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EFFECT OF ENZYMATIC TREATMENTS ON CARBOHYDRATE MATRICES TOWARDS HEALTHY GLUTEN FREE FOODS APPLICATIONDurá de Miguel, Ángela 06 April 2017 (has links)
Starch is the major energy reserve in plants, extensively present in many food and non-food applications, and is one of the most abundant carbohydrates in human diet. In addition to starch native form currently used as a raw material for industrial applications, modified starches have become very attractive to develop numerous products that have greatly expanded starch use and utility. Enzymatic modifications are carried out to enhance starch functionality with the aim of overcoming technological constraints and to improve final product quality. Above all starches, corn starch is widely produced and consumed, and used as main ingredient to produce gluten-free products. This Thesis focuses to the study of the individual effect of three different enzymes, fungal alpha-amylase, amyloglucosidase and cyclodextrin glycosyltransferase, on the above sub-gelatinization temperature of corn starch, in order to modify its properties and extend its applications. Different analyses have been performed to improve the understanding of functional and structural changes promoted by the enzyme action. Moreover, corn starch modified with cyclodextrin glycosyltransferase was selected to investigate the glycemic response in mice. The presence/absence of hydrolysis products released from the enzyme catalytic activity and gelatinization properties were related to glycemic index. Enzymatically modified corn starch resulted in a diversity of functional starch granules that may be used in food applications for many purposes. / El almidón es la principal fuente de reserva de energía en las plantas, está ampliamente presente en diversas aplicaciones alimentarias y no alimentarias, y constituye uno de los hidratos de carbono más abundantes en la dieta humana. Además del uso frecuente y clásico del almidón nativo como materia prima en la producción de alimentos, los almidones modificados han experimentado gran expansión en el desarrollo de numerosos productos debido a su carácter versátil. Las modificaciones enzimáticas se llevan a cabo para realzar la funcionalidad del almidón con objeto de soslayar las restricciones tecnológicas y mejorar la calidad del producto final. En concreto, el almidón de maíz ampliamente producido y consumido, es apropiado como ingrediente principal en la producción de alimentos libres de gluten. Esta Tesis aborda el estudio del efecto individual de tres diferentes enzimas, alfa-amylasa fúngica, amiloglucosidasa y ciclodextrina glucosiltransferasa, sobre la temperatura de sub-gelatinización del almidón de maíz. Se realizaron diferentes análisis para ampliar el conocimiento de los cambios estructurales y funcionales asociados a la acción de la enzima. Así mismo, se seleccionó el almidón de maíz modificado con ciclodextrina glucosiltransferasa para investigar la respuesta glicémica en ratones. El índice glicémico se relacionó con la ausencia/presencia de productos de hidrólisis liberados por la acción catalítica de la enzima y las propiedades de gelatinización. Los almidones de maíz enzimáticamente modificados presentaron alteraciones funcionales en los gránulos de almidón, lo que les confiere características de interés para diversos usos alimentarios. / El midó és la principal font de reserva d'energia en les plantes, està àmpliament present en diverses aplicacions alimentàries i no alimentàries, i constitueix un dels hidrats de carboni més abundants en la dieta humana. A més de l'ús freqüent i clàssic del midó natiu com a matèria primera en la producció d'aliments, els midons modificats han experimentat gran expansió en el desenvolupament de nombrosos productes a causa del seu caràcter versàtil. Les modificacions enzimàtiques es duen a terme per a realçar la funcionalitat del midó a fi d'esbiaixar les restriccions tecnològiques i millorar la qualitat del producte final. En concret, el midó de dacsa àmpliament produït i consumit, és apropiat com a ingredient principal en la producció d'aliments lliures de gluten. Aquesta Tesi aborda l'estudi de l'efecte individual de tres diferents enzims, alfa-amylasa fúngica, amiloglucosidasa i ciclodextrina glucosiltransferasa, sobre la temperatura de sub-gelatinizació del midó de dacsa. Es van realitzar diferents anàlisi per a ampliar el coneixement dels canvis estructurals i funcionals associats a l'acció de l'enzim. Així mateix, es va seleccionar el midó de dacsa modificat amb ciclodextrina glucosiltransferasa per a investigar la resposta glicémica en ratolins. L'índex glicémic es va relacionar amb l'absència/presencia de productes d'hidròlisis alliberats per l'acció catalítica de l'enzim i les propietats de gelatinización. Els midons de dacsa enzimàticament modificats van presentar alteracions funcionals en els grànuls de midó, la qual cosa els confereix característiques d'interès per a diversos usos alimentaris. / Durá De Miguel, Á. (2017). EFFECT OF ENZYMATIC TREATMENTS ON CARBOHYDRATE MATRICES TOWARDS HEALTHY GLUTEN FREE FOODS APPLICATION [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/79509 / TESIS
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Physical, functional and nutritional properties of flours from finger millet (Eleusine coracana) varieties fortified with vitamin B₂ and zinc oxideRamashia, Shonisani Eugenia 21 September 2018 (has links)
PhD (Food Science and Technology) / Department of Food Science and Technology / Finger millet (FM) (Eleusine coracana) grains are the staple food in Africa and India for communities with low socio-economic growth. The grains have high content of calcium, dietary fibre, carbohydrates that are rich in protein, fat, iron, phosphorus, vitamin and essential amino acids. Flours from milky cream (MC), brown and black varieties of FM were fortified with vitamin (vit) B₂ and zinc oxide (ZnO) in order to restore the nutrients that were lost during milling and sieving processes. The main aim of the study was to analyse the physical, nutritional composition and functional properties of flours from three (3) FM varieties fortified with vit B2 and ZnO. Pearl millet was used for comparison with the results obtained from this study. MC, brown and black varieties of FM flour treatments were arranged as a completely randomized design (CRD) in three (3) replicates. Physical properties: dimensional properties, colour attributes, kernel weight, bulk density (BD), true density, porosity, surface area, kernel volume, aspect ratio, sphericity and moisture content of the FM grains were analysed. Vitamins and minerals were also analysed. Functional properties: colour attributes, bulk density (BD), water absorption capacity (WAC), oil absorption capacity (OAC), swelling capacity (SC), swelling index (SI), foaming capacity (FC), foaming solubility (FS), dispersibility (Dis), viscosity (cool & hot paste), pasting properties, thermal properties and microscopic structure of FM flours were determined. Data generated were analysed using SPSS version 23.0. Moisture content of MC FM grain and flour was significantly higher (p < 0.05) than brown and black varieties but was within the specified range of <12%. This indicated the long storage shelf-life of the grains and flours. Length of brown FM grains was significantly higher (p < 0.05) when compared to MC and black varieties. MC variety was significantly higher than other varieties in width, kernel weight, bulk density, true density, aspect ratio and sphericity. The information obtained from this study will help in designing suitable equipment for planting, harvesting, storage, processing and packaging of grains. Pearl millet grain was significantly higher than FM flours in all physical properties. MC FM was significantly higher
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in L* (whiteness/ brightness), b* (yellowness/ blueness), C* (chroma), Hº (hue angle) and ZnO values compared to brown and black flours. MC raw fortified finger millet (RFFM) and instant fortified finger millet (IFFM) flours were significantly higher in vitamin B2. People prefer fortified MC flour because most of people living in South Africa use white maize as their staple food and it is similar to MC. Colour is the most important quality parameter in food processing industries and it is also attracts the consumer’s choice and preference. The vitamins and minerals that were lost during sieving, drying and milling were replaced by the two (2) fortificants added which may help to reduce the micronutrient deficiencies. Milky cream FM flours showed significantly high (p < 0.05) values in BD, WAC, OAC, SI, FC and dis. These are the fundamental physico-chemical properties that reflect the interaction between the composition and molecular structure. Length of brown FM grains was significantly higher (p < 0.05) when compared to MC and black variety. The MC variety was significantly higher than other varieties in width, kernel weight, bulk density, true density, aspect ratio and sphericity. Pearl millet was significantly higher than FM flours in all physical properties. MCFM variety was significantly higher in L* (whiteness/ brightness), b* (yellowness/ blueness), C* (chroma), and Hº (hue angle) values as compared to other FM varieties. Moisture content of MC flour was significantly higher as compared to brown and black FM flours. Pasting properties of MC raw finger millet (RFM) and RFFM flours showed significantly higher in peak viscosity (PV) (3518 cP), final viscosity (FV) (6554 cP), breakdown viscosity (BDV) (703 cP) and setback viscosity (SV) (3868 cP) as compared to other RFM and RFFM flours. Brown instant finger millet (IFM) and IFFM flours had significantly higher of PV (723 cP), trough viscosity (TV) (655 cP) and FV (983 cP). IFFM flours had significantly higher values of PV (712 cP), TV (614 cP) and FV (970 cP), respectively. The instant pearl millet (IPM) and instant fortified pearl millet (IFPM) showed significantly higher value in BDV (330 cP and 131 cP) and SV (362 cP and 346 cP), respectively. Thermal properties of black RFM was significantly higher in onset temperature (To) (74.31), peak temperature (TP) (81.94ºC) and conclusion temperature (Tc) (89.64) and RFFM starches were significantly high in To (81.80ºC), TP (84.22ºC) and TC (92.81ºC), respectively. Milky
ivcream IFM starch showed significantly higher values in TO (84.57ºC), TP (87.27ºC), Tc (92.81ºC) and ΔH (7.63ºC) compared to other starches. Brown IFFM flour was significantly higher value in To (85.88ºC) and TP (87.14ºC). The starch of IFPM was significantly higher in enthalpy of gelatinisation (6.91ºC) and PHI (2.94ºC) as compared to other FM starches. Brown IFM flour showed significantly higher value in gelatinisation temperature range (13.50ºC). The microscopic structure revealed that RFM and RFFM flours had oval and smooth surfaces. RFM and RFFM flours showed positive effect after fortificants were added because the starch granules, protein bodies and protein matrix were visible and formed crystal. IFM and IFFM flours had some holes, dents and rough surfaces. Instant fortified flours showed negative effect after fortificants were added due to technological processes such as recooking and remilling of flours. Different variations observed on physical, nutritional and functional properties after adding the fortificants may affect the physical, chemical and organoleptic properties of food produced from fortified flour. There is need to fortify FM flours with ZnO which may help to replace the value lost during milling and sieving operations. It is possible that the availability of ZnO could reduce the incidence of some non-communicable diseases. / NRF
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Plant Model Generator from Digital Twin for Purpose of Formal VerificationHåkansson, Johannes January 2021 (has links)
This master thesis will cover a way to automatically generate a formal model for plant verification from plant traces. The solution will be developed from trace data, stemming from a model of a digital twin of a physical plant. The final goal is to automatically generate a formal model of the plant that can be used for model checking for verifying the safety and functional properties of the actual plant. The solution for this specific setup will be generalized and a general approach for other systems will be discussed. Furthermore, state machine generation will be introduced. This includes generating state machine data from traces, and in the future is planned be used as an intermediate step between the trace data and model generation. The digital twin solution used in this project is a joint setup in Visual Components and nxtSTUDIO. The symbolic model checker NuSMV is utilized in order to verify the functional properties of the plant. / I detta examensarbete utforskas ett sätt att generera formella modeller av en process via inspelningar av dennes beteende. Lösningen är utvecklad från data över processens beteende, som tas upp av en digital tvilling. Det slutgiltliga målet är att med hjälp av den digitala tvillingen automatiskt generera en modell som kan användas för att verifiera säkerhet och funktioner för den riktiga processen. Lösningen blir sedan generaliserad för att i framtiden kunna bli applicerad på andra processer. Ett sätt att generera tillståndsmaskiner kommer läggas fram. Detta sätt kommer generera data för tillståndsmaskinerna genom den digitala tvillingens beteende och i framtiden planeras att användas som ett mellansteg för att generera de slutliga modellerna. Den digitala tvillingen som används i det här projektet är implementerat av Aalto universitet, och i flera program. Den visuella delen, som även spelar in tvillingens beteende, är implementerad i Visual Components. En kontroll för den digitala tvillingen är gjord i nxtSTUDIO. Verktyget för att verifiera modellens säkerhet och funktioner är gjord i NuSMV.
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Prostory amalgámů / Amalgam SpacesPeša, Dalimil January 2019 (has links)
In this thesis we introduce the concept of Wiener-Luxemburg amalgam spaces which are a modification of the more classical Wiener amalgam spaces intended to address some of the shortcomings the latter face in the context of rearrangement invariant Banach function spaces. We first provide some new results concerning quasinormed spaces. Then we illustrate the asserted shortcomings of Wiener amalgam spaces by provid- ing counterexamples to certain properties of Banach function spaces as well as rearrangement invariance. We introduce the Wiener-Luxemburg amalgam spaces and study their properties, including (but nor limited to) their normability, em- beddings between them and their associate spaces. Finally we provide some applications of this general theory. 1
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Gelatinization and Molecular Properties of Organic and Conventional Rice and Spelt StarchesIe, Pauline S. 26 September 2011 (has links)
No description available.
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Overview of tailoring cementitious composites with various nanomaterialsLi, L., Wang, X., Han, B., Ashour, Ashraf 02 November 2023 (has links)
No / Incorporating nanomaterials brings great changes in tailoring the nano-/micro-/macroscale structures of bulk cement paste phase and interfacial transition zone in the cementitious composites through the nano-core effect, thus achieving stronger, more durable, and smart/multi-functional cementitious composites. Owing to the nano-modification of cement paste in combination with the supplement of nanoscale continuity for multiscale raw materials of cementitious composites, nanomaterials gradually show the potential to become the indispensable seventh component of cementitious composites besides cement, water, fine aggregates, coarse aggregates, chemical additives, and mineral additives. Therefore tailoring cementitious composites with nanomaterials provides a promising approach to develop the new generation of cementitious composites (e.g., ultra-high performance, smart/multi-functional, and resilient) and sustainable infrastructures. This chapter aims to provide a systematic overview of tailoring cementitious composites with various types of nanomaterials. It initially covers the principle of tailoring cementitious composites with nanomaterials and dispersion of nanomaterials in cementitious composites. It then presents the properties of cementitious composites with 0D, 1D, and 2D nanomaterials, namely, hydration, rheology, workability, durability, functional, and mechanical properties. It also highlights various applications of cementitious composites with nanomaterials, including structural health monitoring, traffic detection, and pollutant purification. This chapter concludes by presenting the future prospects of cementitious composites with nanomaterials.
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Caractérisation multi-niveau de protéines laitières : influence de l'environnement ionique et de la température / Multilevel Characterization of Milk Proteins : Influence of Ionic Environment & TemperatureHussain, Raza 06 June 2012 (has links)
Le but de cette thèse était d'étudier et de mieux comprendre les mécanismes d'interaction entre protéines laitières (caséines micellaires natives NMC et protéines de lactosérum natives WPI) sous forme de poudres dispersées (5% p/v) dans des milieux fortement ionisés par des sels (NaCl, CaCl2). D'une manière générale notre étude a été organisée en trois parties. Premièrement, nous avons étudié l'influence des milieux ioniques (eau distillé, solution de NaCl, solution de CaCl2) sur la réhydratation de protéines laitières. Dans une seconde partie nous avons caractérisé les dispersions en milieux ionisés par les études respectives de la structure secondaire des protéines, de la taille et de la morphologie des particules en cours de dispersion et de l'hydrophobicité des protéines. Dans la troisième et dernière partie nous nous sommes intéressés aux propriétés fonctionnelles des protéines du lactosérum par l'effet combiné de la température (30 - 90°C) et de la concentration en NaCl (0,75 - 3%). La réhydratation des protéines du lait a montré deux comportements distincts en fonction du type de sel d'une part (NaCl, CaCl2) et de la concentration d'autre part (0 - 12%). Dans les dispersions de NMC, avec l'ajout et l'augmentation de la concentration de NaCl on observe (DLS, TEM), une désintégration des micelles de taille 150 nm en petites micelles de 20-30 nm qui sont plus ou moins agrégées. En définitive, les propriétés fonctionnelles des protéines du WPI dépendent en même temps de la concentration en sel et de la température appliquée / The overall objective of this work was to investigate the mechanisms of protein-salt interactions and linkage between milk proteins powders and milk proteins dispersions (5% w/v) mainly NMC and WPI under various ranges of ionic environments (distilled water, NaCl solution and CaCl2 solution. In the first phase, we investigated the influence of the ionic environments on milk proteins powders rehydration profiles. The second phase of this study includes the characterization of milk proteins dispersions in an aqueous ionic environment regarding changes in the protein: secondary structure (ß-sheet, alpha-helix, ß-turns and unordered structures), size, morphological features and surface hydrophobicity by using FTIR, TEM, and DLS with other complimentary techniques. In the last part, the functionality of whey proteins was studied by the combined effect of heat and different ratios of salts. For this purpose, the study was exclusively focalized in an aqueous ionic medium composed of NaCl (0.75-3%) at different temperatures (30-90°C). The results obtained from the first part showed two distinct rehydration behaviors depending on the salts type and concentration. For the NMC dispersions under salt increase, spherical micelles with an average size around 150 nm disintegrated in sub-micelles around 20-30 nm and more or less aggregated were observed by DLS and TEM. WPI dispersions in water were composed of well separated proteins by a spherical shape with two populations around 6 and 70 nm. Salt increase resulted in an aggregation of the proteins and the formation of denser aggregates. Moreover, a combined salt/heat resulted showed a stabilizing effect on the secondary structural elements of both Amide I and III bands and higher denaturation temperatures observed by FTIR and µDSC respectively. A size and morphological investigation showed a transition from spherical/compact protein aggregates to linear ones. Finally, this work demonstrated that whey protein functional properties depend on both salt and how heat treatment is applied
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Etude des propriétés fonctionnelles de la glycoprotéine d'enveloppe des variants transmis du VIH-1 et de leur évolution à l'échelle individuelle et populationnelle / Functional properties of envelope glycoproteins of transmitted HIV-1 variants and their evolution during the infection or over the course of the epidemicBeretta, Maxime 18 October 2018 (has links)
Lors de la transmission sexuelle du VIH-1, un seul ou un nombre très limité de variants viraux sont transmis parmi ceux présents chez le donneur. Il est important de comprendre si le variant transmis est sélectionné aléatoirement parmi ceux présents chez le donneur ou s’il possède un avantage sélectif qui le prédispose à établir plus efficacement une nouvelle infection. Lors de nos différents travaux, nous avons pu observer chez quatre patients une évolution parallèle des propriétés génétiques, antigéniques et fonctionnelles de la glycoprotéine d’enveloppe au cours de l’infection. L’évolution de certaines propriétés est répercutée à l’échelle populationnelle. Néanmoins nous avons montré que malgré ces évolutions, les virus transmis au sein d’une même chaîne de transmission présentent des propriétés biologiques conservées. L’ensemble de nos résultats vont en faveur d’une sélection d’un variant viral avec des propriétés particulières lors de la transmission. De plus le variant transmis possède une région V3 particulièrement conservée associée à un tropisme CCR5, une sensibilité au Maraviroc et semble avoir besoin d’un taux élevé de CD4 à la surface de la cellule cible. / During HIV-1 sexual transmission, a single virus among the numerous viral variants present in the donor is transmitted most often. The key question is to understand if transmitted variants are randomly selected among variants from the donor or they have biological properties that predispose them to establish more efficiently a new infection. We observed a parallel evolution of genetic, antigenic and functional properties of the envelope glycoprotein in four patients during the infection. In addition, the evolution of some properties is also observed at the populational level. However, we showed that transmitted variants from a same transmission chain share similar biological properties. Together our results suggest that the transmission bottleneck is mainly non-stochastic and involves the selection viral variants harboring specific phenotypic properties. Despite transmitted variants have a conserved V3 region associated with a CCR5 tropism, sensitivity to Maraviroc and seem to require high level of CD4 to efficiently infect target cells.
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Efeito da extrusão termoplástica nas características físico-químicas e nutricionais do rúmen bovino e sua aplicação na alimentação humana / Thermoplastic extrusion effects on physical-chemical and nutritional properties of bovine rumen and its application in human feed.Silva, Ana Carolina Conti e 22 February 2008 (has links)
Introdução. O rúmen bovino constitui um subproduto de abatedouro por ser rejeitado sensorialmente e culturalmente. Apesar disso, representa uma ótima fonte protéica, sendo desejável seu aproveitamento integral na alimentação humana. Objetivo geral. Desenvolver um produto à base de rúmen bovino, avaliando suas características físico-químicas e nutritivas e sua aplicação em alimentos. Metodologia. O rúmen bovino foi desengordurado a frio e extrusado em extrusora de rosca única. Utilizou-se a Metodologia de Superfície de Resposta para verificação dos efeitos da extrusão sobre as propriedades funcionais do rúmen: capacidade de retenção de água, capacidade de emulsificação, estabilidade da emulsão, solubilidade da proteína e hidrofobicidade da superfície protéica. Foi avaliada a composição nutritiva do rúmen (composição centesimal, colesterol, perfil de ácidos graxos e sua qualidade protéica através da composição de aminoácidos e digestibilidade real em ratos). Três produtos cárneos (lingüiça toscana, hambúrguer de frango e quibe) foram fabricados com extrusado ou com farinha de rúmen, analisados sensorialmente e comparados com produtos cárneos contendo extrusado de concentrado protéico de soja. Resultados. A capacidade de emulsificação, a solubilidade protéica e a hidrofobicidade da superfície protéica aumentaram após a extrusão, sendo que a capacidade de retenção de água e a estabilidade da emulsão foram reduzidas. A umidade mostrou ter influência sobre a variável resposta capacidade de retenção de água. As condições testadas de extrusão do rúmen foram fixadas em 35% de umidade (base seca) e 150ºC de temperatura de processamento. A avaliação da composição centesimal mostrou que o rúmen é uma excelente fonte protéica, seu colesterol foi reduzido consideravelmente após o desengorduramento e os ácidos graxos saturados foram extraídos totalmente. O escore de aminoácidos corrigido pela digestibilidade real da proteína foi de 1 ou 100% antes e após a extrusão. As análises sensoriais mostraram que para a lingüiça, a adição de rúmen deve ser feita em sua forma extrusada, sendo que no hambúrguer de frango e no quibe, a utilização de extrusado ou farinha de rúmen resultou em igual aceitação sensorial. Conclusão. A extrusão constitui uma forma de aproveitamento do rúmen bovino, mas não é essencial para sua aplicação em alimentos, já que dependendo do produto não se mostrou necessária. Por outro lado, a extrusão provocou mudanças nas propriedades funcionais do rúmen, favorecendo sua aplicação em determinados produtos embutidos e melhorando a aceitação sensorial. A qualidade nutritiva da proteína tanto da farinha como do extrusado foi alta e não foi afetada pela extrusão. / Introduction. Bovine rumen is a slaughterhouse by-product rejected by sensorial and cultural reasons. Nevertheless, it is a great proteic source and its utilization in human feed is necessary. Objective. Development of a product made with bovine rumen, analyzing its physical-chemical and nutritive characteristics and its use in human feed. Methodology. Bovine rumen was deffated and extruded in a single screw extruder. The Response Surface Methodology was applied to verify extrusion effects on functional properties of rumen: water holding capacity, emulsifying capacity, emulsion stability, protein solubility and surface hydrophobicity of protein. The nutritive composition of rumen (composition per 100g, cholesterol and fatty acid profile) was evaluated and also its proteic quality through its amino acid composition and in vivo true digestibility. Three meat products (sausage, chicken hamburger and quibe) were produced with extruded or flour rumen and compared with extruded of soy protein concentrated through sensory analysis. Results. After extrusion, emulsifying capacity, protein solubility and surface hydrophobicity of protein were improved, while water holding capacity and emulsion stability were reduced. Moisture had influence on water holding capacity. Extrusion of bovine rumen was fixed at 35% of moisture (dry basis) and 150oC of processing temperature. The evaluation of composition per 100g showed that bovine rumen is a great proteic source. After deffating, cholesterol was reduced and saturated fatty acids were totally removed. Amino acid scores corrected by true protein digestibility were 1 or 100% before and after extrusion. Sensory analysis showed that extruded bovine rumen should be added at sausage instead of flour rumen, but both extruded or flour rumen can be added at chicken hamburger and at quibe with equal sensory acceptance. Conclusion. Extrusion is a way of bovine rumen utilization, but it is not essential for its use in food, since it was not necessary in some cases. Nevertheless, extrusion changed functional properties of rumen, favoring its application in some sausage products and improving its sensory acceptance. Nutritive quality of protein, both raw and extruded rumen, was high and it was not affected by extrusion.
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Efeito da extrusão termoplástica nas características físico-químicas e nutricionais do rúmen bovino e sua aplicação na alimentação humana / Thermoplastic extrusion effects on physical-chemical and nutritional properties of bovine rumen and its application in human feed.Ana Carolina Conti e Silva 22 February 2008 (has links)
Introdução. O rúmen bovino constitui um subproduto de abatedouro por ser rejeitado sensorialmente e culturalmente. Apesar disso, representa uma ótima fonte protéica, sendo desejável seu aproveitamento integral na alimentação humana. Objetivo geral. Desenvolver um produto à base de rúmen bovino, avaliando suas características físico-químicas e nutritivas e sua aplicação em alimentos. Metodologia. O rúmen bovino foi desengordurado a frio e extrusado em extrusora de rosca única. Utilizou-se a Metodologia de Superfície de Resposta para verificação dos efeitos da extrusão sobre as propriedades funcionais do rúmen: capacidade de retenção de água, capacidade de emulsificação, estabilidade da emulsão, solubilidade da proteína e hidrofobicidade da superfície protéica. Foi avaliada a composição nutritiva do rúmen (composição centesimal, colesterol, perfil de ácidos graxos e sua qualidade protéica através da composição de aminoácidos e digestibilidade real em ratos). Três produtos cárneos (lingüiça toscana, hambúrguer de frango e quibe) foram fabricados com extrusado ou com farinha de rúmen, analisados sensorialmente e comparados com produtos cárneos contendo extrusado de concentrado protéico de soja. Resultados. A capacidade de emulsificação, a solubilidade protéica e a hidrofobicidade da superfície protéica aumentaram após a extrusão, sendo que a capacidade de retenção de água e a estabilidade da emulsão foram reduzidas. A umidade mostrou ter influência sobre a variável resposta capacidade de retenção de água. As condições testadas de extrusão do rúmen foram fixadas em 35% de umidade (base seca) e 150ºC de temperatura de processamento. A avaliação da composição centesimal mostrou que o rúmen é uma excelente fonte protéica, seu colesterol foi reduzido consideravelmente após o desengorduramento e os ácidos graxos saturados foram extraídos totalmente. O escore de aminoácidos corrigido pela digestibilidade real da proteína foi de 1 ou 100% antes e após a extrusão. As análises sensoriais mostraram que para a lingüiça, a adição de rúmen deve ser feita em sua forma extrusada, sendo que no hambúrguer de frango e no quibe, a utilização de extrusado ou farinha de rúmen resultou em igual aceitação sensorial. Conclusão. A extrusão constitui uma forma de aproveitamento do rúmen bovino, mas não é essencial para sua aplicação em alimentos, já que dependendo do produto não se mostrou necessária. Por outro lado, a extrusão provocou mudanças nas propriedades funcionais do rúmen, favorecendo sua aplicação em determinados produtos embutidos e melhorando a aceitação sensorial. A qualidade nutritiva da proteína tanto da farinha como do extrusado foi alta e não foi afetada pela extrusão. / Introduction. Bovine rumen is a slaughterhouse by-product rejected by sensorial and cultural reasons. Nevertheless, it is a great proteic source and its utilization in human feed is necessary. Objective. Development of a product made with bovine rumen, analyzing its physical-chemical and nutritive characteristics and its use in human feed. Methodology. Bovine rumen was deffated and extruded in a single screw extruder. The Response Surface Methodology was applied to verify extrusion effects on functional properties of rumen: water holding capacity, emulsifying capacity, emulsion stability, protein solubility and surface hydrophobicity of protein. The nutritive composition of rumen (composition per 100g, cholesterol and fatty acid profile) was evaluated and also its proteic quality through its amino acid composition and in vivo true digestibility. Three meat products (sausage, chicken hamburger and quibe) were produced with extruded or flour rumen and compared with extruded of soy protein concentrated through sensory analysis. Results. After extrusion, emulsifying capacity, protein solubility and surface hydrophobicity of protein were improved, while water holding capacity and emulsion stability were reduced. Moisture had influence on water holding capacity. Extrusion of bovine rumen was fixed at 35% of moisture (dry basis) and 150oC of processing temperature. The evaluation of composition per 100g showed that bovine rumen is a great proteic source. After deffating, cholesterol was reduced and saturated fatty acids were totally removed. Amino acid scores corrected by true protein digestibility were 1 or 100% before and after extrusion. Sensory analysis showed that extruded bovine rumen should be added at sausage instead of flour rumen, but both extruded or flour rumen can be added at chicken hamburger and at quibe with equal sensory acceptance. Conclusion. Extrusion is a way of bovine rumen utilization, but it is not essential for its use in food, since it was not necessary in some cases. Nevertheless, extrusion changed functional properties of rumen, favoring its application in some sausage products and improving its sensory acceptance. Nutritive quality of protein, both raw and extruded rumen, was high and it was not affected by extrusion.
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