Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2007. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-09-25T19:15:56Z No. of bitstreams: 1 dissertao vivian feddern.pdf: 798840 bytes, checksum: fb6b9cb9996dbbe1c8dcf944da2944b5 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2012-11-06T18:24:30Z (GMT) No. of bitstreams: 1 dissertao vivian feddern.pdf: 798840 bytes, checksum: fb6b9cb9996dbbe1c8dcf944da2944b5 (MD5) / Made available in DSpace on 2012-11-06T18:24:30Z (GMT). No. of bitstreams: 1 dissertao vivian feddern.pdf: 798840 bytes, checksum: fb6b9cb9996dbbe1c8dcf944da2944b5 (MD5) Previous issue date: 2007 / As misturas à base de farelo de cereais, popularmente denominadas de multimisturas, vêm se destacando no combate a desnutrição infantil em comunidades de baixa renda, por serem um suplemento de baixo custo e por aportarem nutrientes como minerais, vitaminas e proteínas. Este trabalho objetivou avaliar a biodisponibilização de nutrientes em multimisturas através da alteração da composição e de um processo fermentativo. Para tal, foi realizada a caracterização físico-química e nutricional dos farelos de arroz fermentado e não fermentado e foram também elaboradas, caracterizadas físico-química e nutricionalmente e avaliadas biologicamente oito multimisturas que diferiram quanto ao tipo de farelo (trigo ou arroz); presença ou ausência de pó de folha de mandioca; submetidos ou não a processo fermentativo em estado sólido com Saccharomyces cerevisiae durante 6h a 30ºC. As multimisturas foram peletizadas constituindo as dietas que foram administradas em ratas da cepa Wistar/UFPEL, avaliadas pelo coeficiente de eficiência alimentar, razão de eficiência protéica, razão de eficiência líquida protéica e digestibilidades in vivo aparente e verdadeira. Foram realizados ainda testes bioquímicos como determinação de glicose sanguínea e cálcio plasmático nas ratas. Os resultados permitiram concluir que a fermentação do farelo de arroz ocasionou uma diminuição nos valores de pH, metionina disponível e carboidratos, proporcionando um aumento da acidez, dos açúcares redutores, cinzas e fibras. Os teores de cálcio, proteína e lipídios não foram alterados. As multimisturas com farelo de arroz apresentaram médias dos teores de lipídios (18,1%), cinzas (14,1%), fibras (7,8%), acidez (3,1%), digestibilidade in vitro (80,8%) mais elevadas do que as multimisturas com farelo de trigo, as quais, por sua vez, apresentaram teores de proteínas (14,5%), carboidratos (68,9%) e pH (7,8) maiores que as com farelo de arroz. A fermentação, em algumas multimisturas, ocasionou aumento nos conteúdos de proteínas, minerais, fibras e acidez, porém uma diminuição dos carboidratos, metionina disponível e pH. Com relação aos efeitos biológicos, a fermentação ocasionou aumento no coeficiente de eficácia alimentar na maioria das multimisturas, não influenciando o quociente de eficiência protéica, o quociente de eficiência líquida protéica, a digestibilidade in vivo ou in vitro, a glicemia e o cálcio plasmático. A presença da folha de mandioca não influenciou na composição físico-química das multimisturas, mas tendeu a apresentar melhores coeficientes de eficácia alimentar que as demais multimisturas. As multimisturas contendo farelo de trigo apresentaram valores de digestibilidade in vivo superiores às multimisturas com farelo de arroz. / The mixtures based on cereal brans, popularly denominated “multimisturas”, are standing out to combat infantile malnutrition in communities of low income, by being a low cost supplement and for containing nutrients, such as minerals, vitamins and proteins. In virtue of existence controversies on the real nutritional value of the “multimisturas”, this work aimed at evaluating the bioavailability of nutrients in “multimisturas” by altering the formulation and a fermentative process. Therefore, it was made the physical-chemical and nutritional characterization of fermented and not fermented rice bran, and it was also elaborated, characterized physical-chemical and nutritionally and biologically evaluated eight “multimisturas”, which differed from each other by the source of bran (rice or wheat bran), presence or not of cassava leaf powder and being or not submitted to a solid-state fermentation process with Saccharomyces cerevisiae during 6h at 30ºC. The “multimisturas” were manually made in pellets, constituting the diets, which were administered in female Wistar/UFPEL rats. The diets were evaluated by Food Efficiency Ratio (FER), Net Protein Ratio (NPR), Protein Efficiency Ratio (PER) and apparent and true in vivo digestibility. Biochemical tests as the blood glucose determination and plasmatic calcium in female Wistar/UFPEL rats were also realized. The results allowed concluding that the fermentation of the rice bran caused a decrease on pH, available methionine and carbohydrates, providing an increase of the acidity, reducing sugars, ashes and fibers. Calcium, protein and lipids contents were not altered. The “multimisturas” with rice bran presented averages of lipids (18,1%), ashes (14,1%), fibers (7,8%), acidity (3,1%), in vitro availability (80,8%) higher than the “multimisturas” with wheat bran, which presented proteins (14,5%), carbohydrates (68,9%) and pH (7,8) values higher than the “multimisturas” with rice bran. In some “multimisturas”, the fermentation caused an increase in proteins, fibers, acidity, but a decrease in carbohydrates, available methionine and pH. With relationship to the biological effects, the fermentation caused a FER increase in most of the “multimisturas”, not influencing PER, NPR, in vivo or in vitro digestibility, glycemia and plasmatic calcium. The presence of cassava leaf, didn't influence the physical-chemical composition of multimisturas, but it tended to present better FER that the other ones. The “multimisturas” containing wheat bran presented higher values of in vivo digestibility than those with rice bran.

Afin d’approfondir les connaissances sur les liens entre la structure et les propriétés nutritionnelles de pâtes alimentaires, des pâtes de structures contrastées ont été produites en modifiant la formulation et/ou le procédé de fabrication. Leur structure a été caractérisée aux différentes échelles, puis les caractéristiques définies ont été reliées à la digestibilité des protéines et de l’amidon. Le remplacement partiel ou total de la semoule de blé dur par des farines de légumineuses dans la fabrication des pâtes a engendré des changements structuraux à plusieurs niveaux. Un affaiblissement marqué de la structure du réseau protéique proportionnel à la quantité de légumineuses incorporées a notamment été observé, conduisant à une amélioration de la digestibilité in-vitro des protéines. La digestibilité in-vitro de l’amidon était en revanche maintenue à son faible niveau voir même réduite. L’application de différentes températures de séchage a amplifié les modifications de la structure des pâtes enrichies en légumineuses. Ces différences s’atténuaient toutefois après cuisson, n’engendrant de fait aucune modification marquée de la digestibilité in-vitro des protéines entre une pâte cuite préalablement séchée à basse ou à très haute température. Les teneurs en facteurs antinutritionnels étaient réduites par le procédé de fabrication et de cuisson des pâtes. A quantité égale de protéines consommées, l’étude in-vivo a révélé une augmentation de la croissance et de l’efficacité azotée chez les rats nourris avec les pâtes mixtes blé/fèverole (65/35) par comparaison aux rats nourris aux pâtes 100% blé. L’assemblage blé/fèverole constituait un mélange protéique efficace pour la croissance des rats jeunes, probablement du fait de son profil équilibré en acides aminés, et de la structure affaiblie du réseau protéique. Par ailleurs, les différentes températures de séchage appliquées aux pâtes n’ont pas engendré de différence au niveau de la rétention azotée in-vivo. Les spécialités pastières développées au cours de ce travail de thèse sont jusqu’à trois fois plus riches en protéines et mieux équilibrées en acides aminés, comparativement à une pâte alimentaire classique. Ces spécialités pastières sont aussi appréciées que leurs homologues qui se vendent sur le marché. En outre, la recette mixte blé/légumineuses peut être adaptée à tout consommateur souhaitant diversifier ses apports en protéines, mais également à certaines populations spécifiques, notamment aux personnes âgées. La recette 100% légumineuses peut concerner les personnes intolérantes au gluten. Ces spécialités pastières pourraient de ce fait, trouver une large application à l’échelle industrielle. / In order to reinforce our knowledge about the links between structural and nutritional properties of pasta, pasta with contrasting structures were produced by modifying the formulation and/or the manufacturing process. Pasta structure was then characterized using a multiscale approach and linked to the digestibility of protein and starch fractions. The modification of pasta formulation by partial or total substitution of durum wheat semolina by legume flours changed pasta structure at various scales. A marked weakening in the structure of pasta protein network proportional to the level of legume protein incorporated was observed and related to an improvement of the in-vitro digestibility of pasta proteins. Interestingly the in-vitro starch digestibility was maintained at its low level or even reduced in mixed pasta. Changing pasta drying temperature amplified changes in the pasta structure. These differences, however, were reduced after cooking pasta resulting in unchanged in-vitro protein digestibility between cooked pasta dried at low or very high temperature. Anti-nutritional factors were also reduced by the manufacturing and cooking steps. In-vivo study revealed a better growth and nitrogen efficiency in rats consuming the same quantity of proteins from wheat/faba (65/35) mixed pasta in comparison with animals fed with 100% wheat pasta. This was probably related to the better amino acid balance, and to the weakened protein network in mixed pasta. The change in drying temperatures did not allow modifying protein retention. Pasta developed in this thesis are up to three fold richer in proteins than traditional wheat pasta, and more balanced in essential amino acids. Produced pasta are appreciated by the consumer as well as their counterparts found on the marked. Mixed wheat/legume may be adapted to the elderly people, whereas 100% legume pasta may be consumed by gluten intolerant subjects. Produced pasta may therefore find wide application at the industrial scale.

There has been increased interest in utilizing switchgrass (Panicum virgatum) as biomass. There are several challenges to developing this industry, and these have led to the potential use of switchgrass as hay for feeding beef cattle in Kentucky. The effect of increasing maturity on crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and nutritive values of switchgrass hay has been well documented, but few in vivo intake and digestibility trials have been conducted to assess this effect on animal performance when feeding beef cattle. Two in vivo intake and digestibility trials were conducted in 2011 in which Angus x Hereford beef steers (200-265 kg) were fed Alamo and Cave-in-Rock switchgrass harvested as late vegetative, boot, and early flowering hay. The objectives of these trials was to evaluate the effect of increasing maturity on apparent dry matter intake (DMI), digestible dry matter intake (DDMI), and dry matter digestibility (DMD); and to discuss potential challenges that producers might face if incorporating switchgrass hay into their forage program for feeding beef cattle. Observed decreases in nutritive value, DMI, DDMI, and DMD indicate that producers should harvest Alamo and Cave-in-Rock switchgrass before it reaches the boot stage of maturity.

Made available in DSpace on 2016-12-08T16:24:11Z (GMT). No. of bitstreams: 1 PGCA12MA090.pdf: 189691 bytes, checksum: 4e1b76e5649f41b702f0b221276e653e (MD5) Previous issue date: 2012-03-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this work was to assess the effect of inclusion of Arachis pintoi hay in different levels on feeding value of grass-dwarf elephant grass (Pennisetum purpureum Shum, genotype EMBRAPA/CNPGL 92-198-7) diets. The Arachis pintoi hay was included in 0%, 33%, 66% e 100% of diet proportion. Eight crossbred lambs Texel x Suffolk, males, castrated, with 41 ± 4 kg weight were maintain in metabolic cage for four period (16 days each). Four of these animals have duodenal cannula. The experimental desing was a double latin square 4x4. The diets of each treatment were offered ad libitum, adjusting the amount each day up to 30% consumption of the day before. The organic matter (OM) intake increased (slope = 0.07 g/kg PV0.75) with the inclusion of legume, despite a decreased of OM truly digestibility (slope = 0.06%). The nitrogen intake and daily retention (slope = 0.18 and 0.11 g/day, respectively) increased linearly with the inclusion of legume. However, due to decreased on efficiency of microbial growth (g of microbial nitrogen/kg digestible OM), the microbial protein supply was similar between treatments. The Arachis pintoi inclusion, in grass-dwarf elephant grass diets, improve the feeding value due increases in voluntary intake and nitrogen daily retention, regardless of reductions on OM digestibility / O objetivo deste trabalho foi avaliar o efeito dos diferentes níveis de inclusão do feno de amendoim forrageiro (Arachis pintoi) sobre o valor alimentar em dietas a base de capimelefante anão (Pennisetum purpureum Shum, genótipo EMBRAPA/CNPGL 92-198-7). O feno de Arachis pintoi foi incluído nas proporções de 0%, 33%, 66% e 100% da dieta. Os animais utilizados foram oito ovinos mestiços Suffolk × Texel, machos, castrados, pesando em média 41 ± 4 kg, os quais foram mantidos em gaiolas metabólicas durante quatro períodos experimentais (16 dias cada). Quatro desses animais eram dotados de cânula duodenal. O delineamento experimental foi em duplo quadrado latino 4×4. As dietas de cada tratamento foram fornecidas ad libitum, ajustando-se diariamente a quantidade para 30% acima do consumo do dia anterior. O consumo de matéria orgânica (MO) verdadeiramente digestível (coeficiente linear = 0,07 g/kg PV0,75) respondeu positivamente à inclusão da leguminosa embora a digestibilidade verdadeira da MO tenha diminuído (coeficiente linear = 0,06%). O consumo e a retenção diária de nitrogênio (coeficiente linear = 0,18 e 0,11 g/dia, respectivamente) aumentaram linearmente com a inclusão da leguminosa. Contudo, em função da diminuição da eficiência de crescimento microbiano (g de nitrogênio microbiano/kg de MO digestível), a síntese de proteína microbiana não variou com a inclusão da leguminosa na dieta. A inclusão do Arachis pintoi em dietas a base de capim-elefante anão eleva o valor alimentar da dieta devido ao aumento do consumo voluntário e da retenção diária de nitrogênio, independente de reduções na digestibilidade da MO

Cette étude a été menée dans le but d’explorer les nouvelles sources de protéines à valeur nutraceutique. Les graines de Ricinodendron heudelotii (Bail. Pierre ex Pax) et de Tetracarpidium conophorum (Müll. Arg) ont d’abord été cuites dans de l’eau bouillante pendant 90 et 30 min qui sont respectivement leurs temps optimums de cuisson. Après délipidation et tamisage des tourteaux, la fraction 400 - 500 µm s’est révélée la plus représentative avec plus de 70 % et riche en azote protéique (6–7% MS). Les concentrats et les isolats protéiques ont été préparés à partir des tourteaux respectivement dans l’eau distillée à pH 4,5 et dans une solution de NaOH à 0,2 % (R. heudelotii), une solution de NaCl 0,6 M (T. conophorum) à pH 11. Ces concentrats (65 – 75 % MS de protéines) et ces isolats protéiques (81 – 92 % MS de protéines) ont une composition physico-chimique différente (P < 0,05) de celle des tourteaux. Pour les deux Euphorbiacées, les capacités de rétention d’eau (367 – 467 g / 100 g d’échantillon), de rétention d’huile (256 – 410 g / 100 g d’échantillon) et moussante (68 – 71 %) sont maximales dans les isolats protéiques tandis que les capacités gélifiante (6 – 14 %) et émulsifiante (63 – 87 %) le sont dans les concentrats protéiques. Les teneurs en acides aminés essentiels des tourteaux de R. heudelotii et de T. conophorum sont comparables à celle de la protéine de référence. L’étude de la digestibilité enzymatique in vitro a montré que l’azote libéré après 6 h est supérieur à 90 % dans les concentrats et les isolats protéiques. La digestibilité protéique in vivo indique que le gain de poids des rats mâles âgés de 21 ± 3 jours durant 15 jours d’expérimentation ainsi que les paramètres de rétention azotée sont plus importants avec les régimes à base de l’aliment de référence (caséine) et du tourteau de T. conophorum. Les valeurs corrigées des paramètres de digestibilité par l’indice chimique des acides aminés laissent apparaître que le tourteau de T. conophorum renferme les protéines de très bonne qualité nutritionnelle, autant que la caséine / This study was conducted in order to look for alternative sources of proteins having nutraceutic value. The grains of Ricinodendron heudelotii (Bail.) and Tetracarpidium conophorum (Müll. Arg) were first cooked in boiled water at their optimal cooking time for 90 and 30 min respectively. After defating, sieving of the defatted cakes showed that samples with a granulometry of 400 - 500 µm were most representative (more than 70%), containing more proteic nitrogen (6–7 %). Protein concentrates and protein isolates were prepared from defatted cakes respectively in distilled water at pH 4.5 and in NaOH 0.2% (R. heudelotii) and NaCl 0.6M (T. conophorum) at pH 11. Physico-chemical properties of protein concentrates (65 – 75 % of proteins) and protein isolates (81–92 % of proteins) were different from those of the defatted cakes. Water holding (367 – 467 g / 100 g of sample), oil holding (256 – 410 g / 100 g of sample) and foaming capacities (68 – 71 %) were highest with protein isolates whereas gelling (6 – 14 %) and emulsion capacities (63 – 87 %) were highest with concentrates. The amounts of essential amino acids in both defatted flours were comparable to the value in FAO / WHO (2007) scoring pattern. Nitrogen liberated after 6 h of enzymatic digestibility was more than 90 % both in the proteins concentrates and isolates. In vivo studies carried out on 21 ± 3 days old Sprague Dawley male rats for 15 days showed that gain of weight and nitrogen retention parameters were higher for rats that consumed casein and T. conophorum defatted cake. Corrected values of nitrogen digestibility of the analysed samples showed that T. conophorum defatted cake contains protein source with good nutritional quality