This diploma thesis deals with the study of non-energy use of lignite. The main objective was to find an optimal recipe for the preparation of liquid and semi-solid (paste) hydrocolloids from the South Moravian lignite using the planetary mill and select the suitable dispersion medium with emphasis on possible use in agriculture. The used solutions were 10, 20 a 40 % w/w solutions of urea; 5, 10 a 15 % w/w solutions of citric acid; 1, 5 a 10 % w/w solutions of potassium chloride and deionized water. The best weight ratio for the preparation of lignite hydrocolloids is 1 part of lignite and 2 parts of the solution. The next part of this work is the isolation of humic acid from lignite hydrocolloids. The weight of isolated humic acids and amount of ash were compared to the used lignite hydrocolloids. Rheological behavior, particle size distribution, stability and thermal stablity of prepared lignite hydrocolloids were investigated. Correlation microscopy was used for determining elemental composition of selected location in the sample of lignite hydrocolloid.

<p dir="ltr">Macambo (<i>Theobroma bicolor</i>) is a relative of cacao that was identified as an underutilized crop in San Martín, Peru with potential for valorization. Current processing for macambo seeds results in waste of two-thirds of the fruit, so the two waste streams (husk and pulp-shell) were characterized by proximal analysis to identify useable components. From the pulp-shell waste, soluble polysaccharides and proteins were extracted. The resulting hydrocolloid formed physical gels that had predominantly solid-like elastic behavior and can partially recover after being deformed by a constant stress. Macambo pulp-shell waste has potential for extracting functional ingredients for thickening, forming gels, retaining water, and stabilizing emulsions.</p><p dir="ltr">One third of food in the United States is never eaten, and waste occurs throughout the food system. Produce is a significant portion of food waste, but shelf life can be extended by optimizing postharvest practices. Conducting precooling in-field at point of harvest with mobile units was proposed by researchers in the field of food waste reduction as an adaptable method to reduce food waste and was evaluated in this study for innovation and barriers to use. Based on expert interviews and a literature review, it was concluded that in-field precooling units are hindered by infrastructure requirements and effective precooling is already optimized at large scale with centralized cooling activities. Flexible cooling technology could be part of a solution for very small growers in the United States and internationally in developing economies, where access to precooling and full cold chain is still lacking.</p>

Emulsioner bildas då två vätskor som normalt sätt inte blandas med kraft vispas samman för att distribuera den ena vätskan i den andra. För att dessa vätskor inte efter avslutad vispning ska gå isär kan emulgeringsmedel tillsättas, till exempel polysackarider som hör till hydrokolloiderna. Hydrokolloider används inom livsmedelsindustrin för sin förmåga att påverka ett livsmedels reologiska egenskaper, så som viskositet och textur. Exempel på hydrokolloider som används inom den växtbaserade livsmedelsbranschen är derivat av cellulosa så som metylcellulosa. Metylcellulosan har egenskaper som löslighet i vatten samt termoreversibel gelatinering. Med detta menas att en lösning med metylcellulosa efter uppvärmning kommer att bilda en gel, men så fort temperaturen sjunker kommer viskositeten minska, och försvinna helt. Den huvudsakliga anledningen som ligger bakom intresset att utvärdera stabiliteten hos hydrokolloider är dagens allt större efterfrågan på växtbaserade proteinalternativ som efterliknar egenskaper hos de animaliska alternativen. Just stabiliteten av hydrokolloiderna är något som är svårt att utvärdera, men då kunskapen om konsistensgivare så som hydrokolloider blir allt större, ökar även möjligheten till bättre och fler modifierade proteinalternativ. Något som kan locka en större grupp konsumenter. Försöken som genomfördes gjordes med syftet att utvärdera egenskaperna hos metylcellulosa som konsistensgivare i en köttersättningsmix. En avgörande faktor vid beredningen är att kontrollera temperaturen. I försöken var den initiala temperaturer vid beredningen av emulsionerna innehållandes vatten, olja samt metylcellulosa antingen under 4°C eller över 4°C (10-15°C). Utöver detta  genomfördes även försök vid pH 5 samt pH 5,5. Metoder för att utvärdera stabiliteten hos emulsionerna utvecklades också. Data som erhölls bearbetades statistiskt och det visade sig att emulsioner tillverkade under 4°C hade en högre stabilitet än de som tillverkats vid temperaturer över 4°C. Skillnaden i stabilitet vid olika pH (pH 5,0 och pH 5,5) var däremot inte signifikant, men då försöken endast genomfördes med emulsioner med olja, vatten och metylcellulosa går det inte att med säkerhet säga att pH inte har någon signifikant effekt i en slutprodukt som även innehåller proteiner, stärkelse och kryddor. / Emulsions are formed when two liquids that does not combine naturally are mixed with force to distribute one liquid in the other. To prevent these liquids from separating when the mixing ends emulsifiers can be added, for example polysaccharides such as hydrocolloids. Hydrocolloids are used in the food industry for their ability to influence the rheological properties of a food, such as viscosity and texture. Examples of hydrocolloids used in the plant based food industry are cellulose derivates, such as methylcellulose. Methylcellulose has properties such as solubility in water and thermoreversible gelatinization. This means that the solution containing methylcellulose after heating will form a gel, but as soon as the temperature drops, the viscosity will decrease and vanish completely. The main reason to why a study of the stability in hydrocolloids is of interest is today's increasing demand for plant-based protein alternatives that largely have similar properties to the animal alternatives. The stability of hydrocolloids has previously been difficult to evaluate, but as knowledge about sensory enhancers such as hydrocolloids grows, so does the possibility of producing better and more reconstructed protein alternatives. Thus attracting a larger consumer group. The experiments that was carried out aimed at the evaluation of properties of methylcellulose as a sensory enhancer in a meat substitute mix. A critical point in the preparation is to control the temperature. The initial temperature during preparation of the emulsions containing water, oil and methylcellulose was either below 4°C or above 4°C (10-15°C). In addition, experiments were also performed at pH 5 and pH 5.5. Methods to measure the stability of the emulsions were also developed. The data obtained were processed statistically and the results indicated that emulsions prepared below 4°C had a higher stability than those prepared at temperatures above 4°C. Difference in stability due to pH, on the other hand, was not significant, but since the experiments were carried out with emulsions only containing oil, water and methylcellulose it is not possible to say with certainty that pH has no significant effect in a product containing more components such as protein, starch and spices.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-28T10:26:08Z No. of bitstreams: 2 Dissertação - Vilmara Araújo Franco- 2015.pdf: 917150 bytes, checksum: 8460671218b6552da3d9c0b792e9b8fe (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-28T10:27:53Z (GMT) No. of bitstreams: 2 Dissertação - Vilmara Araújo Franco- 2015.pdf: 917150 bytes, checksum: 8460671218b6552da3d9c0b792e9b8fe (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-01-28T10:27:53Z (GMT). No. of bitstreams: 2 Dissertação - Vilmara Araújo Franco- 2015.pdf: 917150 bytes, checksum: 8460671218b6552da3d9c0b792e9b8fe (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-09-30 / Celiac disease (CD) is a permanent intolerance to gluten, characterized by atrophy of the small intestine and consequent malabsorption of nutrients. Treatment of DC consists in the introduction gluten free diet permanently. The gluten-free bread is the product that celiac would like to find more easily in the market, allowing wider distribution of products with low cost, and convenience. This research aimed to characterize the flours of rice and sweet potatoes flour, formulate gluten-free bread for celiacs, applying different hydrocolloids (carboxymethyl cellulose and xanthan gum) and verify the effect of substitution of rice flour (RF) for sweet potatoes flour (SPF) on technological and sensory quality of bread. First, it determined the chemical composition of flour performing moisture analysis, water activity, acidity, pH, lipids, protein, ash, dietary fiber, carbohydrates, amylose content, grain size and color. Were also made microbiological analysis (Salmonella sp., Bacillus cereus, coliforms, molds and yeasts). Starch paste property was determined for RF, and their mixtures (25% and 75% RF, 50% and 50% RF, 75% SPF and 25% RF). At the second stage, the processing of breads occurred using the hydrocolloids carboxymethylcellulose (CMC) and xanthan gum (XG) in a farinaceous-based rice flour to develop gluten-free bread. Then, it was found the best results in respect to texture (hardness, elasticity, cohesiveness and chewiness), color (of the crust and crumb) and specific volume. Thus, it was held the replacement of rice flour by sweet potato flour and assessed their effects on textural parameters, color and specific volume, such as the acceptability of using sweet potatoes flour in bread formulation without gluten. For the production of bread were used rice flour (100%), granulated sugar (12%), water (150%), albumin (10%), margarine (10%), dried yeast (6%), salt (2%) and different concentrations of CMC and XG (in the values of 0%, 0,5%, 1,0%, 1,5% and 2%). The data were submitted to analysis of variance (ANOVA) and the averages compared by Tukey test (p ˂ 0,05). Yet, it was held microbiological analysis of the loaves and ordering preference test with consumers of bread. Flours differed significantly (p <0,05) according to L*, a* and b* color coordinates. The sweet potato flour presented itself darker than the rice one. In the characterization were obtained the following standards: sweet potatoes flour (moisture 9,18%, 9,92% protein, lipid 1,72%, 1,51% ash, 3,77% fiber and carbohydrates 77,81 %) and rice flour (13,31% moisture, 10,34% protein, 1,41% lipid, ash 0,31%, fiber 0,76%, carbohydrates 75,03%). In the assessment of paste properties of the flours and their mixtures, it was observed that RF paste temperature (88,65°C) was superior compared to the other samples. The maximum viscosity decreased with the increase of SPF in the blend. The values of final viscosity and retrogradation tendency decreased as increased SPF content in the mix. The paste properties of the mixtures of RF and SPF should be seen in a joint manner because they affect the texture in gluten-free breads. In gluten-free bread with rice flour processing it was discovered that for all the analyzes the control sample (without hydrocolloid) differed significantly (p <0,05) of others. It was found that with the use of 2% of CMC, there was obtained best results in relation to the set of analyzes, and sensorially there was no significant difference (p <0,05) between samples containing hydrocolloids. With the use of hydrocolloid CMC and replacement of RF for SPF, it was found that the higher the ratio of SPF, the lower the specific volume and the higher the hardness of the samples. However, the sample with 25% SPF was not significantly different compared to control hardness, chewiness, 10 cohesiveness and elasticity sample. The addition of SPF in the breads gave a darker color to the samples. The microbiological evaluation of the sample with 25% SPF resulted in a bread with a shelf life of 07 days. This same sample achieved a 80,3% acceptance rate, considered high for being a new product developed,. The analysis of only 2% purchase intent of tasters certainly would not buy the product, showing that the use of hydrocolloids combined with the use of sweet potato flour in gluten-free bread formulations, is an option for celiac public to obtain Products with sensorial quality. / A doença celíaca (DC) é uma intolerância permanente ao glúten, caracterizada por atrofia da mucosa do intestino delgado e consequente má absorção de nutrientes. O tratamento da DC consiste na introdução de dieta sem glúten de forma permanente. O pão sem glúten é o produto que os celíacos gostariam de encontrar com maior facilidade no mercado permitindo ampla distribuição dos produtos com baixo custo, além da praticidade. Esta pesquisa teve como objetivo caracterizar as farinhas de arroz e de batata-doce, elaborar pão isento de glúten para doentes celíacos, aplicando diferentes hidrocolóides (carboximetilcelulose e goma xantana) e verificar o efeito da substituição da farinha de arroz (FA) por farinha de batatadoce (FBD) na qualidade tecnológica e sensorial dos pães. Primeiramente, determinou-se a composição centesimal das farinhas realizando análises de umidade, atividade de água, acidez, pH, proteínas, lipídios, cinzas, fibra alimentar, carboidratos, teor de amilose, granulometria e cor; além das análises microbiológicas (Salmonela sp., Bacillus cereus, coliformes, bolores e leveduras). A propriedade de pasta do amido foi determinada para FA, FBD e suas mesclas (25% FBD e 75% FA; 50% FBD e 50% FA; 75% FBD e 25% FA). Na segunda etapa, ocorreu o processamento dos pães utilizando os hidrocolóides carboximetilcelulose (CMC) e goma xantana (GX) em base farinácea de farinha de arroz para desenvolvimento de pão sem glúten, em seguida, verificou-se o melhor resultado em relação à textura (dureza, elasticidade, coesividade e mastigabilidade), cor (da crosta e do miolo) e volume específico, com isso, realizou-se a substituição da farinha de arroz pela farinha de batata-doce e analisou os seus efeitos sobre os parâmetros texturais, cor e volume específico, tal como, a aceitabilidade do uso da farinha de batata-doce em formulação de pão sem glúten. Para a fabricação dos pães foram usados farinha de arroz (100%), açúcar cristal (12%), água (150%), albumina (10%), margarina (10%), fermento biológico seco (6%), sal (2%) e diferentes concentrações de CMC e GX (nos valores de 0%, 0,5%, 1,0%, 1,5% e 2%). Os dados foram submetidos a análise de variância (ANOVA) e as médias comparadas pelo teste de Tukey (p ˂ 0,05). Ainda, realizou-se análise microbiológica dos pães e teste de preferência por ordenação com consumidores de pães. As farinhas diferiram significativamente (p<0,05) em relação às coordenadas L*, a* e b* de cor, onde a farinha de batata-doce apresentou-se mais escura que a de arroz. Na caracterização obtiveram-se os seguintes padrões: farinha de batata-doce (umidade 9,18%, proteína 9,92%, lipídio 1,72%, cinzas 1,51%, fibras alimentares 3,77% e carboidratos 77,81%) e farinha de arroz (umidade 13,31%, proteína 10,34%, lipídio 1,41%, cinzas 0,31%, fibras alimentares 0,76%, carboidratos 75,03%). Na avaliação das propriedades de pasta das farinhas e de suas mesclas, observou-se que a temperatura de pasta de FA (88,65°C) foi superior em relação às demais amostras. A viscosidade máxima diminuiu com o aumento de FBD na mescla. Os valores de viscosidade final e de tendência à retrogradação diminuíram à medida que aumentou o teor de FBD na mescla. As propriedades de pasta das mesclas de FA com FBD devem ser vistas de forma conjunta, pois afetam a textura em pães sem glúten. No processamento de pão sem glúten com farinha de arroz detectou-se que para todas as análises a amostra controle (sem hidrocolóide) diferiu significativamente (p<0,05) das demais. Observou-se que com o uso de 2% de CMC obtevese o melhor resultado em relação ao conjunto de análises, e sensorialmente não foi detectada diferença significativa (p<0,05) entre as amostras contendo hidrocolóides. Com o uso do hidrocolóide CMC e a substituição de FA por FBD, detectou-se que quanto maior a proporção de FBD, menor foi o volume específico e maior a dureza das amostras. No entanto, a amostra com 25% de FBD não diferiu significativamente em relação ao controle na dureza, mastigabilidade, coesividade e elasticidade da amostra. A incorporação de FBD nos pães 8 conferiu uma cor mais escura às amostras. A avaliação microbiológica da amostra com 25% de FBD resultou em um pão com vida útil de 07 dias. Esta mesma amostra obteve um índice de aceitabilidade de 80,3%, sendo considerado alto por ser um novo produto desenvolvido, onde na análise de intenção de compra apenas 2% dos provadores certamente não comprariam o produto. Mostrando que o uso de hidrocolóides e a adição de farinha de batata-doce a formulações de pão sem glúten, é uma opção para o público celíaco obter produtos com qualidade sensorial.

Made available in DSpace on 2014-08-20T14:30:13Z (GMT). No. of bitstreams: 1 Tese_Gloria_Beatriz_Azevedo_Cubas.pdf: 1660996 bytes, checksum: 8bb44113acc263526d63d6f5e7e47e2b (MD5) Previous issue date: 2012-12-07 / The aims of this randomised controlled trial were to evaluate the influence of a preprocedural 0.12% chlorhexidine mouthrinse on the microbial contamination of dental impressions, subsequently disinfected with sodium hypoclorite or water (control). The second objective was to evaluate if aqueous solution of 0.12% chlorhexidine mixed with irreversible hydrocolloid powder would decrease microbial contamination of dental impressions. Forty subjects underwent maxillary dental impressions with irreversible hydrocolloid and were randomly divided into two groups (n=20) according to the preprocedural mouthrinse (0.12% chlorhexidine or placebo).The dental impressions were then divided into two subgroups and disinfected with sodium hypochlorite or water (control). In the second part, 20 subjects underwent maxillary dental impressions with irreversible hydrocolloid and randomly assigned into two groups according to the mixed agent used (0.12% chlorhexidine or water). Saliva and alginate samples were assessed for microbiological counts of total micro-organisms, total streptococci and Candida species. Surface roughness of the impressions and dimensional stability of the casts were also evaluated. Chlorhexidine preprocedural mouthrinse significantly reduced (p<0.05) microbial contamination. Small but significant alterations were produced on dimensional stability and surface quality when sodium hypochlorite was used as disinfectant after the impression (p=0.005). The results also showed that the use of aqueous 0.12% chlorhexidine mixed with the powder of irreversible hydrocolloid decreased the percentage of total micro-organisms and total Streptococci counts (p<0.001), without producing alterations in surface quality and dimensional stability. It can be concluded that 0.12% chlorhexidine used as preprocedural mouthrinse, or mixed with irreversible hydrocolloid powder, are effective methods in reducing microbial contamination of alginate impressions, without causing damage to the physical and mechanical properties of the material / Os objetivos deste ensaio clínico randomizado foram (I) avaliar a influência de um bochecho, com solução de clorexidina 0,12% e placebo, previamente a realização de moldagens bucais, posteriormente desinfetadas com hipoclorito de sódio ou água (controle) na contaminação de moldagens de alginato; e (II) avaliar se solução aquosa de clorexidina 0,12% misturada com o pó de hidrocolóide irreversível reduziria a contaminação microbiana de moldagens bucais.Quarenta voluntários foram submetidos a moldagens bucais com hidrocolóide irreversível e foram divididos de forma randomizada em 2 grupos (n=20) de acordo com a solução bucal (0,12% clorexidina ou placebo). As moldagens bucais foram divididas em 2 grupos e desinfetadas com hipoclorito de sódio ou água (controle). Na segunda parte do ensaio clinico, 20 voluntários foram submetidos a moldagens bucais com hidrocolóide irreversível e foram divididos em 2 grupos de acordo com a solução usada no preparo do alginato (0,12% clorexidina ou água).Amostras de saliva e alginato foram avaliados quanto a contagem microbiana de microrganismos totais, estreptococos totais e espécies de Candida. Rugosidade de superfície e estabilidade dimensional de modelos de gesso também foram avaliados. Bochecho com solução bucal de clorexidina reduziu de forma significativamente (p<0,005) a contaminação microbiana. Pequenas mais significativas alterações dimensionais e de rugosidade de superfície foram produzidas quando hipoclorito de sódio foi utilizado como agente desinfetante pós-moldagem (p=0,005). Os resultados também demonstraram que o uso de solução de clorexidina 0,12% misturada ao pó de hidrocolóide irreversível reduziu a percentagem de microrganismos totais e estreptococos (p<0.001), sem causar alterações de rugosidade de superfície e estabilidade dimensional. Pode ser concluído que o uso de solução de clorexidina 0,12% usada como bochecho bucal ou misturada ao pó de hidrocolóide irreversível são métodos eficientes na redução microbiana de moldagens de alginato, sem causarem danos as propriedades físicas e mecânicas do material