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Obtenção de concentrado proteico do farelo de arroz e avaliação das propriedades químicas e funcionaisBernardi, Silvia 29 July 2015 (has links)
Esta dissertação é composta por 5 artigos. / CNPq / INTRODUÇÃO E OBJETIVOS: O arroz é um dos cereais mais consumidos no mundo e durante o seu beneficiamento, obtém-se o farelo que representa cerca de 8% do peso total do grão. O farelo de arroz desengordurado contém aproximadamente 15% de proteínas de alto valor nutricional. As técnicas de extração permitem além de extrair, selecionar e separar e determinadas substâncias. A extração das proteínas do farelo de arroz em meio alcalino é muito utilizada porque neste pH sua solubilidade é máxima e há a ruptura das paredes celulares. Podem ser usados métodos mecânicos e não mecânicos. A agitação mecânica com a movimentação de líquidos por meio de impulsores giratórios auxilia no rompimento das paredes celulares durante processos de extração. A extração assistida por ultrassom (EAU) utiliza frequências acima de 20 kHz para gerar cavitação em meios líquidos, que nada mais é que o colapso de microbolhas de gás e vapor que ocorre quando as mudanças de pressão no meio são grandes o suficiente, para literalmente dilacerá-lo sob a influência do ultrassom. Com este colapso, há o rompimento celular e a transferência de massa para o meio. Um concentrado de proteína do farelo de arroz (CPFA) deve ter boa solubilidade, propriedades funcionais apropriadas, características organolépticas aceitáveis para serem utilizados como um ingrediente alimentar, e possuir aminoácidos essenciais. Os objetivos deste trabalho foram avaliar os efeitos do pH, temperatura, velocidade da agitação, tempo de agitação, tempo em banho ultrassônico e amplitude da potência na extração das proteínas do farelo de arroz, além de analisar a cor, funcionalidade do CPFA (capacidade de absorção de água e óleo, formação de espuma, estabilidade da espuma, capacidade emulsificante, estabilidade da emulsão e formação de gel), solubilidade, perfil de aminoácidos e sua aceitabilidade quando aplicado em suco de caju. MÉTODOS ─ Verificou-se o rendimento proteico em três tipos de extração alcalina: agitação, banho ultrassônico a 37 kHz e banho ultrassônico a 80 kHz. Numa primeira etapa, aplicou-se o planejamento fatorial fracionário 24-1 (com dois níveis, três repetições no ponto central), totalizando 11 ensaios, tendo como variáveis independentes para a extração com agitação: pH, tempo de agitação (min), velocidade da agitação (rpm) e temperatura (ºC), e para a extração em banho de ultrassom (37 e 80 kHz): pH, tempo de ultrassom (min), temperatura (ºC) e amplitude da potência (%). Na segunda etapa, as variáveis com efeitos significativos (p < 0,05) de cada tipo de extração foram submetidas ao Delineamento Composto Central Rotacional (DCCR) 22 (quatro pontos axiais, três repetições no ponto central), totalizando 11 ensaios. As variáveis dependentes, resposta experimental e predita, foram expressas em g.100 mL-1 de extrato ± desvio padrão médio. Os efeitos foram validados pela Análise de Variância, por meio do software Statistica 8.0, sendo considerada a melhor condição de extração aquela com maior teor proteico e desta, obtido o concentrado. O teor de proteína bruta foi determinado por Kjeldahl e multiplicado por 5,95, e o rendimento, razão do conteúdo total da proteína no farelo de arroz pelo encontrado no CPFA. A cor do concentrado extraído por agitação e por ultrassom foi verificada por colorimetria instrumental e deste último método de extração, determinou-se a composição centesimal (%), minerais (µg.g-1), proteínas solúveis (%), capacidade de absorção de água e óleo (g de água.g-1 de amostra; g de óleo.g-1 de amostra), capacidade de formação de espuma (%), estabilidade da espuma (%), capacidade emulsificante (%), estabilidade da emulsão (%) e capacidade de formar gel, perfil de aminoácidos (g.100 g-1). A aplicabilidade foi verificada por avaliação sensorial de suco de caju (ordenação por preferência e aceitabilidade dos atributos: sabor, cor, aroma e impressão global). PRINCIPAIS RESULTADOS ─ A resposta ótima na extração alcalina com acompanhamento de agitação foi do teor de proteína de 48,53 % (b.s.), em pH 10, velocidade de agitação de 80 rpm, tempo de agitação de 300 min e temperatura de 45 ºC, representando o rendimento de 34,51% na extração. A interação entre as variáveis independentes pH, tempo de agitação e temperatura promoveram efeitos favoráveis para a técnica de extração das proteínas, enquanto que a velocidade de agitação não interfere de modo significativo. O planejamento experimental utilizado foi adequado para estudar os efeitos da associação da agitação mecânica ao processo de extração alcalina das proteínas do farelo de arroz. Nessas condições, o CPFA obtido apresentou forma de pó fino e textura aveludada, com valores de L* de 78,29 ± 0,95, a* -4,97 ± 0,05 e b* 16,51 ± 0,10 para a medida instrumental de cor. Quando se avaliou a extração alcalina associada ao banho ultrassônico, comparou-se o desempenho das frequências de 37 e 80 kHz, comprovou-se que na menor frequência houve maior extração. No ensaio com maior rendimento obteve-se um concentrado proteico com teor de proteína de 83,36% (b.s.), quando utilizado o pH 10, 30 min de ultrassom, 100% de amplitude da potência (30ºC) representando um rendimento de 4,74 % na extração. Portanto, a extração assistida pode ultrassom ser utilizada como um método alternativo para extrair proteínas do farelo de arroz, reduzindo o tempo de extração e consumindo menos energia. A EAU é uma técnica promissora e avançada para a extração de substâncias de interesse alimentar, oferecendo potencial para o desenvolvimento de novos produtos. O CPFA apresentou-se na forma cristalina com valores de L* de 60,42 ± 2,15, a* -1,31 ± 0,53 e b* 20,29 ± 1,39 para a medida instrumental de cor, observou-se menor solubilidade em pH 2, 3, 4 e 5, e maior solubilidade na faixa de pH 6 a 10. A capacidade de absorção de água e de óleo de 1,04 ± 0,07 g.g-1, e 11,75 ± 0,67 g.g-1, respectivamente, superior ao da referência Albumina Bovina Sérica (BSA). A maior quantidade de espuma formada ocorreu em pH 4 e 8 (41,17% ± 2,30; 48,47% ± 1,15) e menor em pH 6 (9,96% ± 0,00), porém a estabilidade das espumas formadas foi baixa em todos os pHs, e em ambos os casos, a BSA apresentou característica espumante superior. CPFA apresentou boa capacidade emulsificante em pH 2, 4, 6 e 8 (56,20% ± 5,39; 66,19% ± 6,57; 67,86% ± 0,19; 72,92% ± 2,95) comparáveis a BSA, mas emulsões menos estáveis em pH 2 (32,50% ± 3,54). Em temperatura de 30 ºC e 8 ºC, o CPFA apresentou baixa capacidade geleificante, com um gel frágil e pouco consistente. O perfil de aminoácidos do CPFA indicou a presença de ácido glutâmico, glicina, histidina, arginina, treonina, valina, metionina, isoleucina, leucina, fenilalanina e lisina, essenciais para a síntese das proteínas. O desempenho sensorial do CPFA foi avaliado em formulações de suco de caju adoçado contendo 0,1%; 0,3% e 0,5% de CPFA e ordenadas de acordo com a preferência de 60 provadores não treinados. Constatou-se que não houve diferença significativa entre as amostras (p > 0,05). Em função deste resultado, um teste de aceitação foi aplicado a 64 provadores não treinados, utilizando uma fórmula de suco de caju adoçado adicionada de 0,5% de CPFA e a Controle (sem CPFA). Verificou-se que houve diferença significativa (p < 0,05) entre as amostras nos atributos cor, sabor, aroma e impressão global. Os provadores gostaram moderadamente do Controle, mas foram indiferentes a fórmula com 0,5% de CPFA, uma vez que acentuou as características sensoriais do arroz ao suco de caju. O CPFA apresentou excelentes propriedades funcionais que o tornam um ingrediente promissor para a indústria alimentícia. / INTRODUCTION AND OBJECTIVES: Rice is the cereal most consumed in the world and during the processing, it is obtained the rice bran which represents 8% of the total weight of the grain. The defatted rice bran contains approximately 15% of protein of high nutritional value. The extraction techniques permit besides to extract, also to select and to separate substances. The extraction of rice bran proteins by alkaline medium is often used because they reach the maximum solubility in the pH and to assist in rupture of cell walls of a food. Mechanical and non-mechanical methods may be used. Mechanical stirring with the movement of liquid through rotating impellers assists in the disruption of the cell walls during extraction processes. The extraction assisted by the ultrasound (EAU) uses frequencies above 20 kHz to generate cavitation in liquids, which is the collapse of microbubbles of gas and vapor that occurs when the pressure changes in the middle are large enough to literally lacerate it under the influence of ultrasound. With this collapse, there is the cell disruption and the mass transfer to the environment. A rice bran protein concentrate (RBPC) should have good solubility, appropriate functional properties, acceptable sensory characteristics to be used as a food ingredient e to have essential amino acids. The objectives of this study were evaluate the effects of pH, temperature, speed of stirring, stirring time, time in ultrasonic bath and amplitude of the power in the extraction of rice bran protein, and analyzing the color, RBPC functionality (water and oil retention capacity, foaming, foam stability, emulsifying capacity, emulsion stability and gel formation), solubility, amino acid profile and its acceptability when applied in cashew juice. METHODS ─ It was verified the protein yield in three types of alkaline extraction: agitation, ultrasonic bath at 37 kHz and ultrasonic bath at 80 kHz. As a first step, it was applied the Fractional Factorial Planning 24-1 (with two levels, three replicates in the central point), totaling 11 trials, with the independent variables for extraction with stirring: pH, agitation time (min), speed stirring (rpm) and temperature (°C) and for the extraction in an ultrasound bath (37 and 80 kHz): pH, ultrasound time (min) temperature (°C) and power range (%). In the second stage, the variables with significant effects (p < 0.05) of each type of extraction were subjected to Design Central Composite Rotational (DCCR) 22 (four axial points, three repetitions at the central point), totaling 11 trials. The dependent variables, the experimental and predicted response were expressed in g.100 mL-1 extract ± average standard deviation. The effects were validated by analysis of variance, using software Statistica 8.0, being considered the best extraction condition one with the highest protein content and thus, obtained the concentrate. The crude protein content was determined by Kjeldahl and multiplied by 5.95. The yield was calculated as the ratio of the total content of protein in rice bran by the one found in the RBPC. The color of the concentrate extracted by stirring and by ultrasound was checked by instrumental colorimetry and from the latter extraction method, it was determined the chemical composition (%), minerals (μg.g-1), soluble protein (%), water and oil retention capacity (g water.g-1 sample; g oil.g-1 sample), foaming capacity (%), foam stability (%), emulsifying capacity (%), stability of emulsion (%), ability to form gel and amino acid profile (g.100 g-1). The applicability was checked by sensory evaluation of cashew juice (preference and acceptability of attributes as taste, color, smell and global impression). MAIN RESULTS ─ The optimal response in the alkaline extraction with monitoring of stirring was of 48.53% protein (DB), at pH 10, stirring speed of 80 rpm, stirring time of 300 min and temperature of 45 °C, representing the yield of 34.51% in extraction. The interaction between the independent variables as pH, stirring time and temperature promoted favorable effects on protein extraction technique while the stirring speed does not interfere significantly. The experimental planning used was adequate to study the effects of the combination of mechanical stirring to alkaline extraction process of rice bran protein. Under these conditions, RBPC obtained presented as a fine powder and velvety texture, with values of L* 78.29 ± 0.95, a* -4.97 ± 0.05 and b* 16.51 ± 0.10 for the instrumental color measurement. When assessing the alkaline extraction associated with the ultrasonic bath, it was compared the performance of the frequencies of 37 and 80 kHz, and it was proved that the lower frequencies have shown higher extraction. In the test with increased yield obtained a protein concentrate with a protein content of 83.36% (DB), when used pH 10, 30 min of ultrasound, 100% power range (30 °C), representing a yield of 4,74% extraction. Therefore, the UAE can be used as an alternative method for extracting rice bran protein, reducing the extraction time and consuming less power. UAE is a promising and advanced technique for extracting substances from food interest, offering potential for the development of new products. The RBPC presented in the crystalline form with values L* 60.42 ± 2.15, a* -1.31 ± 0.53 and b*20.29 ± 1.39 for instrumental measurement of color. It was observed a lower solubility at pH 2, 3, 4 and 5, but greater solubility in the pH range 6 to 10. The water and oil absorption capacity was 1.04 ± 0.07 g.g-1 and 11.75% ± 0.67 g.g-1, respectively, higher to reference Bovine Serum Albumin (BSA). The greater amount of foam was formed in pH 4 and 8 (41.17% ± 2.30, 48.47% ± 1.15) and lower at pH 6 (9.96% ± 0.00), but the stability of the formed foam was low at all pHs and in both cases, and BSA showed higher foaming characteristics. RBPC showed good emulsifying capacity at pH 2, 4, 6 and 8 (56.20% ± 5.39, 66.19% ± 6.57, 67.86% ± 0.19, 72.92% ± 2.95) comparable to BSA, but less stable emulsions at pH 2 (32.50% ± 3.54). In temperature of 30 °C and 8 °C, the RBPC showed low gelling capacity with a fragile gel and little consistent. The amino acid profile of the RBPC presented good amounts of glutamic acid, glycine, histidine, arginine, threonine, valine, methionine, isoleucine, leucine, phenylalanine and lysine, essential for protein synthesis. The sensory performance of the RBPC was evaluated in formulations of sweetened cashew juice containing 0.1%; 0.3% and 0.5% RBPC and ordered according to the preference of 60 untrained panelists. It was observed that there was no significant difference between the samples (p > 0.05). Due to this result, an acceptance test was applied to 64 untrained panelists using a formula of sweetened cashew juice added with 0.5% of RBPC and the control formula (without RBPC). It was found that there was a significant difference (p < 0.05) between samples in attributes as taste, color, smell and overall impression. Tasters liked moderately the control formula, but were indifferent to the formula with 0.5% RBPC because the sensory characteristics of the rice were accentuated. The RBPC presented excellent functional properties that make it a promising ingredient for the food industry. / 5000
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Ferramentas e sistema de custo aplicados a gestão da qualidade no agronegócioTelles, Leomara Battisti 10 September 2014 (has links)
A gestão da qualidade é um fator determinante no sucesso de qualquer empresa, principalmente, do setor alimentício, onde a qualidade está diretamente relacionada à saúde e segurança alimentar. Além disso, uma eficiente gestão da qualidade impacta diretamente nos custos e, consequentemente, na rentabilidade das empresas. Considerando isso, o objetivo deste estudo é investigar o uso de ferramentas e sistema de custos aplicados à gestão da qualidade em laticínios no Sudoeste do Paraná, através da caracterização dos laticínios pesquisados e avaliação da implantação de ferramentas de gestão da qualidade e de sistema de custos da qualidade. Para sua realização os dados foram coletados através de questionário semi estruturado com questões abertas e fechadas aplicado a nove laticínios sob o Serviço de Inspeção Paranaense (SIP) da região Sudoeste do Paraná. Os resultados foram analisados através da estatística descritiva. Através da análise dos dados constatou-se que os laticínios avaliados classificam-se como de micro e pequeno porte, concentrando seus esforços para a implantação das ferramentas e metodologias da gestão da qualidade da “Era” da garantia da qualidade, contudo, ainda há o que melhorar nas “Eras” da verificação e do controle estatístico da qualidade. Com relação aos Sistemas de Custos da Qualidade (SCQ) foi constatado que nenhum laticínio possui a ferramenta totalmente implantada e um percentual de 33,33% encontram-se em processo de implantação. Dos laticínios avaliados, 11% não possuem SCQ implantado e não têm planos de implantação, os demais planejam implantar a médio prazo e indicam que as principais dificuldades de implantação relacionam-se com o desconhecimento da metodologia e na crença da necessidade de altos investimentos. / Quality management is a key factor in the success of any company especially to food industry where quality is directly related to health and food security. Moreover, an efficient quality management impacts directly in the costs and, profitability, in the hence of companies. Based on these, this study aims to investigate the usage of tools and system costs applied to the quality management in dairies of Paraná’s southwest, through the characterization of the researched dairies with focus on the evaluation of the quality management tools implementation and quality expenses systems. To its realization the data that support this research were collected using semi-structured questionnaire with opened and closed questions, applied to nine dairies under the supervision of the Paranaense Inspection Service (SIP) from Paraná’s southwest region. The results were analyzed based on descriptive statistics. From the data analysis it was found that dairies products evaluated are classified as micro and small, focusing their efforts for the implementation of the tools and methodologies of quality management "Era" quality assurance, however, there is still room to the improvement of "Eras" verification and statistical quality control. Regarding the Quality expenses systems (SCQ) it was revealed that no dairy has fully implemented the tool and a percentage of 33.33% lies in the implementation process. From evaluated dairies, 11% have deployed SCQ and have no plans to implement, the others plan to deploy medium term indicating that the main difficulties of implementation are related to the lack of methodology and believes on the need for high investments.
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Obtenção de concentrado proteico do farelo de arroz e avaliação das propriedades químicas e funcionaisBernardi, Silvia 29 July 2015 (has links)
Esta dissertação é composta por 5 artigos. / CNPq / INTRODUÇÃO E OBJETIVOS: O arroz é um dos cereais mais consumidos no mundo e durante o seu beneficiamento, obtém-se o farelo que representa cerca de 8% do peso total do grão. O farelo de arroz desengordurado contém aproximadamente 15% de proteínas de alto valor nutricional. As técnicas de extração permitem além de extrair, selecionar e separar e determinadas substâncias. A extração das proteínas do farelo de arroz em meio alcalino é muito utilizada porque neste pH sua solubilidade é máxima e há a ruptura das paredes celulares. Podem ser usados métodos mecânicos e não mecânicos. A agitação mecânica com a movimentação de líquidos por meio de impulsores giratórios auxilia no rompimento das paredes celulares durante processos de extração. A extração assistida por ultrassom (EAU) utiliza frequências acima de 20 kHz para gerar cavitação em meios líquidos, que nada mais é que o colapso de microbolhas de gás e vapor que ocorre quando as mudanças de pressão no meio são grandes o suficiente, para literalmente dilacerá-lo sob a influência do ultrassom. Com este colapso, há o rompimento celular e a transferência de massa para o meio. Um concentrado de proteína do farelo de arroz (CPFA) deve ter boa solubilidade, propriedades funcionais apropriadas, características organolépticas aceitáveis para serem utilizados como um ingrediente alimentar, e possuir aminoácidos essenciais. Os objetivos deste trabalho foram avaliar os efeitos do pH, temperatura, velocidade da agitação, tempo de agitação, tempo em banho ultrassônico e amplitude da potência na extração das proteínas do farelo de arroz, além de analisar a cor, funcionalidade do CPFA (capacidade de absorção de água e óleo, formação de espuma, estabilidade da espuma, capacidade emulsificante, estabilidade da emulsão e formação de gel), solubilidade, perfil de aminoácidos e sua aceitabilidade quando aplicado em suco de caju. MÉTODOS ─ Verificou-se o rendimento proteico em três tipos de extração alcalina: agitação, banho ultrassônico a 37 kHz e banho ultrassônico a 80 kHz. Numa primeira etapa, aplicou-se o planejamento fatorial fracionário 24-1 (com dois níveis, três repetições no ponto central), totalizando 11 ensaios, tendo como variáveis independentes para a extração com agitação: pH, tempo de agitação (min), velocidade da agitação (rpm) e temperatura (ºC), e para a extração em banho de ultrassom (37 e 80 kHz): pH, tempo de ultrassom (min), temperatura (ºC) e amplitude da potência (%). Na segunda etapa, as variáveis com efeitos significativos (p < 0,05) de cada tipo de extração foram submetidas ao Delineamento Composto Central Rotacional (DCCR) 22 (quatro pontos axiais, três repetições no ponto central), totalizando 11 ensaios. As variáveis dependentes, resposta experimental e predita, foram expressas em g.100 mL-1 de extrato ± desvio padrão médio. Os efeitos foram validados pela Análise de Variância, por meio do software Statistica 8.0, sendo considerada a melhor condição de extração aquela com maior teor proteico e desta, obtido o concentrado. O teor de proteína bruta foi determinado por Kjeldahl e multiplicado por 5,95, e o rendimento, razão do conteúdo total da proteína no farelo de arroz pelo encontrado no CPFA. A cor do concentrado extraído por agitação e por ultrassom foi verificada por colorimetria instrumental e deste último método de extração, determinou-se a composição centesimal (%), minerais (µg.g-1), proteínas solúveis (%), capacidade de absorção de água e óleo (g de água.g-1 de amostra; g de óleo.g-1 de amostra), capacidade de formação de espuma (%), estabilidade da espuma (%), capacidade emulsificante (%), estabilidade da emulsão (%) e capacidade de formar gel, perfil de aminoácidos (g.100 g-1). A aplicabilidade foi verificada por avaliação sensorial de suco de caju (ordenação por preferência e aceitabilidade dos atributos: sabor, cor, aroma e impressão global). PRINCIPAIS RESULTADOS ─ A resposta ótima na extração alcalina com acompanhamento de agitação foi do teor de proteína de 48,53 % (b.s.), em pH 10, velocidade de agitação de 80 rpm, tempo de agitação de 300 min e temperatura de 45 ºC, representando o rendimento de 34,51% na extração. A interação entre as variáveis independentes pH, tempo de agitação e temperatura promoveram efeitos favoráveis para a técnica de extração das proteínas, enquanto que a velocidade de agitação não interfere de modo significativo. O planejamento experimental utilizado foi adequado para estudar os efeitos da associação da agitação mecânica ao processo de extração alcalina das proteínas do farelo de arroz. Nessas condições, o CPFA obtido apresentou forma de pó fino e textura aveludada, com valores de L* de 78,29 ± 0,95, a* -4,97 ± 0,05 e b* 16,51 ± 0,10 para a medida instrumental de cor. Quando se avaliou a extração alcalina associada ao banho ultrassônico, comparou-se o desempenho das frequências de 37 e 80 kHz, comprovou-se que na menor frequência houve maior extração. No ensaio com maior rendimento obteve-se um concentrado proteico com teor de proteína de 83,36% (b.s.), quando utilizado o pH 10, 30 min de ultrassom, 100% de amplitude da potência (30ºC) representando um rendimento de 4,74 % na extração. Portanto, a extração assistida pode ultrassom ser utilizada como um método alternativo para extrair proteínas do farelo de arroz, reduzindo o tempo de extração e consumindo menos energia. A EAU é uma técnica promissora e avançada para a extração de substâncias de interesse alimentar, oferecendo potencial para o desenvolvimento de novos produtos. O CPFA apresentou-se na forma cristalina com valores de L* de 60,42 ± 2,15, a* -1,31 ± 0,53 e b* 20,29 ± 1,39 para a medida instrumental de cor, observou-se menor solubilidade em pH 2, 3, 4 e 5, e maior solubilidade na faixa de pH 6 a 10. A capacidade de absorção de água e de óleo de 1,04 ± 0,07 g.g-1, e 11,75 ± 0,67 g.g-1, respectivamente, superior ao da referência Albumina Bovina Sérica (BSA). A maior quantidade de espuma formada ocorreu em pH 4 e 8 (41,17% ± 2,30; 48,47% ± 1,15) e menor em pH 6 (9,96% ± 0,00), porém a estabilidade das espumas formadas foi baixa em todos os pHs, e em ambos os casos, a BSA apresentou característica espumante superior. CPFA apresentou boa capacidade emulsificante em pH 2, 4, 6 e 8 (56,20% ± 5,39; 66,19% ± 6,57; 67,86% ± 0,19; 72,92% ± 2,95) comparáveis a BSA, mas emulsões menos estáveis em pH 2 (32,50% ± 3,54). Em temperatura de 30 ºC e 8 ºC, o CPFA apresentou baixa capacidade geleificante, com um gel frágil e pouco consistente. O perfil de aminoácidos do CPFA indicou a presença de ácido glutâmico, glicina, histidina, arginina, treonina, valina, metionina, isoleucina, leucina, fenilalanina e lisina, essenciais para a síntese das proteínas. O desempenho sensorial do CPFA foi avaliado em formulações de suco de caju adoçado contendo 0,1%; 0,3% e 0,5% de CPFA e ordenadas de acordo com a preferência de 60 provadores não treinados. Constatou-se que não houve diferença significativa entre as amostras (p > 0,05). Em função deste resultado, um teste de aceitação foi aplicado a 64 provadores não treinados, utilizando uma fórmula de suco de caju adoçado adicionada de 0,5% de CPFA e a Controle (sem CPFA). Verificou-se que houve diferença significativa (p < 0,05) entre as amostras nos atributos cor, sabor, aroma e impressão global. Os provadores gostaram moderadamente do Controle, mas foram indiferentes a fórmula com 0,5% de CPFA, uma vez que acentuou as características sensoriais do arroz ao suco de caju. O CPFA apresentou excelentes propriedades funcionais que o tornam um ingrediente promissor para a indústria alimentícia. / INTRODUCTION AND OBJECTIVES: Rice is the cereal most consumed in the world and during the processing, it is obtained the rice bran which represents 8% of the total weight of the grain. The defatted rice bran contains approximately 15% of protein of high nutritional value. The extraction techniques permit besides to extract, also to select and to separate substances. The extraction of rice bran proteins by alkaline medium is often used because they reach the maximum solubility in the pH and to assist in rupture of cell walls of a food. Mechanical and non-mechanical methods may be used. Mechanical stirring with the movement of liquid through rotating impellers assists in the disruption of the cell walls during extraction processes. The extraction assisted by the ultrasound (EAU) uses frequencies above 20 kHz to generate cavitation in liquids, which is the collapse of microbubbles of gas and vapor that occurs when the pressure changes in the middle are large enough to literally lacerate it under the influence of ultrasound. With this collapse, there is the cell disruption and the mass transfer to the environment. A rice bran protein concentrate (RBPC) should have good solubility, appropriate functional properties, acceptable sensory characteristics to be used as a food ingredient e to have essential amino acids. The objectives of this study were evaluate the effects of pH, temperature, speed of stirring, stirring time, time in ultrasonic bath and amplitude of the power in the extraction of rice bran protein, and analyzing the color, RBPC functionality (water and oil retention capacity, foaming, foam stability, emulsifying capacity, emulsion stability and gel formation), solubility, amino acid profile and its acceptability when applied in cashew juice. METHODS ─ It was verified the protein yield in three types of alkaline extraction: agitation, ultrasonic bath at 37 kHz and ultrasonic bath at 80 kHz. As a first step, it was applied the Fractional Factorial Planning 24-1 (with two levels, three replicates in the central point), totaling 11 trials, with the independent variables for extraction with stirring: pH, agitation time (min), speed stirring (rpm) and temperature (°C) and for the extraction in an ultrasound bath (37 and 80 kHz): pH, ultrasound time (min) temperature (°C) and power range (%). In the second stage, the variables with significant effects (p < 0.05) of each type of extraction were subjected to Design Central Composite Rotational (DCCR) 22 (four axial points, three repetitions at the central point), totaling 11 trials. The dependent variables, the experimental and predicted response were expressed in g.100 mL-1 extract ± average standard deviation. The effects were validated by analysis of variance, using software Statistica 8.0, being considered the best extraction condition one with the highest protein content and thus, obtained the concentrate. The crude protein content was determined by Kjeldahl and multiplied by 5.95. The yield was calculated as the ratio of the total content of protein in rice bran by the one found in the RBPC. The color of the concentrate extracted by stirring and by ultrasound was checked by instrumental colorimetry and from the latter extraction method, it was determined the chemical composition (%), minerals (μg.g-1), soluble protein (%), water and oil retention capacity (g water.g-1 sample; g oil.g-1 sample), foaming capacity (%), foam stability (%), emulsifying capacity (%), stability of emulsion (%), ability to form gel and amino acid profile (g.100 g-1). The applicability was checked by sensory evaluation of cashew juice (preference and acceptability of attributes as taste, color, smell and global impression). MAIN RESULTS ─ The optimal response in the alkaline extraction with monitoring of stirring was of 48.53% protein (DB), at pH 10, stirring speed of 80 rpm, stirring time of 300 min and temperature of 45 °C, representing the yield of 34.51% in extraction. The interaction between the independent variables as pH, stirring time and temperature promoted favorable effects on protein extraction technique while the stirring speed does not interfere significantly. The experimental planning used was adequate to study the effects of the combination of mechanical stirring to alkaline extraction process of rice bran protein. Under these conditions, RBPC obtained presented as a fine powder and velvety texture, with values of L* 78.29 ± 0.95, a* -4.97 ± 0.05 and b* 16.51 ± 0.10 for the instrumental color measurement. When assessing the alkaline extraction associated with the ultrasonic bath, it was compared the performance of the frequencies of 37 and 80 kHz, and it was proved that the lower frequencies have shown higher extraction. In the test with increased yield obtained a protein concentrate with a protein content of 83.36% (DB), when used pH 10, 30 min of ultrasound, 100% power range (30 °C), representing a yield of 4,74% extraction. Therefore, the UAE can be used as an alternative method for extracting rice bran protein, reducing the extraction time and consuming less power. UAE is a promising and advanced technique for extracting substances from food interest, offering potential for the development of new products. The RBPC presented in the crystalline form with values L* 60.42 ± 2.15, a* -1.31 ± 0.53 and b*20.29 ± 1.39 for instrumental measurement of color. It was observed a lower solubility at pH 2, 3, 4 and 5, but greater solubility in the pH range 6 to 10. The water and oil absorption capacity was 1.04 ± 0.07 g.g-1 and 11.75% ± 0.67 g.g-1, respectively, higher to reference Bovine Serum Albumin (BSA). The greater amount of foam was formed in pH 4 and 8 (41.17% ± 2.30, 48.47% ± 1.15) and lower at pH 6 (9.96% ± 0.00), but the stability of the formed foam was low at all pHs and in both cases, and BSA showed higher foaming characteristics. RBPC showed good emulsifying capacity at pH 2, 4, 6 and 8 (56.20% ± 5.39, 66.19% ± 6.57, 67.86% ± 0.19, 72.92% ± 2.95) comparable to BSA, but less stable emulsions at pH 2 (32.50% ± 3.54). In temperature of 30 °C and 8 °C, the RBPC showed low gelling capacity with a fragile gel and little consistent. The amino acid profile of the RBPC presented good amounts of glutamic acid, glycine, histidine, arginine, threonine, valine, methionine, isoleucine, leucine, phenylalanine and lysine, essential for protein synthesis. The sensory performance of the RBPC was evaluated in formulations of sweetened cashew juice containing 0.1%; 0.3% and 0.5% RBPC and ordered according to the preference of 60 untrained panelists. It was observed that there was no significant difference between the samples (p > 0.05). Due to this result, an acceptance test was applied to 64 untrained panelists using a formula of sweetened cashew juice added with 0.5% of RBPC and the control formula (without RBPC). It was found that there was a significant difference (p < 0.05) between samples in attributes as taste, color, smell and overall impression. Tasters liked moderately the control formula, but were indifferent to the formula with 0.5% RBPC because the sensory characteristics of the rice were accentuated. The RBPC presented excellent functional properties that make it a promising ingredient for the food industry. / 5000
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Agro-industrial value chains in developing countries in the era of globalisation : the case of sugarcane in Punjab, PakistanSafdar, Muhammad Tayyab January 2015 (has links)
No description available.
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Strategiese boerderybestuur in 'n veranderende omgewing (Afrikaans)Du Plessis, Ane-Lize 08 September 2005 (has links)
AFRIKAANS: Die 21 ste eeu word deur invloedryke dryfkrragte wat die landboubedryf tot nuwe dimensies dwing gekenmerk. Veranderende omstandighede vereis nuwe vaardighede in bestuur ten einde toenemende uitdagings aan te spreek. Die vermoë van die bestuurder was nog altyd 'n belangrike parameter in landbou. Bestuur se optrede bepaal die sukses of ondergang van enige ondememing, insluitende die boerdery-ondememing. Min studies fokus op die strategiese bestuur van die boerdery-onderneming. Strategiese bestuur is bykans 'n vergete hulpbron. Hierdie studie stel ondersoek in na strategiese bestuur in die boerdery-onderneming. Die fokus is op die sewe bestuurstake van strategiese bestuur: <ul> 1. Formuleer 'n visie en missie. 2. Stel doelwitte. 3. Analiseer die eksteme omgewing. 4. Analiseer die interne omgewing. 5. Formuleer 'n strategie. 6. Implementering en uitvoering van die strategie. 7. Evalueer die prestasie en inisieer regstellende optrede.<br></ul> Hierdie studie is hoofsaaklik onderneem om ondersoek in te stel na die mate waarin die kommersiele boer sy boerdery-onderneming strategies bestuur. Ondersoek word ook ingestel of die kommersiële boer oor voldoende kennis van strategiese bestuur beskik. Hierdie ondersoekende studie van strategiese bestuur in die boerdery-onderneming word deur 'n omvattende literatuurstudie sowel as 'n empiriese ondersoek gerugsteun. Die literatuur gee ' n oorsig oor die landboubedryf se interne omgewing en eksteme omgewing. Strategiese bestuur kom daama onder die soeklig. Vir die doel van hierdie ondersoek is vraelyste en persoonlike onderhoude in die empiriese studie gebruik. Respondente is persoonlik op die plase besoek. Tydens die voltooiing van die vraelyste het die respondente vrae aangaande strategiese bestuur beantwoord. In die persoonlike onderhoude is konsepte verhelder en die bestuursprobleem is gevolglik beter in die persoonlike onderhoude ondervang. Die opname is onder 70 kommersiële boere in die Loskopskema: Marble Hall-streek gedoen. Bevindings dui daarop dat bestuurders me willens en wetens 'n strategie formuleer me. Die strategie kom inkrementeel tot stand. Boere volg 'n meer informele en minder omvattende rigting in die formulering van 'n strategie. Moontlike oorsake vir 'n meer informele strategie is die onstabiele omgewing van die landboubedryf en 'n tekort aan kennis van strategiese bestuur. Daar word aanbeveel dat strategiese bestuur as 'n riglyn gebruik word om by die veranderende omgewing van die landboubedryf aan te pas. Bestuur van die ondememing moet beter beheer en ontwikkel word ten einde by nuwe strategiese rigtings wat ontstaan aan te pas. Die sukses van 'n onderneming word nie deur die implementering en uitvoering van 'n goeie strategie verseker me. Die verantwoordelikheid berus by die bestuur om by veranderende omstandighede aan te pas. 'n Verdedigende strategie moet ondemeem word om teenspoed die hoof te bied. Die logiese grond vir die gebruik van strategiese bestuur is gevolglik dat dit tot beter prestasie sal lei. ENGLISH: Powerful forces are propelling the agricultural industry toward new dimensions for the 21st Century. Changing circumstances in the agricultural sector require new skills to address these challenges. Managerial ability has always been regarded as an important parameter in agricultural production. Managerial behavior is the determining factor that causes a business, including a farm business, to prosper or fail. Few studies have focused on the strategic management of a farm business. Strategic management is almost a forgotten resource. This study is designed to appraise the background of strategic management in a farm business. The emphasis was placed on seven interrelated managerial tasks of strategic management: <ul> 1. Forming a strategic vision and mission. 2. Setting objectives. 3. Analyse the external environment. 4. Analyse the internal environment. S. Crafting a strategy. 5. Implementing and executing the chosen strategy. 6. Evaluating performance and initiating corrective adjustments.<br></ul> The study's main objective is to examine the degree to which the farm business is using a strategic management process effectively in managing its business. At the same time this study investigates if the commercial farmers have sufficient knowledge of the concept of strategic management. This study is investigative of strategic management and is backed by a comprehensive literature review and empirical study. The literature gives an overview of the internal environment and external environment of agriculture and the field of study strategic management is also introduced. The empirical study consists of a questionnaire and personal interviews. Each of the respondents was subsequently visited, and questionnaires were completed regarding aspects of strategic management. Depth and detail of information was secured by a personal interview. The survey involves 70 commercial farmers in the Loskop scheme: Marble Hall-region. Die results of the research indicate that managers do not follow a deliberate strategy but rather an emergency strategy. Strategic direction is not controlled through setting prior, widely shared intention and monitoring outcomes. A possible reason for this phenomenon is the instability of the agricultural environment and the lack of knowledge of strategic management. Recommendations are made on how managers must seek to provoke around the instability of the environment and pressing challenges by using strategic management as a guideline. Managers have to adopt a form of control and development that enables new strategic direction to emerge. Effective strategy combined with effective strategy execution doesn't guarantee the success of a company. It is the responsibility of a company's management to adjust to unexpectedly tough conditions by undertaking strategic defenses and business approaches that can overcome adversity. The rationale for using strategic management is therefore compelling: the better conceived a company's strategy and the more competently it is executed, the more likely it is that the company will be a standout performer and exhibit enviable business practices. / Dissertation (MCom (Business Management))--University of Pretoria, 2005. / Business Management / unrestricted
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Strategies to overcome institutional barriers to the transition from conventional to sustainable agriculture in Canada : the role of government, research institutions and agribusinessMacRae, Roderick John January 1991 (has links)
No description available.
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An institutional economics approach to agribusiness in development : South African case studiesKaraan, Abolus Salam Mohammad 04 1900 (has links)
Thesis (PhDAgric) -- Stellenbosch University, 2006. / ENGLISH ABSTRACT: This dissertation is a sojourn into institutional economics and its application to
contemporary economic and development issues in South Africa. Economic
development initiatives in agribusiness have much to gain from the theories and
approaches advanced by the new institutional economics. Institutions are considered
essential to the functioning of economies, markets and organizations, despite its
neglect in neoclassical economics The study intends to prove that 'institutions matter',
especially when social and economic transformation is necessary. The cases studied
exhibit how institutions matter and shape economic outcomes.
The theoretical basis established in this thesis was applied to economic development
challenges such as contracting, organizational innovation, economic empowerment,
land reform, building social capital, organizational design, supply chain management,
entrepreneurial development, and modes of constructive engagement. The thesis is a
compilation of academic papers applied to the various selected developmental
challenges prevalent in South African agriculture.
The study begins by delving into the more popular New Institutional Economics
literature and specifically transaction cost economics. Somewhat unexpectedly, this
leads to a greater appreciation for the insights generated by the Old Institutionalists in
investigating the nature of institutions. Hence, the old institutional economics gains
prominence in the latter part of this work, contrary to contemporary approaches
followed in agricultural economics. The acknowledgement given to aspects like social
capital and embeddedness is consistent with Williamson's proposed framework for
the economics of institutions and this is used as the conceptual framework in this
thesis.
Whereas the new institutional economics was found to be useful in yielding
knowledge through analysis and remediable outcomes, the old institutional economics
retains its advantage in promoting understanding of problems especially in the face of
complexity. This inclination has influenced the thesis in two ways. First, it diverted
the latter part of the work towards the old institutional economics and the role of
social capital in shaping institutions and economic behaviour. Second, it reverts to theories on the nature of the firm that complements the transaction cost approach. The
transaction costs approach is thus only used where it is found most effective i.e.
analysing vertical integration between firms and the relevant ex ante incentives and
the ex post governance aspects
Most studies are motivated by a general recognition of the role of institutions in
framing economic outcomes and end up in the new institutional economics and
subsequently transactions cost economics. This favouring of the transaction cost
approach has found appeal due to its ability to predict structural and organisational
outcomes such as the efficient boundaries of firms, internal organisation, contractual
relations, incentives, etc. Methodologically, it enables analysts to employ the
empirical and mathematical rigour that has become a feature, but too often the
purpose, of economic research. Three papers are devoted to this approach and elicit
organisational designs that best contend with identified transaction costs.
The study confirms that several aspects matter in institutional analysis when applied
in an economic developmental context such as South Africa. Historical context is
acknowledged as a critical facet of institutional analyses in the sense that institutions
are shaped by the forces of history. Social capital is established as an important
component of institutional economic analysis and particularly relevant in situations
where social capital has been eroded by political economic manipulations. Attending
to social capital require (inter alia) insight into the nature of the societal context,
implied path dependency, the extent of trust, enforcement mechanisms, and agency
relations. Three of the papers attend to these aspects. / AFRIKAANSE OPSOMMING: Die proefskrif bevat 'n toepassing van institusionele ekonomie op kontemporere
ekonomiese- en ontwikkelingskwessies in Suid Afrika. Die nuwe institusionele
ekonomie het veel te hied tot ekonomiese ontwikkelingsinisiatiewe vera! in
agribesigheid. Institusies word beskou as essentieel tot die funksionering van die
ekonomie, markte en organisasies, ongeag, die nalaat daarvan in die neoklassieke
ekonomie. Die studie poog om te bewys dat 'institusies geld', vera! wanneer sosiale
en ekonomiese transformasie noodsaaklik is.
Die teoretiese basis wat gevestig is in die proefskrif, vind toepassing op ekonomiese
ontwikkelingsuitdagings wat insluit kontraktering, organisatoriese innovasie,
ekonomiese bemagtiging, grondhervorming, bou van sosiale kapitaal, organisatoriese
ontwerp, waardeketting bestuur, entrepreneurskap ontwikkeling, en modes vir
konstruktiewe omgang.
Die studie begin met teoretiese 'n ondersoek in die meer populere nuwe institusionele
ekonomiese literatuur, en spesifiek transaksie koste ekonomie. Dit lei later tot 'n
onverwagse waardering vir die insigting wat die ou institusionele ekonomie genereer,
wanneer die aard van institusies bestudeer word. Gevolglik, verkry die ou
institusionele ekonomie prominensie in die latere deel van die studie, in teenstelling
met die landbou ekonomiese benaderings wat deesdae bespeur word. Die erkenning
aan sosiale kapitaal en institusionele ingeworteldheid is in tred Williamson se
voorgestelde raamwerk vir die ekonomie van institusies is word gebruik as die
konseptuele raamwerk in die tesis.
Waar die nuwe institusionele ekonomie nuttig is in die werwing van kennis, is die ou
institusionele ekonomie nuttig in die kweek van insig en verstaan van probleme en
kompleksiteit. Die proefskrifword op twee maniere hierdeur beinvloed. Eerstens, leun
die latere deel van die werk meer na die ou institusionele ekonomie en die rol van
sosiale kapitaal in die vorming van institusies en ekonomiese gedrag. Tweedens,
verskaf dit 'n fokus op die teoriee oor die aard van die firma wat komplimenter staan
tot transaksie koste ekonomie. Die transaksie koste benadering word aangewend in die ontleding van vertikale integrasie tussen firmas en die relevante ex ante insentiewe
en ex post strukture, waar dit vera! nuttig is.
Meeste studies erken die invloed van institusies op ekomiese uitkomste en gebruik
hoofsaaklik die nuwe institusionele ekonomie en transaksie koste ekonomie. Hierdie
vooroordeel ten opsigte van transaksie koste ekonomie, vind byval as gevolg van die
vermoe om strukturele en organisatoriese uitkomstes te voorspel soos die
doeltreffendheidsdrumpel van firmas, interne orgasnisasie, kontrakte, insentiewe, ens.
Metodologies, moedig dit empiriese en wiskundige benaderings tot ontleding aan, wat
ongelukkig a! die doe! geword het in vele ekonomiese ondersoeke. Drie van die
referate wat in die proefskrif vervat word, behels die identifisering van toepaslike
organisatoriese ontwerpe wat geskoei is op die transaksie kostes wat geldentifieer is.
Die studie bevestig dat sekere aspekte van belang is in institusionele ondersoeke, vera!
in 'n ekonomiese ontwikkelingskonteks soos Suid Afrika. Historiese konteks, word
erken as a kritieke faktor in institusionele ontledings, in die sin dat institusies
onontbeerlik deur geskiedkundige kragte gevorm word. Sosiale kapitaal word ook
erken as 'n belangrike komponent in institusionele ekonomiese ontledings, vera! in
omstandighede waar sosiale kapitaal verweer het as gevolg van polities ekonomiese
manipulasies. Dit veries dat aandag geskenk work aan, ( onder and ere) sosiale konteks,
gelmpliseerde koers afhanklikheid, vertoue, afdwingbare meganismes, en agentskap
verhoudings. Drie van die referate word hieraan gewy.
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An analysis of the financial reporting compliance of South African public agricultural companies15 July 2015 (has links)
M.Com. (International Accounting) / This minor dissertation assesses the extent to which South African public companies that are engaged in agricultural activities are complying with the recognition, measurement and disclosure requirements of IAS 41, Agriculture, as well as whether they are providing any additional voluntary disclosures about their biological assets. Sixteen large South African public companies with material holdings of biological assets in their statements of financial position were selected for analysis. The study used the last published annual financial statements for reporting periods beginning before 1 January 2013 in order to assess compliance with IAS 41 prior to the implementation of IFRS 13. The financial statements of these companies were analysed to identify the existence of both the compulsory disclosures listed in IAS 41, as well as the extent of any voluntary disclosures relating to their biological assets. The results of the analysis show that the majority of South African agricultural companies are using fair value to measure their biological assets at initial recognition as well as at the end of each reporting period. None of the companies, however, is using the quoted price in an active market as the fair value for these assets, implying that companies need to incur additional costs to obtain fair valuations which comply with the requirements of IAS 41. While companies also state that they are using fair value to value their agricultural produce, none of them is providing any further information on how the fair values for their agricultural produce ar e calculated. Most of these companies are complying with the compulsory disclosure requirements of IAS 41, and are also providing certain of the recommended disclosures listed in IAS 41. In total, companies with material holdings of plants as biological assets are complying more fully with the compulsory disclosure requirements of IAS 41 than those with livestock. These companies are also providing more detailed voluntary disclosures about their biological asset holdings than the companies with material holdings of livestock as biological assets. The study concludes that the measurement methods used by companies to value their biological assets and the nature and extent of both compulsory and voluntary disclosures of these assets are sector-specific. This is consistent with the findings of previous research. This study contributes to the existing literature by providing a baseline on the financial reporting of agricultural entities in South Africa prior to the implementation of IFRS 13.
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Genome analysis of an entomopathogenic nematode belonging to the genus Oscheius and its insect pathogenic bacterial endosymbiontLephoto, Tiisetso Elizabeth 10 May 2016 (has links)
A thesis submitted to the Faculty of Science under the school of Molecular and Cell Biology in
fulfilment for requirements for Doctor of Philosophy Degree.
February 2016 / The use of synthetic chemical pesticides has several negative implications for the Agricultural
industry, which include the development of resistance to the insecticides, crop contamination and
the killing of non-target insects. This has brought many scientists in the field of nematology and
entomology to investigate biological control agents which can help solve identified challenges and
these biocontrol agents have also included entomopathogenic nematodes. The majority of
entomopathogenic nematodes species that have been isolated belong to Heterorhabditids and
Steinernematids which act as vectors for insect pathogenic bacteria species belonging to the genera,
Photorhabdus and Xenorhabdus, respectively. However, other species of nematodes, one of which
includes a strain of Caenorhabditis briggsae, have also been shown to act as a vector for an insect
pathogenic strain of Serratia marcescens. Oscheius sp. TEL-2014 EPNs have been observed to act
as vectors for insect pathogenic bacteria belonging to the genus Serratia. In this study a novel
insect pathogenic Serratia sp. strain TEL was isolated from the gut of infective juveniles belonging
to a species of Oscheius sp. TEL-2014. Next generation sequencing of the bacteria was conducted
by generating genomic DNA paired-end libraries with the Nextera DNA sample preparation kit
(Illumina) and indexed using the Nextera index kit (Illumina). Paired-end (2 × 300 bp) sequencing
was performed on a MiSeq Illumina using the MiSeq reagent kit v3 at the Agricultural Research
Council Biotechnology Platform. Quality control and adapter trimming was performed and the
genome was assembled using SPADES. 19 contigs were generated with an average length of
301767 bp and N50 of 200,110 bp. The genome of the Serratia sp. TEL was found to be 5,000,541
bp in size, with a G+C content of 59.1%, which was similar to that of other Serratia species
previously identified. Furthermore, the contigs were annotated using NCBI Prokaryotic Genome
Automatic Annotation Pipeline. Features of the annotated genome included protein encoding
sequence or genes, rRNA encoding genes, tRNA encoding genes, ncRNA sequences and repeat
regions. 4,647 genes were found and 4,495 were protein-coding sequences (CDS). The genome
contains 36 pseudo genes, 2 CRISPR arrays, 13 rRNA genes with five operons (5S, 16S, 23S), 88
tRNAs genes, 15 ncRNA sequences and 9 frameshifted genes. Several genes involved in virulence,
disease, defense, stress response, cell division, motility and chemotaxis were identified. This
genome sequence will allow for the investigation of identified genes and that will be critical in
furthering the understanding of the insect pathogenicity of Serratia sp. strain TEL. Furthermore, it
will provide additional genomic insights about the insect-nematode interactions and thus help us
improve their ability to be used as biological control agents in agricultural industries. Oscheius sp.
TEL-2014 was tested for its entomopathogenicity and it was found that this species was able to
infect and kill two model insects Galleria mellonella and Tenebrio molitor. This new nematode
species brought 100% mortality within 72 h post-exposure in G. mellonella and whereas, within 96
hours in T. molitor. Following morphometrics analysis of Oscheius sp. TEL-2014 it was concluded
that this nematode is described as a novel entomopathogenic nematode species based on its
morphometrics and 18S rRNA gene sequence originality. Whole genome sequencing of Oscheius
sp. TEL-2014 inbred lines (7 and 13) was performed using Illumina Hiseq sequencing system and
paired ends library preparation protocol. Sequencing reads assembled on Velvet resulted in
generation of 75965 contigs (line 7) and 53190 contigs (line 13). Gene prediction tools showed that
proteins involved in gene expression and DNA replication are present in Oscheius sp. TEL-2014.
The draft genome of Oscheius nematodes will support the improvement and initiation of further
studies intended to help us understand the molecular and metabolic processes in this genus.
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A expansão não conflituosa entre a produção de etanol e a produção de alimentos no Brasil /Pinto, Giovani Ângelo Soares. January 2015 (has links)
Orientador: Sebastião Neto Ribeiro Guedes / Banca: Alexandre Sartoris Neto / Banca: Carlos Eduardo de Freitas Vian / Resumo: O possível impacto negativo causado pela produção de biocombustíveis sobre a segurança alimentar sempre foi objeto de estudo nos meios acadêmicos desde a década de 1970, quando o preço internacional do petróleo se elevou consideravelmente. Em se tratando do Brasil, há evidências que esse tipo de problema não ocorre de modo significativo nos tempos atuais. Diante desse fato, surge o objetivo principal deste estudo: verificar se a ausência de competição no Brasil entre a produção de etanol e a produção de alimentos ocorre devido ao aumento de eficiência produtiva no setor agropecuário ou se dá pela expansão da produção de cana-de-açúcar e de alimentos em áreas onde ocorre desmatamento da vegetação nativa. Para alcançar tal objetivo, o presente trabalho contará com uma metodologia baseada no conceito de elasticidade, na qual os valores médios de variáveis referentes ao cultivo de determinadas commodities alimentares serão comparados com os respectivos resultados referentes ao cultivo de cana-de-açúcar / Abstract: The possible negative impact of biofuel production on food security has always been an object of study in academic circles since the 1970s, when the international price of oil has risen considerably. In the case of Brazil, there is evidence that this type of problem does not occur significantly in recent times. Given this fact, the aim of this study arises: verify that the lack of competition in Brazil between ethanol production and food production occurs due to increased production efficiency in the agricultural sector or is by expanding production of sugarcane and food in areas where there is deforestation of native vegetation. To achieve this goal, this paper will include a methodology based on the concept of elasticity, in which the average values of variables related to the production of certain food commodities will be compared with the corresponding results related to the production of sugarcane / Mestre
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