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Innovative methods to control the viscosity and turbulence in the flow of liquid suspension can be engineered by way of incorporating the concepts of electric and magnetic field into the rheology of complex fluids. Rheology of liquid Chocolate is a very crucial factor in determining the cost of manufacturing process as well as formulating varieties of end consumer products, for example, containing less fat. We have invented a method to lower the viscosity of liquid chocolate flow with the application of electric field. In the lab, we have found that viscosity of chocolate samples is reduced by 40~50% with our method. Thus, fat content in those samples can be reduced by 10% or more. Therefore, we expect to see much healthier and tastier chocolate product in the market once this technology gets implemented in commercial manufacturing. High viscosity and turbulence in blood flow greatly increase the risk of cardiac diseases. Hence, discovering new method to address turbulence suppression and viscosity reduction is critically important. In our study, we have found that in the in-vitro experiment, if blood is subjected to flow through a channel placed inside a strong magnetic field, its viscosity reduces by 10~20%. Based on these findings, a Megneto-Rheology (MR) therapeutic device has been developed to examine the effect on the blood pressure in human subjects. Preliminary clinical trials show that application of this MR therapy reduces blood pressure by 10% or more. In this thesis, above mentioned inventions for the flow of Blood and liquid Chocolate will be thoroughly discussed. / Physics / Accompanied by two .mpeg4 files.

An investigation has been carried out into the rheology of chocolate in relation to its flow and mixing features in a real industrial environment. The chocolate manufacturing plant of Rowntree at York provided a base for this study. The project aims were: a) to measure the viscous and time dependent properties of chocolate. b) to explain the observed flow properties in relation to the constituents of chocolate. c) to determine the shear rate which, for a given recipe, yields a minimum stable viscosity (of particular commercial value). d) to assess the type of mixer able to provide this duty. The experimental work involved rheological studies with concentric cylinder and tubular viscometers, operated to measure viscosity as a function of shear rate and shearing time. The chocolate samples studied were taken from various points in the manufacture process at Rowntree, York. Model chocolate systems were made from cocoa liquor, and sugar with cocoa butter, which were studied to underpin the basic mechanisms of the flow properties of the total chocolate. Shear thinning in milk chocolate has been shown to be accounted for by surface coating and fat release from the cocoa cellular material. Analysis of the sugar and cocoa butter system gave large hysteresis loops which may be explained as due to agglomeration of the sugar particles. The level of hysteresis was found to be related to the polarity of the liquid phase, such that a more polar fluid results in less hysteresis. Laboratory experiments have revealed that the level of work input to give permanent viscosity reduction for milk chocolate is dependent on the measuring shear rate. The level of optimum shear input for the measuring range 10 to 130 sec 1 is 645 sec for 30 minutes. The apparent viscosity measured at lower shear rates requires much longer ([approx]100 minutes). / Yorkreco, Nester York Ltd.

This thesis examines the trope of hunger in Cuban cinema produced during the socio-economic context known as the Special Period. Films selected for this discussion are Fresa y chocolate (1993) by Tomás Gutiérrez Alea and Juan Carlos Tabío, and El Rey de La Habana (2015) by Agustí Villaronga. Focused on the analysis of the trope of hunger, this study offers a summary of the Cuban cultural manifestations of the last decades that have addressed the issue of hunger as well as a brief historical context that allows us to understand the development of this trope from 1960 to the present. Focused on the aforementioned films, this study has observed the aesthetic and stylistic particularities used in filmic representations to convey the island's shortcomings. The thesis demonstrates the existence of two main famines within Cuban society: cultural hunger and physiological hunger. Cultural hunger is studied in Fresa y chocolate as a direct consequence of the cultural control of the repressive ideological apparatus implanted in the sixties. The analysis of El Rey de la Habana shows how physiological hunger builds a marginal and abject subject, unable to escape the vicious circle that society has imposed on him. / Master of Arts / This thesis examines the trope of hunger in Cuban cinema produced during the socio-economic context known as the Special Period. Films selected for this discussion are Fresa y chocolate (1993) by Tomás Gutiérrez Alea and Juan Carlos Tabío, and El Rey de La Habana (2015) by Agustí Villaronga. The trope of hunger in these films is analyzed in its multiple manifestations, whether literal or figurative, paying special attention to the aesthetic and stylistic particularities that they use to convey the island's shortcomings.

El objetivo general de la presente tesis fue estudiar el proceso de cristalización y polimorfismo de la manteca de cacao (MC) en la cadena de fabricación de chocolate oscuro a partir de cacao (Theobroma cacao L.) variedad Criollo. La revisión de la literatura demostró que en la cadena de fabricación de chocolates, la fermentación del cacao es la etapa más importante porque genera el perfil aromático; pero, puede influir en la cristalización y polimorfismo de la MC y por tanto en la cadena de fabricación del chocolate, hipótesis que fue establecida a partir del análisis bibliométrico. Para la evaluación de la cristalización, polimorfismo y miscibilidad de la MC se usó Calorimetría Diferencial de Barrido (DSC) y Microscopía Confocal Raman (CRM). Durante la fermentación espontánea se pudo notar que el cacao alcanzó su temperatura más alta (45,35 °C) a los siete días, periodo durante el cual pudo determinarse los parámetros cinéticos de cristalización de la MC en el interior del grano usando DSC y la teoría de Avrami. Se encontró que durante el proceso de fermentación se produjeron núcleos de cristales metaestables (B1’ y B2’) de MC, los cuales crecieron de manera espontánea o esporádica, en forma de plato, varillas o agujas. La técnica multivariada k-means identificó patrones que dividieron la fermentación en dos etapas: en la primera (0 – 3 días), la MC cristalizó en 15,78 minutos y en la segunda (4 – 7 días) cristalizó en 17,88 minutos, por ello se propuso un proceso de fermentación de solo tres días para cacao Criollo. Para la fabricación de chocolate fue necesario implementar una etapa previa que consistió en analizar la miscibilidad de la MC con aceite de coco (CNO) y aceite de sacha inchi (SIO). Entonces, se preparó equivalentes de manteca de cacao (CBE) mezclando la MC con cada uno de los aceites vegetales en diferentes concentraciones. Los espectros Raman mostraron que SIO se diferenció de CNO y MC por su alta proporción de insaturación, evidenciado por la alta intensidad del pico a 1662,7 cm-1. Los picos a 1745,4 cm-1 y 1733,8 cm-1 en la MC evidenciaron la existencia de las formas B2’ y B1’. Las imágenes químicas Raman y la técnica Resolución de Curva Multivariada-Mínimos Cuadrados Alternantes generaron mapas de distribución e histogramas para determinar cualitativamente la miscibilidad del aceite vegetal con la MC, mientras que con estudio se calculó la desviación estándar relativa para determinar la miscibilidad de manera cuantitativa. Ambas técnicas mostraron que mezclar MC con CNO en proporciones de 55/45 y MC con SIO en proporciones de 65/35 pueden generar CBE con alta miscibilidad, la cual se reduce al incrementar la proporción de MC. La cinética de cristalización isotérmica develó que SIO cristaliza a temperaturas inferiores a cero grados y al igual que CNO, sus propiedades térmicas se modificaron cuando fueron mezclados con la MC para formar su correspondiente CBE. CNO cristalizó más rápido que la MC, pero al mezclarse con ésta, su velocidad de cristalización y entalpía de fusión se redujeron. Finalmente, estos CBEs fueron utilizados en combinación con el régimen de temperado para producir dos tipos de chocolates oscuros (Ch-SIO y Ch-CNO), evaluando su cinética de cristalización, polimorfismo, propiedades físicas y térmicas del producto final. La velocidad de cristalización de la MC incrementó como consecuencia de los CBE y temperado, obteniendo una cristalización más rápida en el Ch-SIO (7,08 ± 0,15 min) que en el Ch-CNO (7,25 ± 0,18 min). Ambos factores produjeron chocolates con altos porcentajes de forma B2 (92,56 ± 1,49% en Ch-SIO y 90,3 ± 1,18% en Ch-CNO) que superan los valores establecidos en literatura. La presencia de esta forma polimórfica fue corroborada con los bajos valores del índice de blancura (27,55 ± 0,22 – 28,73 ± 0,54). Las propiedades físicas y térmicas de los chocolates cambiaron dentro de valores aceptables.

Achocolatados e bebidas achocolatadas são alimentos muito consumidos em praticamente todos os países, especialmente por crianças e jovens. Isso porque o chocolate é também reconhecido como um agente flavorizante largamente aceito. O objetivo geral deste trabalho foi elaborar um estudo de achocolatados e de bebidas achocolatadas disponíveis no mercado brasileiro, desenvolvendo-se técnicas de análises e obtendo-se resultados com finalidades comparativas. Ainda formulou-se bebida achocolatada com características funcionais, utilizando-se para tal quitosana modificada desenvolvida no Departamento de Tecnologia Bioquímico-Farmacêutica. Este trabalho foi dividido em duas partes, para melhor leitura e compreensão: parte 1: Achocolatados e parte 2: Bebidas achocolatadas. Para os achocolatados foram realizadas análises em produtos disponíveis no mercado brasileiro, como: composição centesimal, teobromina, alcalóides totais e pH. Procurou-se enfatizar as diferenças entre os produtos para finalidades especiais (\"diet\" e \"light\") e os tradicionais. Ainda, estudou-se propriedades tisicas, como força de compactação, densidade e granulometria, observando a correlação entre estas. Para bebidas achocolatadas, desenvolveu-se produto com quitosana modificada, atribuindo ao produto características funcionais. Estudou-se a reologia deste produto e de outros obtidos no mercado brasileiro, avaliando-se assim o produto desenvolvido. O teor de sólidos solúveis avaliado nestas amostras, com resultados muito próximos, sugeriu certa padronização na adição de leite, açúcar e sólidos de cacau em suas formulações. Para a bebida desenvolvida, aplicou-se teste sensorial ( aceitação global e viscosidade), utilizando-se como comparativo bebida do mercado brasileiro (Chocomilk), escolhida por ser comercializada em embalagem de vidro (semelhante à do produto em estudo). A aceitação global não demonstrou diferença significativa (P>0,05) entre as amostras, porém a característica mais encorpada da bebida desenvolvida apontou maior tendência de aceitação neste parâmetro. / Chocolate drink powders and chocolate beverages are very consumed foods in almost every contry, specially by children and young people. That is because chocolate is also recognized as a flavour agent greatly accepted. The aim of this work was to elaborate a study of chocolate drink: powders and chocolate beverages from Brazilian market, developing analytical techniques and obtaining results with comparatives purposes. It was developed chocolate beverage with functional characteristics, using for that modified chitosan, developed in this Department. This work was divided into two parts to a better reading and understanding: part 1: Chocolate drink: powders and part 2: Chocolate beverages. In the first part, some chemical analysis were carried out in the products from Brazilian market, such as lipids, proteins ashes, moisture, theobromine and total alkaloids content and the pH. It was emphasized the differences between diet, light and the standard products; The theobromine and total alkaloids content was used as an indicative of the differences. Some physical analysis in the chocolate drink powders were carried out, such as compaction of powder, particle size distribution and poured density of powder. In the second part, it was carried out rheological analysis of the products from the market. It was developed chocolate beverage with modified chitosan as a thickening agent, what gave it a functional characteristic. The rheological characteristics of the developed product were similar to that of the products from the market. Soluble solids analysis was carried out, also making a comparison between the developed product and the products from the market. The results were very similar, showing a standardization of the quantity of sugar, milk and cocoa solids in their formulation. Besides that, it was carried out sensory analysis, with an acceptance test of the developed product and the beverage chosen for comparison - Chocomilk. With the marks of acceptance test (global acceptance and viscosity) it was made a comparison between the two samples. It was noticed that the developed sample was more accepted than the other one, talking about the viscosity, and in talking about the global acceptance, there wasn\'t significant difference (P>0,05) between the samples.

Bombom é o produto constituído por massa de chocolate ou por um núcleo formado de recheios diversos, recobertos por uma camada de chocolate. Alimentos para fins especiais (diet) são aqueles nos quais ocorrem modificações no conteúdo de nutrientes, e são adequados à utilização em dietas diferenciadas, atendendo às necessidades de pessoas em condições metabólicas e fisiológicas específicas. O termo light pode ser utilizado quando for cumprido o atributo de redução mínima de 25% no valor energético total ou no conteúdo de nutrientes de alimentos comparados. Propriedade funcional é aquela relativa ao papel metabólico ou fisiológico que o nutriente ou não nutriente tem nas funções do organismo humano. O presente trabalho visou o desenvolvimento de recheios diet e light para bombons com adição de ingrediente com propriedade funcional (inulina). Foram desenvolvidos um bombom controle e dez formulações de bombom diet e light, sendo apenas uma (F9) selecionada. Um bombom comercial foi utilizado como referência. Foram feitas as análises de atividade de água, pH, umidade, lipídios totais, proteína, fibra alimentar, carboidrato por diferença, perfil de textura (dupla compressão, em analisador de textura TA-XT2) em diferentes temperaturas e tempos de armazenamento. Os bombons (controle e F9) foram comparados através de análise sensorial, sendo apresentados como amostras independentes em um teste de aceitação com escala hedônica híbrida. A substituição dos açúcares por edulcorantes e agentes de corpo foi satisfatória, assim como o uso do substituto de gordura Benefat®. A inulina Raftiline® ST apresentou textura melhor que a inulina Raftiline® HP-Gel, não sendo percebida na boca. A análise do perfil de textura mostrou que o bombom comercial e o de controle apresentaram maior durabilidade que o bombom F9, que apresentou perda de dureza e aumento da mastigabilidade. Na análise sensorial, o bombom F9 obteve altos níveis de intenção de compra, podendo nesta análise ser considerado como um produto de grande potencial de mercado. / Chocolate confectionery is a product consisting of either chocolate mass or a nucleus containing several fillings covered with a chocolate layer. Food for special purposes are those in which modifications are made in what is related to the nutrients content, adapted to the utilization in differentiated diets, in order to fulfill the needs of people showing specific metabolic and physiological disorders. The term light is applied to a product providing it accomplishes the attribute of a 25% minimum reduction in the total energetic value or nutrients content if compared to a similar, standard product. The functional property is relative to the metabolic or physiological role (function) the nutrient or the non-nutrient plays in the human organism o The present work aimed at the development of diet and light fillings for chocolate confectionery using an ingredient (inulin) with a functional property. Two series of chocolate confectionery samples were prepared: a control sample and ten diet and light formulations. One of these formulations, F9, was selected. A commercial chocolate confectionery was used as reference. Analyses were performed to evaluate the water activity, pH, humidity, total lipids, protein, carbohydrate per difference (including fibers), texture profile (double compression, using a texturometer HAS-XT2) in several controlled environments at different temperatures and stored during different periods of time. The chocolate confectionery samples (Control and F9) were compared using sensorial analysis. Independent samples were offered in an acceptance test with hedonic hybrid scale. The substitution of sugars by sweeteners and body agents was satisfactory, as well as the use of a fat substitute, Benefat®. The Inulin Raftiline® ST presented better texture than the Inulin Raftiline® HP-Gel, but no difference was noticed on the mouth feel test. The texture profile showed that both the commercial and the control chocolate confectionery samples presented longer durability than the F9 sample, which presented increased hardness and loss of chewiness. In the sensorial analysis, the chocolate confectionery F9 obtained high levels of purchase intention and thus can be considered as a great product from a market potential point of view.

Bombom é o produto constituído por massa de chocolate ou por um núcleo formado de recheios diversos, recobertos por uma camada de chocolate. Alimentos para fins especiais (diet) são aqueles nos quais ocorrem modificações no conteúdo de nutrientes, e são adequados à utilização em dietas diferenciadas, atendendo às necessidades de pessoas em condições metabólicas e fisiológicas específicas. O termo light pode ser utilizado quando for cumprido o atributo de redução mínima de 25% no valor energético total ou no conteúdo de nutrientes de alimentos comparados. Propriedade funcional é aquela relativa ao papel metabólico ou fisiológico que o nutriente ou não nutriente tem nas funções do organismo humano. O presente trabalho visou o desenvolvimento de recheios diet e light para bombons com adição de ingrediente com propriedade funcional (inulina). Foram desenvolvidos um bombom controle e dez formulações de bombom diet e light, sendo apenas uma (F9) selecionada. Um bombom comercial foi utilizado como referência. Foram feitas as análises de atividade de água, pH, umidade, lipídios totais, proteína, fibra alimentar, carboidrato por diferença, perfil de textura (dupla compressão, em analisador de textura TA-XT2) em diferentes temperaturas e tempos de armazenamento. Os bombons (controle e F9) foram comparados através de análise sensorial, sendo apresentados como amostras independentes em um teste de aceitação com escala hedônica híbrida. A substituição dos açúcares por edulcorantes e agentes de corpo foi satisfatória, assim como o uso do substituto de gordura Benefat®. A inulina Raftiline® ST apresentou textura melhor que a inulina Raftiline® HP-Gel, não sendo percebida na boca. A análise do perfil de textura mostrou que o bombom comercial e o de controle apresentaram maior durabilidade que o bombom F9, que apresentou perda de dureza e aumento da mastigabilidade. Na análise sensorial, o bombom F9 obteve altos níveis de intenção de compra, podendo nesta análise ser considerado como um produto de grande potencial de mercado. / Chocolate confectionery is a product consisting of either chocolate mass or a nucleus containing several fillings covered with a chocolate layer. Food for special purposes are those in which modifications are made in what is related to the nutrients content, adapted to the utilization in differentiated diets, in order to fulfill the needs of people showing specific metabolic and physiological disorders. The term light is applied to a product providing it accomplishes the attribute of a 25% minimum reduction in the total energetic value or nutrients content if compared to a similar, standard product. The functional property is relative to the metabolic or physiological role (function) the nutrient or the non-nutrient plays in the human organism o The present work aimed at the development of diet and light fillings for chocolate confectionery using an ingredient (inulin) with a functional property. Two series of chocolate confectionery samples were prepared: a control sample and ten diet and light formulations. One of these formulations, F9, was selected. A commercial chocolate confectionery was used as reference. Analyses were performed to evaluate the water activity, pH, humidity, total lipids, protein, carbohydrate per difference (including fibers), texture profile (double compression, using a texturometer HAS-XT2) in several controlled environments at different temperatures and stored during different periods of time. The chocolate confectionery samples (Control and F9) were compared using sensorial analysis. Independent samples were offered in an acceptance test with hedonic hybrid scale. The substitution of sugars by sweeteners and body agents was satisfactory, as well as the use of a fat substitute, Benefat®. The Inulin Raftiline® ST presented better texture than the Inulin Raftiline® HP-Gel, but no difference was noticed on the mouth feel test. The texture profile showed that both the commercial and the control chocolate confectionery samples presented longer durability than the F9 sample, which presented increased hardness and loss of chewiness. In the sensorial analysis, the chocolate confectionery F9 obtained high levels of purchase intention and thus can be considered as a great product from a market potential point of view.

Achocolatados e bebidas achocolatadas são alimentos muito consumidos em praticamente todos os países, especialmente por crianças e jovens. Isso porque o chocolate é também reconhecido como um agente flavorizante largamente aceito. O objetivo geral deste trabalho foi elaborar um estudo de achocolatados e de bebidas achocolatadas disponíveis no mercado brasileiro, desenvolvendo-se técnicas de análises e obtendo-se resultados com finalidades comparativas. Ainda formulou-se bebida achocolatada com características funcionais, utilizando-se para tal quitosana modificada desenvolvida no Departamento de Tecnologia Bioquímico-Farmacêutica. Este trabalho foi dividido em duas partes, para melhor leitura e compreensão: parte 1: Achocolatados e parte 2: Bebidas achocolatadas. Para os achocolatados foram realizadas análises em produtos disponíveis no mercado brasileiro, como: composição centesimal, teobromina, alcalóides totais e pH. Procurou-se enfatizar as diferenças entre os produtos para finalidades especiais (\"diet\" e \"light\") e os tradicionais. Ainda, estudou-se propriedades tisicas, como força de compactação, densidade e granulometria, observando a correlação entre estas. Para bebidas achocolatadas, desenvolveu-se produto com quitosana modificada, atribuindo ao produto características funcionais. Estudou-se a reologia deste produto e de outros obtidos no mercado brasileiro, avaliando-se assim o produto desenvolvido. O teor de sólidos solúveis avaliado nestas amostras, com resultados muito próximos, sugeriu certa padronização na adição de leite, açúcar e sólidos de cacau em suas formulações. Para a bebida desenvolvida, aplicou-se teste sensorial ( aceitação global e viscosidade), utilizando-se como comparativo bebida do mercado brasileiro (Chocomilk), escolhida por ser comercializada em embalagem de vidro (semelhante à do produto em estudo). A aceitação global não demonstrou diferença significativa (P>0,05) entre as amostras, porém a característica mais encorpada da bebida desenvolvida apontou maior tendência de aceitação neste parâmetro. / Chocolate drink powders and chocolate beverages are very consumed foods in almost every contry, specially by children and young people. That is because chocolate is also recognized as a flavour agent greatly accepted. The aim of this work was to elaborate a study of chocolate drink: powders and chocolate beverages from Brazilian market, developing analytical techniques and obtaining results with comparatives purposes. It was developed chocolate beverage with functional characteristics, using for that modified chitosan, developed in this Department. This work was divided into two parts to a better reading and understanding: part 1: Chocolate drink: powders and part 2: Chocolate beverages. In the first part, some chemical analysis were carried out in the products from Brazilian market, such as lipids, proteins ashes, moisture, theobromine and total alkaloids content and the pH. It was emphasized the differences between diet, light and the standard products; The theobromine and total alkaloids content was used as an indicative of the differences. Some physical analysis in the chocolate drink powders were carried out, such as compaction of powder, particle size distribution and poured density of powder. In the second part, it was carried out rheological analysis of the products from the market. It was developed chocolate beverage with modified chitosan as a thickening agent, what gave it a functional characteristic. The rheological characteristics of the developed product were similar to that of the products from the market. Soluble solids analysis was carried out, also making a comparison between the developed product and the products from the market. The results were very similar, showing a standardization of the quantity of sugar, milk and cocoa solids in their formulation. Besides that, it was carried out sensory analysis, with an acceptance test of the developed product and the beverage chosen for comparison - Chocomilk. With the marks of acceptance test (global acceptance and viscosity) it was made a comparison between the two samples. It was noticed that the developed sample was more accepted than the other one, talking about the viscosity, and in talking about the global acceptance, there wasn\'t significant difference (P>0,05) between the samples.