On the physical refining of edible oils for obtaining high quality products

Vegetable oils are important compounds of the human diet and they should be refined before consumption. Consumers demand for healthier products as well as stiff environmental legislation are forcing refining industries towards changes and improvement of processes. In this context, this thesis has as main objective to investigate/improve the physical refining of vegetable oils, emphasizing the bleaching step. As first step, a HPLC methodology for simultaneous quantification of carotenes and tocols was developed and validated, and lately, it was used by our research groups. Then, bleaching step of palm oil, nowadays the most consumed oil in the world, was studied under different aspects: (1) determining kinetics, equilibrium and thermodynamic parameters of adsorptive removal of carotenes and phosphorus onto acid activated bleaching earth; (2) influence of different procedures on final color of palm oil; (3) influence of bleaching earth kind on final color of palm oil. These studies were important for a better understanding of bleaching process of palm oil, and some conclusions were obtained: adsorptive removal of carotenes and phosphorus onto acid activated bleaching earth occurs by chemisorption and it is endothermic; new procedures in the bleaching step can improve final color of palm oil when using the same amount of bleaching earth and deodorization time; a hypothesis was proposed to explain how the kind of bleaching earth can interfere in the final color of palm oil. Further studies are still necessary to optimize bleaching step and the new procedures suggested. Later, physical deacidification was studied by computer simulation and experimental data from literature. It was compared two mathematical approaches: differential and flash distillations. This last one presented better results regarding acidity and neutral oil loss profiles. In this approach, it was considered the heat transfer equations. In this way, this thesis presents an advance in refining process towards high quality products and the use of less chemicals

Investigação sobre o refino físico de óleos vegetais para obtenção de produtos de alta qualidade

Orientadores: Antonio José de Almeida Meirelles, Roberta CerianiTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosAbstract: Vegetable oils are important compounds of the human diet and they should be refined before consumption. Consumers demand for healthier products as well as stiff environmental legislation are forcing refining industries towards changes and improvement of processes. In this context, this thesis has as main objective to investigate/improve the physical refining of vegetable oils, emphasizing the bleaching step. As first step, a HPLC methodology for simultaneous quantification of carotenes and tocols was developed and validated, and lately, it was used by our research groups. Then, bleaching step of palm oil, nowadays the most consumed oil in the world, was studied under different aspects: (1) determining kinetics, equilibrium and thermodynamic parameters of adsorptive removal of carotenes and phosphorus onto acid activated bleaching earth; (2) influence of different procedures on final color of palm oil; (3) influence of bleaching earth kind on final color of palm oil. These studies were important for a better understanding of bleaching process of palm oil, and some conclusions were obtained: adsorptive removal of carotenes and phosphorus onto acid activated bleaching earth occurs by chemisorption and it is endothermic; new procedures in the bleaching step can improve final color of palm oil when using the same amount of bleaching earth and deodorization time; a hypothesis was proposed to explain how the kind of bleaching earth can interfere in the final color of palm oil. Further studies are still necessary to optimize bleaching step and the new procedures suggested. Later, physical deacidification was studied by computer simulation and experimental data from literature. It was compared two mathematical approaches: differential and flash distillations. This last one presented better results regarding acidity and neutral oil loss profiles. In this approach, it was considered the heat transfer equations. In this way, this thesis presents an advance in refining process towards high quality products and less consumption of inputsResumo: Os óleos vegetais são importantes componentes da dieta humana e devem ser refinados antes do consumo. A demanda dos consumidores por produtos mais saudáveis, assim como regulamentações ambientais cada vez mais rígidas têm forçado os processadores de óleos vegetais a buscarem mudanças e aperfeiçoamento dos processos. Neste contexto, este trabalho de tese tem como objetivo investigar e aperfeiçoar o refino físico de óleos vegetais, com ênfase na etapa de branqueamento. Numa primeira etapa, uma metodologia para quantificar simultaneamente carotenos e tocoferóis foi desenvolvida e validada, e posteriormente, utilizada pelo grupo de pesquisa. Então, a etapa de branqueamento de óleo de palma, atualmente o óleo mais consumido mundialmente, foi estudada sob diferentes aspectos: (1) determinação da cinética, equilíbrio e parâmetros termodinâmicos do processo de adsorção de carotenos e fósforo em terra clarificante acidamente ativada; (2) influência de diferentes procedimentos na cor do óleo de palma refinado; (3) influência do tipo de terra clarificante na cor do óleo de palma refinado. Estes estudos foram importantes para um melhor entendimento do processo de branqueamento de óleo de palma, e algumas conclusões foram obtidas: a adsorção de carotenos e fósforos pela terra clarificante acidamente ativada ocorre por via química, e é um processo endotérmico; a utilização de novos procedimentos na etapa de branqueamento do óleo de palma pode melhorar a coloração obtida ao final do processo; o refino em duas etapas utilizando duas desodorizações em condições moderadas de temperatura apresentou melhor coloração final quando comparado ao processo utilizando a mesma quantidade de terra clarificante e tempo de desodorização; uma hipótese foi sugerida para explicar como o tipo de terra clarificante (neutra ou acidamente ativada) pode interferir na coloração final do óleo de palma. Ainda são necessários mais estudos para otimizar a etapa de branqueamento e os novos procedimentos sugeridos. Por último, a etapa de desacidificação por via física foi estudada através de simulação computacional e dados experimentais disponíveis na literatura. Foram comparadas duas abordagens matemáticas: a diferencial e a flash. Esta última apresentou resultados mais realísticos quanto aos perfis de acidez e perda de óleo neutro. Foi ainda considerada na abordagem flash equações de transferência de calor. Dessa forma, pode-se concluir que este trabalho de tese apresentou avanços nos processos de refino físico de óleos vegetais para obtenção de produtos de maior qualidade final e menor consumo de insumosDoutoradoEngenharia de AlimentosDoutora em Engenharia de Alimento

Thermal and physical properties of crude palm oil with higher oleic content

Interspecific hybridization of oil palms (E. guineensis × E. oleifera) was initially exploited to provide disease resistance and, consequently, increased oleic acid content. Besides the growing importance of this cultivar to the market, there is little information about this oil’s properties. In this context, this study aimed to determine a comprehensive physicochemical and thermal characterization of hybrid palm oil (HOPO) compared with the better-known African palm oil (APO). Differences in the distribution of fatty acids, carotenoids, and tocols were observed. Minor differences in density and viscosity were found between the oils, with no relevance for the materials’ processing design. Nevertheless, HOPO showed unique crystallization behavior, which potentially can affect industrial operations, such as fractionation. HOPO did not present the two thermal characteristic regions of APO, attributed to olein and stearin fractions. The HOPO demonstrated a decrease in the melting point of more than 3 °C in relation to APO, and a reduction in the crystallization point of more than 6 °C. Furthermore, besides the higher content of unsaturated fatty acids, HOPO was more stable than APO due to a higher antioxidant content. These results could be useful to establish operation conditions for processes using palm oil from hybrid oil palm

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio