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SUPLEMENTAÇÃO DE TAURINA EM DIETAS PARA JUNDIÁ (Rhamdia quelen) / TAURINE SUPPLEMENTATION IN DIETS FOR JUNDIÁ (Rhamdia quelen)Martinelli, Suziane Ghedini 26 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Taurine is an essential amino acid in several physiological processes in the animal body. Its biosynthesis, from methionine and cystine, differs among the different species of fish and is also affected by their presence or not in the ingredients used in the manufacture of animal feed, so supplementation can improve feed efficiency and protect cells against oxidative damage of reactive oxygen species. The objective of this study was to evaluate the supplementation of taurine on performance, metabolic and antioxidant potential parameters in silver catfish (Rhamdia quelen). Three experiments were conducted on UFSM Fish Farming Laboratory: the first two, lasting 54 days, evaluated the productive performance and metabolic parameters of silver catfish (5g) fed with diet based on plant ingredients or fish meal as a source of protein, both being supplemented with taurine (0, 0.5, 1.5 or 2%). In these experiments, the design was completely randomized, with four levels of supplementation with four replications. In the third experiment, which lasted 24 days, it was evaluated the antioxidant potential of taurine in silver catfish (7g) when supplemented with methionine in semipurified diet. In the latter, the design was completely randomized in a factorial 3x4 (three levels of methionine and four taurine). The results obtained in the experiment with the addition of taurine in the diet with fish meal as protein source indicate that supplementation with this amino acid did not improve the growth of the animals compared to the unsupplemented diet. It was also observed that a higher level of taurine (2%) showed a decrease in growth, rates of protein deposition and consumption, and an increase in feed conversion. For the animals fed with plant diets there was no effect of taurine on growth and consumption. However, the addition of 0.5% taurine in the diet yielded higher protein retention, lower catabolism and better feed conversion, compared to treatment with 2% taurine. Metabolic parameters of the animals in both experiments were not affected by medium supplementation representative of taurine in the diet. In the third experiment, the evaluation of the antioxidant taurine and methionine action showed that with level of 1.5 and 2% taurine and 3.5% methionine had lower protein carbonyl formation and increased activity of antioxidant enzyme superoxide dismutase and decreased protein catabolism. Both growth studies showed that juvenile silver catfish did not require taurine supplementation even when fed with diets containing vegetable sources such as protein-based, though the third experiment showed that taurine has antioxidant action, with respect to the methionine level used. / A taurina é um aminoácido fundamental em vários processos fisiológicos no organismo animal. Sua biossíntese, a partir da metionina e cistina, difere entre as diversas espécies de peixes e também é afetada pela sua presença ou não nos ingredientes utilizados na confecção das rações, de modo que sua suplementação pode melhorar a eficiência alimentar e proteger as células contra os danos oxidativos das espécies reativas de oxigênio. Assim, o objetivo desse trabalho foi avaliar a suplementação de taurina sobre parâmetros zootécnicos, metabólicos e potencial antioxidante em jundiás (Rhamdia quelen). Foram conduzidos três experimentos no Laboratório de Piscicultura da UFSM: nos dois primeiros, com duração de 54 dias, avaliaram-se o desempenho produtivo e parâmetros metabólicos de jundiás (5g) alimentados com dieta à base de ingredientes vegetais ou com farinha de peixe como fonte proteica, sendo ambas suplementadas com taurina (0, 0,5, 1,5 ou 2%). Nestes experimentos, o delineamento foi o inteiramente casualizado, sendo quatro níveis de suplementação com quatro repetições. No terceiro, com duração de 24 dias, avaliou-se o potencial antioxidante da taurina em jundiás (7g) quando suplementada juntamente com a metionina em dieta semipurificada. Neste último, o delineamento utilizado foi o inteiramente casualizado em esquema fatorial 3×4 (três níveis de metionina e quatro de taurina). Os resultados obtidos no experimento com adição de taurina em dietas com farinha de peixe como fonte protéica indicaram que a suplementação com esse aminoácido não melhorou o crescimento dos animais em relação à dieta não suplementada. Foi observado ainda que no nível mais elevado de taurina (2%) houve diminuição no crescimento, nos índices de deposição proteica e no consumo, além de aumentar a conversão alimentar aparente. Para os animais alimentados com as dietas vegetais não se verificou efeito da taurina no crescimento e no consumo. Entretanto, a adição de 0,5% de taurina nas dietas proporcionou maior retenção protéica, menor catabolismo e melhor conversão alimentar, comparado ao tratamento com de 2% de taurina. Os parâmetros metabólicos dos animais, de ambos os experimentos, não foram afetados de forma representativa pela suplementação de taurina nas dietas. No terceiro experimento, de avaliação da ação antioxidante da taurina e da metionina, foi observado que com nível de 1,5 e 2% de taurina e 3,5% de metionina houve menor formação de proteína carbonil e aumento na atividade da enzima antioxidante superóxido dismutase, além de menor catabolismo protéico. Os dois estudos de crescimento mostraram que os juvenis de jundiá não necessitam de suplementação de taurina, mesmo quando alimentados com dietas contendo fontes vegetais como base protéica, entretanto o terceiro experimento mostrou que a taurina apresenta ação antioxidante, tendo relação com o nível de metionina utilizado.
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RECOVERY OF PROTEIN AND ORGANIC COMPOUNDS FROM SECONDARY-FERMENTED THIN STILLAGE2016 February 1900 (has links)
Wheat-based thin stillage (W-TS) is liquid by-product of wheat ethanol production and contains valuable chemical intermediates such as 1,3-propanediol (1,3-PD), acetic acid, and glycerophosphorylcholine. Unfortunately, these compounds cannot be recovered/extracted easily due to the presence of high boiling point and hygroscopic solutes and unfermented particles from ethanol fermentation. Fermentation improvement study using endemic bacteria augmented with Lactobacillus panis PM1B discovered that glucose, incubation temperature, micronutrients, and pH adjustment affected two-stage fermentation (TSF). Importantly, fermentation could be scaled to a 210 L fermenter where 2% (w/v) 1,3-PD was produced. Unfermented particles should be removed prior to compound recovery. TSF was effective in producing solutions that were virtually free of colloids. Bacteria present in TSF system produced anoxic gas and exopolysaccharides and the combined action produced substantially clear solution. On the other hand, recovered particles, rich in lactobacilli, had a high protein content (50%, w/w, dry basis), which might be useful as an animal feed ingredient. Washing processes could lower moisture content and recover a high protein slurry (60% w/w, dry basis). Practical processes that incorporated fermentation using Lactobacilli could add substantial value to thin stillage and increase the value of products from ethanol production. These processes are scalable and readily implemented.
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Is the inclusion of animal source foods in fortified blended food justified?Noriega, Kristen January 1900 (has links)
Master of Science / Department of Human Nutrition / Brian Lindshield / Fortified blended foods (FBF) are used for the prevention and treatment of moderate acute malnutrition (MAM) in nutritionally vulnerable individuals, particularly children. A recent review of current FBF recommended the addition of animal source food (ASF), in the form of whey protein concentrate (WPC), to FBF, especially corn soy blend. The justifications for this recommendation include the potential of ASF to increase length, weight, muscle mass accretion, and recovery from wasting, as well as improve the product protein quality and provide essential growth factors. Evidence was collected from the following four different types of studies: 1) epidemiological, 2) ASF versus no intervention or a low-calorie control, 3) ASF versus an isocaloric non-ASF, and 4) ASF versus an isocaloric, isonitrogenous non-ASF. Epidemiological studies consistently associated improved growth outcomes with ASF consumption; however, little evidence from isocaloric and isocaloric, isonitrogenous interventions was found to support the inclusion of meat or milk in FBF. Evidence suggests that whey may benefit muscle mass accretion, but not linear growth. Overall, there is little evidence to support the costly addition of WPC to FBFs. Further randomized isocaloric, isonitrogenous ASF interventions with nutritionally vulnerable children are needed.
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Recovery of Recombinant and Native Proteins from Rice and Corn SeedWilken, Lisa Rachelle 2009 August 1900 (has links)
Plants are potential sources of valuable recombinant and native proteins that can
be purified for pharmaceutical, nutraceutical, and food applications. Transgenic rice and
corn germ were evaluated for the production of novel protein products. This dissertation
addresses: 1) the extraction and purification of the recombinant protein, human
lysozyme (HuLZ), from transgenic rice and 2) the processing of dry-milled corn germ
for the production of high protein germ and corn protein concentrate (CPC).
The factors affecting the extraction and purification of HuLZ from rice were
evaluated. Ionic strength and pH was used to optimize HuLZ extraction and cation
exchange purification. The selected conditions, pH 4.5 with 50 mM NaCl, were a
compromise between HuLZ extractability and binding capacity, resulting in 90% purity.
Process simulation was used to assess the HuLZ purification efficiency and showed that
the processing costs were comparable to native lysozyme purification from egg-white,
the current predominant lysozyme source.
Higher purity HuLZ (95%) could be achieved using pH 4.5 extraction followed
by pH 6 adsorption, but the binding capacity was unexpectedly reduced by 80%. The
rice impurity, phytic acid, was identified as the potential cause of the unacceptably low capacity. Enzymatic (phytase) treatment prior to adsorption improved purification,
implicating phytic acid as the primary culprit. Two processing methods were proposed
to reduce this interference: 1) pH 10 extraction followed by pH 4.5 precipitation and pH
6 adsorption and 2) pH 4.5 extraction and pH 6 adsorption in the presence of TRIS
counter-ions. Both methods improved the binding capacity from 8.6 mg/mL to >25
mg/mL and maintained HuLZ purity.
Processing of dry-milled corn germ to increase protein and oil content was
evaluated using germ wet milling. In this novel method, dry-milled germ is soaked and
wet processed to produce higher value protein products. Lab-scale and pilot-scale
experiments identified soaking conditions that reduced germ starch content, enhanced
protein and oil content, and maintained germ PDI (protein dispersibility index). Soaking
at neutral pH and 25 degrees C maintained germ PDI and improved CPC yield from defatted
germ flour. CPC with greater than 75% protein purity was produced using protein precipitation or
membrane filtration.
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Studies on heat- and pressure-induced interactions of milk proteins : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New ZealandPatel, Hasmukh Ambalal January 2007 (has links)
The present study was aimed at understanding the high pressure (HP) processing-induced interactions of milk proteins in whey protein concentrate (WPC) solutions, in skim milk and in pure protein systems. The changes in milk proteins induced by heat treatments in the same systems under selected conditions were also evaluated. The main approach taken was to elucidate changes in the whey proteins in heat- and pressure-treated samples from common aliquots, under identical conditions, using various one-dimensional (1D) and two-dimensional (2D) polyacrylamide gel electrophoresis (PAGE) techniques in the absence or presence of a disulphide bond reducing agent. In some instances, the samples were also analysed using small deformation rheology, size exclusion chromatography (SEC) and transmission electron microscopy (TEM). The results of the present study indicated that, in general terms, heat treatment and HP treatment had common effects, i.e. denaturation and subsequent aggregation of whey proteins. Both heat treatment and HP treatment generated disulphide-bonded and hydrophobically bonded aggregates of whey proteins. However, the sensitivities of each of the whey proteins to heat treatment [immunoglobulin (Ig) > lactoferrin (LF) > bovine serum albumin (BSA) > β-laetoglobulin B (β-LG B) > β-LG A > α-lactalbumin (α-LA)] and pressure treatment (β-LG B > β-LG A > IgG > LF > BSA > α-LA) were considerably different. Also, HP treatment generated a comparatively greater proportion of smaller aggregates than did heat treatment. The effects of protein concentration, intensity of pressure treatment, holding time and pressurising temperature on whey protein aggregation in WPC solutions were investigated. The rate of aggregation of whey proteins increased with an increase in the concentration of protein in the WPC solution and the pressurising temperature. The combination of low protein concentration, mild pressure treatment (200 MPa) and low pressurising temperature (20°C) led to minimal loss of native-like and SDS-monomeric β-LG, whereas the combination of high protein concentration, severe pressure treatment (600 MPa) and higher pressuring temperature (40°C and higher) led to significant loss of both native-like and SDS-monomeric β-LG. The sensitivity of pressure-resistant whey proteins, such as α-LA and BSA, to the aggregation was significantly increased at pressurising temperatures of 40°C and higher. Self-supporting gels were formed when 8 or 12% (w/v) WPC solutions were pressure treated at 600-800 MPa. 20°C. Detailed analysis of the behaviour of the proteins during the formation of these gels revealed a novel pathway, suggesting that intermolecular disulphide bond formation occurred at high pressure but that hydrophobic association became important after the HP treatment. In the later part of the study, heat- and HP-induced interactions of caseins and whey proteins were studied in a more complex system, i.e. skim milk. With the application of modified PAGE techniques, it was possible to show that the high molecular weight disulphide-bonded aggregates that were formed by HP treatment of skim milk contained disulphide-linked complexes consisting of αS2-casein (αS2-CN) as well as κ-CN, β-LG and other whey proteins. The results showed that the effects of heat treatment and HP on the interactions of the caseins and whey proteins in milk were significantly different. The accessibility of αS2-CN and the formation of complexes involving αS2-CN, κ-CN and whey proteins in the HP-treated milk, as demonstrated using the modified 2D PAGE technique, and as explained by possible proposed reactions of the caseins and whey proteins in pressure-treated milk, was an important finding of the present study. Finally, a study on the effects of HP treatment in model systems using pure proteins in solution, both singly or in binary and ternary combinations, generated very useful information and clarified the role of each protein in pressure-induced aggregation and interactions of milk proteins in complex systems such as WPC and milk. It was found that the reactions of β-LG were not significantly affected by other proteins such as α-LA or BSA, but that the presence of β-LG in the system catalysed the reactions of other proteins such as α-LA or BSA.
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Desenvolvimento de espessante alimentar para líquidos com valor nutricional agregado, destinados a indivíduos disfágicos / Development of food thickner for liquids with aggregated nutritional value intended for dysphagic individualsPagno, Carlos Henrique January 2009 (has links)
A deglutição é um processo coordenado e extremamente complexo, envolvendo contração e inibição de músculos localizados entre a boca e o estômago. Alterações neste sistema podem gerar disfagia, sinal comum de diversas doenças orgânicas, alterações neurológicas ou doenças neuromusculares, produzindo no paciente dificuldade na mastigação e deglutição de alimentos. Prover deglutição segura para indivíduos disfágicos é um desafio, contudo, esta pode ser facilitada se os alimentos tiverem a textura modificada e os líquidos forem espessados. Dessa maneira, este trabalho teve por objetivo desenvolver uma formulação de espessante alimentar, com valor nutricional agregado, para espessar diferentes líquidos, tornando-os com consistência adequada para pacientes disfásicos e avaliar sua ação em diferentes líquidos, testando a influência do tempo de espessamento e temperatura, sobre a estabilidade das viscosidades obtidas com as amostras. O ingrediente base usado para formulação e fonte de proteína foi o concentrado protéico de soro de leite (WPC), obtido experimentalmente, através da utilização das tecnologias de membranas, ultrafiltração (UF) e diafiltração (DF), através de três experimentos distintos. Inicialmente, 30 litros de soro em pó reconstituído, foram concentrados através da ultrafiltração, com redução do volume para cinco litros, a partir deste volume realizaram-se as diafiltrações. No primeiro experimento executaram-se quatro DF, duas de cinco litros e duas de 2,5 litros, obtendo-se WPC-1 com 56% de proteína. No segundo experimento também com quatro DF, executaram-se dois deles com 10 litros e dois com cinco litros, obtendo-se o WPC-2, com 71% de proteína. Para o terceiro experimento, os ciclos das diafiltrações foram aumentados para seis DF de cinco litros cada, obtendo-se o WPC-3, com 80% de proteína. Os concentrados obtidos foram liofilizados e caracterizados em relação a suas propriedades funcionais, sendo a solubilidade a mais importante por estar diretamente ligada à utilização em formulações alimentares de bebidas. Obteve-se solubilidade média de 70, 77 e 85% para WPC-1, 2 e 3 respectivamente. Pelas características obtidas de concentração de proteínas e percentual de solubilidade, o concentrado protéico obtido no terceiro experimento foi o selecionado para ser utilizado na formulação. Esta ficou constituída de 68% de concentrado protéico de soro de leite, 2% de mix de vitaminas e minerais e 30% do agente espessante (goma guar). Através de testes preliminares realizados com o agente espessante, determinou-se a porção do produto formulado necessária de ser adicionada aos líquidos para que os mesmos atingissem os níveis de consistência desejados, ou seja, 4,2 g para consistência de néctar (50 – 351 cP), 6,7 g para consistência de mel (351-1750 cP) e 9,2 g para consistência de pudim (> 1750 cP), tradicionalmente recomendadas para indivíduos disfásicos, segundo o National Dysphagia Diet Guidelines (NDD). Diferentes amostras (leite, sucos de abacaxi, de uva e de laranja) foram espessadas e realizadas medidas da viscosidade aparente, expressas em centipoise (cP), nos tempos pós-preparo: 10 minutos, 2 horas com taxa de cisalhamento (“shear rate”) de 50s-1 a 25ºC. As amostras foram armazenadas sob refrigeração e após 24 horas, novas medidas foram realizadas com taxa de cisalhamento de 50s-1 a 10ºC. Houve diferença estatística significativa entre as médias de viscosidade nos tempos de preparo de todos os níveis de consistência, demonstrando que o agente espessante utilizado continuou agindo, hidratando-se e aumentando a viscosidade com o passar do tempo. Também foi encontrada diferença significativa entre algumas amostras, com diferentes líquidos de diluição, quando comparadas entre si no mesmo nível de consistência. No entanto, as amostras apresentaram viscosidade dentro dos níveis sugeridos pela National Disfagic Diet, com exceção da consistência de pudim que, no tempo 10 minutos, permaneceu abaixo dos limites, adequando-se com o tempo, para o consumo de indivíduos disfágicos. / The swallowing is a coordinated and extremely complex process, involving contractions and inhibitions of muscles located between the mouth and the stomach. Alterations on this system can generate dysphagia, common sign of several organic diseases, neurological alterations or neuromuscular diseases, producing in the patient difficulty in the mastication and Swallowing of food .To provide safe swallowing for dysphagic individuals is a challenge, however, this can be facilitated, if the food has modified texture and if the liquids are thickened. In this way, the purpose of this work was to develop a formulation of food thickener, with aggregated nutritional value, to thicken different liquid foods, giving them an appropriate consistence for dysphagic individuals and to evaluate its action in different liquid foods, testing the influence of the time of thickening and temperature, over the stability of the viscosities obtained by the samples. As ingredient base for formulation and protein source was used whey protein concentrate (WPC), obtained experimentally, through the use of the technologies of membranes, the ultrafiltration (UF) and diafiltration (DF), through three different experiments. Initially, 30 liters of reconstituted powder serum, were concentrate through ultrafiltration, with reduction of the volume for cinco liters, starting from this volume the diafiltration took place. In the first experiment quatro DF were executed, two of cinco liters and two of 2.5 liters, obtained WPC-1 with 56% of protein. In the second experiment quatro DF were executed, two of them with 10 liters and two with cinco liters, obtaining WPC-2 with 71% of protein. For the third experiment, the cycles of the diafiltration were increased for 6 DF of 5 liters each, obtaining WPC-3 with 80% of protein.The obtained concentrates were liofilized and characterized in relation to its functional properties, being the solubility the most important for being directly linked to the use in alimentary formulations and drink. Average solubility of 70, 77 and 85% were obtained for WPC, 1, 2 and 3 respectively. Due to the obtained characteristics of protein concentrate and its solubility, the WPC obtained in the third experiment was selected for if used in the formulation. This was constituted of 68% of whey protein concentrate, 2% of mix of Vitamins and Minerals and 30% of the thickning agent (gum guar). Through preliminary tests accomplished with the thickening agent the amount of formulated product necessary to reach the desired consistence levels was determined, being 4.2 g for nectar consistence (50 – 351 cP), 6.7 g for honey consistence (351-1750 cP) and 9.2 g for pudding (> 1750 cP), traditionally recommended for dysphagic individuals according to National Dysphagia Diet Guidelines (NDD). Different samples (milk, pineapple juices, and grape and orange) were thickened and measurements of apparent viscosity were carried out, expressed in centipoise (cP), in the times after preparation: 10 minutes, 2 hour with shear rate of 50s-1 to 25±2ºC. The samples were stored under refrigeration and after 24 hours, new measurements were accomplished with shear rate of 50 s-1 to 10±2ºC. There were significant statistic difference among the average viscosity in the times of preparation of all the consistence levels, demonstrating that the thickening agent used continued acting, increasing the viscosity in the course of time. As well as significant differences among some samples when compared to each other in the same consistence level, caused by the different constituents of the drinks taken as sample. However, all samples presented viscosity inside the levels suggested by National Dysphagic Diet, except for the pudding consistence that, in the time of 10 minutes, was below these limits, fitting with time, being for this inside the levels suggested, appropriated for consumption by dysphagic individuals.
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Desenvolvimento de espessante alimentar para líquidos com valor nutricional agregado, destinados a indivíduos disfágicos / Development of food thickner for liquids with aggregated nutritional value intended for dysphagic individualsPagno, Carlos Henrique January 2009 (has links)
A deglutição é um processo coordenado e extremamente complexo, envolvendo contração e inibição de músculos localizados entre a boca e o estômago. Alterações neste sistema podem gerar disfagia, sinal comum de diversas doenças orgânicas, alterações neurológicas ou doenças neuromusculares, produzindo no paciente dificuldade na mastigação e deglutição de alimentos. Prover deglutição segura para indivíduos disfágicos é um desafio, contudo, esta pode ser facilitada se os alimentos tiverem a textura modificada e os líquidos forem espessados. Dessa maneira, este trabalho teve por objetivo desenvolver uma formulação de espessante alimentar, com valor nutricional agregado, para espessar diferentes líquidos, tornando-os com consistência adequada para pacientes disfásicos e avaliar sua ação em diferentes líquidos, testando a influência do tempo de espessamento e temperatura, sobre a estabilidade das viscosidades obtidas com as amostras. O ingrediente base usado para formulação e fonte de proteína foi o concentrado protéico de soro de leite (WPC), obtido experimentalmente, através da utilização das tecnologias de membranas, ultrafiltração (UF) e diafiltração (DF), através de três experimentos distintos. Inicialmente, 30 litros de soro em pó reconstituído, foram concentrados através da ultrafiltração, com redução do volume para cinco litros, a partir deste volume realizaram-se as diafiltrações. No primeiro experimento executaram-se quatro DF, duas de cinco litros e duas de 2,5 litros, obtendo-se WPC-1 com 56% de proteína. No segundo experimento também com quatro DF, executaram-se dois deles com 10 litros e dois com cinco litros, obtendo-se o WPC-2, com 71% de proteína. Para o terceiro experimento, os ciclos das diafiltrações foram aumentados para seis DF de cinco litros cada, obtendo-se o WPC-3, com 80% de proteína. Os concentrados obtidos foram liofilizados e caracterizados em relação a suas propriedades funcionais, sendo a solubilidade a mais importante por estar diretamente ligada à utilização em formulações alimentares de bebidas. Obteve-se solubilidade média de 70, 77 e 85% para WPC-1, 2 e 3 respectivamente. Pelas características obtidas de concentração de proteínas e percentual de solubilidade, o concentrado protéico obtido no terceiro experimento foi o selecionado para ser utilizado na formulação. Esta ficou constituída de 68% de concentrado protéico de soro de leite, 2% de mix de vitaminas e minerais e 30% do agente espessante (goma guar). Através de testes preliminares realizados com o agente espessante, determinou-se a porção do produto formulado necessária de ser adicionada aos líquidos para que os mesmos atingissem os níveis de consistência desejados, ou seja, 4,2 g para consistência de néctar (50 – 351 cP), 6,7 g para consistência de mel (351-1750 cP) e 9,2 g para consistência de pudim (> 1750 cP), tradicionalmente recomendadas para indivíduos disfásicos, segundo o National Dysphagia Diet Guidelines (NDD). Diferentes amostras (leite, sucos de abacaxi, de uva e de laranja) foram espessadas e realizadas medidas da viscosidade aparente, expressas em centipoise (cP), nos tempos pós-preparo: 10 minutos, 2 horas com taxa de cisalhamento (“shear rate”) de 50s-1 a 25ºC. As amostras foram armazenadas sob refrigeração e após 24 horas, novas medidas foram realizadas com taxa de cisalhamento de 50s-1 a 10ºC. Houve diferença estatística significativa entre as médias de viscosidade nos tempos de preparo de todos os níveis de consistência, demonstrando que o agente espessante utilizado continuou agindo, hidratando-se e aumentando a viscosidade com o passar do tempo. Também foi encontrada diferença significativa entre algumas amostras, com diferentes líquidos de diluição, quando comparadas entre si no mesmo nível de consistência. No entanto, as amostras apresentaram viscosidade dentro dos níveis sugeridos pela National Disfagic Diet, com exceção da consistência de pudim que, no tempo 10 minutos, permaneceu abaixo dos limites, adequando-se com o tempo, para o consumo de indivíduos disfágicos. / The swallowing is a coordinated and extremely complex process, involving contractions and inhibitions of muscles located between the mouth and the stomach. Alterations on this system can generate dysphagia, common sign of several organic diseases, neurological alterations or neuromuscular diseases, producing in the patient difficulty in the mastication and Swallowing of food .To provide safe swallowing for dysphagic individuals is a challenge, however, this can be facilitated, if the food has modified texture and if the liquids are thickened. In this way, the purpose of this work was to develop a formulation of food thickener, with aggregated nutritional value, to thicken different liquid foods, giving them an appropriate consistence for dysphagic individuals and to evaluate its action in different liquid foods, testing the influence of the time of thickening and temperature, over the stability of the viscosities obtained by the samples. As ingredient base for formulation and protein source was used whey protein concentrate (WPC), obtained experimentally, through the use of the technologies of membranes, the ultrafiltration (UF) and diafiltration (DF), through three different experiments. Initially, 30 liters of reconstituted powder serum, were concentrate through ultrafiltration, with reduction of the volume for cinco liters, starting from this volume the diafiltration took place. In the first experiment quatro DF were executed, two of cinco liters and two of 2.5 liters, obtained WPC-1 with 56% of protein. In the second experiment quatro DF were executed, two of them with 10 liters and two with cinco liters, obtaining WPC-2 with 71% of protein. For the third experiment, the cycles of the diafiltration were increased for 6 DF of 5 liters each, obtaining WPC-3 with 80% of protein.The obtained concentrates were liofilized and characterized in relation to its functional properties, being the solubility the most important for being directly linked to the use in alimentary formulations and drink. Average solubility of 70, 77 and 85% were obtained for WPC, 1, 2 and 3 respectively. Due to the obtained characteristics of protein concentrate and its solubility, the WPC obtained in the third experiment was selected for if used in the formulation. This was constituted of 68% of whey protein concentrate, 2% of mix of Vitamins and Minerals and 30% of the thickning agent (gum guar). Through preliminary tests accomplished with the thickening agent the amount of formulated product necessary to reach the desired consistence levels was determined, being 4.2 g for nectar consistence (50 – 351 cP), 6.7 g for honey consistence (351-1750 cP) and 9.2 g for pudding (> 1750 cP), traditionally recommended for dysphagic individuals according to National Dysphagia Diet Guidelines (NDD). Different samples (milk, pineapple juices, and grape and orange) were thickened and measurements of apparent viscosity were carried out, expressed in centipoise (cP), in the times after preparation: 10 minutes, 2 hour with shear rate of 50s-1 to 25±2ºC. The samples were stored under refrigeration and after 24 hours, new measurements were accomplished with shear rate of 50 s-1 to 10±2ºC. There were significant statistic difference among the average viscosity in the times of preparation of all the consistence levels, demonstrating that the thickening agent used continued acting, increasing the viscosity in the course of time. As well as significant differences among some samples when compared to each other in the same consistence level, caused by the different constituents of the drinks taken as sample. However, all samples presented viscosity inside the levels suggested by National Dysphagic Diet, except for the pudding consistence that, in the time of 10 minutes, was below these limits, fitting with time, being for this inside the levels suggested, appropriated for consumption by dysphagic individuals.
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Qualidade físico-química de ovos comerciais submetidos a diferentes métodos de tratamento de casca e condições de estocagem / Physical-chemical quality of commercial eggs subjected to different treatment methods bark and storage timeAlmeida, Dayane Santos de 17 July 2013 (has links)
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Previous issue date: 2013-07-17 / The process of washing eggs positively influences the acceptance of the product by the consumer, because it improves the appearance for marketing and reduces the likelihood of contamination and threat to food security. However, hygiene is a subject that still generates controversy when it comes to egg s quality, since physical damage to the product may occur, since the protective cuticle that covers the shell is removed. Consequently, the eggs are more exposed to the exchange of gases and moisture and the entry of microorganisms, speeding the process of deterioration. The proteins in whey are gaining prominence in covering food products , because when properly processed , produce flexible, transparent and odorless coverage , being able to promote the closing of the pores of the egg shell and the reduction of moisture loss and transport gas , extending the storage time . The objective of this study was to evaluate the physical and chemical quality of commercial eggs undergo the processes of cleaning and soaking in whey protein concentrate (WPC), a function of storage time . There was the physical and chemical quality of 560 commercial eggs from semi-heavy laying strain of Hissex Brown, with 74 weeks of age. The design was completely randomized in a factorial 4 x 7, four methods of treating bark (non-sanitized and not covered with WPC, non-sanitized and covered with WPC, sanitized and not covered with WPC and sanitized and covered with WPC) and seven storage periods (1, 7, 14, 21, 28, 35 and 42 days), totaling 28 treatments, with five replicates of four eggs each. Quality parameters evaluated were weight loss of eggs (%), specific gravity (g/cm3), Haug unit (HU), yolk index (GI) and albumen pH / O processo de lavagem dos ovos influencia positivamente à
aceitação do produto pelo consumidor, pois melhora a aparência para
comercialização, além de diminuir a probabilidade de contaminação e
ameaça à segurança alimentar. No entanto, a higienização é um assunto
que ainda gera polêmica em se tratando de qualidade de ovos, uma vez
que podem ocorrer danos físicos ao produto, já que a cutícula protetora
que recobre a casca é removida. Por conseqüência, os ovos ficam mais
expostos à troca de gases e umidade e à entrada de microrganismos,
acelerando seu processo de deterioração. As proteínas do soro de leite
vêm ganhando destaque na cobertura de produtos alimentícios, pois
quando processadas apropriadamente, produzem coberturas flexíveis,
transparentes e sem odores, sendo capazes de promover o fechamento
dos poros da casca do ovo e a diminuição da perda de umidade e do
transporte de gases, prolongando o tempo de estocagem. O objetivo
deste trabalho foi avaliar a qualidade físico-química de ovos comerciais
submetidos aos processos de higienização e imersão em solução de
concentrado protéico de soro do leite (CPSL), em função do tempo de
armazenamento. Verificou-se a qualidade físico-química de 560 ovos
comerciais provenientes de poedeiras semipesadas da linhagem Hissex
Brown, com 74 semanas de idade. O delineamento foi inteiramente ao
acaso, em arranjo fatorial 4 x 7, sendo quatro métodos de tratamento de
casca (não-higienizados e não cobertos com CPSL; não-higienizados e
cobertos com CPSL; higienizados e não cobertos com CPSL e
higienizados e cobertos com CPSL) e sete períodos de estocagem (01,
07, 14, 21, 28, 35 e 42 dias), totalizando 28 tratamentos, com cinco
repetições de quatro ovos cada. Os parâmetros de qualidade avaliados
foram perda de peso dos ovos (%), gravidade específica (g/cm3),
unidade Haug (UH), índice de gema (IG) e pH de albúmen.
Também foram avaliados o perfil protéico do albúmen,
utilizando-se pools cinco ovos por tratamento, e a oxidação lipídica da
gema, através dos valores de TBARS, as quais foram realizadas em
quintuplicata. O aumento no período de estocagem, independente do
método de tratamento de casca, ocasionou perda de peso nos ovos,
reduções na gravidade específica, na unidade Haugh e no índice de
gema, aumento no pH do albúmen e nos valores de TBARS. Não houve
modificação no perfil protéico do albúmen entre os métodos de
tratamento de casca ao longo do armazenamento. O método de
higienização faz com que piore a qualidade interna do ovo com o
decorrer do armazenamento. A cobertura de concentrado protéico de
soro do leite é uma alternativa viável para a conservação de ovos
comerciais armazenados em temperatura ambiente por minimizar a
perda de qualidade físico-química ao longo do armazenamento,
inclusive de ovos que necessitam passar pelo processo de higienização
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Estudo da fabricação de requeijão cremoso com diferentes concentrações de gordura no extrato seco, sal emulsificante e concentrado proteico de soro obtido por ultrafiltração / Requeijão cremoso manufacture study with different concentrations of fat on dry matter, emulsifying salt and whey protein concentrate obtained by ultrafiltrationLubeck, Gert Marcos 02 August 2006 (has links)
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Previous issue date: 2005 / Resumo: Este trabalho constitui em desenvolver tecnologia de fabricação de requeijão cremoso utilizando concentrado oretéico de soro ultrafiltrado e estudar as caracteristicas fisico-quimicas, de textura instrumental e sensorial, capacidade de derretimento de queijo, propriedades reológicas e de caracterização sensorial dos produtos. A fabricação dos produtos foi realizada nas instalações da Indústria de Laticínios Bombardelli em condições de processo industrial. Na 1ª etapa foram realizados dois experimentos. O primeiro experimento avaliou a possibilidade do aproveitamento do concentrado protéicode soro (CPS), de massa coagulada com e sem lavagem da massa, e de utilização de diferentes fontes de gordura, como o creme de leite e a manteiga, na fabricação de requeijão cremoso. O segundo experimento avaliou pontos tecnológicos de processo de ovbtenção dos ingredientes de fabricação sos requeijões cremosos. Na 2ª etapa também foram realizados dois experimentos. O primeiro experimento consistiu na fabricação dos requeijões cremosos utilizando quatro níveis de CPS (6,8, 10 e 12%) e três níveis de gordura no extrato seco (GES) (55, 60e 65%). Foram avaliadas as caracteristicas fisico-quimicas dos ingredientes e, o fluxo de requeijão e os parâmetros de textura industrial dos produytos. Os produtos fabricados foram comparados com requeijões comerciais. No segundo experimento foram utilizados cinco níveis de CPS (0, 6, 8, 10 e 12%) e três níveis de GES (55, 60, e 65%). Ocorreram diferenças significativas (p<0,05) entre as amostras de requeijão cremosos, em relação aos parâmetros de textura instrumental e teste de derretimento. A 3ª etapa consistiu de um experimento que permitiu a realização do estudo de análise sensorial que incluiu o teste de aceitação a Análise Descritiva Quantitativa (ADQ) realizada por uma equipe sensorial de onze provadores. Foram avaliadas 15 amostras de requeijão cremoso fabricadas com a adição de cinco níveis de concentrado protéico de soro e três níveis de sal emulsificante e quatro amostras comerciais de requeijão. Foram escolhidas pelo teste de aceitação as quatro melhores amostras de requeijão com CPS e uma amostra de requeijão comercial, considerando a aparência, aroma, sabor, consistência e espalhabilidade. Baseado nestes resultados, as cinco melhores amostras foram realizadas por meio de análise descritiva quantitativa, caracterizando os produtos, Foi avaliada a realção que existe entre as caracteristicas fisico-quimica com a capacidade de derretimento e parametros de textura instrumental (TPA) dos requeijões cremosos. A 4ª e ultima etapa consistiu de um experimento, em que se avaliou o efeito das variáveis de processo, pela incorporação de diferentes níveis de concentrado protéico de soro obtido por ultrafiltração de sal emulsificante sobre as respostas de textura instrumental e sensorial. O planejamento experimental consistiu de quatro ensaios, quatro pontos centrais, totalizando 12 ensaios. Obteve-se faixas ótimas de uso de CPS e SE que proporcionaram as melhores respostas sensoriais de cremosidade, pastosidadee espalhabilidade e de textura instrumental de dureza, adesividade, elasticidade e gomosidade. Obteve-se um índice reológico de comportamento (n) mínimo n = 0,51 para amostra 07 (produto mais viscoso) e máximo n = 0,80 para amostra 08 (produto menos viscoso) / Abstract: This work consisted to develop technology of manufacture of requeijão cremoso utilizing whey protein concentrate ultrafiltered and study the chemicalphysical characteristics, sensory and instrumental texture, melting cheese capacity, rheological properties and sensorial characteristics of products. The fabrication of products was realized in Bombardelli Dairy Industry in conditions insdustrial process. In the first stage, were realized two experiments. The first experiment evaluated the possibility of to use whey protein concentrate, soft coagulante curd with and without curd was, use of different fat sources as milk cream or butter in fabrication os requeijão cremoso. The second experiment, was realized to define the process fluxogram to be used and the operacional range of the variables to be studied. In second stage was realized two experiments again. First experiment consisted in manufactured requeijões cremosos utilizing 6, 8, 10 and 12% whey protein concentrate and three levels of fat dry matter (55, 60 and 65%) . Were evaluated chemicalphysical characteristics of the ingredients and, melting capacity and instrumental texture parameters (TPA) of products. In second experiment were utilized five levels whey protein concentrate (zero, 6, 8, 10 and 12%), and theree levels of fat dry matter (55, 60 and 65%). Ocurred significant difference (P<0,05) between samples of requeijões cremosos in relationship melting capacity and instrumental texture parameters (TPA). Third stage consisted of one experiment that permited the realization of sensory analysis, including acceptance test and Descriptive Quantitative Analysis (DQA) realized by eleven panelist judged. Were choosed by acceptance test lhe four better samples of requeijão with addition whey protein concentrate and one commercial sample of requeijão with base in appearance, flavour, tate, consistency and spreadly. Based in this results, the fivebetter samples were analised utilizing descriptive quantitative analysis, characterizing the products. Was evaluated the relationship there are between chemicalphysical characteristics and melting capacity and texture parameters (TPA) oj "requeijões cremosos". Fouth and final stage consisted also of one experiment, in that evaluated the process variables effects, by incorporation of differents levels whey protein concentrate obtained by ultrafiltration and emulsifying salt on the instrumental and sensorial texture responses. The experimental design included four assay, four axis point and four centre points, resulting in 12 experimetal runs. Obatained abtimize regions of use of whey protein concentrate and emulsifying salt that providing the better sensorial responses of cremosity, stickiness and spreadability and better instrumental textures responses of firmness, adesiviness, elasticity and gumniness. The sample seven had minimal flow rheological behaviour index (n=0,51 product more viscous) and sample eight had maximum flow rheological behaviour index (n=0,80 product lesser viscous) / Doutorado / Doutor em Tecnologia de Alimentos
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Desenvolvimento de espessante alimentar para líquidos com valor nutricional agregado, destinados a indivíduos disfágicos / Development of food thickner for liquids with aggregated nutritional value intended for dysphagic individualsPagno, Carlos Henrique January 2009 (has links)
A deglutição é um processo coordenado e extremamente complexo, envolvendo contração e inibição de músculos localizados entre a boca e o estômago. Alterações neste sistema podem gerar disfagia, sinal comum de diversas doenças orgânicas, alterações neurológicas ou doenças neuromusculares, produzindo no paciente dificuldade na mastigação e deglutição de alimentos. Prover deglutição segura para indivíduos disfágicos é um desafio, contudo, esta pode ser facilitada se os alimentos tiverem a textura modificada e os líquidos forem espessados. Dessa maneira, este trabalho teve por objetivo desenvolver uma formulação de espessante alimentar, com valor nutricional agregado, para espessar diferentes líquidos, tornando-os com consistência adequada para pacientes disfásicos e avaliar sua ação em diferentes líquidos, testando a influência do tempo de espessamento e temperatura, sobre a estabilidade das viscosidades obtidas com as amostras. O ingrediente base usado para formulação e fonte de proteína foi o concentrado protéico de soro de leite (WPC), obtido experimentalmente, através da utilização das tecnologias de membranas, ultrafiltração (UF) e diafiltração (DF), através de três experimentos distintos. Inicialmente, 30 litros de soro em pó reconstituído, foram concentrados através da ultrafiltração, com redução do volume para cinco litros, a partir deste volume realizaram-se as diafiltrações. No primeiro experimento executaram-se quatro DF, duas de cinco litros e duas de 2,5 litros, obtendo-se WPC-1 com 56% de proteína. No segundo experimento também com quatro DF, executaram-se dois deles com 10 litros e dois com cinco litros, obtendo-se o WPC-2, com 71% de proteína. Para o terceiro experimento, os ciclos das diafiltrações foram aumentados para seis DF de cinco litros cada, obtendo-se o WPC-3, com 80% de proteína. Os concentrados obtidos foram liofilizados e caracterizados em relação a suas propriedades funcionais, sendo a solubilidade a mais importante por estar diretamente ligada à utilização em formulações alimentares de bebidas. Obteve-se solubilidade média de 70, 77 e 85% para WPC-1, 2 e 3 respectivamente. Pelas características obtidas de concentração de proteínas e percentual de solubilidade, o concentrado protéico obtido no terceiro experimento foi o selecionado para ser utilizado na formulação. Esta ficou constituída de 68% de concentrado protéico de soro de leite, 2% de mix de vitaminas e minerais e 30% do agente espessante (goma guar). Através de testes preliminares realizados com o agente espessante, determinou-se a porção do produto formulado necessária de ser adicionada aos líquidos para que os mesmos atingissem os níveis de consistência desejados, ou seja, 4,2 g para consistência de néctar (50 – 351 cP), 6,7 g para consistência de mel (351-1750 cP) e 9,2 g para consistência de pudim (> 1750 cP), tradicionalmente recomendadas para indivíduos disfásicos, segundo o National Dysphagia Diet Guidelines (NDD). Diferentes amostras (leite, sucos de abacaxi, de uva e de laranja) foram espessadas e realizadas medidas da viscosidade aparente, expressas em centipoise (cP), nos tempos pós-preparo: 10 minutos, 2 horas com taxa de cisalhamento (“shear rate”) de 50s-1 a 25ºC. As amostras foram armazenadas sob refrigeração e após 24 horas, novas medidas foram realizadas com taxa de cisalhamento de 50s-1 a 10ºC. Houve diferença estatística significativa entre as médias de viscosidade nos tempos de preparo de todos os níveis de consistência, demonstrando que o agente espessante utilizado continuou agindo, hidratando-se e aumentando a viscosidade com o passar do tempo. Também foi encontrada diferença significativa entre algumas amostras, com diferentes líquidos de diluição, quando comparadas entre si no mesmo nível de consistência. No entanto, as amostras apresentaram viscosidade dentro dos níveis sugeridos pela National Disfagic Diet, com exceção da consistência de pudim que, no tempo 10 minutos, permaneceu abaixo dos limites, adequando-se com o tempo, para o consumo de indivíduos disfágicos. / The swallowing is a coordinated and extremely complex process, involving contractions and inhibitions of muscles located between the mouth and the stomach. Alterations on this system can generate dysphagia, common sign of several organic diseases, neurological alterations or neuromuscular diseases, producing in the patient difficulty in the mastication and Swallowing of food .To provide safe swallowing for dysphagic individuals is a challenge, however, this can be facilitated, if the food has modified texture and if the liquids are thickened. In this way, the purpose of this work was to develop a formulation of food thickener, with aggregated nutritional value, to thicken different liquid foods, giving them an appropriate consistence for dysphagic individuals and to evaluate its action in different liquid foods, testing the influence of the time of thickening and temperature, over the stability of the viscosities obtained by the samples. As ingredient base for formulation and protein source was used whey protein concentrate (WPC), obtained experimentally, through the use of the technologies of membranes, the ultrafiltration (UF) and diafiltration (DF), through three different experiments. Initially, 30 liters of reconstituted powder serum, were concentrate through ultrafiltration, with reduction of the volume for cinco liters, starting from this volume the diafiltration took place. In the first experiment quatro DF were executed, two of cinco liters and two of 2.5 liters, obtained WPC-1 with 56% of protein. In the second experiment quatro DF were executed, two of them with 10 liters and two with cinco liters, obtaining WPC-2 with 71% of protein. For the third experiment, the cycles of the diafiltration were increased for 6 DF of 5 liters each, obtaining WPC-3 with 80% of protein.The obtained concentrates were liofilized and characterized in relation to its functional properties, being the solubility the most important for being directly linked to the use in alimentary formulations and drink. Average solubility of 70, 77 and 85% were obtained for WPC, 1, 2 and 3 respectively. Due to the obtained characteristics of protein concentrate and its solubility, the WPC obtained in the third experiment was selected for if used in the formulation. This was constituted of 68% of whey protein concentrate, 2% of mix of Vitamins and Minerals and 30% of the thickning agent (gum guar). Through preliminary tests accomplished with the thickening agent the amount of formulated product necessary to reach the desired consistence levels was determined, being 4.2 g for nectar consistence (50 – 351 cP), 6.7 g for honey consistence (351-1750 cP) and 9.2 g for pudding (> 1750 cP), traditionally recommended for dysphagic individuals according to National Dysphagia Diet Guidelines (NDD). Different samples (milk, pineapple juices, and grape and orange) were thickened and measurements of apparent viscosity were carried out, expressed in centipoise (cP), in the times after preparation: 10 minutes, 2 hour with shear rate of 50s-1 to 25±2ºC. The samples were stored under refrigeration and after 24 hours, new measurements were accomplished with shear rate of 50 s-1 to 10±2ºC. There were significant statistic difference among the average viscosity in the times of preparation of all the consistence levels, demonstrating that the thickening agent used continued acting, increasing the viscosity in the course of time. As well as significant differences among some samples when compared to each other in the same consistence level, caused by the different constituents of the drinks taken as sample. However, all samples presented viscosity inside the levels suggested by National Dysphagic Diet, except for the pudding consistence that, in the time of 10 minutes, was below these limits, fitting with time, being for this inside the levels suggested, appropriated for consumption by dysphagic individuals.
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