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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

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.
52

Efeito da Suplementação da Proteína do Soro do Leite na Saúde Óssea de Mulheres na Pós-Menopausa em Programa de Modificação do Estilo de Vida com Exercícios Físicos e Adequação Alimentar

Gollino, Loraine. January 2019 (has links)
Orientador: Eliana Aguiar Petri Nahas / Resumo: Objetivo: Avaliar se a suplementação da proteína do soro do leite (PSL) melhora a reabsorção óssea, em mulheres na pós-menopausa praticantes de exercício físico. Métodos: Estudo prospectivo de intervenção controlado, com 38 mulheres na pós-menopausa, com idade entre 50 a 70 anos, randomizadas em dois grupos: intervenção com PSL (n=19) ou controle (n=19). Foram incluídas mulheres com amenorreia acima de 12 meses, densitometria óssea normal dos últimos doze meses e praticantes do protocolo de exercícios físicos (especificar mais). O treinamento foi realizado três vezes por semana, composto de exercícios aeróbio e resistido. No grupo suplementado foi fornecido PSL, para ingestão diária, contendo 25g de proteína. O tempo de seguimento foi de 20 semanas, com avaliações nos momentos (inicial e final). As participantes foram avaliadas quanto à antropometria, ao consumo alimentar por meio do recordatório de 24 horas, variável laboratorial (bioquímicos e hormonais) e pelo marcador de reabsorção óssea, o s-CTX (serum C-terminal cross-linked telopeptides of type I collagen). A análise estatística foi per protocol, empregando-se delineamento em medidas repetidas no tempo (ANOVA), seguido do teste de comparação múltipla de Tukey ajustado para interação entre grupo x momento ou por distribuição Gama (variáveis assimétricas). Resultados: O estudo foi finalizado com 18 mulheres no grupo suplementado e 14 no grupo controle, com média de idade de 59±6 anos. Quanto aos parâmetros antropométrico... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Objective: To evaluate the effect of whey protein supplementation (WPS) on bone resorption in postmenopausal women practicing physical exercise. Methods: We conducted a prospective, controlled study with 38 postmenopausal women aged 50 to 70 years, randomized into two groups: with PSL intervention (n = 19) or without PSL (n = 19, control). We included women with amenorrhea above 12 months, normal bone mineral density of the last twelve months and practitioners of the physical exercise protocol. The exercises were performed three times a week with aerobic and resistance training. In the intervention group, supplementation was provided daily, containing 25g of protein. Follow-up time was 20 weeks, with assessments at the start and end times. The participants were evaluated for anthropometry, food consumption through the 24-hour recall, laboratory parameters (biochemical and hormonal) and the bone resorption marker s-CTX (serum Cterminal cross-linked telopeptides of type I collagen). Statistical analysis was per protocol, using a time-repeated measures (ANOVA) followed by the Tukey multiple comparison test adjusted for group x moment interaction, or by gamma distribution (asymmetric variables). Results: We evaluated 18 women in the supplemented group and 14 in the control group, mean age 59±6 years. Regarding the anthropometric and laboratory parameters, no significant differences were observed between groups. In relation to the food consumption, at the initial moment, it was ob... (Complete abstract click electronic access below) / Doutor
53

Polimorfismo no Gene que Codifica a ?-lactoglobulina e associa??o com caracter?sticas de produ??o em caprinos leiteiros / Polymorphism in the gene encoding the ?-lactoglobulin and Association with Traditional Production in Dairy Goats

Rego, Ramon de Sousa 26 August 2014 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-18T11:49:54Z No. of bitstreams: 1 2014 - Ramon de Sousa Rego.pdf: 1491511 bytes, checksum: 746021e21f53b13713de3e8e94d03121 (MD5) / Made available in DSpace on 2016-10-18T11:49:54Z (GMT). No. of bitstreams: 1 2014 - Ramon de Sousa Rego.pdf: 1491511 bytes, checksum: 746021e21f53b13713de3e8e94d03121 (MD5) Previous issue date: 2014-08-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The protein quality of milk of goats and digestibility of the lipid fraction are important factors that stand out when compared to milk from cows. The ?-lactoglobulin is the higher abundant protein in whey ruminants being produced in the mammary gland during lactation. It may represent up to 12% of the total protein. We seek to present work was to evaluate the gene ?-Lactoglobulin (BLG) with their genetic polymorphisms in the promoter regions 5 'and 3' UTR and associate them the characteristics of milk production in experimental goat herd. For this 150 goats (Capra hircus) of Saanen and Alpine, genotyped for polymorphisms of the BLG gene were used. For genotyping 10 mL of blood per animal were collected. The blood was used for DNA extraction and amplification of two fragments of the BLG gene by means of polymerase chain reaction (PCR). The amplified fragments were submitted to electrophoresis on polyacrylamide gel and evaluated by by restriction fragment length polymorphism (PCR-RFLP). The SmaI and SacII enzymes were used for the promoter (promoter + exon 1 region) region and the region of exon 7 (exon 7 + region 3 '), respectively. The differences in cutting patterns were visualized on a polyacrylamide gel. In the promoter region of the single nucleotide polymorphism (SNP) at position -60 (C/T) was identified and was associated with the percentage of protein in milk. This result suggests a relationship between genotypes of the promoter region of the BLG gene and the protein level of the milk. The presence of two polymorphisms +4641 (I2/I3) and +4601 (A/G) was observed in the region of exon 7. The I2-I3 variation is characterized by a repeat sequence of 10 bp, varying in two and three times, and it being possible to identify by electrophoresis. The I3 variation was often very low, and there was no association between this polymorphism and any production trait. Polymorphism +4601 (G/A) was identified by enzyme SacII digestion. Alleles were identified frequencies close to those reported by other authors and were associated with the percentage of fat in milk goats, and the animals with the S1S2 genotype had higher fat percentage than S1S1 animals and S2S2. The increased production of lipid content may be related to the characteristic of transporting fatty acids ?-lactoglob / A qualidade proteica do leite de cabras e a digestibilidade da fra??o lip?dica s?o importantes fatores que o destacam, quando comparado ao leite de vacas. A ?-Lactoglobulina ? a prote?na de maior abundancia no soro do leite em ruminantes sendo produzida na gl?ndula mam?ria durante o per?odo de lacta??o. Ela pode representar at? 12% do total proteico. Buscamos com o presente trabalho, avaliar o gene da ?-Lactoglobulina (BLG) com seus polimorfismos gen?ticos nas regi?es promotoras 5? e 3? UTR e associ?-los as caracter?sticas de produ??o de leite no rebanho caprino experimental. Para isso foram utilizadas 150 cabras (Capra hircus) das ra?as Saanen e Alpinas, genotipadas para os polimorfismos do gene BLG. Para a genotipagem foram coletados 10 mL de sangue por animal. O sangue foi utilizado para a extra??o de DNA e amplifica??o de 2 fragmentos do gene BLG por interm?dio da rea??o em cadeia da polimerase (PCR). Os fragmentos amplificados foram ent?o submetidos ? eletroforese em gel de poliacrilamida e avaliados pelo polimorfismo no tamanho do fragmento por restri??o (PCR-RFLP). Foram utilizadas as enzimas SmaI e SacII, para a regi?o promotora (regi?o promotora + ?xon 1) e para a regi?o do ?xon 7 (?xon 7 + regi?o 3?), respectivamente. As diferen?as nos padr?es de corte foram visualizadas em gel de poliacrilamida. Na regi?o promotora o polimorfismo de base ?nica (SNP) na posi??o -60 (C/T) foi identificado e apresentou associa??o com a percentagem de prote?nas no leite. Esse resultado sugere uma rela??o entre os gen?tipos da regi?o promotora do gene BLG e o n?vel proteico do leite. Foi observado na regi?o do ?xon 7 a presen?a de dois polimorfismos +4641 (I2/I3) e +4601 (A/G). A varia??o I2-I3 ? caracterizada pela repeti??o de uma sequ?ncia de 10 pb, variando em duas e tr?s vezes, e sendo poss?vel identifica-la por eletroforese. A varia??o I3 teve frequ?ncia muito baixa, e n?o houve associa??o entre esse polimorfismo e nenhuma caracter?stica de produ??o. O polimorfismo +4601 (A/G) foi identificado por meio da digest?o da enzima SacII. Os alelos identificados tiveram frequ?ncias pr?ximas ?s relatadas por outros autores e apresentaram associa??o com a percentagem de gordura no leite cabras, sendo que os animais com o gen?tipo S1S2 apresentaram maior percentagem de gordura que animais S1S1 e S2S2. A maior produ??o de conte?do lip?dico pode estar relacionada com a caracter?stica de transporte de ?cidos graxos da ?-Lactoglobulina
54

Nano-dispersing Lipophilic Antimicrobials for Improved Food Safety

Shah, Bhavini Dipak 01 December 2011 (has links)
Naturally occurring food antimicrobials such as plant essential oils are receiving tremendous interest as intervention systems to enhance microbiological safety and quality. Poor water solubility of essential oils makes it difficult to incorporate them in foods, impacting visual appearance, antimicrobial effectiveness, and possibly organoleptic properties. Engineered nanoscale delivery systems can principally solve these challenges, but those based on low-cost food ingredients and inexpensive and scalable processes are currently scarce. This dissertation presents a simple and scalable two-step technology to prepare nano-delivery systems. The first encapsulation step, based on emulsion-evaporation, involves preparing emulsions composed of an oil phase with thymol or eugenol, major compounds in extracts from thyme and clove respectively, in hexane and an aqueous phase with conjugates of whey protein isolate and maltodextrin, followed by evaporation of hexane by spray drying. The second step is to hydrate spray dried capsules to enable the formation of nanoscale particles. The encapsulation performance and dispersion characteristics were affected by amounts and types of conjugates (ratio of protein: maltodextrin and maltodextrin chain length), volume fraction and composition of the oil phase. The optimal conditions corresponded to 55.8 % encapsulation efficiency and 12.6 % loading for thymol and 47.9 % encapsulation efficiency and 7.9 % loading for eugenol. Dispersions prepared from the identified capsules contained particles smaller than 100 nm and were transparent at pH 3.0-7.0 and 0-50 mM before and after heating at 80°C for 15 min. Nano-dispersions and free oil were tested for antimicrobial activity against Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, and Salmonella typhimurium. Nano-dispersed and free antimicrobials had similar effectiveness at various pH and temperatures in tryptic soy broth and apple cider, while in 2 % reduced fat milk, nano-dispersed antimicrobials were consistently more effective than unencapsulated ones. Therefore, the commercially viable nanoscale technology presented in this study enables the delivery of lipophilic antimicrobials for enhanced microbial safety and quality, without compromising visual appearance of foods, especially clear beverages.
55

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 Zealand

Patel, 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.
56

Variation in milk protein composition and its importance for the quality of cheese milk /

Wedholm, Anna, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2008. / Härtill 5 uppsatser.
57

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 individuals

Pagno, 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.
58

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 individuals

Pagno, 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 time

Almeida, Dayane Santos de 17 July 2013 (has links)
Made available in DSpace on 2016-12-08T16:24:18Z (GMT). No. of bitstreams: 1 PGCA13MA141.pdf: 78545 bytes, checksum: 8ec31bb3352da0cbb2aeb6ecf2cb0871 (MD5) 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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Aplica??o do planejamento de experimentos no processo de desenvolvimento de produtos: pesquisa em uma sorveteria artesanal / Design of experiments in product development: a research in an artisanal gelato

Ara?jo J?nior, Luciano Queiroz de 27 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-22T22:00:15Z No. of bitstreams: 1 LucianoQueirozDeAraujoJunior_DISSERT.pdf: 3664200 bytes, checksum: 4349858cb22e75402e8ea95d104b6724 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-24T21:06:03Z (GMT) No. of bitstreams: 1 LucianoQueirozDeAraujoJunior_DISSERT.pdf: 3664200 bytes, checksum: 4349858cb22e75402e8ea95d104b6724 (MD5) / Made available in DSpace on 2016-02-24T21:06:03Z (GMT). No. of bitstreams: 1 LucianoQueirozDeAraujoJunior_DISSERT.pdf: 3664200 bytes, checksum: 4349858cb22e75402e8ea95d104b6724 (MD5) Previous issue date: 2015-02-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / As constantes evolu??es nos sistemas de produ??o tem procurado atender, em grande parte, ?s necessidades dos clientes. O mercado, desde ent?o, vem se tornando cada vez mais competitivo. Neste contexto de busca de um diferencial competitivo para impressionar os clientes e fideliz?-los a posteriori, as empresas tem apostado no desenvolvimento de novos produtos. A falta de uma gest?o clara e um m?todo no Processo de Desenvolvimento de Produtos (PDP) pode fazer com que as empresas n?o consigam incorporar novas tecnologias que resultem em melhorias significativas. A maioria das Micro e Pequenas Empresas (MPEs) n?o tem uma metodologia de PDP definida, e por muitas vezes acabam ainda se baseando na experi?ncia emp?rica dentro da empresa. Existem muitas ferramentas estat?sticas que auxiliam nesse processo, dentre elas o Planejamento de Experimentos, que ? uma t?cnica utilizada para se planejar experimentos, ou seja, para definir quais dados, em que quantidade e em que condi??es devem ser coletados durante um determinado experimento, buscando, basicamente, satisfazer dois grandes objetivos: a maior precis?o estat?stica poss?vel na resposta e o menor custo. O objetivo desta disserta??o, portanto, ? propor uma metodologia de desenvolvimento de novos produtos, utilizando a t?cnica de planejamento de experimentos, em uma pequena empresa do ramo aliment?cio. O estudo foi realizado em uma sorveteria artesanal e o produto escolhido para a realiza??o da pesquisa foi um sorvete ? base de um suplemento alimentar prote?co, o Whey Protein. A fim de conduzir a pesquisa foi elaborado uma metodologia baseada em 8 passos: (1) Concep??o da ideia; (2) Ouvir a voz dos clientes; (3) Ouvir a voz dos especialistas; (4) Identifica??o dos par?metros de interesse; (5) Planejamento de Experimentos; (6) An?lise; (7) Otimiza??o; (8) Lan?amento do Produto. Para a concep??o da ideia foram realizadas entrevistas com dois grupos focos: grupo de oito pessoas, incluindo esportistas e atletas e um outro de cinco pessoas, incluindo nutricionistas e educadores f?sicos. O desenvolvimento do produto se deu em tr?s etapas: na primeira foi realizado um experimento de um ?nico fator para entender a composi??o da base do sorvete. Na segunda foi realizado um fatorial completo, com foco nos fatores fibras, prote?nas e ?gua. Na terceira etapa outro fatorial completo, com foco nos mesmos fatores. Ao longo do desenvolvimento do sorvete, foram conduzidos testes sensoriais e de composi??o centesimal do produto para fazer a valida??o do mesmo de acordo com os requisitos dos stakeholders e da legisla??o vigente, respectivamente. Ao final do produto, pode-se afirmar que a nova metodologia de desenvolvimento de produto obteve um resultado de sucesso, com um produto inovador no mercado e melhorando aspectos da gest?o da informa??o dentro da organiza??o estudada. Destaca-se como positivo a empresa possuir um ?timo ambiente de inova??o, que se caracteriza por ser bastante aberto a ideias novas e ousadas. Sugere-se a aplica??o desta metodologia em outras MPEs a fim de melhorar a gest?o da inova??o.

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