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Physicochemical properties and microencapsulation process development for fish oil using supercritical carbon dioxideSeifried, Bernhard Unknown Date
No description available.
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Influence of stockplant management on yield and subsequent rooting of cuttings of cold-tolerant Eucalyptus grandis x E. nitens clones.Ziganira, Matabaro. January 2012 (has links)
Clones of the Eucalyptus grandis x Eucayptus nitens (GN) hybrids were produced and selected through the CSIR‟s breeding programmes for colder plantation sites in South Africa. Some GN clones consistently exhibit high and superior pulp properties, which makes them valuable for commercial plantations in South Africa. In nurseries, stockplants are usually seven cm in length and maintained at high (100 x1.5 m-2) planting density. However, rooting frequency varies with season and little is known about the impact of position of cuttings on overall rooting frequency of a clone. The aim of this study was to investigate the effect of size and planting density of stockplants in mini-hedges, on the yield and subsequent rooting of cuttings from various positions of GN clones of known rooting potential (i.e. GN 018B: difficult-to-root and PP 2107: easy-to-root clones).
Stockplants (10 cm vs. 20 cm) were established at high (100 x 1.5 m-2) and at low (25 x 1.5 m-2) densities for GN 018B and PP 2107 under commercial nursery conditions in a polyethylene tunnel. Cuttings were harvested every two to three weeks in September-October 2010 (spring), December 2010-January 2011 (summer), April-May 2011 (autumn) and June-July 2011 (winter). The harvested material was 5 – 7 cm in length and the light intensity received by individual stockplants at the two planting density levels was recorded. Harvested cuttings from the three positions (apical, middle and basal shoots) were used for: (i) rooting experiments under nursery conditions, (ii) bio-stimulant analysis using the mung bean bioassay, and (iii) analysis of soluble sugars.
Between spring and summer 2010, the two GN clones established at low density yielded a similar number of cuttings, but differences in the rooting frequencies were significant in favour of PP 2107 clone. Similar observations were made at high density in terms of production of cuttings, but the significant differences in the rooting observations were reversed between the clones. The GN 018B clone had low rooting rates in summer under nursery conditions but its tissue extracts promoted higher rooting in the bioassay during that time, when compared to spring. Spring and summer had similar effects on rooting responses of PP 2107 cuttings in nursery and bioassay experiments. For both clones, short stockplants produced fewer cuttings but had a higher rooting frequency than cuttings from tall stockplants, with a high rooting frequency recorded from basal cuttings. Similar results
were observed in the bioassay experiments which showed high rooting potential of mung bean hypocotyls cuttings using tissue extracts of PP 2107 cuttings maintained at high planting density. Although apical cutting tissues had high concentration of sugars (i.e. sucrose, glucose and fructose), their rooting rates were usually lower at high and low planting density compared to middle and basal cuttings. Sucrose concentration was the highest sugar present in stockplants grown under low planting density. A higher and lower rooting frequency was also observed in autumn although the two clones responded differently to Quambalaria eucalypti (Sporothrix eucalypti) disease infestations. Position, size and genotype had a significant impact on type and concentration of sugar (i.e. sucrose, glucose and fructose), particularly in PP 2107 clone, although rooting rates in the bioassay did not correlate with sugar contents of Eucalyptus cuttings.
High carbohydrate (i.e. soluble sugar) content and auxin concentration increased production and subsequent rooting of cuttings across both clones, particularly in spring. Furthermore, rooting was enhanced by relatively higher light intensity intercepted by individual stockplants and in particular the GN 018B clone. Light intensity in the high and low planting densities caused variation in the rooting frequencies thereby increasing or decreasing soluble sugar and auxin concentrations of the two clones. Light intensity and fertiliser concentration received by tall and short stockplants impacted on endogenous hormone levels thereby increasing or decreasing rooting. High sugar concentration levels of PP 2107 clone increased its susceptibility to fungal infection thereby decreasing its rooting frequency in autumn, as its rooting rates increased in winter.
Overall results of the investigation revealed that PP 2107 clone has higher rooting potential than GN 018B clone, in particular at high planting density and if stockplants are not infected by fungal diseases. Higher sugar levels were recorded in spring for PP 2107, although rooting rates of mung bean hypocotyl cuttings were higher in summer for GN 018B, suggesting that sugars have nothing to do with rooting of GN cuttings. Season, planting density and size of stockplants affect the rooting frequency of GN clone. Thus, short stockplants maintained at low and high planting densities are recommended for GN 018B and PP 2107 respectively, although the impacts of fertilisers and pathogen resistance on rooting rates still need to be investigated under similar conditions. / Thesis (M.Sc.Agric.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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Management of Natural Stands of Acacia seyal Del. variety seyal (Brenan) for Production of Gum Talha, South Kordofan, SudanHamed Mohammed, Mohammed 29 June 2011 (has links) (PDF)
The present study was conducted in Umfakarin natural forest reserve, South Kordofan, Sudan. The main objective was to investigate the possibility of managing Acacia seyal Del. variety seyal for the production of gum talha. Three stand densities (strata), namely dense, medium, and slight, were distinguished based on the number of trees per hectare. During the sampling phase, the study adopted the method of identifying the competitors (neighboring trees) from the subject one (trees selected for gum production experiments). From the three stand densities, a total of 482 subject trees, covering variable diameter ranges (d= 9-11.5, 13.5-16, 18-20.5 and above 21 cm) were selected, based on the diameter at 0.25 m height (d0.25). In each stratum, competitor trees were identified within a radius equal to the height of subject tree multiplied by a factor (1.25). The diameter at breast height, height to crown base, height, crown radii, and tree coordinates were measured for each of the subject trees and its competitors. Subject trees were exposed to tapping on first of October, the fifteenth of October, and the first of November, using local tools (Sonki and Makmak). Additionally, untapped trees were used as controlling-variables. The initial gum collection was completed fifteen days after the tapping, while the subsequent (7-9 pickings) were done at an interval of fifteen days.
Six stand height functions were tested and the results illustrated that the Michailow stand height function was suitable for predicting the height of Acacia seyal in Umfakarin natural forest. The predictive ability of this height function ranged from 19.3% to 24%. The volume function used in this study was able to predict the volume of standing trees with more than 92 percent accuracy.
Competition among trees of Acacia seyal was assessed in terms of competition indices. Eight competition indices were quantified using the CroCom program. The relationship between these indices and tree dimensions (diameter at breast height, height and crown diameter) was tested using logarithmic models. Among these indices, the Hegyi_2 index is considered a suitable index to be applied for estimating the degree of competition in natural stands of A. seyal of dense stratum when using diameter at breast height as a predictor. About 70% of the total variability is explained by this logarithmic model.
Gum yielded by each subject tree per season was obtained by summing up the gum samples collected from all pickings. Gum production per unit area was also determined. Regression tree, general linear model (GLM) and logistic regression techniques were used for analyzing the obtained data. The results of the study indicated that the gum yield is independent of stand density. Tapping has influence on gum yield. Trees tapped by sonki on the first of October at medium stand density have the highest gum with an average value of about 56 g/tree/season. Significant difference (p = 0.021) was detected between two groups of dates; the first of October and first of November in medium stand density. The results also revealed that the most important variable influencing gum production was found to be diameter at breast height with 23.95 cm threshold. Between 41-53 percent of subject trees produce gum less than 50 g/season. The results indicated that A. seyal species produces a very low quantity of gum talha (3.6-4.8 kg/ha) and for economic reasons, its tapping is not recommended. The findings of the regression analysis revealed to a model which could be used to estimate the yield of gum talha from A. seyal natural stands in the Umfakarin forest, South Kordofan, Sudan. Conducting experiments on the production of gum talha in permanent plot trials in different climatic regions of the Sudan is highly recommended.
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Caractéristiques mécaniques et thermiques de l’argile stabilisée par la gomme arabique et renforcée par la paille de riz / Mechanical and thermal characteristics of stabilized clay by gum arabic and reinforced by rice strawAbakar, Ali 28 June 2018 (has links)
Le réchauffement climatique et le coût élevé des matériaux de construction conventionnels (ciment, chaux, acier) nous obligent à recourir aux matériaux locaux, disponibles et sans effet négatif sur l’atmosphère. Il s’agit de blocs de terre comprimée (BTC) stabilisés par de la gomme arabique et renforcés avec de la paille de riz. L’objectif principal de ce travail est la valorisation des matériaux locaux et écologiques pour la construction des habitations durables. L’étude concerne la caractérisation mécanique, thermique et la durabilité des éprouvettes fabriquées avec de l’argile, du sable, de la gomme arabique, de la paille de riz et de l’eau en des différentes proportions. A cet effet, les pourcentages massiques de gomme arabique sont de 5%, 10% et 15%. Ceux de la paille de riz sont de 0,5%, 1%, 1,5% et 30% de sable sont retenus pour ce travail de recherche. Des briques en BTC de 30 x 15 x 8 cm et des éprouvettes de dimension 4 x 4 x 16 cm sont fabriquées pour réaliser les essais mécaniques. Une méthode « fil chaud » adaptée sur les éprouvettes cylindriques de 16 cm de diamètre sur 32 cm de hauteur est utilisée pour la détermination des conductivités thermiques. L’utilisation de la gomme arabique comme liant dans la construction a donné des résultats satisfaisants. A un taux de 15% de gomme arabique associée à une contrainte de compactage beaucoup plus élevée, nous permettent d’obtenir des BTC ayant une résistance mécanique acceptable ainsi qu'une meilleure résistance à l’eau de pluie. Les résultats mécaniques montrent que la gomme arabique améliore la résistance mécanique de même que la contrainte de compactage. Par contre l’utilisation de paille de riz dans le mélange fait chuter sa résistance mécanique et allège le matériau. Les valeurs de conductivité thermique mesurées, montrent que les différents échantillons ne peuvent pas être considérées comme étant des matériaux isolants. Les éprouvettes exposées aux aléas climatiques (pluie et humidité) pendant un mois montrent que les blocs de terre non stabilisés se sont détériorés sous la pluie. Par contre les éprouvettes stabilisées par la gomme arabique ont conservé leurs bonnes tenues. De même, des éprouvettes stabilisées et non stabilisées sont immergées dans l’eau. A partir de 15 min, toutes les éprouvettes sont détériorées. Les matériaux argileux stabilisés par la gomme arabique ne pourront pas servir en fondation dans la construction. Ce travail de recherche sera complété par des essais de vieillissement du matériau sur des différents échantillons pour sa validation comme nouveau matériau de construction durable / Global warming and the high cost of conventional building materials (cement, lime, steel) force us to use local, available materials with no negative effect on the atmosphere. These are compressed earth blocks (BTC) stabilized with arabic gum and reinforced with rice straw. The main objective of this work is the valorization of local and ecological materials for the construction of sustainable homes. The study concerns the mechanical, thermal and durability characterization of specimens made of clay, sand, arabic gum, rice straw and water in different proportions. For this purpose, the percentages of gum Arabic are 5%, 10% and 15%. Those of rice straw are 0.5%, 1%, 1.5% and 30% of sand are retained for this research work. BTC bricks measuring 30 x 15 x 8 cm and specimens measuring 4 x 4 x 16 cm are manufactured to perform the mechanical tests. A "hot wire" method adapted to cylindrical specimens 16 cm in diameter and 32 cm in height is used for the determination of thermal conductivities. The use of arabic gum as a binder in the construction has given satisfactory results. At a rate of 15% gum Arabic associated with a much higher compressive stress, allow us to obtain BTCs having an acceptable mechanical strength as well as a better resistance to rainwater. Mechanical results show that gum Arabic improves mechanical strength. As is the compaction constraint. By cons the use of rice straw in the mixture reduces its mechanical strength and lightens the material. The measured thermal conductivity values show that the different formulations cannot be considered as insulating materials. The specimens exposed to the climatic hazards (rain and moisture) for a month show that the unstabilized earth blocks have deteriorated in the rain. On the other hand, samples stabilized by gum Arabic have retained their good habits. Similarly, stabilized and unstabilized specimens are immersed in water. From 15 min, all test pieces are deteriorated. The clay materials stabilized by gum Arabic can not be used as a foundation in construction. This research work will be completed by aging tests on the various formulations for validation as a new sustainable building material
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Obtenção, caracterização e avaliação da estabilidade de extrato do urucum nanoencapsulado em goma do cajueiro / Obtenção, caracterização e avaliação da estabilidade de extrato do urucum nanoencapsulado em goma do cajueiroAguiar, Nágela Martins Oliveira January 2013 (has links)
AGUIAR, Nágela Martins Oliveira Aguiar. Obtenção, caracterização e avaliação da estabilidade de extrato do urucum nanoencapsulado em goma do cajueiro. 2013. 78 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrária, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2013 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-22T12:53:13Z
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Previous issue date: 2013 / Consumers demands for healthier eating are increasing, which has led the industry to invest more persistent in the use of natural products. One of more relevant segment is natural substances acting as pigments, replacing the artificial coloring. Due his high instability, several researches have been directed to determine favorable conditions of use of these substances. Among the compounds studied we have bixin, a natural pigment, carotenoid, lipid-soluble annatto seed extract (Bixa orellana L.). Most carotenoids are sensitive to factors such as high temperature, light, oxygen and low pH, which restricts its use as a pigment in some food products. The use of nanoencapsulation has been an alternative for improving the stability of pigments such as bixin, making possible its incorporation into food systems without loss of its qualities. Considering that, the present study aimed to obtain, characterize and assess the stability of nanocapsules containing annatto extract, employing the cashew gum as wall material. To obtain these nanocapsules were performed steps of preparation of the emulsion and spray drying. The nanocapsules were characterized and showed a average size of 24.17nm + 3.71 with distribution by volume of 97.33% + 2.08, demonstrating high degree of homogeneity in size. The solubility of the nanocapsules was 74.13% + 3.68 and the efficiency achieved in the process of nanoencapsulation was 44.74% + 4.38. Stability tests were made with nanocapsules storing them in conditions of absence and presence of light. During ten days, for forty days, was made the determination of colorimetric coordinates a*, b*, L*, C*, Hue angle and the determinations of the levels of total bixin and superficial bixin. The total bixin had a reduction of 78,48% for the nanocapsules exposed to light, while in condition of absence of light the reduction was only 41.88%. The values of surperficial bixin or unencapsulated, ranged from 27.64 mg/100g to 8.65 mg/100g, for samples subjected to light, and from 27,64 mg/100g + 2,13 a 16,45 mg/100g + 0,80 for samples stored in absense of light. The nanocapsules showed greater stability when stored away from light, confirming the deleterious light effect in annatto extract and therefore not full protection of cashew gum as wall material. Were also found in this study the antioxidant activities (using the system β-caroteno/ acid linoleic) and antimicrobial (by disk diffusion) of nanocapsules containing annatto extract. In relation to the antioxidant activity (inhibition of the oxidation of β-carotene) was obtained average perceptual corresponding to 61.90%, 54.576%, and 51.73% for containing extracts of nanocapsule concentration of 40 mg/L, 30 mg/L and 20 mg/L. The results suggests antimicrobial activity of the nanocapsules, making an inhibition zone against Staphylococcus aureus using concentrations of 1 mg/L, 2 mg/L and 10 mg/L, however there was observed the formation of inhibition zones for Escherichia coli and Salmonella choleraesuis. In this study, nanocapsules containing annatto extract were applied to the model system (buffer) and food system (yogurt). The stability of these systems was measured using the colorimetric parameters, during five days, for 40 days. It was observed that the system model may have promoted the nanocapsule stability, retaining their nucleus. When applied in yoghurt gave the nanocapsules to this food yellow / orange coloration and during the storage period was reduced values of a* and increased b* and C* parameters. / As exigências dos consumidores por uma alimentação mais saudável são cada vez maiores, o que tem levado a indústria a investir de forma mais persistente no uso de produtos naturais. Um dos segmentos de investimento de destacada importância, é o de substâncias naturais que atuem como pigmentos, em substituição aos corantes artificiais. Devido à alta instabilidade destas substâncias, diversas pesquisas têm buscado determinar condições favoráveis para seu uso. Dentre as substâncias estudadas tem-se a bixina, um pigmento natural, carotenoide, lipossolúvel, extraído da semente do urucuzeiro (Bixa orellana L.). A maioria dos carotenóides é sensível a fatores como alta temperatura, luz, oxigênio e baixo pH, o que restringe o seu emprego como pigmento em alguns produtos alimentícios. O uso da nanoencapsulação tem sido uma alternativa para melhorar a estabilidade de pigmentos como a bixina, tornando possível sua incorporação em sistemas alimentícios sem a perda de suas propriedades. Considerando o exposto, o presente trabalho teve por objetivo obter, caracterizar e avaliar a estabilidade de nanocápsulas contendo extrato do urucum, empregando a goma do cajueiro como material de parede. Para a obtenção das nanocápsulas foram realizadas as etapas de preparo da emulsão e atomização. As nanocápsulas obtidas foram caracterizadas e apresentaram tamanho médio de 24,17 nm + 3,71, com distribuição por volume de 97,33% + 2,08, o que demonstrou considerado grau de homogeneidade de tamanho. A solubilidade das nanocápsulas foi de 74,13% + 3,68 e a eficiência alcançada no processo de nanoencapsulação foi de 44,74% + 4,38. Os testes de estabilidade das nanocápsulas foram feitos armazenando-as em condições de ausência e presença de luz. A cada dez dias, durante quarenta dias, fez-se a determinação das coordenadas colorimétricas a*, b*, L*, C* e ângulo Hue e as determinações dos teores de bixina total e bixina superficial. A bixina total teve uma redução de 78,48% para as nanocápsulas expostas à luz, enquanto que na condição de ausência de luz essa redução foi de apenas 41,88%. Os valores de bixina superficial, ou não encapsulada, oscilaram de 27,64 mg/100g a 8,65 mg/100g, para amostras submetidas à luz, e de 27,64 mg/100g + 2,13 a 16,45 mg/100g + 0,80 para amostras armazenadas na ausência de luz. As nanocápsulas mostraram maior estabilidade quando armazenadas ao abrigo da luz, comprovando o efeito deletério da luz ao extrato de urucum e, portanto, a não total proteção da goma de cajueiro como material de parede. Também foram verificadas nesta pesquisa as atividades antioxidante (utilizando-se o sistema β-caroteno/Ácido Linoléico) e antimicrobiana (pelo método de disco-difusão) das nanocápsulas contendo extrato do urucum. Em relação à atividade antioxidante, obteve-se percentual médio de inibição da oxidação do β-caroteno correspondente a 61,90%, 54,576% e 51,73%, para os extratos contendo concentrações de nanocápsulas de 40 mg/L, 30 mg/L e 20 mg/L. Os resultados obtidos sugerem atividade antimicrobiana das nanocápsulas, com formação de halo de inibição frente ao Staphylococcus aureus utilizando-se as concentrações de 1 mg/L, 2 mg/L e 10 mg/L, porém não foi observada a formação de halos de inibição para os microrganismos Escherichia coli e Salmonella choleraesuis. Neste estudo as nanocápsulas contendo o extrato do urucum foram aplicadas em sistema modelo (solução-tampão) e em um sistema alimentício (iogurte). A estabilidade desses sistemas foi medida através dos parâmetros colorimétricos, a cada cinco dias, durante 40 dias. Observou-se que o sistema modelo pode ter promovido estabilidade às nanocápsulas, conservando seus núcleos. Quando aplicadas em iogurte as nanocápsulas conferiram a este alimento uma coloração amarelo/alaranjado e durante o período de armazenamento houve redução dos valores de a* e aumento dos parâmetros b* e C*.
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Avaliação das características estruturais de bolos com redução calórica / Evaluation of structural characteristics of cakes with reduced caloricCavalcante, Rosane Souza January 2012 (has links)
CAVALCANTE, Rosane Souza. Avaliação das características estruturais de bolos com redução calórica. 2012. 50 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Departamento de Tecnologia de Alimentos, Programa de Pos-Graduação em Ciências e Tecnologia de Alimentos, Fortaleza-CE, 2012 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-23T13:35:25Z
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Previous issue date: 2012 / The consumption of cakes with calorie reduction is growing, but has presented challenges to be overcome in the formation of its structure when the sugar or fat are replaced by sweeteners, gums, thickeners or fat substitutes. The present study was to investigate the internal characteristics of cakes with calorie reduction and viability of producing the same pattern similar to conventional cake. Initially, we defined the mixing time and mass of fat source to be used in the formulation, using as parameter the specific volume. Next, we determined the pattern of the cake formulation from a factorial experimental design of the simple type, measuring the specific volume and cell count. From this formulation, sucrose and fat were partially substituted for the production of calorie reduced cake. Replacement of sugar was made in proportion of a mixture of xanthan gum (1.5%) and sucralose (1%), while the zein was used to replace fat. In cakes with sugar lowering evaluated the specific volume (VE), the cell count (CC) of the cakes, the apparent viscosity of the mass and its thermal properties by differential scanning calorimetry (DSC). In cakes with reduced fat content, the analyzes were VE, CC and apparent viscosity. It was found that the cake with increased VE was prepared with one hydrogenated vegetable fat and one (1) minute of mixing the dough. The standard formulation was defined as having 155.88 and 28.78 shares of sugar and fat, respectively. As the sugar content decreased (10.00 to 52.17%) were reduced specific volume (1.94 to 0.7 ml / g) and cell counts (from 36.2 to 4.0 cells / cm ²) the cake and the apparent viscosity of the mass (337.56 to 631.40 cP). By reducing the fat content, there were no significant differences between the samples for VE, CC and viscosity, and viable to produce cake with reduced calorie fat replacing up to 46.86%. For the results, it was observed that replacement of sugar contributed more sharply than the replacement of fat in the formation of defects in the structure of the cake. Thermograms of the mass of standard and cakes with reduced sucrose suggested that the presence of sucralose can reduce the starch gelatinization temperature, accelerating the process and causing a compression of the structure during baking, thereby facilitating the coalescing of bubbles dispersed in mass. / O consumo de bolos com redução calórica vem crescendo, mas tem apresentado desafios a serem superados na formação da sua estrutura quando o açúcar ou a gordura são substituídos por adoçantes, gomas, espessantes ou substitutos de gordura. O presente trabalho propôs avaliar as características internas de bolos com redução calórica e a viabilidade de produção do mesmo com características similares ao bolo convencional. Inicialmente, foram definidos o tempo de mistura da massa e a fonte de gordura a ser utilizada na formulação, utilizando-se o volume específico como parâmetro. Em seguida, determinou-se a formulação do bolo padrão a partir de um delineamento experimental do tipo fatorial simples, medindo-se volume específico e a contagem de células. A partir dessa formulação, a sacarose e a gordura foram parcialmente substituídos para a produção de bolos com valor calórico reduzido. A substituição do açúcar foi feita proporcionalmente por uma mistura de goma xantana (1,5%) e sucralose (1%), enquanto a zeína foi usada para substituir a gordura. Nos bolos com redução de açúcar avaliou-se o volume específico (VE), a contagem de células (CC) dos bolos, a viscosidade aparente da massa e as suas propriedades térmicas por meio de calorimetria diferencial de varredura (DSC). Nos bolos com redução do teor de gordura, as análises realizadas foram VE, CC e viscosidade aparente. Verificou-se que o bolo com maior VE foi aquele elaborado com gordura vegetal hidrogenada e 1 (um) minuto de mistura da massa. A formulação padrão foi definida como tendo 155,88 e 28,78 partes de açúcar e de gordura, respectivamente. À medida que o teor de açúcar decresceu (10,00-52,17%) foram reduzidos o volume específico (1,94-0,7 mL/g) e a contagem de células (36,2 – 4,0 cél/cm²) do bolo e a viscosidade aparente da massa (337,56-631,40 cP). Com a redução do teor de gordura, não foram observadas diferenças significativas entre as amostras para VE, CC e viscosidade aparente, sendo viável a produção do bolo com redução calórica substituindo-se a gordura em até 46,86%. Pelos resultados encontrados, foi observado que a substituição do açúcar contribuiu mais acentuadamente que a substituição da gordura na formação de defeitos na estrutura do bolo. Os termogramas das massas dos bolos padrão e com redução de sacarose sugeriram que a presença de sucralose pode reduzir a temperatura de gelatinização do amido, acelerando esse processo e causando uma compactação da estrutura durante o assamento, favorecendo assim a coalescência das bolhas dispersas na massa.
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UTILIZAÇÃO DE FARINHA DE CHIA (Salvia hispânica) NA ELABORAÇÃO DE PÃO SEM GLÚTEN SEM ADIÇÃO DE GOMA E GORDURA / THE USE OF CHIA (hispanic Salvia) FLOUR ON PREPARATION OF GLUTEN FREE BREAD WITHOUT GUM AND FATHuerta, Katira da Mota 12 March 2015 (has links)
Celiac disease is a permanent intolerance to gluten and its treatment is based in the total removal of these dietary proteins . The chia seed is highly nutritious because of the high content of protein, dietary fiber and essential fatty acids. In presence of water the seed exudes a transparent mucilaginous gel that has emulsifying properties, becoming it an excellent ingredient for use as a substitute for fats and starches in the baking industry. This work aimed to evaluate the effect chia flour (Salvia Hispanic L.) in the physical, microbiological, nutritional and sensory gluten-free breads prepared without addition of starch and fat. Chemical composition analysis were carried out at the flour and developed products. To determine the quality of the bread was developed analyzes of specific volume, mass rearing, cooking losses , water activity , texture, crust color and crumb . The count of yeasts and molds was held for five days of storage and the acceptability and purchase intent of the bread was evaluated by an affective test with 50 untrained volunteers. The chemical composition of the bread indicates that the presence of chia flour increases the nutritional value and provides the decrease in carbohydrate content . All the texture parameters were influenced by partial replacement of rice and soybean flour by chia flour. Also the color of the bread became darker and decreased the specific volume and the losses caused during cooking. Regarding sensory analysis, for bread prepared without gum , the formulation containing 2.5% of chia in replacement of rice and soy flour was the most accepted with values close to 5 score on the scale represented by " liked ". On the other hand, for bread prepared without fat all the treatments showed no significant difference for flavor and texture from the standard sample. Also, the treatment with 2.5% of chia flour showed purchase intention similar to the standard for both cases . The addition of chia flour on gluten-free breads without gum and fat resulted in a healthy food product alternative for celiac consumer. However we suggest more studies to improve the bread texture parameters. / A doença celíaca é uma intolerância permanente ao glúten e seu tratamento consiste basicamente na remoção total dessas proteínas da dieta. A chia é um grão altamente nutritivo devido ao seu elevado conteúdo de proteínas, fibra alimentar e ácidos graxos essenciais, em presença de água, ela exsuda um gel transparente mucilaginoso que possui propriedades emulsificantes, isso a torna um excelente ingrediente para ser utilizado como substituto de gorduras e gomas na indústria da panificação. Este trabalho teve como objetivo avaliar o efeito da farinha de chia (Salvia hispânica L.) na qualidade física, microbiológica, nutricional e sensorial de pães sem glúten elaborados sem adição de goma e gordura. Foram realizadas análises de composição química nas farinhas e nos produtos desenvolvidos. Para determinar a qualidade dos pães, foram desenvolvidas análises de volume específico, elevação da massa, perdas por cocção, atividade de água, textura, cor da crosta e miolo. A contagem de bolores e leveduras foi realizada durante cinco dias de estocagem e a aceitabilidade e intenção de compra dos pães foi avaliada através de um teste afetivo com 50 provadores não treinados. A composição centesimal dos pães indica que a farinha de chia quando adicionada a formulação aumenta o valor nutricional e diminui o teor de carboidratos. Todos os parâmetros de textura foram influenciados com a substituição parcial das farinhas de arroz e soja por farinha de chia, a cor dos pães tornou-se mais escura e houve diminuição do volume específico e das perdas ocasionadas durante a cocção. Com relação a análise sensorial, para os pães elaborados sem goma, a formulação que continha 2,5% de farinha de chia em substituição as farinhas de arroz e soja foi a mais aceita com valores próximos a 5, escore representado na escala por gostei , já para os pães elaborados sem gordura todos os tratamentos não apresentaram diferença significativa para sabor e textura com relação ao padrão. O tratamento com 2,5% de farinha de chia apresentou intenção de compra semelhante ao padrão para ambos os casos. A adição de farinha de chia na elaboração de pães sem glúten sem goma e gordura resultou em um produto que pode ser uma alternativa de alimento saudável para o consumidor celíaco, porém sugerem-se mais estudos que busquem a melhoria dos parâmetros de textura dos pães.
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Estudo de populações do psilídeo-de-concha Glycaspis brimblecombei (Hemiptera: Psyllidae) e de seu parasitóide Psyllaephagus bliteus (Hymenoptera: Encyrtidae) em floresta de Euclyptus camaldulensis por dois métodos de amostragemFerreira Filho, Pedro José [UNESP] 16 December 2005 (has links) (PDF)
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ferreirafilho_pj_me_fca.pdf: 738586 bytes, checksum: 866f186ef0a9be94a392e155c2cf52e2 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Empresa Privada / Os psilídeos são um grupo de pragas amplamente distribuídas, causando perdas consideráveis em sistemas agrícolas e florestais. A recente descoberta da ocorrência do psilídeo-de-concha Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), no Brasil tornou-se um problema de grande importância, por ser específico de Eucalyptus. O parasitóide Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) é indicado como principal agente no controle biológico desta praga. Portanto, para o monitoramento adequado de ambas espécies é necessário um método eficiente de amostragem. Devido a sua importância econômica, esse trabalho objetivou estudar as populações de G. brimblecombei e de P. bliteus em floresta de Eucalyptus camaldulensis por dois métodos de amostragem, utilizando armadilhas amarelas e coleta de folhas para determinação de sua distribuição espacial, flutuação populacional, a relação com fatores meteorológicos (temperatura e precipitação), proporção sexual, e correlacionar os métodos de amostragem com ambas populações. A determinação da distribuição espacial, flutuação populacional, proporção sexual e correlação dos métodos de amostragem (53 armadilhas amarelas e 53 ramos/avaliação) foi realizada em um talhão de 19 ha com E. camaldulensis em Luiz Antônio, SP, com 10 avaliações, entre janeiro e junho de 2005. Concluiu-se que as populações de ambas espécies apresentaram distribuição espacial agregada, possue correlação inversamente proporcional à temperatura, independente do método de amostragem; não foi constatado correlação entre ambas espécies e a precipitação pluviométrica, as armadilhas adesivas amarelas são viáveis como método de amostragem e a proporção sexual (macho : fêmea) foi baixa para populações de G. brimblecombei e alta para populações de P. bliteus, sendo coletados mais fêmeas que machos para ambas espécies, no período avaliado. / Psyllids are a widespread group of pests, causing severe damage on agricultural and forestry systems. The recent discovery about occurrence of red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), in Brazil is nowadays a great problem in Eucalyptus forests, mainly in E. camaldulensis. The psyllid specific parasitic wasp Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is this pest main biological control agent. Thus, the adequate monitoring of both species by a efficient sampling method would facilitate a future decision making. Due to its economic importance, this study aimed to evaluate G. brimblecombei and P. bliteus populations in Eucalyptus camaldulensis plantation by two sampling methods, using yellow traps and foliage samples to determinate their spatial distribution, population fluctuation with weather interactions (temperature and rainfall) and sexual rate and to correlate sampling methods with both populations. The study of the populational fluctuation, the sexual rate, the spatial distribution and correlation sampling methods (53 traps sampled and 53 branches sampled per sampling dates) was carried out on E. camaldulensis plantations in a 19 ha area in Luiz Antônio municipality (SP, Brazil), between January and June, 2005 (10 sampling dates). This research indicated that population of both species noticed special aggregated distribution, inversely proportional correlation subject to temperature. However between sampling methods, there was no correlation between both species with the rainfall, yellow stick traps were useful as sampling methods, sexual rate (male:female) is low to G. brimblecombei populations and high to P. bliteus populations, have been collected more female than male to both species in the evaluated period.
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Estudo de blendas poliméricas constituídas por goma xantana e poli (álcool vinílico) reticuladas com ácido cítrico para aplicação em sistemas de liberação controlada de fármacosSilva, Ingrid Dantas Vasconcelos da 25 February 2016 (has links)
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Previous issue date: 2016-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Polymer blends are a prompt and economical way to obtain new materials and have attracted considerable interest. Xanthan gum (GX) and poly (vinyl alcohol) (PVA) are polymers of great interest because of their properties. The high hydrophilic nature of these materials limits their applications, so they need to be submitted to the crosslinking process. In this work were prepared and characterized polymeric films (1% w / v) consisting of xanthan gum and poly (vinyl alcohol) without crosslinking agent and crosslinked with citric acid (CA) by casting for use in controlled drug release. The infrared analysis demonstrated possible interactions between the polymers in the blend and the incorporation of crosslinker into the polymer matrix. The scanning electron microscope revealed that the surfaces of the films are smooth and homogeneous even with the addition of crosslinking agent. The solubility, swelling and permeability to water vapor tests showed synergism between properties of polymers in the blend and citric acid attributed to the film water resistance. The compositions are stable in an inert atmosphere (N2), and films crosslinked with citric acid exhibited better thermal stability when compared with no crosslinking. The thermal degradation kinetics study complemented the results of thermal analysis showing that the PVA films are more stable and the crosslinking agent has improved thermal properties of the films. Biodegradability tests in soil revealed greater degradation to the polymer blends over a period of 160 days. The films exhibited no antimicrobial activity against the microorganisms studied. The application of crosslinked films with citric acid on controlled drug release showed that acetaminophen, propranolol and fluconazole release mechanism was controlled primarily by diffusion, swelling and relaxation of the polymer chains, with constant release profiles for 24 h, demonstrating that the developed films are promising materials for controlled drug release. / Blendas poliméricas representam uma forma rápida e econômica para obtenção de novos materiais e vêm atraindo bastante atenção. A goma xantana (GX) e o poli (álcool vinílico) (PVA) são polímeros de interesse devido as suas propriedades. O alto caráter hidrofílico desses materiais limitam suas aplicações, por isso eles precisam passar pelo processo de reticulação. Neste trabalho foram preparados e caracterizados filmes poliméricos (1% m/v) constituídos por goma xantana e poli (álcool vinílico) sem agente reticulante e reticulados com ácido cítrico (AC) pelo método da evaporação do solvente para aplicação na área de liberação controlada de fármacos. Os dados de espectroscopia de infravermelho sugeriram possíveis interações entre os polímeros na blenda e a incorporação do reticulante na matriz polimérica. A microscopia eletrônica de varredura revelou que as superfícies dos filmes são lisas e homogêneas, mesmo com a adição do agente reticulante. Os ensaios de solubilidade, intumescimento e permeabilidade ao vapor de água mostraram o sinergismo das propriedades dos polímeros na blenda e que o ácido cítrico atribuiu aos filmes resistência à água. As composições mostraram-se estáveis em atmosfera inerte (N2), e os filmes reticulados com ácido cítrico exibiram melhor estabilidade térmica quando comparados com os sem reticulante. O estudo de cinética de degradação térmica complementou os resultados de análise térmica mostrando que os filmes de poli (álcool vinílico) são mais estáveis e que o agente reticulante aumentou as propriedades térmicas dos filmes. Os ensaios de biodegradabilidade em solo mostraram maior degradação para as blendas poliméricas em um período de 160 dias. Os filmes não demonstraram atividade antimicrobiana frente aos microrganismos estudados. A aplicação dos filmes reticulados com ácido cítrico na área de liberação controlada mostrou que o mecanismo de liberação de paracetamol, propranolol e fluconazol foi controlado principalmente por difusão, intumescimento e relaxamento das cadeias poliméricas, apresentando perfis de liberação constantes em 24 h, demonstrando que os filmes desenvolvidos são materiais promissores para liberação controlada de fármacos.
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Obten??o de novos derivados de ?-naftol e cardanol hidrogenado e avalia??o dos seus efeitos antioxidativos em gasolina automotivaDantas, Michelle Sinara Greg?rio 14 October 2005 (has links)
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Previous issue date: 2005-10-14 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The chemical nature of the hidrocarbons found in gasoline directly affects the formation of oxidation complexes known as gums. Such complexes are slightly soluble in gasoline and their formation is delayed with the use of inhibitors, known as antioxidants. In this study, a synthetic compound (βnaphtol) and a natural subproduct (hydrogenated cardanol, derived from cashewnut shell liquid CNSL) have been used in order to generate novel antioxidant substances. These compounds were submitted to chemical reactions including alkylation, nitration and reduction, with the purpose of forming the following derivatives: 6(Nethyl,Nethylamino)βnaphtol (AO1); 6(Nethyl,Ndiethylamino)βnaphtol (AO2); aminoβnaphtol (AO3); 2(Nethyl,Nethylamino)pentadecylphenol (AOC1), 2(Nethyl,Ndiethylamino)pentadecylphenol (AOC2) and aminopentadecylphenol (AOC3). The derivatives were subjected to accelerated oxidative stability assays (Potential Gum and Induction Period) and to storage assays (Washed Gum and ASTM Color) during six months, with naphtha provided by the petroleum refinery RPBC (Refinaria Presidente Bernardes de Cubat?o, in Brazil). The results for the derivatives were compared to those for commercial additives [DBPC (2,6ditbutyl4methylpcresol) and PDA (N,N disecbutylpphenylenediamine)], which were also added to the naphtha produced at RPBC at the moment of sampling. From all tested antioxidants, the novel antioxidant AOC1 (derived from hydrogenated cardanol) yielded a better global performance. During the period of time in which the naphtha was stored, an examination of this material was carried out in parallel, using the mass spectrometry technique. This study allowed to monitor the formation of a triolefinic compound, as well as the observation of subsequent formation and rupture of the olefinic constituents. As an eventual result from these experimental investigations, a reaction route leading to gum formation has been suggested / O tipo de hidrocarboneto presente na gasolina influencia diretamente na forma??o de complexos de oxida??o conhecidos como goma. Estes complexos s?o levemente sol?veis em gasolinas e sua forma??o ? retardada atrav?s de uso de inibidor, conhecido como antioxidante. Neste estudo utilizouse um composto de origem sint?tica (βnaftol) e um subproduto natural (cardanol hidrogenado (derivado do l?quido da castanha de caju (LCC)) para obten??o de novas subst?ncias antioxidantes. Os compostos citados foram submetidos a rea??es qu?micas de alquila??o, nitra??o e redu??o para obten??o dos seguintes derivados : 6(Netil,Netilamino)βnaftol (AO1), 6(Netil,Ndietilamino)βnaftol (AO2), Aminoβnaftol (AO3), 2(Netil,Netilamino)pentadecilfenol (AOC1), 2(Netil,Ndietilamino)pentadecilfenol (AOC2) e Aminopentadecilfenol (AOC3). Os novos derivados foram submetidos a ensaios acelerados de estabilidade oxidativa (Goma Potencial e Per?odo de Indu??o) e a testes de estocagem (Goma Lavada e Cor ASTM) durante seis meses com nafta amostrada na RPBC (Refinaria Presidente Bernardes de Cubat?o). Os resultados com os novos derivados foram comparados ?queles obtidos com aditivos comerciais [DBPC (2,6diterbutil (4 metil)pcresol) e PDA (N,N disecbutilpfenilenodiamina)]que tamb?m foram adicionados ?s naftas da RPBC no momento da amostragem. O novo antioxidante AOC1(derivado do cardanol hidrogenado) apresentou melhor desempenho global dentre todos os antioxidantes amostrados. Durante o per?odo em que as naftas amostradas foram estocadas, foi realizado, em paralelo, um acompanhamento deste material atrav?s da t?cnica de Espectrometria de Massas e registrouse, n?o somente, a forma??o de um composto triolef?nico, como tamb?m acompanhouse as forma??es e as rupturas, subseq?entes, de compostos olef?nicos. Este acompanhamento possibilitou a sugest?o de uma rota reacional que leva ? forma??o de goma
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