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Towards a precise understanding of service propertiesO'Sullivan, Justin James January 2006 (has links)
This thesis addresses the question of what would be a domain independent taxonomy that is capable of representing the non-functional properties of conventional, electronic and web services. We cover all forms of services, as we prefer not to make any distinction between the three forms. Conventional service descriptions, such as newspaper advertisements, are rich in detail, and it is this richness that we wish to make available to electronic and web service descriptions. In a conventional service context, when we ask a service provider for details, perhaps by phoning the service provider, we are seeking ways to assist with decision making. It is this same decision making or reasoning that we wish to be available to electronic services. Historically, services have always been distinguished according to some criteria of a service requestor. Examples are price, payment alternatives, availability and security. We are motivated to ensure that the criteria used to evaluate conventional services are also available for electronic and web services. We believe that the ability to richly and accurately describe services has significant applicability in the areas of electronic service discovery, dynamic service composition, service comparison, service optimisation, and service management. In particular, the increased level of descriptive depth will also facilitate more thorough decision-making by a service requestor. Whilst we acknowledge the importance of service functionality, this thesis is primarily concerned with the non-functional properties of services. A service is not a function alone. It is a function performed on your behalf at a cost. And the cost is not just some monetary price; it is a whole collection of limitations. This thesis is all about these. We believe that to accurately represent any service, a description requires information relating to both the functionality and the associated constraints. We consider these constraints over the functionality of the service to be non-functional properties. We believe that a service description is only complete once the non-functional aspects are also expressed. We undertook a significant analysis of services from numerous domains. From our analysis we compiled the non-functional properties into a series of 80 conceptual models that we have categorised according to availability (both temporal and locative), payment, price, discounts, obligations, rights, penalties, trust, security, and quality. Our motivation is to provide a theoretical basis for automated service discovery, comparison, selection, and substitution. The need to describe a service is analogous with labelling for goods or products. Product labelling occurs for the safety and benefit of purchasers. Why is the same labelling not afforded for the benefit of service requestors?
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Hidrólise enzimática das proteínas de carne de frangoSchmidt, Cristiano Gautério January 2008 (has links)
Dissertação(mestrado)- Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2008. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-09-17T14:54:36Z
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Previous issue date: 2008 / Enzimas proteolíticas são usadas para obter hidrolisados que possam ser usados como ingredientes funcionais em sistemas alimentícios. A hidrólise das proteínas
alimentares possui uma longa história, principalmente as proteínas vegetais, do leite e de pescado. No entanto, pouco trabalho tem sido feito sobre a hidrólise de proteínas de carne de frango. Por essa razão, o objetivo deste trabalho foi à obtenção de
hidrolisados enzimáticos de peito e coxa de frango, com diferentes graus de hidrólise e
diferentes propriedades funcionais, utilizando as enzimas Alcalase e Flavourzyme.
Para definir quais as variáveis do processo de hidrólise enzimática que influíam no
grau de hidrólise das proteínas, realizou-se um planejamento fatorial 23 completo, para
cada enzima e para cada corte de carne, variando a concentração de substrato [S] de
5 a 10% (p/v) em proteína, a concentração de enzima [E] de 4 a 8% em relação à massa total de proteínas, e o tempo (t) de hidrólise de 60 a 120 minutos, considerando como variável dependente o grau de hidrólise (GH) das proteínas. Os ensaios com a enzima Alcalase resultaram em valores de GH variando de 20,9 a 57,4% em peito de frango e de 18,6 a 38,8% em coxa de frango, enquanto os valores de GH variaram de 17,2 a 40,5% quando foi utilizado peito de frango como substrato e de 8,3 a 22,5% quando se utilizou coxa de frango como substrato, para a enzima Flavourzyme. As
variáveis de processo estudas apresentaram efeitos significativos no GH, em todos os
casos, exceto a concentração de enzima na hidrólise de coxa de frango com Alcalase.
Obtiveram-se modelos matemáticos preditivos a um nível de 5% de significância para
as hidrólises com Alcalase em ambos os substratos, e para a enzima Flavourzyme em
coxa de frango. Com base nos resultados do planejamento experimental, escolheramse
hidrolisados de baixo e alto GH, para ambos os substratos e ambas as enzimas, que foram submetidos a secagem e avaliados pelas suas propriedades de solubilidade, capacidade de retenção de água, capacidade emulsificante, capacidade de retenção de óleo, capacidade de formação de espuma, estabilidade de espuma e digestibilidade. Os hidrolisados obtidos com a enzima Alcalase apresentaram uma maior dificuldade para remoção de umidade durante o processo de secagem do que os hidrolisados
com a enzima Flavourzyme, apresentando valores de constante de secagem (K) e
difusividade efetiva (Def) entre 0,0092 e 0,0125 min-1 e 1,56x10-9 e 2,11x10-9 m2/s. Os
hidrolisados obtidos com a enzima Alcalase apresentaram maiores valores de solubilidade, capacidade de formação de espuma, estabilidade de espuma e de digestibilidade do que os hidrolisados obtidos com a enzima Flavourzyme, que apresentaram maiores valores de capacidade de retenção de água, propriedade emulsificante e capacidade de retenção de óleo. Estimou-se que as diferenças nos valores de grau de hidrólise foram decorrentes das diferenças na matéria-prima utilizada e no modo de atuação das diferentes enzimas proteolíticas. A diversidade de características dos hidrolisados demonstra o potencial de uso como ingredientes alimentícios. / Proteolytic enzymes are used to obtain hydrolysates that can be used as functional
ingredients in food systems. Hydrolysis of food protein has a long history, mainly for
vegetable, milk and fish proteins. However, little work has been done on hydrolysis of
chicken protein. For that reason, the objective of this work was the production of
enzymatic hydrolysates with different degree of hydrolysis and different functional
properties utilizing breast and thight as substrate using two proteolytic enzymes,
Alcalase and Flavourzyme. To define which process variables of the enzymatic hydrolysis would influence the protein degree of hydrolysis, an experimental design(factorial 23) for each enzyme and each meat cut was adopted, varying the substrate concentration [S] from 5 to 10% (w/v) protein-basis; enzyme concentration [E] from 4 to 8% (w/w) total protein-basis; and time (t) from 60 to 120min, considering as dependant variable, the degree of hydrolysis (%DH). The assays done with Alcalase resulted in degree of hydrolysis values varying from 20.9 to 57.4% for breast meat and from 18.6 to 38.8% for thight meat, and from 17.2 to 40.5% when breast meat as substrate was utilized, and from 8.3 to 22.5% when thight meat was used, for Flavourzyme assays. The process variables studies presented significant effects on the degree of hydrolysis, in all the study cases, except the enzyme concentration of the thight meat hydrolysis with Alcalase. It was obtained predictive mathematical models and dimensional response surface relating the variables [S], [E] and (t) with %DH of chicken proteins. Taking the experimental design results in account, hydrolysates with low and high degree of hydrolysis were chosen for both substrates and both enzymes, that were submitted to a drying process and were evaluated for their functional properties of
solubility, water holding capacity, emulsifying capacity, oil holding capacity, foam formation capacity, foam stability and in vitro digestibility. The Alcalase hydrolysates presented difficulty of the water removal when compared with the Flavourzyme hydrolysates, resulting in drying constant (K) and effective diffusivity (Def) values between 0.0092 and 0.0125 min-1, and between 1.56 x 10-9 and 2.11 x 10-9 m2/s,
respectively. The Alcalase hydrolysates presented higher values of solubility, foam
capacity, foam stability and digestibility, when compared with Flavourzyme hydrolysates, which presented higher values of water holding capacity, emulsifying capacity and oil holding capacity. It was considered that the differences between the degree of hydrolysis values was the consequence of the different raw materials utilized as substrate and the different activity and affinity for the substrate presented by the proteolytic enzymes. The diversity of characteristics and properties presented by the chicken protein hydrolysates shows a potential use of these products as food ingredients.
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SYNTHESIS OF NOVEL METAL HALIDES AND THEIR STRUCTURE-PROPERTY RELATIONS / 新規金属ハライドの合成とその構造物性相関Koedtruad, Anucha 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第23023号 / 理博第4700号 / 新制||理||1674(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 島川 祐一, 教授 寺西 利治, 教授 長谷川 健 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
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Physical Treatments To Modify The Functionality Of Carrot Pomace And The Development Of An Enhanced Beef PattyRichards, Jordan O.A 01 September 2023 (has links) (PDF)
Approximately one-third of the global food produced for human consumption is lost or wasted somewhere along the food chain. Carrots are one of the most important and widely produced root vegetables grown worldwide; they are rich in many beneficial bioactive compounds such as dietary fiber and carotenoids. Every year, an estimated 29% of processed carrots are lost as waste. The U.S. is the 3rd largest producer of carrots worldwide, 85% of which come from California. During carrot juice processing, up to 50% of the raw material remains as carrot pomace. Carrot pomace may contain up to 55% total dietary fiber, which is thought to have important functional properties such as water holding and fat binding. The objectives of this project were to: 1) Investigate how physical pretreatment and drying treatment affect the functional and chemical properties of carrot pomace, 2) evaluate the impact that carrot pomace as a functional ingredient will have on the physical and chemical properties of beef patties, and 3) validate the developed beef patties using a consumer sensory test to ensure that the products have acceptable sensory attributes.
High shearing and hydraulic pressing pretreatments (HSHP) increased the swelling capacity of freeze-dried carrot pomace by 59% and dehydrated carrot pomace by 34%. Freeze-dried carrot pomace also retained 33% more carotenoids compared to dehydrated pomace. The drying method significantly impacted the functional properties of carrot pomace. Freeze drying improved the water holding capacity by 22% and fat binding capacity by 194% over dehydrated carrot pomace. The addition of dried carrot pomace increased the cooking yield and water-holding capacity of beef patties by 5-15% and 12%, respectively, without significantly changing their textural properties or chemical composition. Eighty-six (86) consumers took part in sensory testing to evaluate beef patties formulated with carrot pomace. Overall, there were no significant differences in liking scores between the carrot pomace patties at 1% & 3% and the control patty. Scores were not changed significantly when patties were consumed with a bun. These results suggested that carrot pomaces may be physically modified to be utilized as a functional ingredient in the food industry.
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Development of in-situ coated lactose particles during spray dryingBrech, Michael January 2014 (has links)
Lactose is used in many food/pharmaceutical products, despite powders containing amorphous lactose being difficult to handle because they tend to be sticky and are prone to crystallization and powder caking. There is therefore a market for lactose powder with improved functionality to facilitate powder handling. The aim of the proposed project was to produce a value-added, free-flowing and non-caking lactose powder that can be easily blended into other dairy products, such as dry-powder soups or drinks, and non-dairy products such as chocolate bars. The principle of particle coating during spray drying (in-situ coating), which exploits the phenomenon of solute segregation of different components within the drying droplet, was used for the purpose of producing such powders. In this work, spray-dried lactose powders containing low concentrations of edible additives, such as proteins, polymers or fat, were produced in order to investigate the ability of these additives to accumulate at the droplet surface during drying to form a coating that improves powder functional properties and limits powder caking. This thesis presents the results of the trials necessary to develop these coated powder by the use of an
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Preservation of Extra-Functional Properties in Embedded Systems DevelopmentSaadatmand, Mehrdad January 2015 (has links)
The interaction of embedded systems with their environments and their resource limitations make it important to take into account properties such as timing, security, and resource consumption in designing such systems. These so-called Extra-Functional Properties (EFPs) capture and describe the quality and characteristics of a system, and they need to be taken into account from early phases of development and throughout the system's lifecycle. An important challenge in this context is to ensure that the EFPs that are defined at early design phases are actually preserved throughout detailed design phases as well as during the execution of the system on its platform. In this thesis, we provide solutions to help with the preservation of EFPs; targeting both system design phases and system execution on the platform. Starting from requirements, which form the constraints of EFPs, we propose an approach for modeling Non-Functional Requirements (NFRs) and evaluating different design alternatives with respect to the satisfaction of the NFRs. Considering the relationship and trade-off among EFPs, an approach for balancing timing versus security properties is introduced. Our approach enables balancing in two ways: in a static way resulting in a fixed set of components in the design model that are analyzed and thus verified to be balanced with respect to the timing and security properties, and also in a dynamic way during the execution of the system through runtime adaptation. Considering the role of the platform in preservation of EFPs and mitigating possible violations of them, an approach is suggested to enrich the platform with necessary mechanisms to enable monitoring and enforcement of timing properties. In the thesis, we also identify and demonstrate the issues related to accuracy in monitoring EFPs, how accuracy can affect the decisions that are made based on the collected information, and propose a technique to tackle this problem. As another contribution, we also show how runtime monitoring information collected about EFPs can be used to fine-tune design models until a desired set of EFPs are achieved. We have also developed a testing framework which enables automatic generation of test cases in order verify the actual behavior of a system against its desired behavior. On a high level, the contributions of the thesis are thus twofold: proposing methods and techniques to 1) improve maintenance of EFPs within their correct range of values during system design, 2) identify and mitigate possible violations of EFPs at runtime. / CHESS / MBAT / ITS-EASY
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Caracterização físico-química e funcional de amido de tuberosas originárias da América do Sul: oca (Oxalis tuberosas Molina), olluco (Ullucus tuberosus Caldas) e mashua (Tropaeolum tuberosum Ruiz & Pavón) / Physico-chemical and functional characterization of tuber starches originating in South America: oca (Oxalis tuberosa Molina), olluco (Ullucus tuberosus Caldas) and mashua (Tropaeolum tuberosum Ruiz & Pavón)Yamani, Beatriz Valcárcel 25 October 2010 (has links)
A região dos Andes é conhecida por sua grande diversidade genética em vegetais, sobretudo raízes e tubérculos, que apresentam elevado teor de nutrientes. A população rural da região utiliza os tubérculos como alimentos principais do consumo diário, sendo alguns deles a oca (Oxalis tuberosa Molina), o olluco (Ullucos tuberosus Caldas) e a mashua (Tropaeolum tuberosum Ruiz e Pavón), os quais apresentam cores e sabores particulares. Neste trabalho tais alimentos e suas respectivas frações amiláceas foram avaliados quanto à composição. O amido foi caracterizado quanto às propriedades físicas, físico-químicas e funcionais. As amostras obtidas em mercado local de Arequipa - Perú apresentaram diferenças significativas no rendimento de extração do amido. Quando observados por microscopia eletrônica de varredura e microscopia óptica, os grânulos de amido de oca apresentaram morfologia principalmente elipsoide e oval e comprimentos de até 54,30 µm. Grânulos de amido de olluco com comprimentos de até 32,09 µm apresentaram formatos elipsoide, oval, cônico, em forma de pêra e prismático. Os grânulos de amido de mashua com formas esféricas e ovais truncadas apresentaram os menores comprimentos, até 16,29 µm. O conteúdo de fósforo variou: 0,044% (oca), 0,047% (olluco) e 0,081% (mashua). A porcentagem de amilose foi de 27,60 % (oca), 26,49 % (olluco) e 27,44 % (mashua). O amido de olluco apresentou menor poder de intumescimento, formando géis mais opacos e menos duros. Os três amidos mostraram a mesma estabilidade quando mantidos sob refrigeração e apresentaram elevada sinérese sob temperaturas de congelamento, com variação de 40,28% até 74,42 % para amido de olluco. Os amidos apresentaram fácil cozimento, com elevados picos de viscosidade. Estas baixas temperaturas de gelatinização e a elevada estabilidade durante a refrigeração fazem destes amidos matérias-primas apropriadas para uso em diversos produtos e formulações que requeiram temperaturas brandas de processamento e que prescindam de congelamento. / The Andean region is known for its great genetic diversity in plants, especially roots and tubers, which have a high nutrient content. The rural population on the region consumes them as staple food daily. Oca (Oxalis tuberosa Molina), olluco (Ullucos tuberosus Caldas) and mashua (Tropaeolum tuberosum Ruiz & Pavón) are the most consumed which are characterized by distinct colors and flavors. In the present work, these foods and their starchy fractions were evaluated in relation to its composition. Starch physical, physical-chemical and functional properties were characterized. Samples obtained from a local market in Arequipa - Peru showed significant differences in starch extraction yield. When observed by scanning electron microscopy and optical microscopy, oca starch granules showed morphology mainly ellipsoidal and oval, with sizes up to 54.30 µm. The olluco starch granules had sizes up to 32.09 µm with ellipsoid, oval, conical, pear-shaped and prismatic shapes. Mashua starch granules with spherical and oval truncated shapes showed smaller dimensions up to 16.29 µm. The phosphorus content varied: 0,044% (oca), 0,047% (olluco) and 0,081% (mashua). The percentage of amylose was 27.60 % (oca), 26.49 % (olluco) and 27.44 % (mashua). Olluco starch showed lower swelling power forming gels more opaque and less hardness. The three starches exhibited the same stability when kept under refrigeration and showed higher syneresis under freezing temperatures, with a variation of 40,28 % to 74.42 % for olluco starch. The results showed easy cooking starches with high peak viscosity. These low temperatures of gelatinization and high stability during the refrigeration make these starches suitable for use in various products and formulations that require milder processing temperatures but without freezing.
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Características estruturais, físico-químicas e funcionais dos amidos de mandioca e de milho com diferentes teores de amilose oxidados por ozônio / Structural, physico-chemical and functional characteristics of cassava starch and corn starches with different levels of amylose oxidized by ozoneMatta Junior, Manoel Divino da 03 September 2015 (has links)
A oxidação é um método que visa a modificação do amido por agentes oxidantes diversos, introduzindo grupamentos funcionais e realizando cisão das ligações glicosídicas. Seus objetivos são reduzir a viscosidade do polissacarídeo, elevar a transparência da pasta e limitar sua retrogradação. O objetivo do presente estudo foi modificar os amidos de milho com diferentes teores de amilose e o amido de mandioca pelo tratamento com ozônio e também caracterizar as amostras oxidadas quanto às características moleculares, estruturais e funcionais, correlacionando-as entre si. O processo de oxidação foi efetivo em alterar diversas propriedades e funcionalidades dos amidos estudados, contudo de modos distintos para as diferentes fontes. Tais diferenças decorrem da composição e estrutura granular peculiares de cada um, promovendo diferentes taxas de degradação das lamelas amorfas e cristalinas e da presença de grupos carboxilas. A oxidação pelo ozônio nas condições estudadas reduziu a viscosidade apenas do amido de milho normal; no caso dos amidos de milho ceroso e de mandioca, a viscosidade foi ligeiramente aumentada. O amido de milho de alta amilose não apresentou viscosidade nas condições de analisadas pelo Rapid Visco Analyser, tanto antes como após a oxidação. O setback foi reduzido pelo processo oxidativo com o ozônio para os três amidos, tornando-os mais estáveis. A oxidação aumentou a claridade de pasta de todos os amidos. A ozonização também causou alterações no amido de milho ceroso e no de mandioca, de modo a proporcionar capacidade de expansão no forno, em índices próximos àqueles de amostras comerciais de polvilho azedo. Os demais amidos não se expandiram significativamente. A propriedade de expansão no forno foi afetada principalmente pela variação de entalpia de gelatinização dos amidos, mas também pelos teores de carboxilas e de carbonilas, fator de inchamento, quebra de viscosidade, setback, cristalinidade relativa e tamanho das cadeias ramificadas de amilopectina (cadeias B2 e B3 e tamanho médio). O uso do ozônio, portanto, poderá ser útil nesta modalidade de modificação dos amidos e, em especial para o amido de mandioca ou de milho ceroso, capacitando-os para a expansão no forno, o que poderia gerar produtos panificáveis mais padronizados do que os obtidos pelo polvilho azedo, ou sem as consequências da oxidação por métodos químicos mais agressivos, como o uso do hipoclorito de sódio. / Oxidation is a method which aims the starch modification by various oxidizing agents, introducing functional groups and performing the cleavage of glycosidic linkages. Its objectives are to reduce the polysaccharides viscosity, raising the transparency paste and minimizing retrogradation. The aim of this study was to modify the corn starch with different levels of amylose and the cassava starch using ozone and also to characterize the samples oxidized as the molecular, structural and functional characteristics, relating them with each other. The oxidation process was effective changing several properties and features of the studied starches, however, in different ways for the different sources. These differences come from having starches different composition and granular structure, providing different rates of degradation of amorphous and crystalline lamellae and the presence of carbonyl groups, and carboxyl formed. A reduction in viscosity was observed for the normal corn starch after oxidation, and an increase for the waxy maize and cassava starches. The high amylose corn starch showed no viscosity by Rapid Visco Analyser, before or after oxidation. The setback was reduced by the oxidation process with ozone for the three starches, rendering them more stable. Oxidation by ozone under the conditions studied increased paste clarity of all starches. Ozonation caused changes in the waxy corn and cassava starches, providing baking properties, in indices close to those of commercial samples of sour cassava starch. The other starches are not expanded significantly in the oven. The baking property was mostly affected by enthalpy of gelatinization of starches, but also by carboxyl and carbonyl contents, swelling factor, breakdown, setback, relative crystallinity and size of amylopectin branched chains (B2, B3 and medium size). So, the use of ozone may be useful in this starch modification modality, and in particular for cassava or waxy maize starches, enabling the expansion in oven, which could generate more standardized baking products than those obtained by sour cassava starch, or without consequences of oxidation using more aggressive chemical methods, such as sodium hypochlorite.
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Isolado protéico de farinha de semente de goiaba (Psidium guajava) : caracterização de propriedades funcionais e térmicas /Fontanari, Gustavo Guadagnucci. January 2006 (has links)
Orientador: José Paschoal Batistuti / Banca: Maria Helena Martini / Banca: Valdir Augusto Neves / Banca: José Alfredo Gomes Arêas / Banca: João Bosco Faria / Resumo: A partir da farinha da semente de goiaba (Psidium guajava), cuja composição centesimal é de aproximadamente 6,17 l 0,04% de umidade, 8,43 l 0,12% de proteína e alto teor de fibras, 60,88 l 0,9%, obteve-se isolado protéico (IP) através da precipitação isoelétrica (pI 4,5), cuja fração majoritária pertence à classe das glutelinas. As condições para o preparo do IP foram definidas a partir da curva de solubilidade em água x pH e temperatura de 25 l 3 ºC. Tais condições permitiram obter isolados protéicos com rendimento de extração de 45,2 l 0,5% (pH10,0) e 66,2 l 0,5% (pH11,5) e elevado conteúdo protéico 96,4 l 0,5% e 93,5 l 0,4% respectivamente. A capacidade de absorção de água e óleo foram baixas, apresentando 1,05 l 0,07 e 2,3 l 0,01 mL/g proteína respectivamente para IP 10,0 e 1,65 l 0,07 e 1,70 l 0,07 mL/g pr oteína respectivamente para IP 11,5. A maior capacidade de emulsificação, foi observado para o IP 11,5, 140 l 8 g óleo/g prot., comparado com o IP 10,0, 37 l 2 g óleo/g prot. A formação de gel foi observada em pH neutro e ausência de sal, apresentando as concentrações de 8% para IP 10,0 e 10% para IP 11,5. A cromatografia revelou a presença de dois picos para ambos isolados com sete frações de proteínas de diferentes pesos moleculares. As curvas TG-DTG / DSC revelaram maior quantidade de água para o IP 10,0 e elevada temperatura de estabilidade térmica 200 oC para ambos isolados. / Abstract: From the guava seed flour (Psidium guajava), whose centesimal composition belongs to about 6,17 ??0,04% of moisture, 8,43 ??0,12% of protein and high content of fibers, 60,88 ??0,9%, the protein isolate (PI) was obtained through the isoelectric precipitation (Ip 4,5) whose majority belongs to glutelins class proteins. The conditions for the preparation of the PI was defined from the solubility curve in water x pH and temperature of 25 ??3ºC. Such conditions allowed to obtain protein isolated with extraction yield of 45,2 ??0,5% (pH10,0) and 66,2 ??0,5% (pH11,5) and high protein content of 96,4 ??0,5% and 93,5 ??0,4% respectively. The absorption capacity for water and oil were low, showing 1,05 l 0,07 and 2,3 l 0,01 mL/g protein, respectively, for PI 10,0 and 1,65 l 0,07 and 1,70 l 0,07 mL/g protein, respectively, for PI 11,5. The most emulsification capacity was observed for PI 11,5 (140 l 8 g oil/g prot.), compared to PI 10,0 (37 l 2 g oil/g prot.). The gel formation was observed in neutral pH and salt absence, showing the concentrations of 8% to PI 10,0 and 10% to PI 11,5. The chromatography shows the presence of two peaks for both protein isolated with seven fractions of proteins with different molecular weights. The curves of TG-DTG / DSC revealed high water quantity for PI 10,0 and high temperature for thermal stability 200 °C for both isolates. / Mestre
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Izučavanje funkcionalnih svojstava enzimski modifikovanih biljnih globulina / Investigation of the functional properties of enzymatic modified plant globulinsPopović Ljiljana 19 April 2012 (has links)
<p>Predmet doktorske disertacije je izučavanje različitih bioprocesa za modifikovanje biljnih globulina radi unapređenja njihovih funkcionalnih karakteristika. Istraživanja su zasnovana na karakterizaciji i enzimskoj modifikaciji glavnog rezervnog proteina (12S), kukurbitina, iz semena uljane tikve (<em>Cucurbita pepo</em>). Osnova istraživanja je enzimska konverzija globulina i dobijanje proteinskih modifikata delovanjem hidrolaza i transferaza. U okviru istraživanja, enzimski procesi modifikacije globulina izučavani su sa dva aspekta: enzimska hidroliza i enzimsko umrežavanje (cross-linking), primenom komercijalnih enzimskih preparata. Takođe istraživanja obuhvataju i razvoj i kontrolu samih bioprocesa definisanjem i optimizacijom procesnih parametara (temperature, pH, koncentracije enzima i supstrata, vreme reakcije). Ovako definisani procesi eksploatisani su u cilju kreiranja željenih funkcionalnih karakteristika proteina spram njihove potencijalne primene u formulacijama hrane. Odabir i optimizacija procesnih parametara i modelovanje bioprocesa izvedeno je implementiranjem nove kompjuterske i analitičke metodologije</p> / <p>The PhD thesis research is aimed at development of different bioprocesses for modification of plant globulins in order to improve their functional properties. Studies are based on characterization and enzymatic modification of major storage protein (12S), cucurbitin derived from pumpkin oil seed (<em>Cucurbita pepo</em>). The base of research is enzymatic conversion of cucurbitin by hydrolase and transferase. Two different enzymatic processes are used for protein modification: (i) enzymatic hydrolysis and (ii) enzymatic cross-linking. To monitor, control the bioprocesses, and definition of process parameters, such as temperature, pH, enzyme-substrate ratio, reaction time, Response Surface Methodology (RSM) was used. In addition, RSM was employed for production of protein modification with desired functional properties.</p>
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