Orientador: Caroline Joy Steel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-06T15:43:12Z (GMT). No. of bitstreams: 1 Almeida_EvelineLopes_M.pdf: 15471832 bytes, checksum: b43c4088e42981acaea0df1073c7d74c (MD5) Previous issue date: 2006 / Resumo: O objetivo deste trabalho foi estudar o efeito da adição de diferentes fontes de fibra alimentar em pão convencional e em pão pré-assado congelado. Um delineamento composto central rotacional (DCCR) foi utilizado, com as porcentagens das diferentes fontes de fibra alimentar - farelo de trigo, amido resistente e locust bean gum (LBG) - sendo as variáveis independentes. O delineamento incluiu dezoito ensaios: oito pontos fatoriais, seis pontos axiais e quatro repetições do ponto central. Os resultados foram analisados pela Metodologia de Superfície de Resposta. Os níveis de farelo de trigo, amido resistente e LBG usados foram, respectivamente: 0-20%, 0-20% e 0-3% (base farinha). As variáveis dependentes foram parâmetros farinográficos das combinações de farinha de trigo e fontes de fibra, parâmetros do processo de panificação (tempo de mistura rápida e tempo de fermentação) e características de qualidade dos pães (volume específico, cor instrumental da crosta e do miolo, aceitação sensorial, vida de prateleira avaliada através da umidade do miolo e dureza dos pães após um, quatro e sete dias do forneamento). O efeito do período de estocagem congelada (0, 32 ou 62 dias) foi avaliado através da submissão da média dos dados das características de qualidade dos pães dos dezoito ensaios do planejamento à análise de variância e teste de Tukey. Os resultados mostraram que as fontes de fibra alimentar modificaram a absorção de água e as propriedades de mistura da farinha de trigo, interferiram no tempo de mistura rápida do processo e nas características tecnológicas do pão, como volume, cor, umidade e dureza. No entanto, notou-se que as modificações tecnológicas não inviabilizaram os produtos, uma vez que eles foram bem aceitos sensorialmente e apresentaram uma alta intenção de compra pelos provadores. Verificou-se que o aumento do tempo de estocagem congelada, de 32 para 62 dias, não teve grande interferência na maioria das características dos pães analisados. Concluiu-se que foi possível a produção de pães convencionais e pães pré-assados congelados com fibras que atendem à legislação brasileira para fins de rotulagem nutricional de fibra alimentar (considerados fonte e/ou alto teor de fibras), com parâmetros tecnológicos e sensoriais que os permitem ser considerados produtos de boa qualidade / Abstract: The aim of this work was to study the effect of adding different dietary fiber sources to conventional bread and to frozen part-baked bread. A central composite rotational design (CCRD) was used, with the percentages of the different dietary fiber sources ¿ wheat bran, resistant starch and locust bean gum (LBG) ¿ being the independent variables. The design included eighteen trials: eight factorial points, six axial points and four repetitions of the central point. Results were analyzed using the Response Surface Methodology. The levels of wheat bran, resistant starch and LBG used were, respectively: 0-20%, 0-20% and 0-3% (flour basis). The dependent variables were farinographic parameters of the combinations of wheat flour and dietary fiber sources, baking process parameters (rapid mixing time and proofing time) and bread quality characteristics (specific volume, crust and crumb instrumental color, sensory acceptance, shelf-life evaluated through crumb moisture and bread hardness after one, four and seven days from baking). The effect of the frozen storage period (0, 32 or 62 days) was evaluated by the submission of the average values of the bread quality characteristics of the eighteen trials of the experimental design to Analysis of Variance and the Tukey test. The results showed that the dietary fiber sources modified the water absorption and the mixing properties of the wheat flour, interfered in the rapid mixing time and in the technological characteristics of bread, such as volume, color, moisture and hardness. Nevertheless, it was shown that the technological modifications did make the products unfeasible, as they had a good sensory acceptance and a high buying intention by the panelists. It was observed that the increase of frozen storage time, from 32 to 62 days, did not greatly affect most of the bread characteristics analyzed. It was concluded that it was possible to produce conventional and frozen part-baked breads with fiber that attend the Brazilian legislation regarding nutritional labeling claims related to dietary fiber (breads that can be considered sources and/or high fiber content), having technological and sensory parameters that permit them to be considered good quality products / Mestrado / Mestre em Tecnologia de Alimentos

Made available in DSpace on 2014-08-20T14:38:44Z (GMT). No. of bitstreams: 1 Dissertacao_Juliana_Girardon.pdf: 735964 bytes, checksum: 63e3eac19eea956ffade85e6e6de5e54 (MD5) Previous issue date: 2011-03-25 / This study aimed to investigate four forced-moulting methods on productive performance and egg quality of brown-egg layers. A total of 448 100 week-old laying hens were fed experimental diets during 148 days (from August to December of 2009). The experimental design was a completely randomized block design, with 16 replicates per treatment. Treatments consisted of: 1) fasting during 14 days; 2) soybean hulls based diet; 3) wheat bran based diet and 4) High tannin sorghum based diet. A post-moulting corn-soybean meal basal diet, formulated to fulfill nutrient requirement of birds was fed to the animals. Hens fed alternative ingredient based diets showed better performance. Productive performance, viability and decrease in egg production were similar between hens fed the soybean hulls based diet and those exposed to fasting. Birds fed high tannin showed lower mortality, but showed a lower egg production. Birds fed alternative ingredients showed 12% egg production at 6 days after the beginning of the experiment. These results indicate that hens fed alternative ingredient sources showed better performance than those exposed to fasting at the end of the first productive cycle. / Objetivou-se avaliar e verificar o desempenho produtivo, a eficiência da muda forçada e a qualidade dos ovos de poedeiras comerciais semipesadas de linhagem comercial, com 100 semanas de idade inicial, submetidas a quatro métodos nutricionais de muda forçada. O experimento foi realizado entre agosto de 2009 em dezembro de 2009, compreendendo 142 dias experimentais, utilizando-se 448 aves. O delineamento experimental utilizado foi completamente casualizado, com quatro tratamentos distribuídos por sorteio dentro das baterias, compostos por: 1) jejum de 14 dias; 2) ração à base de casca de soja; 3) ração à base de farelo de trigo e 4) ração à base de sorgo alto tanino, sendo cada tratamento com 16 repetições. As aves foram distribuídas em 64 gaiolas com sete aves em cada. A dieta basal do pós muda foi formulada à base de milho e farelo de soja, com níveis nutricionais estabelecidos pelo manual da linhagem de acordo com a fase produtiva. Foi observado melhor desempenho durante a muda, nas aves que receberam dietas alternativas. Para as variáveis produtivas analisadas, viabilidade do lote e queda de postura, as aves que receberam alimentação à base de casca de soja tiveram desempenho semelhante ao das aves em jejum, quando comparadas aos animais que receberam os demais alimentos. O uso de sorgo com alto tanino reduziu de forma notável a mortalidade entre as aves, entretanto não tem o efeito desejado sobre a redução na taxa de postura. Com níveis de postura considerados de 12%, as aves submetidas aos protocolos alternativos atingiram este nível em aproximadamente seis dias após o início da muda forçada. Assim, é possível substituir o método convencional de muda (jejum prolongado), por métodos alternativos que não são tão degradantes fisiologicamente e nem no bem estar animal para as poedeiras comerciais no fim do primeiro ciclo produtivo.

La fermentation en milieu solide est un bioprocédé pouvant éventuellement être utilisé comme technologie de rupture pour diminuer le coût des biocatalyseurs utilisés dans la conversion de biomasse lignocellulosique comme le son de blé. La première partie de ces travaux de recherche a donc étudié le potentiel de cette technologie par rapport à celle de fermentation en milieu submergé lors d'une comparaison en application. Plusieurs tests de saccharification ont ainsi été réalisés sur différentes matières premières (cellulose, son de blé) et ont permis de montrer l'avantage différentiateur des biocatalyseurs produits par fermentation en milieu solide. Ensuite, la deuxième partie de ces travaux de recherche a porté sur l'étude des facteurs de la récalcitrance du son de blé à l'hydrolyse enzymatique. Deux principaux facteurs ont ainsi pu être démontrés : un facteur physique, lié à l'accessibilité des biocatalyseurs aux polysaccharides, et un facteur biochimique, lié à l'absence ou à la faible présence de certaines activités enzymatiques (féruloyl estérase,…) dans le complexe enzymatique de Trichoderma reesei Rut-C30. Cette étude a également permis d'identifier l'origine des différentes fractions glucidiques hydrolysées et de déterminer le potentiel glucidique actuellement hydrolysable à partir de cette biomasse. Enfin, la dernière partie de ces travaux de recherche a été consacrée à l'étude pratique d'un concept innovant de procédé permettant de favoriser la conversion des polysaccharides contenus dans le son de blé. Une levée de la barrière physique au transfert de masse et par conséquent une validation de ce concept a finalement pu être réalisée. / Solid-state fermentation is a bioprocess that can optionally be used as disruptive technology to reduce the cost of biocatalysts used in the lignocellulosic biomass conversion like wheat bran. The first part of this research has explored the potential of this technology compared to submerged fermentation in an application comparison. Several saccharification tests have thus been carried on different feedstocks (cellulose, wheat bran) and have shown the differentiator advantage of biocatalysts produced by solid state fermentation. Then, the second part of this research has investigated the recalcitrance factors of wheat bran to enzymatic hydrolysis. Two main factors have thus been demonstrated: a physical factor, related to the accessibility of biocatalysts to the polysaccharides, and a biochemical factor, related to the absence or the low presence of some enzymatic activities (feruloyl esterase, ...) in the enzymatic complex of Trichoderma reesei Rut-C30. This study has also identified the origin of the various carbohydrate moieties hydrolyzed and has determined the carbohydrate potential currently releasable from this biomass. Finally, the last part of this research has been devoted to the practical study of an innovative concept of process to promote the conversion of polysaccharides in wheat bran. A removal of the physical barrier to mass transfer and therefore a validation of this concept has finally been achieved.

With the advent of industrialization and food processing techniques the sizes of the cereal bran have been drastically reduced. In my thesis, I have tested the effect, if any, of wheat bran and maize bran particle size, in vitro, on the gut microbiota community structure by 16S rRNA sequencing and their function, by Short chain fatty acids (acetate, propionate, butyrate) production. In turn, we also linked the microbiota and SCFA differences to different chemical composition amongst variously sized fractions of wheat and maize bran.

Wheat bran is a promising material containing a wide range of useful components, including proteins. In addition, it is produced in significant volumes. Currently, wheat bran is used for the production of energy by combustion and for feed purposes. Gradually, new methods of valorization of this material are being sought. One of the possibilities of using wheat bran is the isolation of proteins, hydrolysis, and separation of selected amino acids. This diploma thesis deals with this issue, it is focused on the recovery of arginine and leucine from a protein isolate. Proteins were extracted from wheat bran by changing the pH. Thanks to the subsequent lyophilization a protein isolate was gained. Prior to hydrolysis of the resulting isolate, a stability test of arginine and leucine amino acid standards was first performed, to which various hydrolysis methods were applied. Acid hydrolysis using a mineralizer, which was applied to the protein isolate, was proved to be the most effective. This was followed by the derivatization of the hydrolysates with OPA and analysis of the resulting hydrolysates by high-performance liquid chromatography with UV-VIS detection. Then, suitable adsorption and desorption conditions were optimized. It was found that the time dependence does not affect the amount of adsorbed material on the sorbent. Therefore, an application time of 15 minutes was chosen. While optimizing the amount of used standard, it was found that the optimal weight was 0.25 g of sorbent. The selected conditions were applied to the protein hydrolyzate. Two fractions were obtained by the separation of selected amino acids due to the change in the pH of the citrate buffer. After the application of this procedure, 0.26 g of arginine and 0.82 g of leucine were obtained from one kilogram after evaporation. From evaporation two, 1.01 g of arginine and 0.25 g of leucine were obtained after evaporation.

This master thesis deals with an optimization of processes of isolation of ferulic acid from wheat bran. Process of isolation based on alkaline hydrolysis from the substance and its adsorption was tested. In the theoretical part were described wheat bran, adsorption proces and used methods. For adsorption were tested five types of adsorbents. Especially these adsorbents: activation carbon (2,53 ± 1,16 mg.l-1), Amberlyst A-21 (105,73 ± 11,87 mg.l-1, Amberlit XAD-16 (241,55 ± 10,42 mg.l-1), Amberlit IRA-900Cl (5,90 ± 0,68 mg.l-1) and Amberlit IRA-96 (189,16 ± 6,49 mg.l-1). As the most efficient adsorbent was determine Amberlit XAD-16. The whole process has underwent detailed optimization in order to maximize the purity of the final product. The isolate was characterized by HPLC and FTIR techniques for ferulic acid and related phenolic acids. Based on FTIR analysis was discovered that the isolate was contamined by proteins. A purification procedure based on deproteination of the raw material before the hydrolysis itself was proposed. As the ultimate solution that eliminated the presence of proteins in the isolate was determine ultrafiltration with capture of molecules with Mw > 10 KDa. Ferulic acid yield from one kilo of wheat bran was 1,00 ± 0,22 g.

Le son et la paille de blé, riches en hémicelluloses, sont deux co-produits de la récolte de blé, abondants et renouvelables, mais qui restent à mieux valoriser. Dans le but d'extraire ces hémicelluloses, possédant plusieurs propriétés intéressantes (filmogènes, épaississantes, émulsifiantes, stabilisantes…), un procédé de fractionnement a été élaboré. Ce procédé consiste, après extraction alcaline, en la purification des extraits hémicellulosiques obtenus. Deux techniques ont été appliquées : l'ultrafiltration et la chromatographie sur résine échangeuse d'anions. L'ultrafiltration a permis de concentrer les extraits d'hémicelluloses et de les purifier en éliminant dans le perméat la plupart des molécules contaminantes, essentiellement les sucres libres et les sels minéraux. Les principales limitations de cette étape étaient la viscosité des extraits et les phénomènes de polarisation de concentration et de colmatage des membranes. La percolation sur résine, quant à elle, a permis de décolorer les extraits et de produire des poudres d'hémicelluloses plus claires en fixant certaines molécules colorées telles que les molécules possédant des groupements phénoliques. La combinaison des deux techniques a permis de produire des hémicelluloses pures à 60%. L'extrapolation du procédé à l'échelle pilote par l'utilisation d'un extrudeur bi-vis a permis d'obtenir des poudres d'hémicelluloses pures à 40%. / Wheat bran and wheat straw are two by-products abundant and renewable, rich in hemicelluloses, but still not well valued. In order to extract these hemicelluloses characterized by their several interesting properties (film-forming, thickening, emulsifying, stabilizing…), a fractionation process was developed. This process consisted, after alkaline extraction, to purify the hemicellulosic extracts obtained. Two techniques were used: ultrafiltration and chromatography on anion exchange resin. The ultrafiltration allowed to concentrate the extracts and to purify them by removing in the permeate, the contaminating molecules, mostly free sugars and minerals. The main limiting factors of this stage were the extracts viscosity and the fouling of the membranes. The percolation on the resin discoloured the extracts and allowed to produce hemicellulosic powders with lighter colours and that by capturing the coloured compounds such as molecules with phenolic groups. The combination of the two techniques allowed the production of purified hemicelluloses; the purity was about 60%. The extrapolation of the process at a pilot scale using a twin-screw extruder allowed to obtain hemicelluloses with a purity of 40%.