Title of thesis: Polymeric stabilizers maintaining the saturation solubility of itraconazole nanocrystals after dissolution process Author: Jana Kubačková Department: Pharmaceutical Technology Supervisor: PharmDr. Ondřej Holas, Ph.D. Specialized supervisor: Assoc. Prof. Leena Peltonen, Ph.D. The increase of bioavailability of poorly water soluble drugs is still an issue. One of the techniques improving aqueous drug substance solubility, and consequently enhancing bioavailability, is formation of nanoparticles. However, the bioavailability is determined by the concentration of the dissolved drug achieved at the time of absorption. This fact emphasizes the importance of the maintenance of the high solubility until the absorption area is reached. Sufficiently stabilised nanocrystalline drugs offer a solution to this problem. In this thesis, the solid nanoparticle formations of an antifungal agent itraconazole (ITZ) are presented. Wet milling was employed to create the nanosuspension stabilised by binary mixture of stabilisers or by a single stabiliser. An aggregation inhibitor Poloxamer 407 (F127) in the combination with a polymeric precipitation inhibitor hydroxypropyl methylcellulose (HPMC) or polyvinyl pyrrolidone (PVP) at different ratios, or a single precipitation inhibitor, were utilised. The...

Pearl millet is a staple food in Namibia. It is milled into flour by traditional and industrial dry milling processes. This research was conducted to help determine how to improve the nutritional value and acceptability of pearl millet. The traditional milling process involves a lactic acid fermentation step which lowers the pH of kernels. The effects of the traditional Namibian and industrial “dry milling” processes on the physical and nutritional composition of pearl millet grain were compared. Additionally, the effect of steeping three different Namibian pearl millet varieties (Kangara, Kantana and Okashana 2) in lactic acid and water on the colour and the phenolic content of the flour were determined. Regarding comparing the milling processes, variety Kangara was conditioned and decorticated traditionally with a pestle and mortar and industrially with an abrasive decorticator. The traditional decorticated grain was steeped and sun dried for 24 h before hammer milling, whereas the industrially decorticated grain was roller milled. Tristimulus colorimetry and proximate analyses were conducted on the samples. Concerning acid steeping, kernels were steeped in a pH 3.5 solution and in water as a control. Colour, total polyphenol and c-glycosyl flavone contents were determined. The determination of cglycosylflavone content was particularly important because these compounds are considered goitrogenic. The traditionally milled flour was lighter in colour than industrial milled flour. However, it was significantly lower in protein, ash and c-glycosyl flavone contents in comparison to industrial milled flour. This was due to the removal of more pericarp and germ in the traditional process. The industrial dry milling process therefore produces flour with a higher nutrient content in terms of protein, fat and minerals. However, the traditional Namibian milling process makes the colour of the pearl millet flour lighter, which is probably the reason that it is more acceptable to consumers. Kernels steeped in a lactic acid solution were lighter in colour than those steeped in water. Irrespective of the steeping media, the total polyphenol content was significantly lower in steeped kernels compared to those unsteeped. A similar trend was observed for the cglycosyl flavone content. This indicates that some of these compounds may have leached out during steeping. For all varieties, kernels steeped in lactic acid had a significantly higher total polyphenol content than those in water, probably due to the dissociation of metal-polyphenol complexes in the acidic medium whereby these polyphenols became free and available for measurement. Thus, steeping in a lactic acid solution can lead to better colour improvement of kernels compared to steeping in water. Thus, lactic acid steeping can improve the sensory quality of pearl millet products. An industrial process can thus be designed to include tempering the grain with food grade lactic acid to produce sour taste and leach out the colour pigments, particularly the cglycosyl flavones hence lightening the colour of the industrial milled flour. This produces a product with high nutritional content, lighter in colour and has the sour taste that consumers find appealing. Copyright 2007, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Barrion, SC 2007, Pearl millet milling : comparison between traditional Namibian fermentation - semi-wet milling and dry milling, MSc(Agric) dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-01282009-132241 / > E1209/gm / Dissertation (MSc(Agric))--University of Pretoria, 2009. / Food Science / unrestricted

De acordo com a Organização Mundial de Saúde, existem atualmente 17 doenças tropicais negligenciadas prevalentes em 149 países, afetando aproximadamente um bilhão de pessoas, a nível global. A leishmaniose, problema de saúde prevalente nos países em desenvolvimento, é endêmica em aproximadamente 98 países e territórios, com 350 milhões de pessoas em risco e 12 milhões de casos de infecção no mundo. A transmissão da doença ocorre pela picada de flebotomíneos fêmeas infectadas. Essa doença apresenta três formas principais: leishmaniose cutânea (LC), leishmaniose mucocutânea (LMC) e leishmaniose visceral (LV). Enquanto a leishmaniose cutânea é a forma mais comum da doença, a leishmaniose visceral é a mais grave e pode ser fatal se não for tratada. Em 2016, o Brasil reportou 3.626 e 12.690 casos de LC e LV, respectivamente. O candidato a fármaco hidroximetilnitrofural (NFOH) mostrou atividade contra o parasita da doença de chagas e da leishmaniose. Embora o NFOH seja promissor para o tratamento da leishmaniose, esse possui baixa solubilidade em água. A nanotecnologia tem sido empregada como plataforma para o desenvolvimento de formas farmacêuticas inovadoras com maior eficácia e segurança. A redução do tamanho de partículas em escala nanométrica permite aumentar a biodisponibilidade oral de fármacos pouco solúveis em água. Os nanocristais apresentam vantagens, tais como, o aumento da solubilidade de saturação e da velocidade de dissolução, decorrentes do aumento da área superficial da partícula. Além disso, esses apresentam maior adesividade às membranas biológicas, membrana celular e superfície do trato gastrointestinal. No presente trabalho utilizou-se a moagem por via úmida em escala reduzida para a obtenção dos nanocristais de NFOH. Diferentes tensoativos foram avaliados empregando o método selecionado, os tensoativos poloxamer 188 e poloxamer 407 foram os que favoreceram a redução do tamanho das partículas. Tal característica foi observada na caracterização físico-química das nanosuspensões de NFOH. A utilização desse método permitiu a obtenção de nanocristais de NFOH, com diâmetro hidrodinâmico médio (DHM) de 184,8 ± 0,5 a 325,9 ± 2,2 nm, índice de polidispersão (IP) de 0,21 ± 0,01 a 0,57 ± 0,01 e DHM de 191,3 ± 2,1 a 326,8 ± 4,6 nm e IP de 0,21 ± 0,01 a 0,50 ± 0,01, respectivamente para o poloxamer 188 e 407. O uso de ambos os tensoativos resultaram em distribuição monomodal de tamanho das partículas. As formulações foram obtidas por meio de planejamento fatorial completo e experimentos por superfície de resposta tendo como variáreis independentes as concentrações de NFOH, dos tensoativos e o tempo de moagem. A resposta, DHM, foi determinada utilizando espalhamento de luz dinâmica (DLS). Adicionalmente, as avaliações empregando calorimetria exploratória diferencial (DSC) e difração de raio X (DRX) revelaram que não houve interação entre o fármaco e os excipientes, assim como, não foi observada alteração na estrutura cristalina do NFOH. A microscopia eletrônica de varredura demonstrou a morfologia característica do estado cristalino. Além disso, a preparação liofilizada apresentou instabilidade após armazenamento por três meses a temperatura de 25 e 4 °C. / According to the World Health Organization, there are currently 17 neglected tropical diseases prevalent in 149 countries, affecting approximately one billion people globally. Leishmaniasis, a health problem prevalent in developing countries, is endemic in approximately 98 countries and territories, with 350 million people at risk and 12 million cases of infection worldwide. The transmission of the disease occurs by the bite of infected female sandflies. This disease has three main forms: cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL) and visceral leishmaniasis (VL). While cutaneous leishmaniasis is the most usual form of the disease, visceral leishmaniasis is the most serious and can be fatal if left untreated. In 2016, Brazil reported 3.626 and 12.690 cases of LC and LV, respectively. The drug candidate for hydroxymethylnitrofurazone (NFOH) showed activity against the parasite of chagas disease and leishmaniasis. Although NFOH is promising for the treatment of leishmaniasis, it has low solubility in water. Nanotechnology has been used as a platform for the development of innovative pharmaceutical forms with greater effectiveness and safety. Particle size reduction on the nanoscale enables the oral bioavailability of poorly water-soluble drugs to be increased. Nanotechnology has been used as a platform for the development of innovative pharmaceutical forms, improving effectiveness and safety. Particle size reduction on the nanoscale enables the oral bioavailability of poorly water-soluble drugs to be increased. Nanocrystals have advantages such as increased saturation solubility and dissolution rate due to the increase in the surface area of the particle. In addition, this present greater adhesiveness to the biological membranes, cell membrane and surface of the gastrointestinal tract. In the present work, wet scale milling was used to obtain NFOH nanocrystals. Different surfactants were evaluated using the selected method, poloxamer 188 and poloxamer 407 surfactants favored the reduction of particle size. This characteristic was observed in the physical-chemical characterization of NFOH nanosuspensions. The use of NFOH nanocrystals with a mean hydrodynamic diameter (DHM) of 184.8 ± 0.5 to 325.9 ± 2.2 nm, polydispersity index (IP) of 0.21 ± 0, 01 to 0.57 ± 0.01 for poloxamer 188 and DHM of 191.3 ± 2.1 at 326.8 ± 4.6 nm and IP of 0.21 ± 0.01 at 0.50 ± 0.01 for poloxamer 407, both with monomodal size distribution. The formulations were obtained by means of complete factorial planning and surface response experiments having as independent variables the concentrations of NFOH, surfactants and milling time. The response, DHM, was determined using dynamic light scattering (DLS). In addition, evaluations using differential scanning calorimetry (DSC) and X-ray diffraction (DRX) revealed that there was no change in the crystal structure of NFOH and interaction between the drug and the excipients. Scanning electron microscopy demonstrated the characteristic morphology of the crystalline state. In addition, the lyophilized preparation was instable after storage for three months at 25 and 4 ° C.

Le présent travail sinscrit dans le cadre de la recherche dune meilleure compréhension de l'incidence des traitements de séchage du maïs sur la séparation des fractions amylacées et protéiques ainsi que sur les propriétés techno-fonctionnelles de ces fractions. Létude de linfluence des températures de séchage sur les propriétés techno-fonctionnelles du maïs a montré que les températures élevées du séchage provoquent une insolubilisation des protéines salino-solubles et de la zéine, rendant difficile la séparation des protéines et des amidons au fractionnement du maïs par voie humide. Lévolution des rendements dextraction de lamidon et des indices de solubilité des protéines en fonction des températures de séchage a été ajustée dune façon satisfaisante à laide dun modèle sigmoïdal à deux asymptotes. Ce modèle a lavantage dinclure dans sa structure mathématique, des informations sur la dynamique interne de la variation des paramètres suivis. Les corrélations entre les indices de solubilité de différentes familles de protéines du maïs et laptitude au fractionnement des grains permettent de préconiser lutilisation des indices de solubilité des protéines salino-solubles totales comme paramètre dévaluation de la sévérité de traitement thermique subis par les grains au régard des rendements dextraction damidons observés. Les températures élevées de séchage confèrent aux granules damidon une rigidité thermique, qui se manifeste par laugmentation de leurs températures de début de gélatinisation, par la diminution de leur capacité de gonflement et de rétention deau, ainsi que par la diminution de leur solubilité à la gélatinisation. Cette rigidité résulte des restructurations internes aux granules et est la principale cause de laltération du comportement des amidons pendant leur cuisson en milieu aqueux et de la modification des propriétés rhéologiques et texturales des gels quils forment.

Resumo: O presente estudo objetivou determinar as características químicas e as frações componentes de fibras de milho, extraídas em laboratório (FL) e em processo industrial (FI) e elaborar barras de cereais adicionadas desta fibra com o propósito de agregar valor ao co-produto. A caracterização química foi realizada através de análises de umidade, cinzas, proteína, lipídeos, carboidratos disponíveis, Fibra em Detergente Neutro (FDN), Fibra em Detergente Ácido (FDA), hemicelulose, celulose, lignina, fibra alimentar total, insolúvel e solúvel. Os produtos analisados diferiram significativamente ao nível de 5% quanto às frações de fibra alimentar (FDN e FDA). FL deteve o maior percentual de lignina. O percentual de hemicelulose foi maior que o de celulose e lignina nos dois tipos, havendo predomínio da fração insolúvel da fibra. Análises microbiológicas da FI mostraram que o produto encontra-se dentro dos limites permitidos pela legislação. Foram produzidas barras de cereais adicionadas de 10, 20 e 30% de fibra de milho industrial (FM) com e sem forneamento (C/ e S/FN), e estas submetidas à analises físico-químicas, microbiológicas e sensorial. As barras com 20 e 30% FM S/FN foram as mais densas (0,7 g/cm3) e a que apresentou maior volume específico foi com 10% FM C/FN (1,7 cm3/g). Com o aumento dos percentuais de fibra observou-se a diminuição do volume das barras. A atividade de água ficou na faixa de 0,5 e o pH, variou entre 4,7 e 5,0, mostrando baixa acidez dos produtos. A luminosidade (L*) ficou entre 42,8 e 51,0, aumentando conforme o aumento do percentual de fibra. Quanto às cromaticidades, as amostras apresentaram valores positivos de a* e b*. A tonalidade cromática (H*) variou de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The current study focused on determining the chemical characteristics and the fractional components of corn fibers, extracted in laboratory (FL) and industrial processing (FI) and producing cereal bars made from corn fiber intended to add value to the co-product. Chemical characterization was performed through the analyses of humidity, ashes, protein, lipids, available carbohydrates, neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, cellulose, lignin, total dietary fiber, insoluble and soluble. The products analyzed were significantly different at 5% of the fractions of dietary fiber (NDF and ADF). FL had the highest percentage of lignin. The percentage of hemicellulose was higher than that of cellulose and lignin in two types, with predominance of insoluble fiber. Microbiological analysis showed that (IF) the product is within the limits allowed by law. Cereal bars were produced adding 10, 20 and 30% of corn fiber (CF) with and without heating (W/ and W/O HE), and those submitted to physical-chemical, microbiological and sensory analyses. The bars with 20 and 30% CF and W/O HE, were the most dense (0.7 g/cm 3 ), that showed the highest specific volume was with 10% CF W/ HE, (1.7 cm 3 /g). With the increase in the percentage of fiber, the volume of the bars decreased. Water activity was in the range of 0.5, and pH ranged between 4.7 and 5.0, showing low acidity of the products. The lightness (L*) was between 42.8 and 51.0, increasing as the increase in the percentage of fiber. As for the chromaticity, the samples showed positive values of a* and b*. The hue (H*) varied from 68.1 to 71.5, noting the tendency toward yellow. In relation to the chroma (C*), in bars W/ HE, as you increase the percentage of fibers, the value of C* decreases in bars; in bars W/O HE, with... (Complete abstract click electronic access below) / Orientador: José Francisco Lopes Filho / Coorientador: Ana Carolina Conti-Silva / Banca: Vanessa Dias Capriles / Banca: Célia Maria Landi Franco / Mestre

Orientador: José Francisco Lopes Filho / Banca: Javier Telis Romero / Banca: Eduardo Micotti da Gloria / Resumo: Foi monitorada a hidratação dos germes dos grãos de milho macerados a 52ºC e 180 rpm, em 9 soluções formadas pelas combinações de três níveis de SO2 (0,0 ; 0,1 e 0,2%) e três níveis de ácido lático (0,0 ; 0,55 e 1,0%) em intervalos de tempos de 10 minutos até 36 horas. Para determinar os coeficientes efetivos de difusão da água no germe foi utilizada a solução proposta por Crank (1975) para a Segunda Lei de Fick. Os coeficientes de difusão foram da ordem de 10-6 cm2/s, valores até 10 vezes maiores que os reportados na literatura para o grão inteiro. Verificou-se que o ácido lático dificultou a hidratação nas primeiras 2 horas e facilitou em 24 horas de maceração, ao passo que o SO2 dificultou a hidratação em 24 horas de maceração. Numa segunda etapa, macerou-se 1kg de grãos de milho em 4 tratamentos que apresentaram maior hidratação e no tratamento convencional (36 horas, 0,2% SO2 e 0,55% ácido lático), determinando-se o rendimento, a porcentagem de danificação e o teor de óleo nos germes. Foi verificado que a primeira moagem do processo úmido deve ocorrer somente após o germe atingir umidade próxima de 50% b.u. e que o SO2 e o ácido lático são imprescindíveis para se obter germe de boa qualidade. / Abstract: Moisture content was measured at 15 steep times, from 10 minutes to 36 hours at 9 steep solutions made by combination between three levels of SO2 (0,0; 0,1; 0,2%) and three levels of lactic acid (0,0; 0,55; 1,0%). The solution of Fick's Second Law proposed by Crank (1975) was used to find the water effective diffusivity coefficients. The coefficients were in the order of 10-6cm2/s, and were up to 10 times faster them the values reported on the literature for diffusivity in the whole grain. Lactic acid decreased germ hydration during the first two hours of steeping and increased hydration at steeping time of 24 hours. SO2 decreased hydration for steeping time of 24 hours. On the second part of this work, 1kg of corn grains on the four treatments that showed to be of highest hydration and the conventional steeping treatment (36 hours, 0,2% SO2 and 1,0% lactic acid) were wet milled to recovery germ fraction. Percentage of germ yields, damages and oil content were determined and compared. Results showed that the first milling of the corn wet milling processes must occur only after the germ moisture content achieves approximately 50% w. b., and that SO2 and lactic acid are indispensable to obtain a high quality germ. / Mestre

De acordo com a Organização Mundial de Saúde, existem atualmente 17 doenças tropicais negligenciadas prevalentes em 149 países, afetando aproximadamente um bilhão de pessoas, a nível global. A leishmaniose, problema de saúde prevalente nos países em desenvolvimento, é endêmica em aproximadamente 98 países e territórios, com 350 milhões de pessoas em risco e 12 milhões de casos de infecção no mundo. A transmissão da doença ocorre pela picada de flebotomíneos fêmeas infectadas. Essa doença apresenta três formas principais: leishmaniose cutânea (LC), leishmaniose mucocutânea (LMC) e leishmaniose visceral (LV). Enquanto a leishmaniose cutânea é a forma mais comum da doença, a leishmaniose visceral é a mais grave e pode ser fatal se não for tratada. Em 2016, o Brasil reportou 3.626 e 12.690 casos de LC e LV, respectivamente. O candidato a fármaco hidroximetilnitrofural (NFOH) mostrou atividade contra o parasita da doença de chagas e da leishmaniose. Embora o NFOH seja promissor para o tratamento da leishmaniose, esse possui baixa solubilidade em água. A nanotecnologia tem sido empregada como plataforma para o desenvolvimento de formas farmacêuticas inovadoras com maior eficácia e segurança. A redução do tamanho de partículas em escala nanométrica permite aumentar a biodisponibilidade oral de fármacos pouco solúveis em água. Os nanocristais apresentam vantagens, tais como, o aumento da solubilidade de saturação e da velocidade de dissolução, decorrentes do aumento da área superficial da partícula. Além disso, esses apresentam maior adesividade às membranas biológicas, membrana celular e superfície do trato gastrointestinal. No presente trabalho utilizou-se a moagem por via úmida em escala reduzida para a obtenção dos nanocristais de NFOH. Diferentes tensoativos foram avaliados empregando o método selecionado, os tensoativos poloxamer 188 e poloxamer 407 foram os que favoreceram a redução do tamanho das partículas. Tal característica foi observada na caracterização físico-química das nanosuspensões de NFOH. A utilização desse método permitiu a obtenção de nanocristais de NFOH, com diâmetro hidrodinâmico médio (DHM) de 184,8 ± 0,5 a 325,9 ± 2,2 nm, índice de polidispersão (IP) de 0,21 ± 0,01 a 0,57 ± 0,01 e DHM de 191,3 ± 2,1 a 326,8 ± 4,6 nm e IP de 0,21 ± 0,01 a 0,50 ± 0,01, respectivamente para o poloxamer 188 e 407. O uso de ambos os tensoativos resultaram em distribuição monomodal de tamanho das partículas. As formulações foram obtidas por meio de planejamento fatorial completo e experimentos por superfície de resposta tendo como variáreis independentes as concentrações de NFOH, dos tensoativos e o tempo de moagem. A resposta, DHM, foi determinada utilizando espalhamento de luz dinâmica (DLS). Adicionalmente, as avaliações empregando calorimetria exploratória diferencial (DSC) e difração de raio X (DRX) revelaram que não houve interação entre o fármaco e os excipientes, assim como, não foi observada alteração na estrutura cristalina do NFOH. A microscopia eletrônica de varredura demonstrou a morfologia característica do estado cristalino. Além disso, a preparação liofilizada apresentou instabilidade após armazenamento por três meses a temperatura de 25 e 4 °C. / According to the World Health Organization, there are currently 17 neglected tropical diseases prevalent in 149 countries, affecting approximately one billion people globally. Leishmaniasis, a health problem prevalent in developing countries, is endemic in approximately 98 countries and territories, with 350 million people at risk and 12 million cases of infection worldwide. The transmission of the disease occurs by the bite of infected female sandflies. This disease has three main forms: cutaneous leishmaniasis (CL), mucocutaneous leishmaniasis (MCL) and visceral leishmaniasis (VL). While cutaneous leishmaniasis is the most usual form of the disease, visceral leishmaniasis is the most serious and can be fatal if left untreated. In 2016, Brazil reported 3.626 and 12.690 cases of LC and LV, respectively. The drug candidate for hydroxymethylnitrofurazone (NFOH) showed activity against the parasite of chagas disease and leishmaniasis. Although NFOH is promising for the treatment of leishmaniasis, it has low solubility in water. Nanotechnology has been used as a platform for the development of innovative pharmaceutical forms with greater effectiveness and safety. Particle size reduction on the nanoscale enables the oral bioavailability of poorly water-soluble drugs to be increased. Nanotechnology has been used as a platform for the development of innovative pharmaceutical forms, improving effectiveness and safety. Particle size reduction on the nanoscale enables the oral bioavailability of poorly water-soluble drugs to be increased. Nanocrystals have advantages such as increased saturation solubility and dissolution rate due to the increase in the surface area of the particle. In addition, this present greater adhesiveness to the biological membranes, cell membrane and surface of the gastrointestinal tract. In the present work, wet scale milling was used to obtain NFOH nanocrystals. Different surfactants were evaluated using the selected method, poloxamer 188 and poloxamer 407 surfactants favored the reduction of particle size. This characteristic was observed in the physical-chemical characterization of NFOH nanosuspensions. The use of NFOH nanocrystals with a mean hydrodynamic diameter (DHM) of 184.8 ± 0.5 to 325.9 ± 2.2 nm, polydispersity index (IP) of 0.21 ± 0, 01 to 0.57 ± 0.01 for poloxamer 188 and DHM of 191.3 ± 2.1 at 326.8 ± 4.6 nm and IP of 0.21 ± 0.01 at 0.50 ± 0.01 for poloxamer 407, both with monomodal size distribution. The formulations were obtained by means of complete factorial planning and surface response experiments having as independent variables the concentrations of NFOH, surfactants and milling time. The response, DHM, was determined using dynamic light scattering (DLS). In addition, evaluations using differential scanning calorimetry (DSC) and X-ray diffraction (DRX) revealed that there was no change in the crystal structure of NFOH and interaction between the drug and the excipients. Scanning electron microscopy demonstrated the characteristic morphology of the crystalline state. In addition, the lyophilized preparation was instable after storage for three months at 25 and 4 ° C.

Le processus de séparation gluten-amidon est un des éléments clés du procédé de fractionnement de la farine de blé, pour la production d'amidon, de produits dérivés de l'amidon et de gluten de blé. Le procédé industriel comprend une étape de malaxage du mélange farine/eau, une étape de dilution de la pâte obtenue et enfin des opérations de séparation gluten-amidon par tamisage ou centrifugation. Le procédé industriel est très consommatoire en eau, et plusieurs flux d'eau sont recyclés des étapes situés en aval du procédé vers les étapes en amont comme la préparation et la dilution de la pâte. L'objective de cette étude était d'étudier l'impact de ces flux d'eau recyclés sur l'agglomération du gluten, et d'identifier les principaux paramètres du procédé qui influencent le rendement d'extraction du gluten. Basé sur l'échantillonnage de plusieurs flux d'eau de différentes usines, un composant clé de ces flux d'eau recyclée a été identifié. Les mécanismes de développement de la pâte ont été étudiés à l'échelle laboratoire en utilisant un mélangeur planétaire (P600). La présence du composant au niveau de l'étape de préparation de la pâte retarde sa cinétique de développement et augmente l'énergie mécanique à fournir pour le développement. A l'échelle moléculaire ce composant ralentit la dépolymérisation des polymères de gluténine insolubles dans le SDS (UPP) de la farine lors du malaxage de la pâte. L'agglomération du gluten est contrariée par la présence de ce composé que ce soit au moment de la préparation de la pâte ou de sa dilution. Au cours de l'étape de dilution ce composé modifie chimiquement les arabinoxylanes de la farine, ce qui a un effet négatif très direct sur la capacité d'agglomération des protéines du gluten. Un paramètre de conduite de l'opération de malaxage a été identifié qui rend compte de la capacité d'agglomération du gluten (rendement du procédé) et de la distribution en taille des macromolécules de gluténines présentent dans le gluten extrait. Ce dernier paramètre est également sous l'influence de la composition en gluténines, codées par le locus Glu-1D du génome du blé. / The gluten-starch separation process is a key part of an industrial wheat fractionation plant, producing starch, starch-derived products, and vital wheat gluten. The industrial process consists of an initial flour hydration and dough mixing phase, a dough dilution step, followed by a gluten-starch separation by sieving or centrifugation. As this process is highly water consuming, several water streams are recycled from downstream unit operation of the process back upstream, to stages such as dough preparation and dough dilution. The aim of the present study was to investigate the impact of these recycled water streams on gluten agglomeration, and provide a further insight on the main process parameters influencing the gluten extraction yield. Based on the sampling of several water streams of different industrial plants, a key compound of these recycled water streams was characterized. A lab scale planetary mixer was used to study the dough development mechanisms. The presence of this compound at the dough preparation stage delayed dough development, as it increased the energy demand of the dough. On a molecular scale this constituent induced a delay of the depolymerization of SDS-insoluble glutenin (UPP) during dough mixing. Gluten agglomeration is impeded by this compound, both when present at the stage of dough preparation and dough dilution. The presence of this compound at the dough dilution stage chemically modified the flour arabinoxylans, impairing gluten agglomeration. A mixing parameter directly influencing both the molecular distribution of extracted gluten, as well as their agglomerating capacity, was proposed. The evolution of the molecular distribution of the extracted gluten with this mixing parameter was shown to be influenced by the wheat its glutenin composition, coded by the Glu-1D locus of the wheat genome.

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.

Made available in DSpace on 2014-06-11T19:23:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-30Bitstream added on 2014-06-13T19:50:11Z : No. of bitstreams: 1 rocha_cm_me_sjrp.pdf: 573913 bytes, checksum: 0c8f3d1213813d8ef7731ed231631de8 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente estudo objetivou determinar as características químicas e as frações componentes de fibras de milho, extraídas em laboratório (FL) e em processo industrial (FI) e elaborar barras de cereais adicionadas desta fibra com o propósito de agregar valor ao co-produto. A caracterização química foi realizada através de análises de umidade, cinzas, proteína, lipídeos, carboidratos disponíveis, Fibra em Detergente Neutro (FDN), Fibra em Detergente Ácido (FDA), hemicelulose, celulose, lignina, fibra alimentar total, insolúvel e solúvel. Os produtos analisados diferiram significativamente ao nível de 5% quanto às frações de fibra alimentar (FDN e FDA). FL deteve o maior percentual de lignina. O percentual de hemicelulose foi maior que o de celulose e lignina nos dois tipos, havendo predomínio da fração insolúvel da fibra. Análises microbiológicas da FI mostraram que o produto encontra-se dentro dos limites permitidos pela legislação. Foram produzidas barras de cereais adicionadas de 10, 20 e 30% de fibra de milho industrial (FM) com e sem forneamento (C/ e S/FN), e estas submetidas à analises físico-químicas, microbiológicas e sensorial. As barras com 20 e 30% FM S/FN foram as mais densas (0,7 g/cm3) e a que apresentou maior volume específico foi com 10% FM C/FN (1,7 cm3/g). Com o aumento dos percentuais de fibra observou-se a diminuição do volume das barras. A atividade de água ficou na faixa de 0,5 e o pH, variou entre 4,7 e 5,0, mostrando baixa acidez dos produtos. A luminosidade (L*) ficou entre 42,8 e 51,0, aumentando conforme o aumento do percentual de fibra. Quanto às cromaticidades, as amostras apresentaram valores positivos de a* e b*. A tonalidade cromática (H*) variou de... / The current study focused on determining the chemical characteristics and the fractional components of corn fibers, extracted in laboratory (FL) and industrial processing (FI) and producing cereal bars made from corn fiber intended to add value to the co-product. Chemical characterization was performed through the analyses of humidity, ashes, protein, lipids, available carbohydrates, neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, cellulose, lignin, total dietary fiber, insoluble and soluble. The products analyzed were significantly different at 5% of the fractions of dietary fiber (NDF and ADF). FL had the highest percentage of lignin. The percentage of hemicellulose was higher than that of cellulose and lignin in two types, with predominance of insoluble fiber. Microbiological analysis showed that (IF) the product is within the limits allowed by law. Cereal bars were produced adding 10, 20 and 30% of corn fiber (CF) with and without heating (W/ and W/O HE), and those submitted to physical-chemical, microbiological and sensory analyses. The bars with 20 and 30% CF and W/O HE, were the most dense (0.7 g/cm 3 ), that showed the highest specific volume was with 10% CF W/ HE, (1.7 cm 3 /g). With the increase in the percentage of fiber, the volume of the bars decreased. Water activity was in the range of 0.5, and pH ranged between 4.7 and 5.0, showing low acidity of the products. The lightness (L*) was between 42.8 and 51.0, increasing as the increase in the percentage of fiber. As for the chromaticity, the samples showed positive values of a* and b*. The hue (H*) varied from 68.1 to 71.5, noting the tendency toward yellow. In relation to the chroma (C*), in bars W/ HE, as you increase the percentage of fibers, the value of C* decreases in bars; in bars W/O HE, with... (Complete abstract click electronic access below)