added sugar, hydrogenated oils, added chemicals, or preservatives. Nuts belong to the group of energy foods and eating them provides great health benefits and helps fight obesity. They are a source rich in proteins and healthy fat, provide energy, and contain vitamins and antioxidants, among other benefits. They are also suitable for vegetarians, vegan, celiac, and diabetic people. Therefore, the manufacture and sale of handmade nut butter is a business opportunity in Lima. To prove this, the lean startup methodology was used, and through the development of viable minimum products, the viability of the project was evidenced. The project management bases of the Project Management Institute (PMI) are used as guidelines to develop the project, and digital marketing tools are applied to make the products known to the target market. / Revisión por pares
176

Effects of a medium chain triglyceride oil mixture and alpha lipoic acid diet on body composition, antioxidant status and plasma lipid levels in the Syrian hamster

Wollin, Stephanie January 2003 (has links)
No description available.
177

Estabilidade oxidativa de óleo de peixe encapsulado e acondicionado em diferentes tipos de embalagem em condição ambiente. / Oxidative stability of encapsulated fish oil stored in different types of packing under ambient conditions.

Pacheco, Selma Guidorizzi Antonio 23 February 2005 (has links)
Tem havido um avanço em pesquisas de produtos marinhos, especialmente devido à presença de ácidos graxos poliinsaturados (AGPI), eicosapentanóico (EPA) e docosahexaenóico (DHA), que são abundantes em óleos de peixe e contribuem para a redução dos índices de triacilglicerol e colesterol no sangue. Contudo, os ácidos graxos poliinsaturados são propensos à oxidação. Quanto maior o grau de insaturação do óleo, menos estável ele é, podendo ocorrer comprometimento das duplas ligações devido à oxidação. Essa pesquisa teve como objetivo estudar a estabilidade de óleo de peixe encapsulado acondicionado em diferentes tipos de embalagens. O óleo utilizado nesse experimento foi cedido pela indústria farmacêutica Cardinal Health Brasil, já refinado e em cápsulas gelatinosas moles. Após a encapsulação, a metade dessas cápsulas foi enviada à Empresa SERPAC Comércio e Indústria Ltda. para o processo de emblistagem, em que foram utilizados os filmes policlorotrifluoroetileno (PCTFE), comercializado sob o nome Aclar Rx 160 (15µ), cloreto de polivinilideno (PVDC-60 gsm2) e policloreto de vinila (PVC-250µ) e, posteriormente, acondicionados em caixas de papel cartonado. O restante foi acondicionado em frascos de polietileno de alta densidade (PEAD) com e sem sachês de sílica e em vidro de cor âmbar. Cada frasco ou embalagem cartonada contendo 60 cápsulas foi armazenado em triplicata sob temperatura ambiente e o óleo analisado a cada 28 dias por um período de 12 meses. As análises realizadas mensalmente no óleo foram a determinação da acidez, do índice de peróxido e da absortividade em 232 e 270nm. A composição em ácidos graxos por cromatografia gasosa, especialmente os teores de EPA e DHA, foi determinada no início, aos 3, 6 e 12 meses. A embalagem em que o óleo apresentou as maiores alterações foi o blister de filme PVC. O melhor desempenho foi encontrado no óleo encapsulado, acondicionado na embalagem de PEAD com dessecante de sílica. Os teores de DHA e EPA mantiveram-se estáveis até o sexto período, ocorrendo uma queda considerável no décimo segundo período no óleo da embalagem do filme PCTFE, devido provavelmente a problemas de a termosoldagem e selagem. / Due to the presence of long chained omega three fatty acids, fish oils have gathered much interest recently. Fish oils are a rich source of polyunsaturated fatty acids (PUFA) like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which reduce blood triacylglycerol and cholesterol levels. However, the higher the unsaturation level, the less stable is the oil which may have its double links compromised due to oxidation.This research main interest was the stability of encapsulated fish oil, stored in different types of packagings. The fish oil used in this experiment was supplied by Cardinal Pharmaceutical Industry in soft gel capsules. After encapsulation, half of the samples were sent to SERPAC Industry LTDA for blistering, where polychlortrifluoroethylene (PCTFE), commercially known as Aclar Rx 160 (15µ), polyvinyldichloride (PVDC-60 gsm2) and polyvinylchoride (PVC-250µ) films were used as three of the treatments. Blisters were packed in carton boxes. The other half of the capsules was packed in amber glass or high density polyethylene (PEAD) rigid flasks with and without silica bags. Each treatment contained 60 capsules in triplicate and all packs were stored under ambient conditions for 12 months. Analytical determinations were performed on the oil every 28 days and included acid and peroxide values, and absortivities in the ultraviolet region at 232 and 270 nm. Fatty acid composition determinations, especifically EPA and DHA content were performed at the beginning of the experiment, after 3, 6 and 12 months. The package, which presented the largest changes in quality of the oil, was the PVC film "blister". The best results were found in encapsulated oil stored in PEAD flasks with silica bags. EPA and DHA contents were kept constant until the sixth period of storage for all samples. The largest changes happened in the oil stored in PCTFE films, with a drastic reduction on the 12 th period due, probably to problems in thermomolding and sealing.
178

The use and interpretation of the nutrition information on the food label of selected fat spreads by female consumers aged 25-45 years, living in Pietermaritzburg.

Wiles, Nicola Laurelle. January 2006 (has links)
Aim: To determine the use and interpretation of the nutrition information on the food label of selected fat spreads by female consumers aged 25 to 45 years, living in Pietermaritzburg. Objectives: This study set out to determine the following objectives regarding the food label: what the demographics of the consumers making use of the label were; how these consumers used the label and their motivation behind this label use and did the use of the label alter the purchase of that product? Method: One hundred and fifty women aged 25-45 years were chosen from an accidental, non-probability sample of consumers shopping at selected supermarkets within Pietermaritzburg. Respondents were presented with a four part questionnaire surrounding the purchase of selected fat spreads. Results: The greatest number of respondents were from the white population group (n = 65), followed by black respondents (n = 46), Indian respondents (n = 29) and then coloured respondents (n = 10). Results showed that the respondent who was most likely to use the nutrition information on the food label had a tertiary education; was a primary food purchaser, lived with other people, had more than R1000 a month to spend on food and was conscious of choosing the healthier option. Fifty five percent of this study sample (n = 82) claimed to use the nutrition information on the label to assist with purchases and 68% (n = 102) found the nutrition information important for purchasing a new product. Of the potential factors that have previously been found to impede the use of the nutrition information label:-inadequate print size, lack of education as well as lack of nutrition information on the food label were found to be factors restricting label use in this study. The most commonly used sources of nutrition information were the media as well as friends and family and the most trusted source was the Health Professional. Discussion: If the nutrition information is to be used both correctly and effectively, there must be a major educational campaign that sets out to meet the needs of the population that are most vulnerable, especially those with an inadequate education. Conclusion: The consumer most likely to use the nutrition information on the food label has a tertiary education, is a primary food purchaser with a large amount of money available for groceries and is conscious of choosing a healthier option. The label is most likely to be used when purchasing a fat spread for the first time. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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Estudo analitico e olfatometrico de oleo de algodão e oleina de palma utilizados em fritura de produtos carneos / Analytical and olfactometry study of deep-fat frying of meat products, using cottonseed and olein oils

Osawa, Cibele Cristina 13 August 2018 (has links)
Orientador: Lireny Aparecida Guaraldo Gonçalves / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-13T18:54:24Z (GMT). No. of bitstreams: 1 Osawa_CibeleCristina_D.pdf: 4048890 bytes, checksum: 700fec6a76f6c4dc29fc9038f5b8e288 (MD5) Previous issue date: 2009 / Resumo: Pretendeu-se através deste estudo levantar dados sobre frituras, em colaboração com agências fiscalizadoras das boas práticas de frituras. Estudou-se o grau de conhecimento de manipuladores de alimentos de 13 estabelecimentos comerciais de Campinas/SP, quanto às boas práticas de frituras, e avaliou-se a qualidade do óleo usado, através de métodos analíticos. Simulou-se, em triplicata, a fritura descontínua de alimentos cárneos empanados em fritadeira com capacidade de 28 L, utilizando dois tipos de óleos vegetais isentos de gorduras trans e disponíveis comercialmente: óleo de algodão e oleína de palma. Adotou-se temperatura de 182ºC e fritura por 4,5 minutos. Por vez, fritaram-se 400-500 g de alimentos. Ao longo do dia, realizaram-se 3 operações de fritura em horários estratégicos e a fritadeira permaneceu ligada a 182ºC por 8h. Não houve reposição com óleo fresco, nem filtragem do óleo. O tempo total de estudo variou de 6 a 17 dias de fritura, sem a troca do óleo e o final dos experimentos foi definido pela avaliação dos óleos usados com testes rápidos. Monitoraram-se os óleos de fritura através de análises físico-químicas: teor de ácidos graxos livres, compostos polares totais e compostos poliméricos, cor Lovibond, dienos conjugados, composição em ácidos graxos, estabilidade oxidativa e testes rápidos para avaliação da qualidade de óleo usado. Embora fossem adotadas as mesmas condições experimentais, mesma fritadeira e mesmo tipo de alimento frito e tipo de óleo, constatou-se que não há reprodutibilidade do processo de fritura. Os alimentos foram avaliados analiticamente e verificou-se perda de umidade, incorporação de óleo nos alimentos, pequenas alterações na composição em ácidos graxos e formação de quantidades desprezíveis de trans, podendo ser rotulados como alimentos zero trans. Estudou-se Texto 265, Viscofrit e Fri-check, testes rápidos de avaliação da qualidade do meio de fritura, utilizando 59 amostras de óleo de fritura. Testo 265 e Viscofrit são alternativas viáveis, se respeitadas suas limitações. Requerem-se estudos mais aprofundados com o Fri-check. Realizou-se, ainda, análise sensorial olfatométrica, na oleína de palma usada na fritura de frango empanado, com 4 julgadores treinados, em quadruplicata, utilizando o método desenvolvido na Universidade Estadual de Oregon (OSME). Os julgadores detectaram e descreveram odores de 135 compostos voláteis presentes no óleo usado de fritura. Trinta e um deles foram identificados por cromatografia em fase gasosa com detector de massas. Dentre eles, compostos não reportados anteriormente na literatura, demonstrando ineditismo do trabalho / Abstract: This study intended to raise data about frying to contribute with supervisor agencies of good practices of frying. The level of knowledge of food manipulators from 13 commercial establishments at Campinas city/SP was studied, in relation to good practices of fryings, and the quality of used oils was evaluated by analytical methods. It was simulated the discontinous frying of meat products with flour coating with a fryer of 28 L-capacity in triplicate, using two types of commercially available zero-trans oils: cottonseed and palm olein oils. The temperature of 182ºC and frying during 4.5 minutes were adopted. Each time, 400-500 g of food samples were fried. During the day, 3 frying operations were strategically performed and the fryer remained on at 182ºC for 8h. There was neither oil replacement, nor filtering. The total time of study varied from 6 to 17 days of frying, without oil exchanging and the end of the experiments was determined by the oil evaluation using fast tests. The frying oils were monitored through physico-chemical analyses: free fatty acids content, total polar compounds and polymeric compounds, Lovibond color, conjugated dienes, composition of fatty acids, oxidative stability and fast tests for evaluation of the quality of used oils. Although the same experimental conditions, the same fryer and the same types of fried food and oil were adopted, it was observed that there was no reproductivity in the frying process. The foods were analytically evaluated and loss of humidity, oil incorporation on foods, small changes in fatty acids composition and minimal amounts of trans-fatty-acid formation were verified, which enables to label them as zero trans food. Testo 265, Viscofrit and Fri-check, fast tests for evaluation of frying fat quality were studied, using 59 samples of frying oil. Testo 265 and Viscofrit are feasible alternatives, if their limitations are respected. Further studies with Fri-check are required. It was still performed olfactometry sensory analysis in the palm olein used in frying chicken breast with flour coating, through the Oregon State University method (OSME), with 4 trained judges, in quadruplicate. Judges detected and described odors of 135 volatile compounds present in the used frying oil. Thirty-one of them were identified by gaschromatography equipped with mass detector. Among them, it was found compounds not previously reported in the literature / Doutorado / Mestre em Tecnologia de Alimentos
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Estudo do efeito da adição de gorduras alternativas na cristalização da manteiga de cacau / Influence of the addition of alternative fats on cocoa butter crystallization

Quast, Leda Battestin 15 April 2008 (has links)
Orientadores: Theo Guenter Kieckbusch, Valdecir Luccas / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-10T18:45:44Z (GMT). No. of bitstreams: 1 Quast_LedaBattestin_D.pdf: 1972832 bytes, checksum: a34ffd60e85d88858ba49961e507cd34 (MD5) Previous issue date: 2008 / Resumo: A influência da incorporação de gorduras alternativas low e zero trans na cristalização da manteiga de cacau foi avaliada através da caracterização física de misturas binárias de manteiga de cacau com gordura de cupuaçu, gordura CBR low trans e gordura CBS, nas proporções de 5, 10, 15, 20, 25 e 30 %. O processo de pré-cristalização (temperagem) foi realizado em um reator encamisado de escala piloto dotado de um agitador e com capacidade para 700 mL. As amostras foram caracterizadas através da curva de sólidos, tensão de ruptura (snap test), calorimetria diferencial de varredura e difração de raios-X. A melhor condição de pré-cristalização da manteiga de cacau pura (taxa de resfriamento de 1,8 ºC/min, cristalização à 24 ºC por um tempo de 8 minutos) também foi utilizada nos ensaios com as misturas, com exceção das amostras com 20, 25 e 30 % de CBR e CBS que foram pré-cristalizadas a 23 ºC por 10 minutos. A manteiga de cacau apresentou um perfil de fusão de gordura na boca, DS(25ºC-35ºC), de 59,2 %, que sofreu apenas pequenas alterações com a adição de até 20 % de cupuaçu e até 30 % de CBR. A curva do conteúdo de sólidos sugere a formação de um eutético entre a manteiga de cacau e a gordura CBS. A tensão de ruptura para a manteiga de cacau foi de 2,48 kgf/cm2 e a adição das gorduras tende a diminuí-la, sendo que com 30 % de cupuaçu e 30 % de CBR esse valor foi 1,90 kgf/cm2 e 1,81 kgf/cm2, respectivamente. Para a amostra com 30 % de CBS a tensão de ruptura baixou para 0,39 kgf/cm2. Observou-se uma diminuição do ponto de fusão das misturas quando comparadas à da manteiga de cacau pura. A difração de raios-X identificou a forma cristalina b como predominante para a manteiga de cacau e para a gordura de cupuaçu enquanto que para as gorduras CBR e CBS a principal forma cristalina é a b'. A incorporação de apenas 10 % das gorduras CBR e CBS à manteiga de cacau promoveu interferências na estruturação cristalina das amostras. O estudo indicou ser possível adicionar até 30 % de gordura de cupuaçu ou CBR e até 10 % de gordura CBS sem alterar de forma sensível os atributos físicos da manteiga de cacau / Abstract: Physical properties of pre-crystallized cocoa butter with the addition of alternative low and zero trans fats were studied. Binary mixtures of cocoa butter were conducted using cupuassu fat, CBR low trans and CBS at 5, 10, 15, 20, 25 and 30 % (w/w) levels. Pre-crystallization was carried out using a lab scale jacket vessel (700 mL) whit stirring system. Samples were evaluated by means of solid fat content, snap test, differential scanning calorimetry and X-Ray diffraction. The better condition for plain cocoa butter pre-crystallization was determined as follows: cooling rate (1,8 ºC/min), crystallization time (8 minutes), crystallization temperature (24 ºC). These conditions were also used for mixtures precrystallization (tempering). Mixtures with 20, 25 and 30 % of CBR and CBS were pre-crystallized at 23 ºC for 10 minutes. Regarding to solid fat content, cocoa butter fusion profile DS(25ºC-35ºC) was 59,2 %. Similar values were obtained for mixtures with up to 30 % of cupuassu and up to 30 % of CBR fats. Mixtures with CBS fat indicated eutectic effect. Snap value for crystallized cocoa butter was 2,48 kgf/cm2. The snap values decreased with the increase of the alternative fats proportion. Mixtures containing cupuassu fat or CBR have similar trend regarding to snap values profile. For mixtures with 30 % of cupuassu and CBR the snap values were 1,90 kgf/cm2 and 1,81 kgf/cm2, respectively. CBS 30% have the lowest snap value (0,39 kgf/cm2). Similar trend was observed regarding to melting point. Alternative fats incorporation decreased the melting point of the mixtures. Regarding to X-Ray diffraction, cocoa butter and cupuassu fat patterns results showed the formation of ß phase. For CBS and CBR patterns, there are evidence of ß¿ phase formation. The addition of 10 % CBR and CBS fat to cocoa butter was detected by X-ray diffraction patterns. The addition of up to 30 % cupuassu or CBR fat, and up to 10 % CBS butter showed no significant differences of physical properties when compared to cocoa butter / Doutorado / Engenharia de Processos / Doutor em Engenharia Química

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