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The Effects of Roasting Time and Temperature on the Antioxidant Capacity of Cocoa Beans from Dominican Republic, Ecuador, Haiti, Indonesia, and Ivory CoastHarrington, Whitney Leigh 01 August 2011 (has links)
Roasting is an important processing step for developing cocoa flavor, color, and aroma. Cocoa beans contain polyphenolic compounds, which can be desirable antioxidants. Oxygen Radical Absorbance Capacity (ORAC) values can be used as an indicator of health benefits of antioxidants in foods. ORAC values measure total antioxidant capacity of different foods by measuring antioxidant scavenging activity against peroxyl radical induced by 2,2’-azobis (2-amidinopropane) dihydrochloride (AAPH). This measurement of total antioxidant capacity gives a complete assessment during which the inhibition time and inhibition degree are measured as the reaction comes to a completion. ORAC values were determined as Trolox Equivalents (TE). Cocoa beans were also measured for antioxidants using Total Phenolics assay and DPPH assay and measured as gallic acid equivalents (GAE). Cocoa beans from the Ivory Coast were roasted at varying times (10-40 minutes) and temperatures (100ºC -190ºC). It was determined that cocoa beans from the Ivory Coast, roasted at 130ºC for 30 minutes resulted in an ORAC value of 522,789 μmol (micromoles) TE/g, GAE value of 2.46 mg/L as determined by Total Phenolics, and GAE value of 1.48 mg/L as determined by DPPH assay. The analyzed values tended to decrease at the highest temperatures and times of roasting. Cocoa beans from different countries were roasted at 130ºC for 30 minutes and antioxidants were analyzed. It was determined that Dominican Republic and Ecuador had the highest TE values (487,913 and 463958 μmol (micromoles) TE/g respectively). GAE differed and Total Phenolic assay found Haiti had the highest GAE (3.26 mg/L) and DPPH assay found Ivory Coast and Dominican Republic had the highest (0.623 and 0.610 mg/L respectively). If an acceptable flavor, color, and aroma of cocoa can be developed at a roasting temperature closer to 130ºC than to 160ºC, then a greater antioxidant content should occur in dry cocoa powder.
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På vems villkor? : En fallstudie om barnarbete i Ghana / On who’s conditions : A case study of child labor in GhanaAxell, Sandra, Mugororoka, Chanelle Fortune January 2010 (has links)
The purpose of this paper is to describe and analyze two factors contributing to child labor in Ghana, one of the world's largest producers of cocoa. These two factors are: poor countries economic and political dependency on the rich countries, political leader’s ambitions and decisions. We will also describe and analyze the UN's efforts and measures to combat child labor. The method we used was a case study of child labor in Ghana‘s cocoa industry together with interviews. Questions to be answered were: How is poor countries economic and political dependency towards rich countries a contributing factor to child labor? How do political leader’s ambitions and decisions affect child labor? Despite UN efforts to combat child labor it does not diminish in some parts of the world such as West-Africa, why? The theories used were the Dependency Theory and Political Leadership Theory. Our results show that dependency theory can contribute to child labor. It does that because of colonialisms effects still are showing in poorer countries. This in turn leads to that children need to work to help their family economically. UN broad actions and measures to combat child labor did not help to reduce child labor. UN must specify its policies and actions in each country depending on what kind of child labor it is. Political leadership was important to ensure that child labor should decrease. The political leader should have understood the issue and ensured the protection of children under 15 from hazardous work, this by ensuring that there were laws that protected them, but also by accepting the United Nations Convention of the Rights of the Child (UNCRC).
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Recombinant expression of plant diacylglycerol acyltransferases from tissues that accumulate saturated fatty acidsZhang, Ying Unknown Date
No description available.
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Agronomic, physiological and genetic studies on a dwarf mutant of cocoa (Theobroma cacao L.)Eremas Tade Unknown Date (has links)
Cocoa (Theobroma cacao L.) is an important cash crop in the coastal areas of Papua New Guinea (PNG). In 2000, a mutant cocoa genotype MJ 12-226, with abnormal growth characteristics was identified at the Cocoa and Coconut Institute of PNG. The mutant, found among progenies of the cross Scavina 12 x Nanay 149, was characterized by dwarfing, small and narrow leaves, a small root system and strong branching habit. This study was designed to improve the understanding of the dwarf cocoa mutant and identify its relevance to future cocoa farming. The specific objectives are to investigate the feasibility of using a dwarf mutant of cocoa as a commercial rootstock for various hybrid cocoa clones, to study the genetics of this dwarf mutant and the role of plant hormones in differentiating this mutant from the normal phenotype. This study was carried out at the Cocoa and Coconut Institute of PNG, Rabaul, Papua New Guinea, and at the University of Queensland, Gatton Campus, Australia. The comparative study of mutant and normal cocoa seedlings revealed distinct vegetative differences between the two genotypes at the nursery stage. The largest effects of the mutant genotype are on stem elongation, short internodes, multiple stems, root growth and leaf growth. The agronomic results indicated that the mutant rootstock significantly reduced tree vigour at least in the early years. When used as a rootstock, the mutant had a significant dwarfing effect on scion growth of cocoa clones in the nursery and persisted in the field 12 months after planting. After that, the cocoa clones grafted on mutant rootstock reverted to normal growth. It was postulated that the accumulation of endogenous growth substances and cambial activity between the scion (normal) and the rootstock overcame the dwarfing effect of the mutant genotype. Yield and vegetative data collection from this trial ceased on May 2006 and recommenced in May 2007 to allow trees to recover from heavy canopy pruning due to cocoa pod borer attack. This resulted in one year loss of yield and vegetative data from this experiment. The first two years’ yield data indicated no significant differences between mutant, normal segregants and commercial rootstocks. However, cocoa clones bud grafted on these mutant rootstocks produced significantly greater yield at higher planting density compared with lower densities and this was sustained for two years. However, it might be expected that competition among cocoa trees would increase with increased size of trees, favouring low density planting and reducing the differential performance of the trees under high density planting with time. The major advantages of reducing tree vigour are to improve the harvest index, ease of harvesting, pruning and overall management of the trees. The continuation of this study to collect mature tree yield data (from fifth to eighth years) would confirm these results. This work has also demonstrated for the first time that cocoa clones grafted on mutant rootstock can produce similar yields to clones grafted on normal or commercial rootstocks. Moreover, this study has also established that cocoa clones derived from orthotropic scions can yield the same as plagiotropic scions when grafted on to either mutant or normal rootstocks. Therefore, it is proposed that mutant rootstocks and orthtropic scions should also be considered for future use in cocoa farming. The strong branching habit and dwarfing stature of the mutant suggested that the mutation affects the quantity or the balance of plant growth hormones, or both. The effect of exogenously applied gibberellic acid (GA3) on developmental processes in dwarf mutant and normal cocoa seedlings was studied. Both dwarf mutant and normal one month old cocoa seedlings responded to gibberellic acid (GA3) by accelerated longitudinal growth, especially seedling height. Paclobutrazol (PBZ) applied to normal cocoa seedlings altered the growth so that they almost resembled the mutant phenotype. It was postulated that PBZ prevented GA biosynthesis in the normal cocoa seedlings and therefore decreased bioactive auxin (IAA) which, in turn, then promoted lateral shoot growth; PBZ also slightly retarded plant growth. Synthetic auxin (IBA/NAA) significantly inhibited lateral bud sprouting and growth of intact, decapitated and nodal segments of mutant and normal cocoa seedlings compared with control and those treated with IAA. It appears that the mutant and normal cocoa genotypes have a similar capacity to metabolize IAA and this capacity was much greater than for synthetic auxins. The results suggested that auxin levels in the mutant seedlings were probably limiting, and therefore affected biosynthesis of gibberellic acid thus resulting in the dwarfing characteristics of the mutant cocoa genotype. However, analysis of endogenous IAA and GA1 levels at four months old did not reveal differences between the mutant and normal seedlings. The present genetic studies which included backcrossing, test crossing and selfing of F1 progenies confirmed earlier work on the mutant and showed that the mutant was probably heterozygous (Dd). The allele (DD) in mutant cocoa is probably lethal in nature because the phenotype of the homozygote was not observed amongst the mutant progenies. Mutant segregants were obtained in a 1:1 ratio only when the mutant clone was used as the female; however, when the mutant was used as male, very few mutant segregants were obtained. This suggested selective pollen viability (pollen grains carrying the D allele are nonviable) or an incompatible reaction between pollen tubes (D carrying pollen) and style or ovule. The selfing and test-crosses of F1 progenies resulted in deviation from the expected 3:1 segregation ratio to a 1:1 ratio.
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A study of the starch of cocoa beans and chocolate productsSchmieder, Robert Leonard. January 1900 (has links) (PDF)
Thesis (M. S.)--Pennsylvania State University, 1976. / Includes bibliographical references.
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Estado de Santa Cruz: o separatismo no mosaico baiano, (1930-1980)Neves, Maricélia Cardoso Matos January 2006 (has links)
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Previous issue date: 2006 / O objetivo específico desta pesquisa foi analisar historicamente as manifestações separatistas ocorridas dentro da sociedade cacaueira da Bahia, entre 1930 e 1980, bem como, investigar quais as origens desse sentimento separatista. Buscou - se perceber em que momento e de que forma as lideranças da região cacaueira passaram a elaborar um projeto de desmembramento do Estado da Bahia, concretizado no projeto de criação do Estado de Santa Cruz. Coube perceber, também, a gama de interesses dos grupos políticos adeptos ou não do ideal separatista, bem como, as relações políticas e econômicas que essa região manteve com o Governo do Estado da Bahia. / Salvador
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Seleção de leveduras pectinolíticas para melhoria da fermentação do cacau / Selection of pectinolytic yeast to improve the cocoa fermentationMarcos Pinto Monteiro de Oliveira 10 April 2015 (has links)
As principais matérias-primas do chocolate, obtidas a partir das sementes secas do fruto do cacaueiro (Theobroma cacao), são a manteiga e o líquor de cacau. Para se obter matérias-primas de alta qualidade é necessário que o processo que antecede a industrialização, no caso a fermentação, seja padronizado para que sejam formados nas sementes os precursores de aroma, sabor e cor característica do chocolate. No interior do fruto do cacaueiro são encontradas as sementes envoltas por uma mucilagem composta por: água, pectina, sacarose, glicose, frutose, proteínas, ácidos e sais. O processo fermentativo do cacau ocorre sem qualquer tipo de inóculo ou padronização. Devido a este fato, os padrões de qualidade das sementes obtidas são as mais adversas e muitas vezes a presença de compostos interferentes e não desejáveis são formados ao longo desse caminho. Visando a otimização do processo fermentativo este trabalho teve por objetivo selecionar leveduras de ocorrência espontânea presentes na fermentação do cacau, reinoculá-las no processo natural in locu e comparar com o processo de ocorrência espontânea, avaliando assim o potencial do coquetel de leveduras a ser utilizado futuramente para padronizar o processo. Para tanto, foram isoladas 367 linhagens de leveduras de ocorrência espontânea em duas fazendas no sul da Bahia. As linhagens passaram por uma seleção onde foi implementado um programa de seleção composto por três ensaios: ensaio de crescimento em pectina; análise de Açúcar Redutor Total livre (ART); e avaliação de atividade enzimática. Foi possível selecionar três linhagens de leveduras promissoras com potencial pectinolítico as quais foram testadas in locu no município de Itabuna-BA. O processo de isolamento, seleção e reintrodução das linhagens selecionadas no processo fermentativo do cacau se mostrou uma prática altamente eficaz. Os resultados obtidos com a inoculação inicial de leveduras selecionadas, antecipou os eventos como produção de etanol, ácido acético, drenagem do mel e elevação da temperatura em 24 horas em relação ao controle. / The fundamental raw material to produce chocolate, obtained from dried seeds of cocoa fruit (Theobroma cacao), are butter and cocoa liquor. In order to obtain high quality of raw materials, it is necessary standardize the procedure before industrialization, known as fermentation, so that the aroma, taste and color precursors of chocolate must be formed in the seeds. Inside the fruits exists a white mucilaginous pulp, which covers the beans, it contains water, pectin, sucrose, glucose, fructose, proteins, acids and salts. The fermentation of cocoa seeds occurs in wooden boxes or piles on the ground without any control or standardization. Due to this fact, the quality of the seeds are the most adverse, the presence are often of interfering compounds and undesirable products could be formed along the way. To optimize the fermentation process this study aimed to select pectinolytic yeasts of spontaneous occurrence from cocoa fermentation, re-inoculate them in the natural process and compare with the spontaneously occurring process. Consequently evaluate the yeast cocktail potential as a standard inoculum. Therefore, we isolated 367 yeast strains from spontaneous cocoa fermentation in two different farms in southern Bahia - Brazil. The strains were analyze to a selection-screening program, which consists of three tests: ability to grow in pectin medium; Total free Reducing Sugar Analysis (ARTL); and evaluation of enzyme activity. It was possible to select three yeast strains with promising pectinolitic potential. Those strains were tested in locu in Itabuna-BA, Brazil. The results of that program, selection and re-introduction in the fermentation process proved to be a highly effective practice. The results obtained with the initial inoculation of selected yeasts, could anticipate the fermentation events in 24 hours, such as the production of ethanol, acetic acid, sweating drainage and temperature rise when compared with the control.
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Análise geoambiental da região da Costa do Cacau - Bahia / Geoenvironmental analysis of the Coast Region Cocoa - BahiaSantos, Maria Crizalda Ferreira, 1955- 21 August 2018 (has links)
Orientador: Regina Célia de Oliveira / Acompanhado de mapa (folha solta), acondicionado em envelope / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-21T11:58:32Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: Este trabalho propõe um Zoneamento Ambiental da Região Costa do Cacau, Bahia e busca aplicar e desenvolver uma pratica dos elementos conceituais, teóricos e metodológicos da Teoria Geossistêmica, que enfatiza a integração dos componentes do meio natural, sua integração com seus elementos, conexões e processos. O potencial dos recursos naturais utilizados pelo homem é caracterizado como um sistema de recursos naturais aos quais se integram sociedades e num binômio inseparável Sociedade-Natureza. Buscamos através da analise geoambiental articular a relação entre os geossistemas, sua transformação, as dimensões e os processos de alteração da paisagem para diagnosticar o estado de degradação e os estados ambientais que se encontram os geossistemas. Partindo do principio de que os geossistemas, no seu processo de ocupação, visam à formação de unidades socioambientais, esta tese visa analisar as transformações ambientais e estabelecer comparações do Estado ambiental e grau de degradação, além de delimitar e analisar os geossistemas e os sistemas antrópicos da Região Costa do Cacau, Bahia. Para controle ou mitigação dos prejuízos ambientais identificados nos geossistemas naturais e o Estado Ambiental em que se encontram cada unidade geoecológica, além do uso e ocupação, incluindo a interpretação dos impactos sobre o processo de ocupação e seus agentes de alteração e redução da biodiversidade. A partir dos geossistemas como unidades naturais integrais, foi possível distinguir suas modificações e transformações da natureza feitas pela sociedade, à diversidade de tipos de ocupação que determinaram as suas condições naturais e a produção social / Abstract: This paper proposes an environmental zoning of the Costa do Cacau Bahia region and aims to apply and develop a practice of conceptual, theoretical and methodological elements of the Geosistemica Theory that emphasizes the natural environment components integration, its integration with its elements, connections and processes. The potential of natural resources used by man is characterized as a natural resources system to which societies integrate and in an inseparable binomial society-nature. We aim, through geoenvironmental analysis articulate the relationship among geosystems, their transformation, the dimensions and processes altering the landscape, to diagnose the degradation status and the geosystems environmental status. Considering the premisses that the geosystems, in their occupation process, aim the formation of socioenvironmental units, this thesis analyses the environmental transformations and compares the environmental state and amount of degradation, and limits and analyzes the geosystems and anthropic systems of the Costa do Cacau, Bahia region. For control or mitigation of the environmental prejudices identified in the natural geosystems and the environmental state of each geoechological unit, and the use and occupation, including the interpretation of the impacts on the occupation process and biodiversity reduction and alteration agents. From geosystems as integral natural units, it was possible to distinguish its modifications and nature transformations done by society, the diversity of occupation types that determined the natural conditions and social production / Doutorado / Análise Ambiental e Dinâmica Territorial / Doutora em Geografia
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Left Behind: A Farmer’s Fate in the Age of Sustainable DevelopmentMelo, Cristian J. 08 November 2010 (has links)
Globalization is eroding the livelihoods of small farmers, a significant and vulnerable class, particularly in the developing world. The cost-price squeeze stemming from trade liberalization places farmers in a race to the bottom that leads to displacement, poverty, and environmental degradation. Scholars and activists have proposed that alternative trade initiatives offer a unique opportunity to reverse this trend by harnessing the power of the markets to reward producers of goods with embedded superior cultural, environmental, and social values. Alternative trade via certification schemes have become a de facto prescription for any location where there is a need to conciliate economic interest with conservation imperatives. Partnerships among commodity production farmers, elite manufacturers and wealthy northern consumers/activists do not necessarily have win-win outcomes. Paradoxically, the partnerships of farmers with external agencies have unexpected results. These partnerships develop into dependent relationships that become unsustainable in the absence of further transfers of capital. The institutions born of these partnerships are fragile. When these fledging institutions fail, farmers are left in the same situation that they were before the partnership, with only minor improvements to show after spending considerable amounts of social and financial capital. I hypothesize that these failures are born out of a belief in a universal understanding of sustainability. A discursive emphasis on consensus, equity and mutual benefit hides the fact that what for consumers it is a matter of choice, for producers is a matter of survival. The growth in consumers’ demand for certified products creates a race for farmers to meet these standards. My findings suggest that this race generates economically perverse effects. First, producers enter into a certification treadmill. Second, the local need for economic sustainability is ignored. Third, commodity based alternative trade schemes increase the exposure of communities to global shocks. I conclude by calling for a careful reassessment of sustainable development projects that promote certification schemes. The designers and implementers of these programs must include farmers’ agenda in the planning of these programs.
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Estudo da extração e caracterização bioquímica das esterases de soja (Glycine max L.) e sorgo (Sorghum bicolor L.) / Extraction and biochemical characterization study of esterases from soybean (Glycine max L.), sorghum (Sorghum bicolor L.) seedBarros, Márcio de 18 August 2018 (has links)
Orientador: Gabriela Alves Macedo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-18T14:07:21Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: As esterases (carboxil-ester hidrolases; EC 3.1.1.3) e as lípases (triacilglicerol acilhidrolases; EC 3.1.1.3), são, coletivamente, conhecidas como enzimas lipolíticas, por apresentarem habilidade para hidrolisar ésteres de ácido carboxílico de cadeia curta e longa, respectivamente. As lipases catalisam a hidrólise de ligações éster na interface orgânica-aquosa, diferentemente das esterases que catalisam a hidrólise de ligações éster de substratos em meio aquoso. O objetivo deste trabalho foi avaliar a atividade de esterase nos extratos brutos das sementes de soja (Glycine Max L.), sorgo (Sorghum bicolor L.) e cacau (Theobroma cacao); selecionar as sementes que apresentam maior atividade esterásica, e avaliar as características bioquímicas das enzimas brutas e purificadas. Foi observada atividade lipolítica e esterásica nas amêndoas de cacau e esterásica nas sementes de soja e sorgo. Foram avaliadas diferentes soluções para a extração da esterase de soja e observou-se que a solução de CaCl2 0,01M mostrou-se mais eficiente na extração da enzima sendo obtido atividade igual a 1,83 U.mg-1. No estudo da concentração da esterase de sorgo por fracionamento com sulfato de amônio foi obtido maior atividade (188,30 U.mg-1) utilizando 60% de saturação do sal. Na precipitação da esterase de soja com sulfato de amônio a enzima apresentou baixa estabilidade. Em relação aos parâmetros bioquímicos, a esterase de sorgo apresentou atividade ótima na temperatura de 40ºC, porém apresentou baixa estabilidade nesta temperatura, o pH ótimo de atividade da enzima foi pH 8 e a enzima demonstrou ser estável em toda faixa de pH estudada (3 a 10), quanto ao substrato a enzima demonstrou maior afinidade por pNPB cuja atividade foi 70,82 U.mL-1. Quanto a esterase de soja, as preparações bruta e purificada apresentaram o mesmo comportamento apresentando atividade ótima em pH 8,0 e a 40°C, estabilidade na faixa de pH 6,5 a 10 e estabilidade até 50°C durante 60 minutos. O composto polietilenoglicol de peso molecular 0,4; 6 e 10kDa ativou respectivamente 140, 170 e 140% a esterase de soja bruta. A esterase de soja purificada apresentou um aumento de 11 vezes na atividade, com um Km de 0,85 µM e Vmax 31,5 U.mL-1. As características apresentadas pelas esterases de soja e sorgo as qualificam para aplicação industrial / Abstract: Esterases (carboxyl ester hydrolases; EC 3.1.1.3) and lipases (glycerol ester hydrolases EC 3.1.1.3) are enzymes capable of hydrolyzing short and longchain carboxylic acid esters, respectively. The lipases hydrolyze the ester bonds of their water-insoluble substrates at the organic-aqueous interface, differently from the esterases, that hydrolyze the ester bonds of their soluble substrates in the aqueous medium. The objective of this work was to evaluate the presence of esterases and/or lipases in crude extracts of soybean (Glycine Max L.), sorghum (Sorghum bicolor L.) and cacao (Theobroma cacao) seeds, select the seeds with the highest esterase activities, and study the biochemical properties of the crude and purified enzymes. Lipolytic and esterase activities were found in the cacao seeds, but only esterase activity in the soybean and sorghum seed crude extracts. Different solutions were evaluated to extract the soybean esterase, and it was found that 0.01M CaCl2 was the most efficient, obtaining activity of 1.83 U.mg-1. In the fractional precipitation process with ammonium sulfate aimed at concentrating the sorghum esterase, the highest activity (188.30 U.mg-1) was obtained with 60% saturation of the salt. However, when ammonium sulfate was used to concentrate the soybean esterase, low enzyme stability was observed. With respect to the biochemical parameters, the sorghum esterase showed optimum activity at pH 8 and a temperature of 40°C, but showed low stability at 40°C although it was stable in the entire pH range studied (3 to 10). With respect to the substrates, it showed greatest affinity for short-chain fatty acids (pNPB), with activity of 70.82 U.mL-1. The crude and purified preparations of the soybean esterase showed the same behavior, with optimum activity at pH 8 and 40°C, and were stable at pH values between 6.5 and 10 and at temperatures up to 50ºC for 60 minutes Polyethylene glycol with molecular weights of 0.4, 6 and 10kda activated 140, 170 and 140% of the enzyme activity, respectively. The soybean esterase was purified using DEAESepharose ion exchange column chromatography followed by passage through a Sephadex G-100 gel column and ultra-filtration, leading to an overall purification of 17.6 fold, with a Km of 0.85 µM and Vmax of 31.5 U.mL-1. The biochemical characteristics presented by the soybean and sorghum seed esterases qualified them for industrial applications / Doutorado / Ciência de Alimentos / Doutor em Ciência de Alimentos
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