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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Caracterização química de feijão para produção de material de referência certificado / Chemical characterization of beans for production of certified reference material

Lilian Seiko Kato 08 September 2014 (has links)
Alimento base da dieta dos brasileiros, o feijão é a leguminosa de maior importância para consumo direto no mundo. Inúmeras pesquisas em relação às propriedades nutricionais do feijão comum e também do feijão de corda têm sido realizadas, no intuito de avaliar sua composição centesimal, mineral e fatores antinutricionais. Em relação à qualidade das determinações analíticas, sabe-se que os materiais de referência certificados (CRMs) estão se tornando cada vez mais necessários em procedimentos de medição. Contudo, ainda há escassez de CRMs para atender às demandas em todos os setores produtivos, especialmente na agricultura. O domínio da tecnologia para sua produção representa, portanto, um avanço estratégico, por colocar o país em condições de fornecer materiais específicos às próprias necessidades. Dessa forma, este trabalho envolveu a primeira etapa para elaboração de um material de referência certificado de feijão, com a caracterização química e nutricional dos principais tipos comerciais disponíveis no mercado, das espécies Phaseolus vulgaris L. (feijão comum) e Vigna unguiculata (feijão caupi), buscando atender demandas metrológicas específicas da pesquisa e da indústria alimentícia. Foram coletadas 55 amostras de feijão de dez tipos comerciais diferentes no varejo da cidade de Piracicaba. Determinaram-se os elementos químicos Br, Ca, Co, Cs, Fe, K, Mo, Na, Rb, Sc e Zn utilizando análise por ativação neutrônica, a composição centesimal empregando metodologia preconizada pela AOAC e o fator antinutricional ácido fítico segundo o método descrito por Grynspan e Cheryan (1989). Os resultados mostraram diferença significativa entre os tipos comerciais de feijão (p<0,05) para Br, Cs, Co, K, Mo, Na e Zn, e também para os teores de proteínas, cinzas, umidade e ácido fítico. O feijão fradinho, da espécie Vigna unguiculata, apresentou diferenças consideráveis em relação ao feijão comum da espécie Phaseolus vulgaris L., tendo a maior concentração média de Na e as menores concentrações médias de Ca, Co, K e cinzas (p<0,05). O feijão preto apresentou as maiores concentrações médias de Ca, Co, Fe, proteínas e ácido fítico, enquanto o feijão cavalo as maiores concentrações médias de K, Mo e Zn (p<0,05). O feijão carioca apresentou valores médios próximos à média global para todos os parâmetros avaliados, exceto para ácido fítico. Alta variabilidade foi identificada para Br, Cs, Mo, Na, Rb e Sc dentro de um mesmo tipo comercial, enquanto baixa variabilidade foi observada para K, Zn, cinzas e proteínas. O conjunto de dados resultantes da caracterização química das 55 amostras de feijão mostra que os tipos comerciais carioca, preto e fradinho são os mais indicados para produção de material de referência certificado. Considerando o critério de comutatividade, o feijão carioca pode ser utilizado para produzir um material de referência que represente todos os tipos comerciais estudados / Basic food of the Brazilian diet, beans are the most important leguminous for direct consumption in the world. Numerous researches on the nutritional properties of common bean and string bean have been performed in order to assess their centesimal and mineral composition as well the antinutritional factors. Regarding the quality of the analytical determinations, it is known that the certified reference materials (CRMs) are becoming increasingly necessary in measurement procedures. However, there is still lack of CRMs to meet the demands from all productive sectors, especially agriculture. Mastering the technology for their production therefore represents a strategic step forward, to put the country in a position to provide specific materials to own needs. Thus, this work involved the first step in developing a bean certified reference material, with chemical and nutritional characterization of the main commercial types available in the market, from the species Phaseolus vulgaris L. (common bean) and Vigna unguiculata (cowpea), meeting the specific metrological demand of research and food industry. In the retail market of the city of Piracicaba, 55 bean samples from ten different commercial types were collected. The chemical elements Br, Ca, Co, Cs, Fe, K, Mo, Na, Rb, Sc and Zn were determined by nêutron activation analysis, the proximate composition using methodology recommended by the AOAC and the anti-nutritional factor phytic acid, according to the method described by Grynspan and Cheryan (1989). The results showed significant differences between commercial bean types (p<0.05) for Br, Cs, Co, K, Mo, Na and Zn, and also for protein, ash, moisture and phytic acid. The black-eyed pea from Vigna unguiculata species showed considerable differences from the common bean Phaseolus vulgaris L. species, having the highest average concentration of Na and the lowest average concentrations of Ca, Co, K and ash (p<0.05). The black bean had the highest average concentrations of Ca, Co, Fe, proteins and phytic acid, while horse bean the highest average concentrations of K, Mo and Zn (p<0.05). The common bean showed mean values close to the global average for all parameters, except for the phytic acid. High variability has been identified for Br, Cs, Mo, Na, Rb and Sc within a commercial type, while low variability was observed for K, Zn, ash, and proteins. The data set resulting from the chemical characterization of 55 samples indicates that the commercial types common bean, black bean and black-eyed pea are more indicated for the production of the certified reference material. Considering the commutability criteria, the common beans could be used to produce a reference material representative of all commercial types studied
32

Amélioration de la production halieutique des trous traditionnels à poissons (whedos) du delta de l’Ouémé (sud Bénin) par la promotion de l’élevage des poissons-chats Clarias gariepinus et Heterobranchus longifilis

IMOROU TOKO, Ibrahim 19 December 2007 (has links)
La présente étude s’inscrit dans une approche perspective d’augmentation de la production halieutique nationale par l’amélioration des techniques piscicoles déjà existantes, notamment les trous traditionnels à poissons (whedos), dans le delta du fleuve Ouémé (sud Bénin). Les premières approches de nos investigations montrent que, sur le plan socio-économique, l’augmentation de la productivité des whedos s’avère nécessaire pour l’amélioration des conditions de vie des pêcheurs dans la Vallée de l’Ouémé. En effet, avec le mode actuel de gestion des whedos, le revenu net par hectare et par an peut varier entre 182.000 et 572.000 Fcfa. Il représente au niveau actuel environ 27 % des revenus totaux de la pêche par ménage. Cependant, avec la mise en charge et l’alimentation artificielles d’espèces piscicoles adaptées, telles que les poissons-chats Clarias gariepinus et Heterobranchus longifilis, des rendements annuels de 3 à 36 t ha-1 peuvent être obtenus en fonction des densités d’élevage (respectivement de 4 à 24 poissons m-3). Les revenus nets provenant d’une telle gestion sont assez importants et peuvent varier en fonction de la densité de mise en charge, entre 1.664.000 et 31.675.000 Fcfa (respectivement de 4 à 24 poissons m-3). Ainsi, bien que la densité de 10,5 poissons m-3 soit apparue comme étant idéale pour l’optimisation des performances zootechniques, la recherche du profit maximal nous amène à suggérer pour la promotion de l’élevage de C. gariepinus dans les whedos, l’utilisation des densités plus élevées (environ 24 poissons m-3) afin de maximiser leurs capacités de production. Par ailleurs, la nécessité de production massive d’alevins de ces poissons-chats s’est avérée indispensable pour la promotion effective de leur élevage en whedos. A cet effet, nous avons évalué quelques aspects de l’élevage larvaire de ces espèces (âge de sevrage et densité de stockage), de même que les effets zootechniques et nutritionnels de différents régimes à base des tourteaux de soja et de coton aussi bien chez les larves que les juvéniles. Il ressort de ces études que le sevrage des larves de H. longifilis, maintenues à des densités de 10 à 25 individus L-1, est nécessaire entre les jours 5 et 8 post-éclosion afin d’optimiser aussi bien les performances zootechniques qu’économiques de l’élevage. D’autre part, le tourteau de soja s’est avéré plus efficace que celui de coton aussi bien chez les larves que les juvéniles de ces poissons-chats. Cependant, la présence des facteurs antinutritionnels, notamment l’acide phytique, limite les niveaux d’utilisation de ces tourteaux dans les régimes, étant donné que chez les juvéniles des réductions significatives des teneurs corporelles en minéraux, notamment en P, Zn et Mn ont été observées avec les régimes contenant jusqu’à 60 % de ces tourteaux. The present study aims to appraise the perspectives to increase the national fish production by improving the existing fish production systems, as the traditional fish pond (whedos), in the Ouémé River delta (southern Benin). The first approaches of our investigations show that, on the socio-economic level, the increase in the productivity of the whedos seems necessary to improve the livelihood conditions of the fishermen in the Ouémé Valley. Indeed, with the current mode of management of these whedos, we have observed that the net income per hectare can vary between 182,000 and 572,000 Fcfa. It represents, at the current level, approximately 27 % of the total incomes of fishing per household. However, by artificial stocking with adapted fishes, such as the catfishes Clarias gariepinus and Heterobranchus longifilis, and feeding, the annual outputs from 3 to 36 t ha-1 can be reached according to the stocking densities (from 4 to 24 fish m-3, respectively). The nets incomes generated from such management are rather important and can vary according to the stocking densities from 1,664,000 to 31,675,000 Fcfa (from 4 to 24 fish m-3, respectively). Although the density of 10.5 fish m-3 seemed ideal for the optimization of zootechnical parameters, the search of maximum profit leads us to suggest the higher densities (approximately 24 fish m3) for rearing African catfish in the whedos. Moreover, to improve the knowledge of these catfishes fingerlings production, we evaluated some aspects of the larval rearing (weaning time and stocking density), just as the nutritional effects of various diets, based on soybean or cottonseed meals, in the larvae as well as in the juveniles. It arises from these studies that, the weaning of H. longifilis larvae maintained at the densities from 10 to 25 L-1, is necessary between days 5 and 8 posthatch in order to optimize the zootechnical and economical performances of the rearing. Furthermore, we have observed that soybean meal was more effective than cottonseed meal in the larvae as well as in the juveniles. However, the presence of antinutrients factors, particularly the phytic acid, limit the levels of inclusion of these oilseed meals in the diets, since in juveniles, significant reductions of the body minerals contents, particularly P, Zn and Mn, were observed with the diets containing up to 60 % of these plants ingredients.
33

Características agronômicas, nutricionais e tecnológicas de grãos de feijão carioca armazenados, cultivados em sistemas orgânico e convencional / Agronomic, nutritional and technological characteristics of carioca beans grains stored, cropped in organic and conventional systems

Cassol, Flavia Danieli Rech 10 February 2017 (has links)
Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2017-09-05T17:45:54Z No. of bitstreams: 2 FLÁVIA_CASSOL2017.pdf: 1685226 bytes, checksum: 8f79384919a244c9ef937f3069f3c88d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-05T17:45:54Z (GMT). No. of bitstreams: 2 FLÁVIA_CASSOL2017.pdf: 1685226 bytes, checksum: 8f79384919a244c9ef937f3069f3c88d (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The consumption of functional foods, such as beans, has brought important benefits to health, consequently, there is an increasing demand for organic products, which are considered healthier. However, due to the genetic variability of this crop, it is necessary to evaluate it in the field then determine which cultivars are most adapted to different cropping managements, as well as establish the quality attributes involved in the preservation of this leguminous. Thus, this trial aimed at evaluating the agronomic characteristics of carioca beans, cropped in organic and conventional systems, indicating which cultivars are most adapted to each system as well as characterizing the cooling storage effect and in uncontrolled environmental conditions, in order to preserve nutritional and technological characteristics of these grains. Multivariate techniques were applied to determine which variables influenced most on beans quality, and to verify similarities between conservation methods and how carioca beans were produced. Eight carioca bean cultivars were sown in the organic and conventional systems, and the correlation between the production and yield components was evaluated. The studied cultivars were evaluated when freshly harvested (S); and after 180 storage days under refrigeration (R) and environmental conditions (A); according to the nutritional characteristics: protein (Ptn), calcium (Ca), iron (Fe), phosphorus (P), phytic acid (Fit), tannins, antioxidant capacity (DPPH) and technologic characteristics: grain mass (GM), water content (WC), electrical conductivity, grain color (L*, a*, b*, H * and C *) and sphericity, texture, cooking time (CT) and hydration capacity (HC). According to yield, cultivars such as Andorinha, Curió, Estilo, Emperador and Notável were more adapted to the organic cropping, while all the tested cultivars, except Curió, can be indicated to the conventional cropping. The variables that showed the highest correlation with yield were the number of pods in organic beans and plant height in the conventional ones. The cooling storage preserved the technological quality of organic beans, increased the antioxidant capacity and kept higher amount of iron in beans. It also contributed to phosphorus decrease and the significant increases of Fit and tannins, considered antinutritional factors. Campos Gerais beans is a cultivar from IAPAR that showed the best results on quality preservation after six months of storage. According to these data, the main and cluster components (APC) were analyzed. Thus, variables such as Ptn, Ca, P, Fit, tannins, DPPH, CH, TC, MG and H * influenced most beans quality, and were defined according to APC use. Based on the use of Cluster, it is possible to classify cultivars into groups and verify that the refrigerated storage was effective in maintaining their quality. In addition, this technique showed the similarity between organic and conventional beans that belonged to the same cultivar. / O consumo de alimentos funcionais, como o feijão, traz benefícios importantes para a saúde. A procura por produtos de origem orgânica, considerados mais saudáveis, tem, também, contribuído para o aumento no seu consumo. No entanto, devido à variabilidade genética dessa cultura, faz-se necessária sua avaliação no campo, para determinar os cultivares mais adaptados a diferentes formas de cultivo e estabelecer os atributos de qualidade envolvidos na preservação dessa leguminosa. Nesse sentido, os objetivos desta pesquisa foram: avaliar as características agronômicas de feijão carioca, cultivado em sistema orgânico e convencional, indicar os cultivares mais adaptados a cada sistema e caracterizar o efeito do armazenamento refrigerado e em condições ambientais não controladas, na preservação das características nutricionais e tecnológicas desses grãos, usando técnicas multivariadas para determinar as variáveis que mais influenciam na qualidade dos feijões e verificar semelhanças entre as formas de conservação e modo de produção dos feijões carioca. Foram semeados oito cultivares de feijão carioca nos sistemas orgânico e convencional para avaliar a correlação entre as componentes da produção e a produtividade. Após a colheita, os cultivares foram avaliados recém-colhidos (S) e depois de 180 dias de armazenamento, em condições refrigeradas (R) e ambientais (A), quanto às características nutricionais: proteína (Ptn), cálcio (Ca), ferro (Fe), fósforo (P), ácido fítico (Fit) e taninos, capacidade antioxidante (DPPH) e tecnológica: massa de grãos (MG), teor de água (Ta), condutividade elétrica, coloração dos grãos (L*, a*, b*, H* e C*), esfericidade, textura, tempo de cocção (TC) e capacidade de hidratação (CH). De acordo com a produtividade, os cultivares Andorinha, Curió, Estilo, Imperador e Notável mostraram-se mais adaptados ao cultivo orgânico, enquanto todos os cultivares testados, exceto Curió, podem ser indicados ao cultivo convencional. As variáveis que mostraram maior correlação com a produtividade foram o número de vagens nos feijões orgânicos e a altura da planta, no sistema convencional. Nos feijões orgânicos, o armazenamento refrigerado preservou a qualidade tecnológica, aumentou a capacidade antioxidante e manteve maior a quantidade de Fe dos grãos, além de contribuir para a diminuição do P e o aumento significativo dos Fit e taninos, considerados fatores antinutricionais. Os feijões do cultivar IAPAR Campos Gerais foram os que melhor preservaram a qualidade após o armazenamento de 180 dias. Diante desses dados, foram realizadas análises dos componentes principais (APC) e de agrupamento (Cluster). As variáveis que mais influenciaram a qualidade dos feijões foram definidas com o uso da APC, sendo elas Ptn, Ca, P, Fit, taninos, DPPH, CH, TC, MG e H*. Com a utilização do Cluster, é possível classificar os cultivares em grupos e verificar que o armazenamento refrigerado foi eficaz na manutenção da qualidade. Além disso, essa técnica mostrou a semelhança entre os feijões orgânicos e convencionais pertencentes ao mesmo cultivar.

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