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O aquecimento por micro-ondas (MO) é uma tecnologia emergente para o processamento térmico contínuo de alimentos líquidos. A taxa d aquecimento e a profundidade de penetração das MO dependem das propriedades dielétricas (PD) do alimento (permissividade elétrica relativa e fator de perda dielétrica ). As PD de água de coco verde e de sucos de frutas cítricas (laranja, limão e tangerina) foram estudadas empregando a técnica de cabo coaxial. As medições foram realizadas em 101 frequências na faixa de 500 MHz até 3000 MHz e em temperaturas entre 0 °C e 90 °C, o que permitiu estudar o efeito da frequência e da temperatura. A profundidade de penetração foi calculada com uma expressão derivada das equações de Maxwell para eletromagnetismo. O trabalho experimental começou com as PD de: água de coco verde simulada, água destilada, solução de açúcares e sais da água de coco verde e água de coco verde natural. Resultados foram comparados para avaliar a contribuição de cada componente (água, açúcares e sais). PD de sucos de diferentes variedades de laranjas, tangerinas e limões, assim como misturas de sucos de duas variedades de laranja, foram também avaliadas. A condutividade elétrica das amostras foi medida nas diferentes temperaturas e o seu efeito sobre o fator de perda foi analisado. Os resultados foram comparados nas frequências comerciais de 915 MHz e 2450 MHz. O comportamento dielétrico das amostras estudadas foi caracterizado por dois mecanismos principais: a condução iônica de sais dissolvidos e a rotação dipolar da molécula de água, os quais têm predominância variável dependendo da frequência e da temperatura. A permissividade elétrica relativa de todas as amostras decresceu com o incremento da temperatura e da frequência, enquanto que o comportamento do fator de perda com a temperatura e frequência foi determinado pela composição. Os sais apresentaram maior efeito que os açúcares sobre as PD da água de coco verde. A profundidade de penetração foi maior na frequência de 915 MHz, associada com o aumento no comprimento de onda. Correlações polinomiais foram ajustadas nas frequências comerciais para representar a dependência com a temperatura. / Microwave (MW) heating is an emergent technology for thermal processing of liquid food products. Heating rate and MW penetration depth depending on dielectric properties (DP) of food material (relative electrical permittivity () and dielectric loss factor ()). DP for green coconut water (GCW) and citrus fruits juices (orange, tangerine and lemon) were studied by open-ended coaxial line probe technique. The measurements were carried out for frequencies between 500 MHz and 3000 MHz at 101 points in this range and temperatures from 0 °C to 90 °C, which allowed studying temperature and frequency effect. The power penetration depth was calculated using an expression derived from the Maxwell equations for electromagnetism. Experimental work started with DP measurement for: simulated (GCW), distilled water, sugars and salts solutions of (GCW) and natural (GCW). Results were compared in order to evaluate the each component contribution (water, sugars and salts). DP for juices from different orange, tangerine and lemon varieties as well as mixtures of orange juice from two varieties, were also evaluated. Electrical conductivity was measured and its effect on dielectric loss factor was analyzed. Obtained results were compared at commercial frequencies of 915 MHz and 2450 MHz. Dielectric behavior of studied samples was characterized by two main mechanisms: ionic conduction of dissolved salts and dipole rotation of water molecules, which presented variable predominance, depending on frequency and temperature. Relative electrical permittivity decreased with increase on both temperature and frequency for all tested samples, whereas dielectric loss factor behavior with temperature and frequency was determined by composition. Salts showed higher effect than sugars on dielectric properties of GCW. Penetration depth was higher at 915 MHz, associated to increasing wave length. Polynomial correlations for DP were adjusted at commercial frequencies in order to illustrate the temperature dependence.

No presente projeto, foi estudada a viabilidade do uso da lata de alumínio como embalagem para suco de laranja natural submetido a tratamento térmico mínimo, através de ensaios de vida de prateleira durante um período de 57 dias, com armazenamento em geladeira. O suco foi processado em trocador de calor tipo placas às temperaturas nominais de pasteurização de 80ºC e 85ºC e embalado à temperatura ambiente sob atmosfera de nitrogênio em latas de alumínio revestidas com verniz protetor. As análises foram efetuadas na freqüência de 14 dias (1º, 15º, 29º, 43º e 57º dia após o processamento). As respostas analisadas foram pH, ºBrix, acidez titulável, “ratio"(ºBrix/acidez titulável), sólidos totais, sólidos insolúveis e detecção de íons alumínio e análises microbiológicas (contagem total de bactérias mesofílicas e contagem de leveduras e bolores). As análises de variância dos resultados indicaram que as condições de processo reais estudadas (82,5ºC - 35 s; 82,5ºC - 45 s; 87,5ºC - 35 s e 87,5ºC - 45 s) não influenciaram as características físico-químicas do suco (pH, ºBrix, acidez titulável, “ratio"). Durante o período de armazenamento testado (57 dias), foi verificado que não houve aumento do conteúdo de íons alumínio no suco de laranja e os valores encontrados foram abaixo do limite tolerado de ingestão semanal de alumínio (Provisional Tolerable Weekly Intake – PTWI) estabelecido pela FAO/WHO. Sob o aspecto microbiológico (contagem total de bactérias mesofílicas e contagem de leveduras e bolores), foi verificada a eficiência do processo de pasteurização. Para as condições de processo 82,5ºC – 45 s e 87,5ºC – 45 s, o número de bactérias mesofílicas sobreviventes diminuiu com o tempo de armazenamento. Para as condições 82,5ºC – 35 s e 87,5ºC – 35 s, houve aumento do número de sobreviventes a partir do 23º dia e 33ºdia, respectivamente, em relação ao suco não-processado. As condições de processo empregadas indicaram, no período de armazenamento testado (57 dias), valores de contagem de leveduras e bolores inferiores ao limite máximo tolerado pela Legislação Brasileira para suco “in natura" (104 UFC/mL). / In this research project, minimal heat treatment was studied for fresh single- strength orange juice. The juice was packaged in aluminum cans and stored at refrigerated temperature during 57 days concerning shelf life tests. The juice was processed using a plate heat exchanger at nominal pasteurization temperatures 80ºC and 85ºC and packaged in aluminum varnished cans at ambient temperature, under nitrogen atmosphere. The analyses, conducted each 14 days (1st, 15th, 29th, 43rd and 57th day after the processing day), were: pH, ºBrix, titratable acidity as citric acid, ratio (ºBrix/ titratable acidity), total solids, water-insoluble solids, aluminum ions content and microbiological analyses (total plate count and yeast and mold count). Statistical analyses indicated that the physic-chemical characteristics of orange juice were not influenced by the real process conditions (82.5ºC - 35 s; 82.5ºC - 45 s; 87.5ºC - 35 s and 87.5ºC - 45 s). The orange juice aluminum ions content did not increase during the 57 days storage and all the values were lower than the Provisional Tolerable Weekly Intake (PTWI) established by FAO/WHO. In addition, the pasteurization process showed effective in reducing microbial load. For the temperature-time conditions 82.5ºC - 45 s and 87.5ºC - 45 s, the number of surviving organisms decreased as the storage period increased. However for the temperature-time conditions 82.5ºC - 35 s and 87.5ºC - 35 s, there was an increase of the number of surviving organisms after 23rd day and 33rd day, respectively, compared to raw orange juice. During the 57 days storage, the yeast and mold count were lower than the maximum acceptable limit established by Brazilian Legislation (104 CFU/mL).

In this study, glucose oxidase and polyphenol oxidase were immobilized in conducting copolymer poly(N-(4-(3-thienyl methylene)-oxycarbonylphenyl)maleimide)-co-pyrrole(P(MBThi-co-Py)). A copolymer was electrochemically synthesized by using sodium dodecyl sulfate (SDS) as supporting electrolyte and characterized by FTIR, scanning electron microscopy (SEM) and conductivity measurements. Immobilization of glucose oxidase (GOD) and polyphenol oxidase (PPO) enzymes were performed in conducting PPy and P(MBThi-co-Py) matrices by electropolymerization. Kinetic parameters, maximum reaction rate (Vmax) and Michaelis-Menten constant (Km) were determined for the enzyme electrodes by help of Lineweaver-Burk plot. Effect of temperature and pH on GOD and PPO activity was examined. Operational stability and long term stability of the enzyme electrodes were investigated. The immobilized GOD and PPO electrodes were used for determination of glucose amount in Turkish orange juices and analyzing the concentration of phenolic compounds in Turkish red wines respectively.

The aim of current research is to analyze the effect of microfluidization on the stability and some quality characteristics of orange juice with respect to treatment pressure and cycle. Orange juice was microfluidized with four different pressures (34, 69, 103 and 138 MPa) and three different cycles (1, 2 and 3) at 18 &plusmn / 2 0C. Physical and chemical properties of microfluidized juices were compared with non-microfluidized freshly squeezed orange juice. Microfluidization made orange juice brighter and decreased redness and yellowness. There was a huge difference between non-microfluidized juice and microfluidized juice in terms of particle size. Microfluidization decreased the volume weighted mean (VWM) of orange juice between 90 % and 97 %. The results of total phenol content and antioxidant activity experiments showed that treatment pressure affected them positively / however cycle had not a significant effect on total phenol content and antioxidant property of orange juice (p&lt / 0.05). Our current research also includes effect of microfluidization on stability of orange juice. The broken down of aggregated structure and reduction in particle size due to treatment were observed by the scanning electron and light microscopes. Therefore, it was observed that treated orange juice could be homogeneous and opaque for 14 days at 4 0C. Cloud stability of juice showed that both pressure and cycle had important effect on the cloud stability (p&lt / 0.05). Microfluidization made the juice very stable but increase in pressure and cycle resulted in less stable juice. It was also measured that pectin methyl esterase activity was increased due to treatment of microfluidization.

The quality and shelf-life of pressure processed (150, 200 and 250 MPa at 25 and 35&deg / C for 5, 10 and 15 minutes) orange, tomato and carrot juices were compared to fresh and thermally pasteurised (60&deg / C for 5, 10 and 15 minutes and 80&deg / C for 1 minute) juices. Treatments were capable of microbial inhibition of juices to non-detectable levels. The change in ascorbic acid content of HHP treated juices was not statistically significant (p&gt / 0.05). Both heat treatments at 60 and 80&deg / C, displayed a significant loss and induced a decrease in the free radical scavenging activity but was not affected by HHP treatments. Pressurization at 250 MPa at 35&deg / C for 15 minutes and thermal pasteurization at 80&deg / C for 1 minute and stored at 4 and 25&deg / C for shelf-life analysis. HHP treated juices showed a small loss of antioxidants (below 10%) at both storage temperatures whereas the loss is higher (about 30%) in the heat treated juices through shelf life (30 days). The pressurized juices, stored at 25&deg / C, contained ascorbic acid better than heat treated ones after 30 days. The total color changes were minor (&amp / #8710 / E=10) for all pressurized juices but for heat pasteurized samples, higher as a result of insufficient antioxidant activity. The pH of juices was not affected by treatment, storage temperature or time. HHP yielded a better product, regarding the studied parameters of the juices compared to the conventional pasteurization. Therefore, HHP treatment (250 MPa, 35&deg / C for 15 minutes) can be recommended for industrial production of fresh fruit and vegetables.

Made available in DSpace on 2014-06-11T19:23:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-16Bitstream added on 2014-06-13T20:30:22Z : No. of bitstreams: 1 dourado_gkzs_me_arafcf.pdf: 2109934 bytes, checksum: 79ddf2b14ea1fc3f4779c4b22b8e7f81 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Tem sido mostrado que a hesperidina, um flavonóide encontrado nas frutas cítricas e especialmente no suco de laranja, apresenta atividade antiinflamatória e imunomodulatória, entre outras. O presente estudo avaliou os efeitos da ingestão do suco de laranja (SL) como fonte natural da hesperidina, da glicosil hesperidina isolada (GH) e da mistura de ambos (SL-GH), sobre o sistema imune inato de camundongos. Para tanto, foram medidos os parâmetros de produção e inibição da produção de óxido nítrico (NO), e de liberação das citocinas IL-10, IL-12 e TNF- em culturas de macrófagos peritoneais ex vivo. Os macrófagos foram obtidos de grupos de animais previamente tratados com GH, SL, SL-GH ou solução salina (SS). Em seguida as células foram tratadas com GH e lipopolissacarídeo bacteriano (LPS) in vitro. Os resultados mostraram que o tratamento com suco de laranja estimulou a produção de NO de forma moderada (60μmol de NO- 2) pelos macrófagos, aumentou a liberação da citocina IL-10 e diminuiu significativamente a produção de TNF- . O tratamento com G-hesperidina inibiu completamente a produção de NO em macrófagos mesmo na presença de LPS, aumentou a produção da citocina IL-12 e diminuiu a produção de IL-10. Estes resultados sugerem que a ingestão de suco de laranja é benéfica ao sistema imune, podendo apresentar ação contra possíveis agentes infecciosos. A flavanona Ghesperidina isolada pode ser considerada um composto anti-inflamatório nos casos onde ocorre a intensa liberação de óxido nítrico, tais como as doenças inflamatórias / It has been shown that hesperidin, a flavonoid found in citrus fruits and especially in the orange juice, has anti-inflammatory and immunomodulatory, among others. This study evaluated the effects of ingestion of orange juice (SL) as a natural source of hesperidin, isolated glucosyl hesperidin (GH) and a mixture of both (SL-GH) on the innate immune system of mice. To this end, it was measured the parameters of production and inhibiting the production of nitric oxide (NO), and release of cytokines IL-10, IL-12 and TNF-α in cultures of peritoneal macrophages ex vivo. Macrophages were obtained from groups of animals previously treated with GH, SL, SL-GH or saline solution. Then the cells were treated with GH and bacterial lipopolysaccharide (LPS) in vitro. The results showed that treatment with orange juice stimulated the production of NO in a moderate (60µmol NO- 2) by macrophages, increased the release of cytokine IL-10 and significantly decreased the production of TNF-α. Treatment with G-hesperidin completely inhibited NO production in macrophages, even in the presence of LPS, increased the production of cytokine IL-12 and decreased production of IL-10. These results suggest that ingestion of orange juice is beneficial to the immune system, may bring suit against possible infectious agents. The isolated G-flavanone hesperidin can be considered an anti- inflammatory compound in cases where it occurs intense release of nitric oxide, such as inflammatory diseases

Submitted by Bruna Camargo de Oliveira null (ocamargob@yahoo.com.br) on 2017-10-23T17:39:42Z No. of bitstreams: 1 Dissertacao mestrado_Defesa.pdf: 1369561 bytes, checksum: 733399cb5d97f6acb89f7d6c817e9d1d (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-10-26T16:24:16Z (GMT) No. of bitstreams: 1 oliveira_bc_me_bot.pdf: 1369561 bytes, checksum: 733399cb5d97f6acb89f7d6c817e9d1d (MD5) / Made available in DSpace on 2017-10-26T16:24:16Z (GMT). No. of bitstreams: 1 oliveira_bc_me_bot.pdf: 1369561 bytes, checksum: 733399cb5d97f6acb89f7d6c817e9d1d (MD5) Previous issue date: 2017-08-23 / Introdução: Após infarto do miocárdio (IM) ocorrem modificações complexas na estrutura do miocárdio. Essas alterações determinam a remodelação cardíaca (RC) e a disfunção ventricular. Alguns mecanismos como estresse oxidativo e inflamação modulam esse processo. O suco de laranja (SL) possui fitonutrientes na forma de polifenóis, como os flavonóides que têm ação anti-inflamatória e anti-estresse oxidativo. Levantamos a hipótese de que o consumo de SL atenua o processo de RC após IM, por ação no estresse oxidativo e na inflamação cardíaca. Objetivo: Avaliar a influência do consumo de SL na RC após IM por meio de variáveis morfológicas, funcionais, estresse oxidativo, inflamação e metabolismo energético. Materiais e métodos: Como delineamento do estudo foram 142 ratos machos pesando em torno de 200-250g, que sofreram um procedimento cirúrgico. Os animais foram alocados em 2 grupos, sham e infartados. Foi realizado ecocardiograma (ECO) inicial. Posteriormente, cada um desses grupos foi alocado em outros 2 grupos. O grupo sham controle (S0) recebeu água com maltodextrina, e o grupo sham tratado (SSL) recebeu SL; o grupo infarto controle (I0) recebeu água com maltodextrina e o grupo infarto tratado (ISL) recebeu SL. A análise estatística foi feita pela ANOVA de duas vias complementado por Holm-Sidak e os resultados apresentados em média ± desvio padrão, o nível de significância adotado foi de 0,05. Resultados: O estudo morfológico realizado pelo ECO mostrou que o infarto resultou em aumento do DDVE, DSVE e AE, corrigidas pelo peso corporal e aorta, além de EDPP do VE, IMVE, e do peso do VE e VD corrigidas pelo peso corporal. Além disso, o infarto levou a maior valor de índice de Tei e AE, menores valores das variáveis: % encurtamento endocárdico, VEPP, FE, FVA, S lateral, S septal e S média. Em relação ao estresse oxidativo o infarto levou a maior atividade de SOD e HL, e menor expressão da HO-1. No que se refere ao metabolismo energético no coração dos animais infartados observamos maior valor na atividade da enzima LDH e menor valor na atividade da enzima β-OH acil CoA DH, CS e nos Complexos Respiratórios I e II e ATP sintase. Em relação à inflamação o grupo I0 apresentou concentrações maiores de INF- e IL-10 do que o grupo sham. O consumo de SL nos animais infartados resultou em diminuição do DDVE, DSVE e AE, maiores valores da S septal e menor atividade da GSH-Px. O consumo de SL entre os grupos infartados mostraram maiores valores de fosfofrutoquinase, menores valores de IL-10 e do IFN- Os animais que consumiram SL apresentaram maiores valores de HO-1. Conclusão: O suco de laranja atenuou a remodelação cardíaca em ratos infartados possivelmente via aumento da heme oxigenase -1. / Introduction: After myocardial infarction (MI) complex changes occur in myocardial structure. These changes determine cardiac remodeling (CR) and ventricular dysfunction. Some mechanisms such as oxidative stress and inflammation modulate this process. Orange juice (OJ) has phytonutrients in the form of polyphenols, such as flavonoids that have anti-inflammatory and anti-oxidative stress. We hypothesized that the consumption of OJ attenuates the CR process after MI, by action on oxidative stress and cardiac inflammation. Objective: To evaluate the influence of OJ consumption on CR after MI through variables functional, morphological, oxidative stress, inflammation and energy metabolism. Materials and methods: As a study design were 142 male rats weighing around 200-250 g, who underwent a surgical procedure. The animals were allocated in 2 groups, sham and infarcts. An initial echocardiogram (ECHO) was performed. Subsequently, each of these groups was allocated in 2 other groups. Sham control group (S0) received water with maltodextrin, and treated sham group (SSL) received OJ; control infarction group (I0) received water with maltodextrin and treated infarction group (ISL) received OJ. Statistical analysis was performed by the two-way ANOVA supplemented by Holm-Sidak and the results presented in mean ± standard deviation, the level of significance adopted was 0.05. Results: The morphological study performed by ECHO showed that the infarction resulted in an increase in LVDD, LVSD and AE, corrected for body weight and aorta, as well as LVMT, LVMI, and LV and RV weight corrected for body weight. In addition, infarction led to higher values Tei index and AE, lower values of endocardial fractional shortening, PESV, EF, AVF, S side, S septal and S mean. In relation to oxidative stress the infarction led to higher SOD and HL activity, and lower expression of HO-1. Regarding the energetic metabolism in the heart of the infarcted animals we observed a higher value in LDH enzyme activity and a lower value in the activity of the enzyme β-OH acil CoA DH, CS and in the Respiratory Complexes I and II and ATP synthase. Regarding inflammation, group I0 presented higher concentrations of INF-γ and IL-10 than the sham group. The consumption of OJ in infarcted animals resulted in decreased LVDD, LVSD and AE, higher values S septal and lower activity of glutathione peroxidase. The consumption of OJ among the infarcted groups showed higher values of phosphofructokinase, lower values of IL-10 and of IFN-γ. The animals that consumed OJ had higher values of HO-1. Conclusion: Orange juice attenuated cardiac remodeling in infarcted rats possibly via increased heme oxygenase-1.

No presente projeto, foi estudada a viabilidade do uso da lata de alumínio como embalagem para suco de laranja natural submetido a tratamento térmico mínimo, através de ensaios de vida de prateleira durante um período de 57 dias, com armazenamento em geladeira. O suco foi processado em trocador de calor tipo placas às temperaturas nominais de pasteurização de 80ºC e 85ºC e embalado à temperatura ambiente sob atmosfera de nitrogênio em latas de alumínio revestidas com verniz protetor. As análises foram efetuadas na freqüência de 14 dias (1º, 15º, 29º, 43º e 57º dia após o processamento). As respostas analisadas foram pH, ºBrix, acidez titulável, “ratio”(ºBrix/acidez titulável), sólidos totais, sólidos insolúveis e detecção de íons alumínio e análises microbiológicas (contagem total de bactérias mesofílicas e contagem de leveduras e bolores). As análises de variância dos resultados indicaram que as condições de processo reais estudadas (82,5ºC - 35 s; 82,5ºC - 45 s; 87,5ºC - 35 s e 87,5ºC - 45 s) não influenciaram as características físico-químicas do suco (pH, ºBrix, acidez titulável, “ratio”). Durante o período de armazenamento testado (57 dias), foi verificado que não houve aumento do conteúdo de íons alumínio no suco de laranja e os valores encontrados foram abaixo do limite tolerado de ingestão semanal de alumínio (Provisional Tolerable Weekly Intake – PTWI) estabelecido pela FAO/WHO. Sob o aspecto microbiológico (contagem total de bactérias mesofílicas e contagem de leveduras e bolores), foi verificada a eficiência do processo de pasteurização. Para as condições de processo 82,5ºC – 45 s e 87,5ºC – 45 s, o número de bactérias mesofílicas sobreviventes diminuiu com o tempo de armazenamento. Para as condições 82,5ºC – 35 s e 87,5ºC – 35 s, houve aumento do número de sobreviventes a partir do 23º dia e 33ºdia, respectivamente, em relação ao suco não-processado. As condições de processo empregadas indicaram, no período de armazenamento testado (57 dias), valores de contagem de leveduras e bolores inferiores ao limite máximo tolerado pela Legislação Brasileira para suco “in natura” (104 UFC/mL). / In this research project, minimal heat treatment was studied for fresh single- strength orange juice. The juice was packaged in aluminum cans and stored at refrigerated temperature during 57 days concerning shelf life tests. The juice was processed using a plate heat exchanger at nominal pasteurization temperatures 80ºC and 85ºC and packaged in aluminum varnished cans at ambient temperature, under nitrogen atmosphere. The analyses, conducted each 14 days (1st, 15th, 29th, 43rd and 57th day after the processing day), were: pH, ºBrix, titratable acidity as citric acid, ratio (ºBrix/ titratable acidity), total solids, water-insoluble solids, aluminum ions content and microbiological analyses (total plate count and yeast and mold count). Statistical analyses indicated that the physic-chemical characteristics of orange juice were not influenced by the real process conditions (82.5ºC - 35 s; 82.5ºC - 45 s; 87.5ºC - 35 s and 87.5ºC - 45 s). The orange juice aluminum ions content did not increase during the 57 days storage and all the values were lower than the Provisional Tolerable Weekly Intake (PTWI) established by FAO/WHO. In addition, the pasteurization process showed effective in reducing microbial load. For the temperature-time conditions 82.5ºC - 45 s and 87.5ºC - 45 s, the number of surviving organisms decreased as the storage period increased. However for the temperature-time conditions 82.5ºC - 35 s and 87.5ºC - 35 s, there was an increase of the number of surviving organisms after 23rd day and 33rd day, respectively, compared to raw orange juice. During the 57 days storage, the yeast and mold count were lower than the maximum acceptable limit established by Brazilian Legislation (104 CFU/mL).