Thèses sur le sujet « Coffee bean »

The coffee industry relies on fundamental research to improve the techniques and processes related to its products. However, the exploitation of mathematical models that provide insight into improving the roasting of coffee beans has been largely unexplored. In this thesis, we develop mathematical models to understand specific processes in a roasting coffee bean that are crucial in flavour development and consistency. We explore these processes using several models in a multiphase framework to highlight how phase changes, gas pressures, and various chemical reactions occur in different parts of the bean. These new models are then compared to new and existing experimental data, where the merits and pitfalls of each model are then discussed. One main phenomenon that is crucial to the roasting process is the evaporation of water. Various models of evaporation rates are proposed and incorporated into the multiphase models, where the resulting qualitative features of the behaviour are discussed. The behaviour of these multiphase models is studied using asymptotic analysis and the leading-order water and vapour transport predicted from this analysis faithfully reproduce the salient features of the model. We also examine how deformations and material stresses occur during the roasting process. We model the cellulose structure of a coffee bean as a poroviscoelastic material and couple the resulting constitutive equations with aforementioned multiphase models. The qualitative behaviour of this coupled model is discussed for various parameter regimes and used to explain various physical phenomena observed during the roasting process. A summary of key findings is then presented.

L'objectif de cette thèse est de contribuer à déterminer les régions possibles de croissance Aspergillus Ochraceus (O.A.) lors du séchage du café. Il est admis que ce champignon qui produit une toxine (Ochratoxine A), se développe pour une activité de l'eau supérieure à 0,8. La structure interne du grain de café est étudiée par microscopie, stéréoscopie et RMN. Ces observations mettent en évidence une grande hétérogénéité de structure à l'échelle du grain et à l'échelle cellulaire. Les isothermes de désorption pour cinq parties du grain sont établies. Mis à part la parche qui présente une structure ligneuse, il n'a pas été mis en évidence de différences notables des isothermes dans les autres parties du grain. L'étude des transferts d'eau est focalisée à la surface du grain, site privilégié de la croissance d'O.A. où trois structures présentent une résistance au transfert d'eau : l'endosperme, la couche argentée, la parche. Dans l'endosperme, le transport est décrit par une loi de diffusion. Pour des teneurs en eau supérieures à 65%, un coefficient de diffusion constant décrit bien la cinétique d'un grain entier. Au dessous de cette teneur en eau, le coefficient de diffusion décroit avec la teneur en eau. Ceci est dû, d'une part, à la réduction de l'espace poral occupé par l'eau et, d'autre part, à l'augmentation de la liaison entre l'eau et le squelette solide lorsque la teneur en eau diminue. Les essais de diffusion avec et sans la couche argentée montrent que la contribution de cette dernière est de l'ordre de 10%. Le flux d'eau dans la parche est supposé proportionnel à la différence d'activité de part et d'autre de celle-ci. Une technique expérimentale originale est proposée pour mesurer la résistance au transfert d'eau de la parche. Les résultats expérimentaux sont utilisés dans un modèle simple décrivant la cinétique et le profil d'activité de l'eau à la surface du grain. En fonction des conditions de séchage imposées, il devrait permettre de juger si l'environnement à la surface du grain est favorable ou non à la contamination du café.

Coffee production in Costa Rica has brought prosperity to many small farmers, but conflicts of interest with the companies which process and market coffee are still a problem. In addition, producers and processors are plagued by the periodic market cycles of agricultural commodities. Various agencies have promoted cooperatives to help small farmers deal with these problems, but they often fail due to poor management and lack of participation.
This thesis, a multi-layered study of coffee production, processing, and marketing, examines how household producers manage the constraints and opportunities posed by the international market, the Costa Rican state, and the coffee tree itself. A comparative analysis between cooperative and private coffee processors; between two rural communities; and among households in these communities provides the ethnographic context in which the effectiveness of cooperatives as mediating institutions between producers and the world market is analyzed.

The analysis of urinary metabolite changes can provide information on the effects of food supplements or health-promoting products on healthy subjects or animal models. Specimen collection is non-invasive, long-term experiments can be easily conducted and urinary biomarkers of oxidative stress can also be measured, offering the opportunity to study the effects of a nutritional intervention and evaluate the redox status of the considered organism. In this thesis, three natural extracts were selected, namely Polygonum cuspidatum Sieb. et Zucc. (rich in resveratrol), Vaccinium macrocarpon Aiton (cranberry, rich in type A procyanidins) and green Coffea canephora Pierre ex Froehn. beans (GCBE, rich in chlorogenic acids), on the basis of their distribution on the market and on the basis of the information regarding their in vivo activity actually available in literature. In the first part of the work, the effects of P. cuspidatum dry extract were studied in healthy adult rats during a 49-days supplementation, using a combined 1H NMR and UPLC-HRMS metabolomics approach. Because of the reported antioxidant activity of resveratrol, the urinary amounts of two oxidative stress biomarkers were measured by targeted HPLC–MS/MS analyses and, due to the supposed “anti-aging” effects of resveratrol, multivariate models were designed in order to compare the aging effects between control and treated animals. Specific biomarkers were then selected and identified, and their amounts in urine were monitored throughout the experimental period. UPLC-MS metabolomics approaches were used to evaluate the mode of action of cranberry against uropathogenic Escherichia coli in two independent experiments, using an animal model and enrolling healthy adult volunteers, respectively. The experimental design was similar for the two trials, and the aim was to observe if the results obtained from the first animal experiment were reproducible in humans, being cranberry supplements claimed for treatment of UTIs in human consumers. In the first experiment, healthy Sprague−Dawley rats were orally supplemented with a standardized cranberry extract for 35 days, to mimic a prolonged consumption of cranberry by healthy subjects. 24-h urinary outputs were collected weekly during the experiment, and samples were subjected to UPLC−MS analysis using an untargeted approach. In a second experiment on the same animal model, a single dose of cranberry was administered to animals and the changes of urinary composition at 2, 4, 8, and 24 h after extract administration were monitored. Anti-adhesive properties of all the urine samples were studied. Furthermore, the markers related to cranberry intake were discovered using a multivariate data analysis approach. Finally, a specific chromatographic method was developed for the measurement of unmodified PAC-A in urine. In the experiment involving human volunteers, these consumed an oral sachet containing 360 mg of dry cranberry extract and 100 mg of quercetin. Urine samples were collected at 2, 4, 6, 8 ad 24 hours after product administration and the anti-adhesive properties of urine samples were tested using an in vitro assay on E. coli. In order to correlate possible observed bioactivity with modification of urinary composition, LC-MS-based targeted and untargeted metabolomics approaches were used. Finally, a clinical trial on a small number of healthy adult volunteers was performed to study the effects of a prolonged (30 days) supplementation with 400 mg of green coffee bean extract. The 24-h urinary samples were collected weekly, and analyzed by LC-MS. Multivariate data analysis approaches were applied and also targeted analysis were performed to measure urinary oxidative stress biomarkers, namely allantoin and 8-hydroxydeoxyguanosine (8-OHdG), in order to assess the potential antioxidant activity of GCBE in vivo.
L’analisi del metaboloma urinario e delle sue variazioni può fornire utili informazioni sull’effetto del consumo di prodotti nutraceutici da parte di volontari sani o in modelli animali. I vantaggi di usare l’urina come matrice di studio sono correlati alla scarsa invasività di campionamento, al semplice trattamento pre-analitico dei campioni, alla possibilità di progettare e condurre esperimenti a lungo termine ed alla possibilità di quantificare alcuni markers di stress ossidativo. Sulla base della loro attuale diffusione sul mercato e dei dati di bioattività disponibili in letteratura, per il lavoro di tesi qui presentato sono stati presi in esame tre prodotti nutraceutici, contenenti rispettivamente estratti secchi di Polygonum cuspidatum Sieb. et Zucc. (contenente resveratrolo), Vaccinium macrocarpon Aiton (cranberry, contenente proantocianidine di tipo A) e semi verdi di Coffea canephora Pierre ex Froehn. (GCBE, contenente derivati dell’acido clorogenico). Nella prima parte di lavoro sono stati studiati gli effetti del consumo di un estratto secco di Polygonum cuspidatum per 49 giorni in ratti adulti sani, impiegando un approccio metabolomico combinato NMR/UPLC-MS. Per studiare l’effetto “anti-aging” attribuito al resveratrolo, sono stati sviluppati dei modelli multivariati in cui sono stati posti a confronto il gruppo “trattato” ed il gruppo di controllo; da questi sono stati selezionati ed identificati specifici biomarkers di invecchiamento, i quali livelli urinari sono stati poi monitorati per tutto il corso dell’esperimento. Un simile approccio UPLC-MS è stato in seguito impiegato per studiare l’attività ex vivo di un estratto secco di cranberry contro un ceppo di Escherichia coli uropatogenico. In questo caso sono stati disegnati due esperimenti indipendenti, in cui gli effetti del trattamento sono stati studiati rispettivamente in ratti sani ed in volontari umani. Nel primo esperimento è stato somministrato un estratto secco di cranberry standardizzato in procianidine per 35 giorni a ratti Sprague-Dawley, per mimare un consumo prolungato di cranberry da parte di pazienti umani. Settimanalmente è stata effettuata la raccolta delle urine delle 24 ore, ed i campioni raccolti sono stati analizzati mediante un approccio untargeted UPLC-MS. Impiegando lo stesso modello animale, è stata effettuata una singola somministrazione di cranberry e la variazione della composizione urinaria è stata studiata a 2, 4, 8 e 24 ore dopo il trattamento. Gli stessi campioni sono stati utilizzati per testarne le proprietà antiadesive contro Escherichia coli e per determinare i markers urinari correlati all’assunzione di cranberry, grazie all’impiego di tecniche statistiche multivariate ed allo sviluppo di specifici metodi cromatografici atti alla determinazione di PAC-A intatte in matrice urinaria. Nel secondo esperimento, ai volontari umani sani è stato chiesto di consumare un integratore contenente 360 mg di estratto secco di cranberry e 100 mg di quercetina. I campioni urinari sono stati raccolti a 2, 4, 6, 8 e 24 ore a seguito del trattamento e le loro proprietà antiadesive sono state testate contro un ceppo di E. coli uropatogenico. In modo da correlare l’attività biologica osservata in vitro con la modifica composizionale indotta dal trattamento, sono stai impiegati degli approcci LC-MS targeted e untargeted. Infine, è stato condotto uno studio clinico su un piccolo numero di volontari sani per studiare gli effetti di una integrazione con 400 mg di GCBE per 30 giorni. I campioni urinari delle 24 ore sono stati raccolti settimanalmente ed in seguito analizzati mediante LC-MS ed analisi statistica multivariata. Sono state eseguite analisi targeted per quantificare biomarkers urinari di stress ossidativo, al fine di valutare la potenziale attività antiossidante di GCBE in vivo.

A escalada tarifária, isto é, o emprego de tarifas de importação crescentes conforme o grau de processamento de um produto estimula a importação de produtos primários em detrimento dos processados nos mercados importadores que a exercem. O objetivo deste trabalho foi mensurar os ganhos ao Brasil da eliminação da escalada tarifária em produtos do café na UE, e da soja na China e na UE, e comparar com a redução da escalada proposta na Rodada Doha da OMC. Foram simuladas reduções tarifárias e quantificados os impactos comerciais através da modelagem de equilíbrio parcial segundo Laird e Yeats (1986). Pelos resultados, as negociações sob Doha podem reduzir a escalada tarifária incidente sobre os produtos analisados, no entanto, sem a eliminar, o que requereria maiores cortes nas tarifas de importação. Os impactos comerciais, que se mostraram mais expressivos na simulação de eliminação da escalada tarifária do que na de redução sob Doha, indicaram favorecimento das exportações brasileiras de produtos processados, relativamente às de primários. Na UE, o aumento no valor das importações dos produtos brasileiros processados do café e da soja seria 75,4% maior com a eliminação da escalada tarifária do que com a redução conforme Doha. Na China, a possibilidade de eliminação da escalada tarifária também acarretaria em resultados mais expressivos que os obtidos pela redução: 27,4% a mais de farelo, e cerca de 100% e 107% no caso do óleo de soja em bruto e refinado, respectivamente. O objetivo complementar desse trabalho foi verificar os impactos do Diferencial Tributário de Exportação como instrumento para compensar os desestímulos ao processamento doméstico de produtos da soja resultantes da escalada tarifária nos mercados importadores. Assim, foram construídos cenários nacionais de tributação combinados com a aplicação de escalada tarifária nos mercados da UE e da China para verificar os impactos em termos de variação na margem de esmagamento do setor. Pelos resultados, a margem de esmagamento da soja esteve ampliada nos mercados importadores devido às tarifas de importação em: US$ 4,89 por tonelada (ou em 13%) na UE e US$ 14,46 (ou em 37%) na China, em média, em 2007. Na simulação de manutenção da taxação nacional como antes da Lei Kandir, a margem de esmagamento no Brasil poderia ter sido elevada em média em US$ 5,74 (ou 15%) durante o período analisado. Esse aumento teria sido suficiente para contrapor os efeitos da escalada tarifária da UE, mas não da China. O DTE argentino também foi considerado. No período analisado, o aumento da margem interna de esmagamento não se mostrou suficiente para contrabalançar totalmente os efeitos da escalada tarifária da China e da UE. Ainda assim, o aumento de margem proporcionado pôde favorecer o exportador argentino de produtos processados em detrimento do brasileiro na situação corrente. Considerando que, no caso da soja, a Argentina consiste no principal concorrente do Brasil e mantém uma política tributária que favorece a indústria doméstica de processamento em detrimento dos competidores, cabe a defesa do disciplinamento do DTE internacionalmente, além da eliminação da escalada tarifária nos mercados importadores.
Tariff escalation, which is the use of import tariffs that grow according to the processing level of a product, stimulates the imports of primary commodities rather than processed products in importing markets that apply this tool. This papers goal was to measure the gains to Brazil of the elimination of the tariff escalation in coffee products in EU, and soybean products in China and EU. In addition, it aimed to compare these gains to those obtained from the reduction of the tariff escalation, which is being proposed under WTOs Doha Round. Tariff cuts were simulated and trade gains were quantified through Laird e Yeats (1986) modeling of partial equilibrium. The results indicated that Doha negotiations could reduce the tariff escalation currently applied over coffee and soybean chains in the selected markets. However, they are not enough to eliminate them, which would require larger tariff cuts. The increase in EU imports of coffee and soybean processed products from Brazil due to tariff escalation elimination could be 75.4% higher than considering only its reduction under Doha. In China, the tariff escalation elimination would also imply in larger volume of imports than those obtained from the tariff reduction under Doha: 27.4% more of meal, and nearly 100% and 107% of soybean oil, crude and refined, respectively. This paper additional goal was to identify the impacts of the Differential Exports Taxes DTE as a tool to counterbalance the negative impacts over soybean exporting countries of the tariff escalation applied by importing markets. To achieve this goal, national scenarios of export taxes were built up and added to the tariff escalation in the EU and China in order to obtain the impacts in terms of variation of the sectors processing margin. According to the results, due to the import tariffs, the processing margin in the importing markets has been expanded as follows: in US$ 4.89 per tonne (or 13%) in the EU and in US$ 14.46 (or 37%) in China, along of 2007 in average. Simulating the national taxation such as before Kandir law, the soybeans processing margin in Brasil could have been raised by US$ 5.74 (or 15%) in average along of the analyzed period. That expansion would have been enough to compensate the effects of the tariff escalation of the EU, but not the one applied by China. The DTE for soybeans in Argentina was also considered. For the analyzed period, the increase in the internal processing margin was not enough to totally offset China and EU tariff escalation effects. Nevertheless, the raise in the domestic processing margin contributed to benefit the exporters of processed products in Argentina in detriment of the Brazilians in the current situation. Considering that, in the soybean case, Argentina is Brazils main competitor and the country keeps a national taxation structure that favors the domestic processing industry in prejudice of Brazilian industry, it is important to consider the defense of DTE stricter rules internationally, besides the elimination of the tariff escalation in the importing markets.

A análise da qualidade de grãos é um dos gargalos encontrados na cadeia produtiva do setor cafeeiro, tendo em vista que atualmente é feita de forma manual. Buscando uma solução para o problema, este trabalho apresenta um método baseado em visão computacional e redes neurais artificiais para identificar vinte e uma classes de grãos de café em amostras. No total, 421 atributos de três diferentes naturezas- morfologia, cor e textura- foram reunidos para compor o conjunto de características utilizado pela rede neural. Os atributos morfológicos são: Descritores de Fourier, Descritores Genéricos de Fourier, Momentos de Zernike, elementos do Modelo Autorregressivo e um conjunto de atributos diversos. Após avaliar duas abordagens para os atributos de cor- histogramas de frequências de cor e atributos estatísticos desses histogramas- a segunda foi escolhida e, assim, os atributos de cor adotados foram: média, variância, obliquidade, energia, curtose, entropia e suavidade de histogramas globais de cor, calculados para os espaços de cor RGB, HSV, I1I2I3 e CIELAB. Visando um melhor desempenho, os descritores de Haralick foram modificados para que dois pixels de referência fossem utilizados no cálculo da matriz de coocorrência. A versão modificada dos descritores superou as originais, e assim, seus valores calculados com o espaço de cor I1I2I3 (aquele que apresentou melhor eficácia em testes) foram utilizados como atributos de textura. O conjunto de atributos foi arranjado em cinco subconjuntos, cada um contendo diferentes combinações das distintas naturezas de atributos e sendo associado a uma análise. Para cada subconjunto selecionaram-se os melhores elementos pelas técnicas chi-quadrado, ganho de informação e PCA (Principal Component Analysis). O resultado dessa seleção determinou as entradas para três processos classificatórios, que foram avaliados a fim de se determinar o mais efetivo. Após as avaliações, e sendo determinada a melhor configuração, o processo classificatório escolhido proporcionou a acurácia de 85,08%, superando trabalhos correlatos.
The quality asssessment of beans is one of the bottlenecks found in the production chain of the coffee industry, as nowadays it is done manually. Seeking a solution for the problem, this work presents a method based on computer vision with neural networks to identify twenty-one classes of coffee beans in samples. In total, 421 features of three different types- morphological, colour and textural- were gathered to compose the feature set used by the neural network. The morphological features were Fourier Descriptors, Generic Fourier Descriptors, Zernike Moments, elements from Autoregressive Model and a miscellaneous set. After evaluating two approaches of colour features- colour frequency histograms and statistics from those histograms- the latter was chosen and the colour features comprised the mean, variance, skewness, kurtosis, energy, entropy and smoothness of global histograms calculated for the channels of the RGB, HSV, I1I2I3 and CIELAB colour spaces. Seeking better performance the Haralick features were modified, so two pixels were used as reference in the computation of the Grey Level Co-occurrence Matrix. The modified versions of the features outperformed the original ones and their computations with the I1I2I3 colour space (the one that provided the best results in tests) were used as textural features. The feature set was then rearranged in five intersecting subsets, each one containing different combinations of the feature types and being associated with an analysis. For each subset the best elements were selected using the techniques PCA (Principal Component Analysis), chi-squared and information gain. The resulting selections were used to determine the inputs to three classification processes, which were evaluated in order to select the most effective. After all evaluations, and having determined the best configuration, the selected classification process yielded an overall accuracy of 85.08%, outperforming related works.

2007/2008
Questo lavoro mirato allo studio dello sviluppo del seme di Coffea arabica, avvalendosi di differenti tecniche microscopiche, ha cercato di dare un contributo agli studi effettuati precedentemente da Houk (1938), Mendes (1941), Dedecca (1957), Wormer (1966), Dentan (1977, 1985) e De Castro (2002, 2005) che hanno apportato nozioni fondamentali a riguardo. Il campionamento del materiale è stato effettuato da settembre 2006 a giugno 2007 su piante appartenenti al cv. Mundo Novo, all’Instituto Agronômico di Campinas (IAC, SP, Brasil). Sono stati raccolti quindi circa 60 campioni per ciascun stadio di sviluppo a scadenza bisettimanale dal momento della fioritura fino a completa maturazione del frutto, per un totale di 34 settimane after anthesis (AA). I campioni sono stati quindi subito fissati e spediti in laboratorio a Trieste (Italia). Per prima cosa è stata effettuata l’analisi dimensionale delle drupe su un pool di campioni scelto casualmente tra quelli arrivati in laboratorio usando un calibro digitale lungo tre linee di misura: lunghezza, asse maggiore e asse minore in millimetri, sia per le drupe che per i semi. I campioni selezionati sono stati inclusi in resina Technovit 7100 (dall’inizio della fioritura fino alla 20a settimana AA) e tagliati con un microtomo rotativo (sezioni da 6 µm). I campioni dalla 22a settimana in poi sono stati tagliati invece con un criostato a bassa temperatura (da -15°C a -25°C; sezioni da 10-12 µm), a causa dell’aumento della durezza del materiale. Sulle sezioni preparate sono state usate tecniche standard di osservazione in microscopia (ottica, SEM e TEM) e colorazioni istochimiche (ad es. Toluidin blue-O, Periodic Acid Schiff, DAPI etc.) ed è stata effettuata una messa a punto di protocolli specifici secondo la tipologia di tessuto osservata. I risultati dell’analisi dimensionale hanno permesso di distinguere tre fasi di crescita dei frutti: 1. fase di quiescenza fino a 4 settimane dopo la fioritura (‘after anthesis’, AA); 2. fase centrale di sviluppo rapido (da 6 a 14 settimane AA); 3. fase di maturazione (da 16 settimane AA in poi). La seconda fase è strettamente correlata alle condizioni climatiche del periodo, in particolare all’aumento della frequenza delle piogge. Nella fase di crescita lenta l’ovario osservato in sezione longitudinale presenta la tipica struttura della drupa del caffè con due camere ovariche che ospitano un ovulo anatropo ciascuna. L’ovulo è composto da un funicolo, da un unico tegumento proveniente dal tessuto materno e da una zona di pochi micron occupata dal sacco embrionale non ancora sviluppato. E’ presente anche l’‘otturatore’ che, in Coffea, è di derivazione funicolare, formato da parenchima, conduce il tubetto pollinico al micropilo. Dopo circa un mese (4a -6a settimana) non si evidenzia ancora una crescita dimensionale del seme degna di nota. Durante la fase centrale di sviluppo rapido il mesocarpo si accresce fino ad uno spessore di 0,6 mm. A 8 settimane il seme ha 2 mm e il sacco embrionale fecondato ha iniziato il suo sviluppo con l’accrescimento dell’endosperma, inizialmente di tipo nucleare. A 10 settimane il seme ha 3 mm. Il sacco embrionale è più grande (0,2 mm) ed è formato da circa una ventina di cellule dell’endosperma. A 12 settimane il seme raggiunge i 10 mm. L’endosperma ha circa 1 mm. In questo stadio si nota un particolare strato tissutale che rappresenta la parte del perisperma che diventerà pellicola argentea. In seguito inizia ad intravedersi la pellicola argentea, con alcune cellule ancora vive e nucleate, e il pergamino si sta formando grazie a particolari modificazioni dell’endocarpo della drupa. Il seme ha quasi raggiunto la sua dimensione definitiva, alla 14a settimana. Nella fase di maturazione la crescita dimensionale non è più così degna di nota, mentre si osservano cambiamenti chimici e strutturali. La 16a settimana è caratterizzata dalla quasi completa formazione della pellicola argentea, anche all’interno del solco. Molte cellule dell’endosperma sono in attività mitotica continua. Il pergamino invece è completamente formato a 18 settimane, caratterizzato da fibre fusiformi a pareti spesse. Dalla 20a settimana in poi, il tessuto dell’endosperma ormai formato ha ancora le cellule a pareti sottili (3 µm). In questa fase delicata il materiale ha caratteristiche intermedie, né duro né molle; il contenuto vacuolare delle cellule endospermiche si arricchisce di corpi proteici e strutture zuccherine, evidenziate con diverse colorazioni. L’embrione è formato e anche le sue cellule sono ricche di corpi proteici, evidenziati soprattutto con la colorazione UV-Schiff e l’osservazione in fluorescenza. Le cellule dell’endosperma alla 26a settimana hanno un contenuto vacuolare ancora ricco di proteine e le pareti diventano più spesse (4-6 µm). Si osserva la formazione di alcune nodosità (Dentan, 1977) tipiche delle pareti cellulari dell’endosperma, soprattutto vicino alla cavità embrionale. Lo sviluppo del seme completo viene raggiunto alla 30a settimana, stadio in cui anche l’embrione sembra aver concluso la propria maturazione. Le pareti cellulari hanno raggiunto il loro spessore definitivo (da 6 a 10 µm). Infine, all’ultimo stadio (34 settimane AA), le cellule presentano un aspetto differente, risultano quasi più svuotate ed è difficile osservare i componenti cellulari con le colorazioni utilizzate fino ad ora. La maggior parte delle pareti presentano nodosità. Queste caratteristiche rappresentano uno stadio di sovra-maturazione della drupa. Oltre agli aspetti puramente morfo-anatomici, l’abilità di sezionare i tessuti seminali potrebbe essere di grande importanza per eventuali analisi biomolecolari di espressione genica, come già è stato in parte studiato recentemente (De Castro & Marraccini, 2006). Conoscere infatti gli stadi di sviluppo e i tessuti coinvolti in ciascuna fase, dà la possibilità di evitare errori grossolani di interpretazione dei risultati e di stabilire relazioni interessanti fra la parte genetica e le osservazioni in microscopia.
XXI Ciclo
1975

A long experiment has been established since 2000 at CATIE (Tropical Agricultural Research and Higher Education Center), Turrialba, Costa Rica. Twenty agro-forestry systems with different shade types and managements (organic and non-organic) consisting of an incomplete randomized block-design with shade tree as main effect and subplots represented by management were set up. The mean 13-year yield, bienniality index (BI) of coffee yield, pruning, shade cover and morphology (height, diameter, total branches and productive branches) of coffee plants in these agro-forestry systems were measured. The effects of different managements and shade types on the physical and chemical attributes of green coffee beans and aroma and colour generation of roasted coffee beans were investigated. The organic management always showed the more stable production, while the coffee yield and morphology were always worse under the intensive organic (IO) management than under the intensive conventional (IC) management. Comparing with the moderate conventional (MC) management, the intensive organic (IO) management did not only have a similar or even higher productivity, but it also had higher total lipid and protein in the green beans and a stronger ability to generate more flavour and colour. The full sun system had a higher total coffee yield and bienniality index (BI) of coffee yield, green bean density and total protein content and greater flavour generation and colour after roasting. Comparing with the timber system, the service system did not only have the higher coffee yield and better coffee plant morphology, but it also produced green beans with higher total protein and roasted beans with the more flavour and colour. Comparing with the non-legume shade tree, the legume shade tree only influenced the total protein content of green coffee beans and further improved the performance of flavour and colour in the roasted coffee beans.

In this research, physicochemical changes that took place during roast processing of coffee beans using fluidized air roaster were studied. The results showed that high-temperature-short-time resulted in higher moisture content, higher pH value, higher titratable acidity, higher porous structure in the bean cell tissues, and also produced more aldehydes, ketones, aliphatic acids, aromatic acids, and caffeine than those processed at low-temperature-long-time process. Fourier transform infrared (FTIR) spectroscopy and chemometric analysis showed that clusters for principal components score plots of ground coffee, extracted by a mixture of equal volume of ethyl acetate and water, were well separated. The research indicated that variations in IR-active components in the coffee extracts due to different stages of roast, roasting profiles, and geographical origins can be evaluated by the FTIR technique.
Natural Sciences and Engineering Research Council of Canada (NESRC) and Mother Parkers Tea & Coffee Inc.

Doutoramento em Bioquímica
Os polissacarídeos são os componentes maioritários dos grãos de café verde e torrado e da bebida de café. Os mais abundantes são as galactomananas, seguindo-se as arabinogalactanas. Durante o processo de torra, as galactomananas e arabinogalactanas sofrem modificações estruturais, as quais estão longe de estar completamente elucidadas devido à sua diversidade e à complexidade estrutural dos compostos formados. Durante o processo de torra, as galactomananas e arabinogalactanas reagem com proteínas, ácidos clorogénicos e sacarose, originando compostos castanhos de alto peso molecular contendo nitrogénio, designados de melanoidinas. As melanoidinas do café apresentam diversas atividades biológicas e efeitos benéficos para a saúde. No entanto, a sua estrutura exata e os mecanismos envolvidos na sua formação permanecem desconhecidos, bem como a relação estrutura-atividade biológica. A utilização de sistemas modelo e a análise por espectrometria de massa permitem obter uma visão global e, simultaneamente, detalhada das modificações estruturais nos polissacarídeos do café promovidas pela torra, contribuindo para a elucidação das estruturas e mecanismos de formação das melanoidinas. Com base nesta tese, oligossacarídeos estruturalmente relacionados com a cadeia principal das galactomananas, (β1→4)-Dmanotriose (Man3), e as cadeias laterais das arabinogalactanas, (α1→5)-Larabinotriose (Ara3), isoladamente ou em misturas com ácido 5-Ocafeoilquínico (5-CQA), o ácido clorogénico mais abundante nos grãos de café verde, e péptidos compostos por tirosina e leucina, usados como modelos das proteínas, foram sujeitos a tratamento térmico a seco, mimetizando o processo de torra. A oxidação induzida por radicais hidroxilo (HO•) foi também estudada, uma vez que estes radicais parecem estar envolvidos na modificação dos polissacarídeos durante a torra. A identificação das modificações estruturais induzidas por tratamento térmico e oxidativo dos compostos modelo foi feita por estratégias analíticas baseadas principalmente em espectrometria de massa, mas também em cromatografia líquida. A cromatografia de gás foi usada na análise de açúcares neutros e ligações glicosídicas. Para validar as conclusões obtidas com os compostos modelo, foram também analisadas amostras de polissacarídeos do café obtidas a partir de resíduo de café e café instantâneo. Os resultados obtidos a partir dos oligossacarídeos modelo quando submetidos a tratamento térmico (seco), assim como à oxidação induzida por HO• (em solução), indicam a ocorrência de despolimerização, o que está de acordo com estudos anteriores que reportam a despolimerização das galactomananas e arabinogalactanas do café durante a torra. Foram ainda identificados outros compostos resultantes da quebra do anel de açúcares formados durante o tratamento térmico e oxidativo da Ara3. Por outro lado, o tratamento térmico a seco dos oligossacarídeos modelo (individualmente ou quando misturados) promoveu a formação de oligossacarídeos com um maior grau de polimerização, e também polissacarídeos com novos tipos de ligações glicosídicas, evidenciando a ocorrência de polimerização através reações de transglicosilação não enzimática induzidas por tratamento térmico a seco. As reações de transglicosilação induzidas por tratamento térmico a seco podem ocorrer entre resíduos de açúcares provenientes da mesma origem, mas também de origens diferentes com formação de estruturas híbridas, contendo arabinose e manose como observado nos casos dos compostos modelo usados. Os resultados obtidos a partir de amostras do resíduo de café e de café instantâneo sugerem a presença de polissacarídeos híbridos nestas amostras de café processado, corroborando a ocorrência de transglicosilação durante o processo de torra. Além disso, o estudo de misturas contendo diferentes proporções de cada oligossacarídeo modelo, mimetizando regiões do grão de café com composição distinta em polissacarídeos, sujeitos a diferentes períodos de tratamento térmico, permitiu inferir que diferentes estruturas híbridas e não híbridas podem ser formadas a partir das arabinogalactanas e galactomananas, dependendo da sua distribuição nas paredes celulares do grão e das condições de torra. Estes resultados podem explicar a heterogeneidade de estruturas de melanoidinas formadas durante a torra do café. Os resultados obtidos a partir de misturas modelo contendo um oligossacarídeo (Ara3 ou Man3) e 5-CQA sujeitas a tratamento térmico a seco, assim como de amostras provenientes do resíduo de café, mostraram a formação de compostos híbridos compostos por moléculas de CQA ligadas covalentemente a um número variável de resíduos de açúcar. Além disso, os resultados obtidos a partir da mistura contendo Man3 e 5-CQA mostraram que o CQA atua como catalisador das reações de transglicosilação. Por outro lado, nas misturas modelo contendo um péptido, mesmo contendo também 5-CQA e sujeitas ao mesmo tratamento, observou-se uma diminuição na extensão das reações transglicosilação. Este resultado pode explicar a baixa extensão das reações de transglicosilação não enzimáticas durante a torra nas regiões do grão de café mais ricas em proteínas, apesar dos polissacarídeos serem os componentes maioritários dos grãos de café. A diminuição das reações de transglicosilação na presença de péptidos/proteínas pode dever-se ao facto de os resíduos de açúcares redutores reagirem preferencialmente com os grupos amina de péptidos/proteínas por reação de Maillard, diminuindo o número de resíduos de açúcares redutores disponíveis para as reações de transglicosilação. Além dos compostos já descritos, uma diversidade de outros compostos foram formados a partir dos sistemas modelo, nomeadamente derivados de desidratação formados durante o tratamento térmico a seco. Em conclusão, a tipificação das modificações estruturais promovidas pela torra nos polissacarídeos do café abre o caminho para a compreensão dos mecanismos de formação das melanoidinas e da relação estrutura-atividade destes compostos.
Polysaccharides are the major components of green and roasted coffee beans, and coffee brew. The most abundant ones are galactomannans, followed by arabinogalactans. During the roasting process, galactomannans and arabinogalactans undergo structural modifications that are far to be completely elucidated due to their diversity and complexity of the compounds formed. During the roasting process, galactomannans and arabinogalactans react with proteins, chlorogenic acids, and sucrose, originating high molecular weight brown compounds containing nitrogen, known as melanoidins. Several biological activities and beneficial health effects have been attributed to coffee melanoidins. However, their exact structures and the mechanisms involved in their formation remain unknown, as well as the structure-biological activity relationship. The use of model systems and mass spectrometry analysis allow to obtain an overall view and, simultaneously, detailed, of the structural modifications in coffee polysaccharides promoted by roasting, contributing to the elucidation of the structures and formation mechanisms of melanoidins. Based on this thesis, oligosaccharides structurally related to the backbone of galactomannans, (β1→4)-D-mannotriose, and the side chains of arabinogalactans, (α1→5)-Larabinotriose, alone or in mixtures with 5-O-caffeoylquinic acid, the most abundant chlorogenic acid in green coffee beans, and dipeptides composed by tyrosine and leucine, used as models of proteins, were submitted to dry thermal treatments, mimicking the coffee roasting process. The oxidation induced by hydroxyl radicals (HO•) was also studied, since these radicals seem to be involved in the modification of the polysaccharides during roasting. The identification of the structural modifications induced by thermal and oxidative treatment of the model compounds was performed mostly by mass spectrometry-based analytical strategies, but also using liquid chromatography. Gas chromatography was used in the analysis of neutral sugars and glycosidic linkages. To validate the conclusions achieved with the model compounds, coffee polysaccharide samples obtained from spent coffee grounds and instant coffee were also analysed. The results obtained from the model oligosaccharides when submitted to thermal treatment (dry) or oxidation induced by HO• (in solution) indicate the occurrence of depolymerization, which is in line with previous studies reporting the depolymerization of coffee galactomannans and arabinogalactans during roasting. Compounds resulting from sugar ring cleavage were also formed during thermal treatment and oxidative treatment of Ara3. On the other hand, the dry thermal treatment of the model oligosaccharides (alone or when mixed) promoted the formation of oligosaccharides with a higher degree of polymerization, and also polysaccharides with new type of glycosidic linkages, evidencing the occurrence of polymerization via non-enzymatic transglycosylation reactions induced by dry thermal treatment. The transglycosylation reactions induced by dry thermal treatment can occur between sugar residues from the same origin, but also of different origins, with formation of hybrid structures, containing arabinose and mannose in the case of the model compounds used. The results obtained from spent coffee grounds and instant coffee samples suggest the presence of hybrid polysaccharides in these processed coffee samples, corroborating the occurrence of transglycosylation during the roasting process. Furthermore, the study of mixtures containing different proportions of each model oligosaccharide, mimicking coffee bean regions with distinct polysaccharide composition, subjected to different periods of thermal treatment, allowed to infer that different hybrid and non-hybrid structures may be formed from arabinogalactans and galactomannans, depending on their distribution in the bean cell walls and on roasting conditions. These results may explain the heterogeneity of melanoidins structures formed during coffee roasting. The results obtained from model mixtures containing an oligosaccharide (Ara3 or Man3) and 5-CQA and subjected to dry thermal treatment, as well as samples derived from spent coffee grounds, showed the formation of hybrid compounds composed by CQA molecules covalently linked to a variable number of sugar residues. Moreover, the results obtained from the mixture containing Man3 and 5-CQA showed that CQA acts as catalyst of transglycosylation reactions. On the other hand, in the model mixtures containing a peptide, even if containing 5-CQA and subjected to the same treatment, it was observed a decrease in the extent of transglycosylation reactions. This outcome can explain the low extent of non-enzymatic transglycosylation reactions during roasting in coffee bean regions enriched in proteins, although polysaccharides are the major components of the coffee beans. The decrease of transglycosylation reactions in the presence of peptides/proteins can be related with the preferential reactivity of reducing residues with the amino groups of peptides/proteins by Maillard reaction, decreasing the number of reducing residues available to be directly involved in the transglycosylation reactions. In addition to the compounds already described, a diversity of other compounds were formed from model systems, namely dehydrated derivatives formed during dry thermal treatment. In conclusion, the identification of the structural modifications in coffee polysaccharides promoted by roasting pave the way to the understanding of the mechanisms of formation of melanoidins and structure-activity relationship of these compounds.

Os nematoides que atualmente tem sido classificados como P. coffeae, demonstram ampla variabilidade morfológica, molecular e quanto à reação à diferentes hospedeiros. Por conseguinte, é essencial que se identifique corretamente as espécies e que se conheça a capacidade de parasitismo em alguns hospedeiros, para que se possa estabelecer medidas de controle e estimar eventuais riscos da entrada de um patógeno em uma área com hospedeiro suscetível. Neste sentido, a presente pesquisa propõe, numa primeira parte, uma medida de controle de P. jaehni (K5), que é muito agressivo à cafeeiro arábico, baseada no uso de plantas má hospedeiras. Na segunda parte deste trabalho é realizada uma caracterização da reação de diferentes espécies vegetais à quatro populações de Pratylenchus spp. Em virtude do exposto, este estudo objetivou avaliar a reação de diferentes cultivares de feijoeiro comum frente à P. jaehni (K5), visando seu possível uso no manejo de áreas cafeeiras infestadas e caracterizar a reação de diferentes espécies vegetais de importância econômica (café, porta-enxertos cítricos, banana e sorgo) frente à quatro populações de Pratylenchus spp. As populações inciais utilizadas nos experimentos variaram entre 180 e 200 nematóides. Em todos os experimentos, os nematóides foram extraídos das raízes pelo método de Coolen e D´Herde (1972) e, eventualmente, do substrato pelo método de Jenkins (1964). Foram realizados três ensaios: i) o primeiro com feijoeiro comum, onde todas as cultivares utilizadas foram resistentes à P. jaehni (K5), inclusive na réplica; ii) o segundo com porta-enxertos cítricos, no qual somente o limão-cravo foi hospedeiro de P. jaehni (K5); iii) o terceiro, no qual foi utilizado café, limão-cravo, banana e sorgo para o conhecimento das respectivas reações frente à 4 populações de Pratylenchus spp. Neste último experimento ocorreu uma reação hospedeira diferenciada para cada população. De acordo com os resultados, concluise que as cultivares de feijoeiro comum utilizadas apresentam potencial de uso em áreas cafeeiras infestadas por P. jaehni (K5), em consórcio ou em áreas de renovação de cafezal, e que as populações de Pratylenchus spp. são capazes de se reproduzir de forma diferenciada frente às espécies vegetais testadas.
Nematode populations that have been classified as P. coffeae show wide morphological, molecular and host range variability. Therefore, is essential the correct identification of the species and the knowledge about its parasitism capacity on some hosts, to ensure appropriate control measures and to estimate the entry risks of a pathogen in an area with susceptible host. In this sense, the present research report, firstly, propose a control measure of P. jaehni (K5), which is very aggressive to the arabic coffee, based on the use of poor host plants. In the second part, was carried out a host status evaluation of different plant species to four populations of Pratylenchus spp. In this context, were evaluated the reaction of different common bean cultivars to P. jaehni (K5), for its possible use in management of coffee areas infested with this nematode, and characterized the response of different economic important plant species (coffee, citrus rootstocks, banana and sorghum) to four populations of Pratylenchus spp (IB01P, IB02P, K5 e C1). The initial population used in experiments ranged between 180 and 200 nematodes. In all experiments, nematodes were extracted from roots by Coolen e D\'Herde´s method (1972) and eventually from the substrate by Jenkins´ method (1964). Three assays were conducted and results was as following: i) in the first one, with common bean, all tested cultivars were resistant to P. jaehni (K5), including the replica; ii) in the second one, with rootstocks, only rangpur lime was a good host of P. jaehni (K5); iii) in the third one, in which was used coffee, rangpur lime, banana and grain sorghum, was observed a differential host reaction for each nematode population evaluated. According to the present results, we suggest that common bean cultivars tested have great potential for use, or in intercropping or in crop rotation, in coffee areas infested by P. jaehni (K5) and populations of Pratylenchus spp. have different reproductive fitness in the plants species tested.

In order to meet the demands of a European roaster interested in coffee produced by women, a Colombian coffee cooperative developed a female growers' program in 2000. Today this program has grown into an association of 390 women. This thesis evaluates how marketing strategies have impacted women's lives, gender roles, experiences of leadership, and expectations of improving profits as well as individual and communities living standards. In addition, it examines how women have taken advantage of gender equity, female leadership, and empowerment discourses as a marketing strategy. The lessons learned from the successes and challenges that these women have experienced is documented. This research examines how new circumstances and struggles have increased women's participation in coffee production and how these transformations have opened new opportunities for women in the market. The study is based on interviews with members of the Asociación de Mujeres Caficultoras Cauca, in the summer 2007.

O presente trabalho experimental focaliza o tema \"compostos fenólicos no café\". Dentre estes compostos se destacam os flavonóides, os ácidos clorogênico, cafêico, cafeilquinico, e seus isômeros. Na pesquisa foram avaliados quantitativamente, por espectrofotometria UV/VIS, as espécies fenólicas presentes após extração e complexação em amostras de cafés (cascas e sementes) com grãos em vários estágios de maturação. Foram obtidos valores na faixa de 10-6 mol.L-1 para fenóis totais nas cascas e nos grãos. O método de extração aqui proposto tornou-se bastante viável, sendo possível sua aplicação com tempo de preparo de amostras secas para análise de cerca de 40 minutos. As evidências experimentais decorrentes dessa pesquisa sugerem que tais espécies fenólicas (anti-oxidantes) podem ser aproveitadas de um material que é descartado (a casca do café), sendo, portanto um grande benefício econômico para a sustentabilidade do cultivo do café.
This experimental work has focused the theme \"Phelonic Compound in Coffee Beans\". Among these compounds have been shown flavonoids species, chlorogenic acid, caffeic acid, caffeinic acid and their isomer. The phelonic species has presented after extraction and complexation from coffee samples (peels and beans) using coffee beans in different grown and developed process has been evaluated in quantitative research by using UV/VIS Spectrophotometry Values have been got about 10-6 mol.L-1 in peels and beans. The proposed extraction method has been not only viable but its use possible with preparing time of dried samples for analyses in about 40 minutes. The experimental evidence resulting from this research has proposed that such phenolic antioxidant species can be made a good use of discarded material (the peel of coffee beans) therefore a great economical benefit for sustainable coffee cultivation.

Coffee is the most traded agricultural commodity in the world. Currently, Peru is considered the third principal producer of Coffea arabica in South America, and the sixth worldwide, accounting for 6 % of the global production. However, most of the coffee (~ 99 %) is exported as green beans due, in part, to the fact that the local quality control of the roasting process is not yet optimal. Hence, it is crucial to develop a more standardized process for the quality control of roasted coffee beans that will allow local Peruvian coffee farmers to introduce to the market a more valuable product. In the thesis presented here, work associated with the project FINCyT-PIPEI-PUCPCENFROCAFE- 2012 on the quantitation of the main compounds developed during the roasting process was embraced using NMR and HPLC-DAD methodologies. Attention was focused on the secondary metabolites that, from a flavor-aroma perspective, are of interest: caffeine, 5- caffeoylquinic acid, trigonelline, 1-methylpyridinium ion and nicotinic acid, and 5- hydroxymethylfurfural as a marker of deterioration. One- and two-dimensional NMR techniques allowed the simultaneous identification of eleven compounds known to be associated with the flavor and aroma of coffee. The NMR quantitation of five compounds was performed using ERETIC2 and Standard Calibration Curves and the results were validated by a new HPLC methodology, which constitutes the only validated methodology currently available for the simultaneous quantitation of these five compounds. The percentage difference among this three methods was within acceptable values (1 – 20%) for most of the compounds. It was demonstrated that these numbers were sample dependent. In addition, PCA analyses of quantitative data (NMR and HPLC-DAD) allowed the discrimination of coffee samples acording to the degree of roasting, as well as to their origin (instant coffee, speciality coffees from different regions in Peru). Hence, these preliminary results indicate that NMR and HPLC can be used as quality control tools to optimize the roasting conditions of Peruvian specialty coffee. Recommendations are included in this work to improve further the error percentages between the NMR and HPLC data that in some cases (for 5-caffeoylquinic acid and nicotinic acid) were high.
Tesis

Made available in DSpace on 2014-06-11T19:24:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-09-21Bitstream added on 2014-06-13T20:32:11Z : No. of bitstreams: 1 huamanimelendez_vj_me_sjrp_parcial.pdf: 569064 bytes, checksum: a421744f281164e37617b166ac6f3843 (MD5) Bitstreams deleted on 2014-10-03T16:24:34Z: huamanimelendez_vj_me_sjrp_parcial.pdf,Bitstream added on 2014-10-03T16:27:33Z : No. of bitstreams: 2 huamanimelendez_vj_me_sjrp_parcial.pdf.txt: 53713 bytes, checksum: 111b3a17f7877d22607c79773592bd40 (MD5) 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) Bitstreams deleted on 2014-10-03T16:33:11Z: 000698203.pdf,Bitstream added on 2014-10-03T16:43:25Z : No. of bitstreams: 2 huamanimelendez_vj_me_sjrp_parcial.pdf.txt: 53713 bytes, checksum: 111b3a17f7877d22607c79773592bd40 (MD5) 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) Bitstreams deleted on 2014-10-03T16:48:51Z: 000698203.pdf,Bitstream added on 2014-10-03T16:49:44Z : No. of bitstreams: 1 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5) Bitstreams deleted on 2014-10-27T11:47:01Z: 000698203.pdf,Bitstream added on 2014-10-27T11:48:02Z : No. of bitstreams: 1 000698203.pdf: 2310634 bytes, checksum: 632d409df815fe5814967be2a2659bf4 (MD5)
Oea
A presente pesquisa propõe como alternativa melhorar o processo de extração da cafeína dos grãos de café de variedade arábica utilizando água como solvente com auxílio de ultrassom de alta intensidade. Na primeira etapa da pesquisa foram avaliadas propriedades físicas do grão no processo de hidratação e a proposição da solução analítica para a semiesfera da equação de Fick. Na segunda etapa foi avaliado o coeficiente de difusão da cafeína no processo de extração com água em diferentes temperaturas (30, 40, 50 e 60 °C). Na terceira etapa foi empregado um delineamento composto central rotacional para avaliar a porcentagem de recuperação e o coeficiente de difusão de cafeína nos grãos de café, para os tempos de 15, 30 e 60 minutos sob a influência do ultrassom de alta intensidade (30, 45, 65, 85 e 100% da amplitude da potência) em diferentes ciclos de aplicação (30, 45, 65, 85 e 100%) e em função da temperatura de extração (30, 36, 45, 53 e 60 °C). O modelo matemático para geometria semiesférica apresentou melhor ajuste aos dados experimentais, tanto para a difusão de água nos grãos de café no processo de hidratação, como para o processo de extração de cafeína em meio aquoso. O coeficiente de difusão de água no grão de café no processo de hidratação variou de 6,901 .10-11 m2 s-1 a 30 °C até 3,119 .10-10 m2 s-1 a 60 °C, com energia de ativação de 41,243 kJ mol-1. Para a difusão da cafeína, o modelo matemático para semiesfera também resultou ser ligeiramente superior na maioria dos casos, onde o coeficiente de difusão variou de 1,026 .10-11 m2 s-1 a 30 °C até 9,004 .10-11 m2 s-1 a 60 °C com uma energia de ativação de 59,933 kJ mol-1. Na aplicação de ultrassom de alta intensidade, os fatores de potência de ultrassom e a temperatura...
This research proposes as an alternative to improve the process of extracting caffeine from coffee beans, arabica variety, using water as solvent, assisted by high-intensity ultrasound. In the first stage of the research, physical properties of the grain were evaluated in the hydration process and the proposition of an analytical solution for the semi-sphere of the Fick equation. In the second stage, it was determined the diffusion coefficient of caffeine in the extraction process with water at different temperatures (30, 40, 50 and 60 °C). In the third stage, a central composite rotational design was used to assess the percentage of recovery and the diffusion coefficient of caffeine in coffee beans, for caffeine extraction upon different treatment times (15, 30 and 60 minutes) under the influence of high-intensity ultrasound (30, 45, 65, 85 and 100% of the power amplitude), different application cycles (30, 45, 65, 85 and 100%), as a function of the temperature (30, 36, 45, 53 and 60 °C). The mathematical model presented by the semispherical geometry showed the best fit to the experimental data, in comparison to Fick's sphere geometry approach, both for the diffusion of water in the coffee beans in the hydration process, and for the extraction process of caffeine in aqueous media. The diffusion coefficient of water in the coffee bean in the hydration process ranged from 6.901 ×10-11 m2 s-1 at 30°C to 3.119 ×10-10 m2 s-1 at 60°C, with and activation energy of 41.243 kJ mol-1. For the diffusion of caffeine in the grain, the semi-sphere mathematical model also resulted slightly better fitting in most cases, with a diffusion coefficient ranged from 1.026 ×10-11 m2 s-1 at 30°C to 9.004 10-11 m2 s-1 at 60°C, and an activation energy of 59.933 kJ mol-1. In the high-intensity ultrasound assisted extraction process, the ultrasound... (Complete abstract click electronic access below)

Coffee is an important beverage product in many parts of the world. During the production and processing of coffee the prevailing environmental factors and rate of drying can have a profound influence on colonisation by mycotoxigenic fungi and contamination with ochratoxin A (OTA). In Kuwait, coffee beans are imported from various parts of the world. The objectives of this project were to (a) to examine the diversity of mycotoxigenic fungi found in green and roasted coffee beans bought in the Kuwaiti market from different source countries and identify the dominant fungal populations, (b) to examine the ecology and ochratoxin A production by the ochratoxigenic strains and species isolated, (c) determine the effect of caffeine concentrations in vitro on growth and OTA production by strains from the Aspergillus section Circumdati and Section Niger groups, (d) evaluate the impact of interacting climate change factors (water activity (aw) x temperature x elevated CO2) on growth and OTA production in vitro and in situ, (e) determine the effect of aw and temperature interactions on ecology of strains of two new species, A. aculeatinus and A. sclerotiicarbonarius, isolated from coffee beans and (f) evaluate the efficacy of gaseous ozone (O3) for controlling OTA producing fungi and control of contamination in coffee beans after treatment and after storage. Cont/d.

Orientador: Roger Darros Barbosa
Banca: Maria Aparecida Mauro
Banca: Fernando Antonio Cabral
Resumo: A presente pesquisa propõe como alternativa melhorar o processo de extração da cafeína dos grãos de café de variedade arábica utilizando água como solvente com auxílio de ultrassom de alta intensidade. Na primeira etapa da pesquisa foram avaliadas propriedades físicas do grão no processo de hidratação e a proposição da solução analítica para a semiesfera da equação de Fick. Na segunda etapa foi avaliado o coeficiente de difusão da cafeína no processo de extração com água em diferentes temperaturas (30, 40, 50 e 60 °C). Na terceira etapa foi empregado um delineamento composto central rotacional para avaliar a porcentagem de recuperação e o coeficiente de difusão de cafeína nos grãos de café, para os tempos de 15, 30 e 60 minutos sob a influência do ultrassom de alta intensidade (30, 45, 65, 85 e 100% da amplitude da potência) em diferentes ciclos de aplicação (30, 45, 65, 85 e 100%) e em função da temperatura de extração (30, 36, 45, 53 e 60 °C). O modelo matemático para geometria semiesférica apresentou melhor ajuste aos dados experimentais, tanto para a difusão de água nos grãos de café no processo de hidratação, como para o processo de extração de cafeína em meio aquoso. O coeficiente de difusão de água no grão de café no processo de hidratação variou de 6,901 .10-11 m2 s-1 a 30 °C até 3,119 .10-10 m2 s-1 a 60 °C, com energia de ativação de 41,243 kJ mol-1. Para a difusão da cafeína, o modelo matemático para semiesfera também resultou ser ligeiramente superior na maioria dos casos, onde o coeficiente de difusão variou de 1,026 .10-11 m2 s-1 a 30 °C até 9,004 .10-11 m2 s-1 a 60 °C com uma energia de ativação de 59,933 kJ mol-1. Na aplicação de ultrassom de alta intensidade, os fatores de potência de ultrassom e a temperatura... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: This research proposes as an alternative to improve the process of extracting caffeine from coffee beans, arabica variety, using water as solvent, assisted by high-intensity ultrasound. In the first stage of the research, physical properties of the grain were evaluated in the hydration process and the proposition of an analytical solution for the semi-sphere of the Fick equation. In the second stage, it was determined the diffusion coefficient of caffeine in the extraction process with water at different temperatures (30, 40, 50 and 60 °C). In the third stage, a central composite rotational design was used to assess the percentage of recovery and the diffusion coefficient of caffeine in coffee beans, for caffeine extraction upon different treatment times (15, 30 and 60 minutes) under the influence of high-intensity ultrasound (30, 45, 65, 85 and 100% of the power amplitude), different application cycles (30, 45, 65, 85 and 100%), as a function of the temperature (30, 36, 45, 53 and 60 °C). The mathematical model presented by the semispherical geometry showed the best fit to the experimental data, in comparison to Fick's sphere geometry approach, both for the diffusion of water in the coffee beans in the hydration process, and for the extraction process of caffeine in aqueous media. The diffusion coefficient of water in the coffee bean in the hydration process ranged from 6.901 ×10-11 m2 s-1 at 30°C to 3.119 ×10-10 m2 s-1 at 60°C, with and activation energy of 41.243 kJ mol-1. For the diffusion of caffeine in the grain, the semi-sphere mathematical model also resulted slightly better fitting in most cases, with a diffusion coefficient ranged from 1.026 ×10-11 m2 s-1 at 30°C to 9.004 10-11 m2 s-1 at 60°C, and an activation energy of 59.933 kJ mol-1. In the high-intensity ultrasound assisted extraction process, the ultrasound... (Complete abstract click electronic access below)
Mestre

Made available in DSpace on 2016-12-23T14:37:36Z (GMT). No. of bitstreams: 1 Marcos Moulin Teixeira.pdf: 1978246 bytes, checksum: 2e2ea29a5d955ce66c6afc0ece542ef0 (MD5) Previous issue date: 2011-06-29
The Espírito Santo State emerges as the largest producer of conilon coffee, contributing with 72% of national production. Innovative production technologies were developed and refined by the Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural and partners. However, in the area of post-harvest there are few scientific studies. Thus, this study assesses the relationship of different forms of post-harvest processing of conilon coffee with product quality, operating costs and eventual profitability. Data were collected in the Unidade Regional de Cafés Especiais Conilon- Sul (URCE-SUL), located in the municipality of Mimoso do Sul in the South of Espírito Santo state. The experiment consisted of six treatments and conducted in a randomized block design with four replications. Treatments consisted of: i) Traditional Terrace(TT);(ii) Traditional Dryer (TD),(iii) Washed Terrace (LT; (iv) Washed Dryer (WD) (v) Pulped Coffee Cherry Beans Terrace (PCCT), and (vi) Pulped Dryer (CDS). Represented by different harvest seasons (06/10, 06/16, 06/22 and 07/01) in the year 2010. The percentage of fruits and buoys ratio between ripe and green, drying time and its respective quantity processed, the costs and profitability of coffee processed in different post-harvest treatments was determined. The drying was made on a terrace paved with cement and rotary dryer of indirect fire. The processing of coffee from all treatments was made on a single machine, when coffee was 13% humidity. Under the conditions that study was conducted, it can conclude that: a) at the beginning of the harvest there is the lowest percentage of buoys and ripe fruits and a higher percentage of green fruit, b) pulped coffee cherry beans presents the lowest drying time and greater volume of coffee obtained by drying unit, both on a terrace paved with cement and in dryer; c) the cost of drying in machine is higher than the cost of the drying in terrace, within the same mode of post-harvest process, d) labor is the component of operating cost with the highest weight, e) the lowest cost infrastructure is in the process of post-harvest traditional terrace and the largest is the pulped coffee cherry beans dryer; f) the process of post-harvest is more profitable pulped coffee cherry beans with the drying terrace and lower profitability of the process is the washed with drying machine, g)the largest number of defects appears in the traditional treatment that not received terrace processing, called natural drying in the open; and, h) in sensory scale conilon coffee, all the coffees are classified as recommended for consumption, and the pulped coffee cherry beans dry in dryer and terrace are gourmet and other treatments are superior.
O Estado do Espírito Santo destaca-se como o maior produtor brasileiro de café conilon, contribuindo com 72% da produção nacional. Tecnologias inovadoras de produção foram desenvolvidas e aprimoradas no estado pelo Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural e instituições parceiras. Contudo, na área de pós-colheita verificam-se poucos estudos científicos. Assim, este trabalho avalia a relação de diferentes formas de processamento de pós-colheita de café conilon com a qualidade do produto, custos de operações e rentabilidade final. Os dados foram coletados na Unidade Regional de Cafés Especiais Conilon- Sul (URCE-SUL), localizada no município de Mimoso do Sul ES. O experimento foi montado num delineamento de blocos casualizados com seis tratamentos e quatro repetições. Os tratamentos consistiram de: i)Tradicional Terreiro (TT); (ii) Tradicional Secador (TS); (iii) Lavado Terreiro (LT); (iv) Lavado Secador (LS); (v) Cereja Descascado Terreiro (CDT); e (vi) Cereja Descascado Secador (CDS). As repetições foram realizadas em diferentes épocas de colheita (10/06; 16/06; 22/06 e 01/07) do ano de 2010. Foi determinada a percentagem de frutos boias e a relação percentual entre maduros e verdes, o tempo de secagem e sua respectiva quantidade processada, os custos e a rentabilidade do café processado em diferentes tratamentos de pós-colheita. As secagens foram feitas em terreiro pavimentado de cimento e em secador rotativo de fogo indireto. O beneficiamento do café de todos os tratamentos foi feito em uma única máquina, quando o café estava com 13% de umidade. Nas condições em que foi realizado este estudo, pode-se concluir que: a) no início da colheita há menor percentual de frutos boias e maduros e maior percentual de frutos verdes; b) o café cereja descascado apresenta o menor tempo de secagem e o maior volume de café obtido por unidade de secagem, tanto em terreiro pavimentado de cimento quanto em secador; c) o custo da secagem em secador é superior ao custo da secagem em terreiro, dentro da mesma modalidade do processo de pós-colheita; d) a mão de obra é o componente do custo operacional que apresenta maior peso; e) o menor custo em infraestrutura é do processo de pós-colheita tradicional terreiro e o maior é do cereja descascado secador; f) O processo de pós-colheita com maior rentabilidade é o cereja descascado com secagem em terreiro e a menor rentabilidade é do processo lavado com secagem em secador; g) o maior número de defeitos aparece no tratamento tradicional terreiro que não recebeu processamento, chamado natural e com secagem a céu aberto; e, h) na escala sensorial para café conilon, todos os cafés são classificados como recomendáveis para o consumo, sendo que os cerejas descascados em secador e em terreiro são gourmet e os demais tratamentos são superior.

Šio darbo tiksas - nustatyti ochratoksino A kiekius žaliose ir skrudintose kavos pupelėse. Mėginiai tyrimams buvo paimti iš dviejų Lietuvos kavos skrudinimo įmonių. Kavos pupelių mėginiai buvo iš Amerikos, Afrikos ir Azijos. Žalių kavos pupelių užterštumas ochratoksinu A buvo 1,0 – 3,5 µg/kg, o po skrudinimo jis padidėjo 14,12 – 63,64%. Taip pat buvo identifikuojami ochratoksiną A gaminantys grybai ir skaičiuojami jų kolonijas sudarantys vienetai. Nustatyta, kad kavos pupelės buvo užterštos A. niger, A. ochraceus, A. parasiticus, A. sydowii ir A. flavus.
The experiments was done in LUHS VA in the Animal Welfare Reaserch Laboratory. The aim of this study were to determinate ochratoxin A amounts in green and roasted coffee beans. Samples were taken from two coffee roasters companies in Lithuania. Coffee samples were from America, Asia and Africa. The determination of OTA in green coffee samples was 1,0 – 3,5 µg/kg, but after roasting it increase to 14,12 – 63,64%. Also were identified OTA-producing species of fungi and their colony formed quantities. It was found that determination of fungi were 50% of A. niger colonies, other 50% were of A. ochraceus, A. parasiticus, A. sydowii and A. flavus.

Submitted by RENAN JOSE PARECIDO null (renanjparecido@hotmail.com) on 2016-09-14T02:13:02Z No. of bitstreams: 1 DISSERTAÇÃO Renan-FINAL.pdf: 2751419 bytes, checksum: 77b761a96ce4657834f44a8281d103ca (MD5)
Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-16T21:24:01Z (GMT) No. of bitstreams: 1 parecido_rj_me_bot.pdf: 2751419 bytes, checksum: 77b761a96ce4657834f44a8281d103ca (MD5)
Made available in DSpace on 2016-09-16T21:24:01Z (GMT). No. of bitstreams: 1 parecido_rj_me_bot.pdf: 2751419 bytes, checksum: 77b761a96ce4657834f44a8281d103ca (MD5) Previous issue date: 2016-07-28
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Na fase inicial da cultura do café arábica (Coffea arabica L.), as exigências nutricionais aumentam rapidamente com a entrada em produção (primeira safra), época em que se deve ter cuidado na nutrição das plantas, pois os cafeeiros produzem muito, ainda com pouca folhagem (baixa relação folha/fruto). O nitrogênio (N) é o nutriente mais exigido pelo cafeeiro. O silício (Si) desempenha diversos efeitos benéficos às plantas, e supõe-se que possa melhorar o aproveitamento do N fornecido. Dessa forma, objetivou-se com o presente trabalho avaliar o efeito da aplicação de Si via foliar e doses de N via solo no crescimento, nutrição e produtividade inicial da cultura do café arábica. O experimento foi conduzido em uma área cultivada com cafeeiro arábica, cultivar Catuaí IAC 99, localizado no município de Manduri-SP, em um solo Latossolo Vermelho Amarelo distrófico. Foi adotado o delineamento em blocos casualizados, em esquema fatorial 4 x 2, com quatro repetições. Os tratamentos foram constituídos por quatro doses de N (0, 75, 150 e 300 kg ha-¹) com presença e ausência de aplicação Si via foliar. A fonte de N utilizada foi o nitrato de amônio. O Si foi aplicado na dose de 2 L ha-¹do produto Silamol®. O experimento foi conduzido durante o período de 39 meses após o plantio dos cafeeiros no campo. A adubação nitrogenada aumentou a altura da planta, o número de nós nos ramos plagiotrópicos e colaborou na manutenção do enfolhamento das plantas, na fase de formação da lavoura. A aplicação das maiores doses de N atrasou a maturação dos frutos e incrementou a produtividade e o tamanho dos grãos da cultura do café. Nas duas primeiras safras, a produtividade de grãos beneficiados da cultura do café arábica foi incrementada até doses de N que variaram de 246 a 300 kg ha-¹. A aplicação de Si via foliar proporcionou maior altura das plantas e número de nós nos ramos plagiotrópicos, especialmente na ausência da aplicação de N em cobertura. Na presença das maiores doses de N, o fornecimento de Si via foliar proporcionou maiores teores de N na folha e maior produtividade de grãos na cultura do café arábica.
In the initial phase of the Arabica coffee (Coffea arabica L.), the nutritional requirements increase rapidly with the entry into production phase (first harvest), the time when one should be careful in plant nutrition, because the coffee plants produce a lot, even with little foliage (low leaf/fruit ratio). Nitrogen (N) is the nutrient most required by the coffee plant. Silicon (Si) plays various beneficial effects to plants and it is assumed that can improve the use of N provided. Thus, the aim of the present study was to evaluate the effect the foliar application of Si and N rates applied to soil on growth, nutrition and initial bean yield of Arabica coffee crop. The experiment was conducted in an area cultivated with Arabica coffee, cultivar Catuaí IAC 99, located in the municipality of Manduri-SP, in a dystrophic Red Yellow Latosol. The experimental design was a randomized blocks in a factorial 4 x 2, with four replications. The treatments consisted of four N rates (0, 75, 150, and 300 kg ha-¹) and presence and absence of foliar application of Si. Nitrogen source used was ammonium nitrate. The Si was applied at the rate of 2 L ha-¹ Silamol® product. The experiment was conducted during the period of 39 months after planting of coffee plants in the field. Nitrogen fertilization increased the plant height, number of nodes in plagiotrophycal branches and collaborate in maintenance of leafiness of plants in the crop formation phase. The Application of N rates largest delayed the ripening of the fruit and increased yield and the size of bean of the Arabica coffee crop. In the first two harvests, the hulled green-bean yield of Arabica coffee crop was increased by N rates ranging from 246 to 300 kg ha-¹. The foliar application of Si provided greater plant height and number of nodes in plagiotrophycal, especially in the absence of N fertilization. In the presence of higher N rates, the supply of Si via foliar provided higher concentrations of N in leaf and higher grain yield of Arabica coffee crop.

Por meio do método lattice Boltzmann (LBM), este projeto de pesquisa propõe a simulação computacional da extração dos compostos diterpênicos do café verde em sistemas com fluido pressurizado. Para isso foi adotado um modelo fenomenológico dinâmico e de primeira ordem quanto à dependência espacial. Usando a rede D1Q2, o LBM foi implementado com duas funções de distribuição de partículas, acompanhadas das respectivas funções de distribuição de equilíbrio. Cada função refere-se à concentração em uma dada fase (sólida e fluida). A previsão das curvas de rendimento pressupõe o conhecimento dos parâmetros do processo, tais como a difusividade mássica interna (intrapartícula), o coeficiente de partição volumétrica e a difusividade mássica axial. Para o devido ajuste destes parâmetros contra dados experimentais, foi desenvolvido um código computacional utilizando a técnica de gradiente descendente. Resultados numéricos das simulações foram comparados com dados experimentais e mostraram-se satisfatórios. Adicionalmente, foi realizada a análise da influência dos parâmetros supracitados mediante a criação de uma interface gráfica amigável para o código computacional original. Este projeto de pesquisa, além de fomentar a agregação de valor ao café, desenvolveu competências em modelagem e simulação de processos de extração de espécies químicas a partir de métodos numéricos.
Using the lattice Boltzmann method (LBM), this research project proposes a computer simulation of diterpene compounds extraction from green coffee beans in high pressure fluid systems. In order to do so, a dynamic phenomenological model with first-order spatial dependence was adopted. LBM was implemented on D1Q2 lattice, using two particle distribution functions, followed by the respective equilibrium distribution functions. Each function refers to the extract concentration in each phase, namely solid and fluid. Prediction of extract yield curves relies on process parameters such as internal (i.e., intraparticle) mass diffusivity, volumetric partition coefficient and axial mass diffusivity. Values of aforesaid parameters were fitted against experimental data via descendent gradient technique coupled to the LBM computer code and numerically simulated result were consistent. Besides modeling and simulation, this project performed the influence analysis of those process parameters. To this end, a user-friendly graphical interface for the original computer code was created. While fostering value to be added to coffee, this research project develops skills in modeling and simulation of chemical species extraction through numerical methods.

Inseticidas e fungicidas geralmente são estudados quanto a sua eficiência no controle de pragas e doenças, entretanto podem provocar efeitos fisiológicos pouco conhecidos capazes de influenciar o desenvolvimento das culturas. O tiametoxam é um inseticida sistêmico do grupo dos neonicotinóides, da família nitroguanidina, que atua no receptor nicotínico acetilcolina de insetos, danificando o sistema nervoso dos mesmos, levando-os à morte. Este inseticida, largamente utilizado no controle de pragas iniciais e insetos sugadores, apresenta efeito bioativador, uma vez que mesmo na ausência da pragas, promove aumento em vigor e desenvolvimento nas plantas tratadas. Acredita-se que os efeitos do tiametoxam em plantas são indiretos, pois atuam na expressão dos genes responsáveis pela síntese e ativação de enzimas metabólicas, relacionadas ao crescimento da planta, alterando a produção de aminoácidos e precursores de hormônios vegetais. Existem alguns trabalhos com tiametoxam com o objetivo de verificar seus efeitos no metabolismo e desenvolvimento das plantas, mas os resultados ainda não são claros, evidenciando forte interação entre cultivares, épocas, condições de estresse e disponibilidade de nutrientes. Em função da grande utilização do inseticida tiametoxam na agricultura brasileira, o estudo deste agroquímico, no sentido de alterar o metabolismo e desenvolvimento de plantas, constitui-se de grande importância na agregação de informações à literatura biológica e agronômica. Os objetivos deste trabalho foram verificar o efeito da aplicação de tiametoxam em plantas de cana-de-açúcar, feijoeiro, soja, laranjeira e cafeeiro, em diferentes doses e formas de aplicação (tratamento de sementes, pulverização foliar e aplicação no solo), sobre parâmetros de desenvolvimento (área foliar, massa seca de folhas e raízes, comprimento radicular) e aspectos bioquímicos (teores foliares de nutrientes e atividade enzimática). Os experimentos foram realizados em vasos, no Horto Experimental do Departamento de Ciências Biológicas da ESALQ/USP. Concluiu-se que a aplicação de tiametoxam em pulverização foliar, em cana-deaçúcar, aumenta a área foliar e o comprimento das raízes, amplia a espessura do córtex da raiz, incrementa o diâmetro do cilindro vascular e aumenta o número de metaxilemas; em feijoeiro, em tratamento de sementes, aumenta a área foliar, a massa seca da parte aérea e a atividade da nitrato redutase em folhas e em pulverização foliar aumenta a atividade da nitrato redutase e a atividade da fenilalanina amônia-liase em folhas; em soja, em tratamento de sementes, aumenta a área foliar, massa seca e comprimento das raízes e os teores foliares de cálcio e magnésio, e em pulverização foliar, reduz os teores de fósforo e cálcio, mas aumenta os teores de potássio; em mudas de laranjeira, aplicado no solo, aumenta a área foliar, a massa seca das folhas, a massa seca do caule e ramos e a área foliar média, mas reduz os teores foliares de nitrogênio, fósforo e enxofre; em mudas de café arábica, aplicado na raiz, aumenta o número de folhas, a massa seca de raízes finas e o comprimento das raízes.
Insecticides and fungicides are often studied to their efficiency in controlling pests and diseases, however can cause physiological effects little known that can affect crop growth. Thiamethoxan is a systemic insecticide from the neonicotinoid group, nitroguanidine family, which acts on nicotinic acetylcholine receptor of insects, damaging their nervous system, leading them to death. This insecticide, that is widely used for controlling pests and sucking insects, has bioactivator effect, since even in the absence of pests, promotes an increase in vigor and development in treated plants. It is believed that the effects of thiamethoxan in plants are indirect, because it acts in the genes expression responsible for metabolic enzymes activation and synthesis, related to plant growth, by modifying amino acids and plant hormones precursors production. There is a number of studies with thiamethoxan in the way to determine the effects on metabolism and development of plants, but the results are not clear, showing strong interaction between cultivars, stress conditions and nutrient availability. Due to the wide use of the insecticide thiamethoxan in Brazilian agriculture, the study of this insecticide in order to know the metabolism changes in the plants, brings a great importance in the collection of knowledge to the agronomic and biological literature. The objectives of this study was to evaluate the effect of thiamethoxan on sugar cane, common beans, soy, orange and coffee plants with different doses and forms of application (seed treatment, foliar spray and soil application) on developmental parameters (leaf area, dry mass of leaves and roots, root length) and biochemical aspects (nutrient content and enzymatic activity). The experiments were conducted in pots in the ESALQ / USP, Experimental Field of Biological Sciences Department. It was concluded that the application of thiamethoxan as foliar spray on sugar cane, increases leaf area and root length, increases the thickness of the cortex of the root, increases the diameter of the vascular cylinder and increases the number of vessels; in bean for seed treatment, increases the leaf area, dry mass of shoots and the activity of nitrate reductase in leaves, and foliar spray increases the activity of nitrate reductase and phenylalanine ammonia-lyase in leaves; in soybean, in seeds treatment, increases leaf area, dry weight of roots, root length and foliar calcium and magnesium, and foliar spray, reduces the amount of phosphorus and calcium, but increased levels of potassium; in orange trees, applicated on the soil, increases the leaf area, leaf area average, leaves dry mass, stems and branches dry mass, but reduces the amount of nitrogen, phosphorus and sulfur in the leaf; in arabica coffee seedlings, applied at the root, increases the number of leaves, fine roots dry mass and length of roots.

Les jonctions tunnel magnétiques épitaxiées Fe/MgO/Fe(001) présentent des comportements remarquables dans la limite des faibles ou des fortes épaisseurs de MgO. Ainsi, dans le premier cas, une interaction antiferromagnétique entre les deux couches de fer est observée ; dans le second, des effets de filtrage en symétrie conduisent à l'obtention de fortes valeurs de magnétorésistance. Les expériences réalisées au cours de cette thèse visent à étudier et mettre en relation ces deux régimes de propriétés extrêmes. Des analyses en tension et en température nous permettent d'étudier les conséquences d'une modulation de la structure cristalline des électrodes et/ou de l'interface sur le transport polarisé en spin. Dans ce cadre, nous nous intéressons à trois systèmes : des jonctions hybrides Fe/MgO(001)/CoFeB, où l'électrode de CoFeB est déposée par pulvérisation cathodique puis cristallisée in situ, des jonctions Fe/MgO/Fe à texture (001), ainsi que des jonctions Fe/MgO/Fe monocristallines présentant une rugosité artificielle à l'interface barrière/électrode. Le couplage antiferromagnétique dans des systèmes Fe/MgO/Fe(001) à barrière fine est étudié grâce à des mesures de magnétométrie sur la gamme de température [5 K ; 500 K]. Nous considérons aussi l'effet de modifications structurales et/ou chimiques de l'interface par le biais de l'introduction d'une rugosité contrôlée ou d'un contaminant. Les résultats les plus originaux de cette thèse sont obtenus grâce à l'introduction d'une rugosité artificielle à l'interface Fe/MgO ; contre toute attente, ce désordre contrôlé peut en effet augmenter l'effet de magnétorésistance ou l'intensité du couplage antiferromagnétique.

碩士
國立清華大學
材料科學工程學系
105
In this paper, caffeine extraction and coffee diffusion in water have been discussed. For some people, caffeine can bring about unpleasant symptoms such as nervousness, headache, and palpitation. The decaffeination processes were therefore developed to remove caffeine and keep the flavors locked in the coffee beans simultaneously. The model of caffeine extraction for hemispherical beans was derived, and the data were curve fitted. Then the results of extraction of caffeine from green beans and roasted beans were discussed. In the second part, the different roasted coffee beans were ground and brewed for experiments. The coffee was dripped in the center of flat disk which was filled with water to a depth of 0.5 cm. The fronts of three different kinds of coffee at different temperatures were plotted as functions of time, respectively. After these data were curve fitted, the Arrhenius plots of diffusivity could be obtained. The relation between diffusivity and viscosity of different coffee samples were compared and discussed.

碩士
國立臺灣大學
事業經營碩士在職學位學程
105
In recent years, the trend of fine coffee blowing from abroad to Taiwan, there have been a lot of boutique coffee shop, coffee makers in Taiwan are also advertised as fine coffee, farmers and stores on the understanding of fine coffee, each has a different interpretation With the argument. Some people think that freshly baked coffee is boutique coffee; some people think that careful handling of "coffee beans into a cup of coffee every step"; some people think that no taste of sugar without cream pure coffee, some people think that electricity to Advertising brand coffee is fine coffee. This paper lists the definitions of the National Coffee Association and is based on the specifications of the Specialty Coffee Association on American as a fine coffee. This paper will be on the competitiveness of coffee beans screening machine as the main axis, the coffee industry in-depth discussion of its competitive advantage, strategy, characteristics and future development. And with the case: coffee beans screening machine, for example, based on industry characteristics, five force analysis, literature, etc., and for business strategy, and SWOT analysis, one by one discussion, combined with the future development trend of Taiwan''s agricultural industry to find its competitive advantage With the appropriate business model of the strategy, methods to get rid of competitors in line with the competitive interests of enterprises to achieve the goal of permanent profit.

碩士
華梵大學
電子工程學系碩士班
107
In recent of years, the drinking population of coffee has increased. People drinking coffee becomes the trend of world, that has driven the marketing and business. Coffee is healthy beverage for human, it is rich in vitamin. During the manufacturing operation of coffee there are three steps, picking green beans, roast, make coffee, and roasted method is the biggest influence on the flavor of coffee. Normally, roasted of coffee is depended by the roaster operate roasting machine adjust firepower, inner pot speed, smoke exhaust. The experienced roaster adjust the flavor of the coffee by recording the coffee heating curve, generally roaster record data by writing, or their experience, so the roasted of coffee is unstable. In this investigation, we install three temperature sensors, a gas pressure sensor, a smoke exhaust wind sensor and a inner pot speed sensor in roasting machine for monitoring the roasted condition of coffee. Additionally, in order to let roaster easier observe roasted condition of coffee, we use Bluetooth module and application technique make roaster efficient and convenient observe any data, by the roasted process of dats, it can support roaster make stable quality of coffee flavor.

碩士
明新科技大學
工業工程與管理系碩士班
103
This study proposes a research structure that the standards of ISO/TS 14067 and the carbon footprint (CFP) guide of Environmental Protection Administration (EPA) are used to investigate the required principles and methods to assess CFP of coffee bean and drip coffee. Based on the relevant standards, the CFPs of coffee bean and drip coffee are gained. A real coffee shop is used as a case study and the most popular coffee type (i.e., Yirgacheffe coffee) in the shop is chosen as target product to assess the CFPs of coffee bean and drip coffee. The system boundary is “cradle to grave”, that is, the CFP quantification shall include the life cycle of the products from raw material acquisition through production, distribution, use, and end-of-life treatment, which could include recycling or disposal. The functional unit is “making a cup of Yirgacheffe coffee”. The results of the study show that the CFPs of coffee bean and drip coffee are 0.10189 Kg CO2e per cup and 0.08717 Kg CO2e per cup, respectively, that is, the CFP of drip coffee is lower than the CFP of coffee bean. Moreover, this study investigates two carbon reduction scenarios. Scenario I is for coffee bean and assumes that consumers use low carbon coffee machines to making coffee. Scenario II is for drip coffee and assumes that the packaging of drip coffee is simplified. The results show that the CFPs of coffee bean and drip coffee are 0.05258 Kg CO2e per cup and 0.06761 Kg CO2e per cup, respectively, that is, reducing 48.40% and 22.44% of greenhouse gases emissions when compared with base scenarios. The results of the study can be used as a reference for carbon reduction during product’s life cycle. Furthermore, the results can provide consumers who care about their environment with information about coffee selection.

碩士
大葉大學
事業經營研究所碩士在職專班
93
In Taiwan, the sales volume of coffee (or coffee bean) has been soaring from 121 metric tons in year 1968 to 11,146 metric tons in year 2003. Coffee (or coffee bean) has become an indispensable part of people’s life and the market has turned into one of the most profitable businesses in Taiwan. Coffee culture simultaneously becomes flourishing. In order to understand the consumers’ behavior and the reason of favoring specific brands, products and services, the framework of this study based on both switching cost of Burnham, Frels, and Mahajan¡ (2003) and service switching behavior of Kenveney(1995), while also examining the concept of service quality of Parasuraman, Zeithaml and Berry (1996, 1985). The research divides consumers into two groups in term of their frequencies of using these products. The goal is set to prove that there are different influential factors regarding the set-up and the maintenance of relationships among different groups. There is a correlation among the frequency of drinking coffee, the characteristic quality of the product and the field of profession. The heavier user will care more about the quality of the product and become more specialized on this field. The frequency of drinking will decide the consumer’s behavior: A heavier drinker will drink coffee more frequently and easier to lock on a very few brands as well as a few flavors. On the other hand, a casual user may drink coffee occasionally with no particular favor to any specific brand or flavor. The frequency of using will also affect the switching behavior. The heavier users will pay attention highly on the service quality. Contrarily, the less frequent ones will be less loyal to a certain brand and hardly think about the switching of the products. The characteristic of product will affect one’s loyalty and the transfer behavior too. The higher the complexity and the discrepancy of a brand are, the less possibility wills a consumer likely switching to the other brand or flavor. Loyalty and the switching behavior have conspicuously correlated to the frequency of use, settings and amount of spending.

碩士
元培醫事科技大學
食品科學系碩士班
105
This study was conducted to assess hygienic quality for coffee and drip coffee bag in Taiwan.One hundred and fifteen coffee vendors were assessed for risk factors of microbial contamination.Microbial analysis using Taiwan food and drug administration (TFDA) methods, chemical analysis using TFDA methods were analyzed by HPLC.The microbial analyses include total aerobic plate count, coliform, Escherichia coli, Salmonella, Staphylococcus aureus and mold. The chemical examine and analyses include the content of ochratoxin A, theophylline, catechins, caffeine.One hundred and fifteen coffee vendors were assessed for risk factors of microbial contamination.The rates of sanitary on total aerobic plate count, coliforms, Escherichia coli, Salmonella, Staphylococcus aureus and mold were all 100%, regarding to the standards of test for food microorganism methods by Taiwan food and drug administration.The amounts of caffeine and catechins were 41.0 - 390.2 mg/300 mL and 4.0 - 100.4 mg/mL, respectively. Ochratoxin A and theophylline were not detected in all samples.Seventy-two coffee vendors were assessed for risk factors of microbial contamination in 2015. The rates of sanitary on total aerobic plate count, coliforms, Escherichia coli, Salmonella, Staphylococcus aureus and mold were 85%, 96%, 100%, 100%, 93% and 100%, respectively. The amounts of caffeine and catechins were 28.6 - 281.2 mg/ 300 mL and 1.0 - 100.6 mg/mL, respectively. Ochratoxin A were not detected in 2016. Twenty drip coffee bag vendors were assessed for risk factors of microbial contamination.The rates of sanitary on mold, caffeine and ochratoxin A were 100%, 37.1 - 78.4 mg/300mL and not detected respectively. This study recommends that the vendorse should abide by the food hygiene standards, good self-management responsibility, reduce the incidence of food poisoning.Because the ochratoxin A test was not detected, so to ochratoxin A toxic test, 7 - 70 days after cultivation, although some of the obvious mold growth, but test ochratoxin A were not detected in all. Another, the antioxidant capbility (total polyphenols content and total flavonoids content) were investigated of coffee bean. With the different solvents (hot water, room temperature methanol and ethanol) and obtain crude extracts from different degree roast (green, 190℃ and heavy baking) of coffe bean, then the content of total polyphenols and total flavonoids were determined. The results shows the coffee bean used 100℃ hot water and 190℃ roasting are full of total polyphenols content.The green coffee bean used 100℃ hot water are full of total flavonoids contents.

碩士
南開科技大學
車輛與機電產業研究所
104
In modern society, it is more and more common for people to drink coffee. Some of people even drink several times a day. The main purpose of this study is to fulfill the coffee lover not just for drinking coffee, but also enablethem to get different kinds of baking result by using different origins of coffee bean and different kinds of baking methods. On the design of this work, due to the widespread use of the Smart Portable devices, people can conveniently control the oven by Apps in smart portable devices. People can realize the actual situation in the oven through information transmitted by smart portal devices rapidly. It transmits and receives the signal by Bluetooth and controls the oven by single-chip core. Through operating system above, we can choose different kinds of coffee beans to bake by preference. Also, we can find out the best baking method depending on characteristic of each kind of coffee beans. In other words, we can have the appropriate baking method for coffee beans in different kinds of originations and typesthrough tests. Besides, we can change the taste of particular coffee beans by baking it as well.

碩士
國立雲林科技大學
電機工程系
103
The thesis developed a coffee roaster using Delta programmable logic controller (PLC). The coffee roaster can program the roast time to get the best results, and provide highly stable and accurate profiling system. We design the human machine interface (HMI) on the Delta PLC. Users can touch the panel to set the parameters of the coffee roaster. The rotary barrel is used to fill coffee beans. The system uses motor control module to control the speed of the rotary barrel through the Delta driver. A combined structural mainframe to program and roast beans at light, city and Italian roasts.

With obesity on the rise, there has been great interest in identifying functional foods that can alter metabolism to mitigate obesity. One nutraceutical that has gained attention is green coffee bean extract (GCBE), sourced from raw coffee beans. Research has shown that it has a variety of biological effects including antioxidant and anti-inflammatory properties and regulation of lipid and glucose metabolism. It has been reported that the main polyphenolic compound in GCBE, chlorogenic acid (CGA), is likely responsible for these effects. However, GCBE had not yet been studied in Drosophila melanogaster, the fruit fly. Drosophila are a noted model organism as flies and humans share 60% of disease related genes and similar mechanisms for metabolic regulation. In this study, flies were treated with 0, 1, or 2 mg/mL GCBE and physiological parameters and gene expression were assessed. GCBE significantly reduced fat accumulation in flies, in part by a reduction in food intake. Flies were also treated with an isoform of CGA, 5-caffeoylquinic acid, but this treatment did not change fat accumulation. Overall, this study serves as a foundation for further research on GCBE to determine its potential mechanism of action. This may inform the use of GCBE as a nutraceutical for the treatment of obesity.

碩士
世新大學
財務金融學研究所(含碩專班)
97
The thesis aims to study how future prices of coffee bean affect the stock price of coffee retailers. I collect the day data of the stock prices of ten coffee relaters in American and four types of future prices of coffee beans from the September of 1989 to the August of 2008 and adapt OLS and GARCH approaches to estimate CAPM model. Empirical results indicate that the firms focusing on either selling coffee or being wholesalers are significantly positively affected by the future prices of coffee beans. In addition , the results show that the coefficients of all coffee relaters is less than 1while Starbucks and McDonald have largers.

碩士
國立中山大學
環境工程研究所
98
Fumes emitted from coffee bean roasters contain various chemicals such as aldehydes, pyridine, volatile fatty acids, and ketones. These chemicals have high odor intensities and are sensitive to human breathing organs and eyes. In Taiwan, most of these fumes are not well controlled before venting to the atmosphere. This research attempted to eliminate these odorous and offensive chemicals by chemical scrubbing methods. Sodium hypochlorite oxidation followed by hydrogen peroxide reduction (hypochlorite-peroxide) was investigated first. After that, ozone oxidation followed by hydrogen peroxide reduction (ozone-peroxide) was also tried. In both methods, hydrogen peroxide acted as a reducing agent for the elimination of either residual chlorine or ozone emitted from the oxidation reaction. Experimental results indicated that both methods were effective. An oxidative scrubbing liquid with an initial effective chlorine content of 200 mg/L and a pH of 12, and an reducing scrubbing liquid with an initial hydrogen peroxide concentration of 1% and a pH of 12 could remove an average of 85% of total hydrogen carbons (THC) in the fume gas from a coffee bean roaster. With a dose of 10 ppm ozone in the fume gas to the oxidative scrubbing liquid (water only) followed by an reducing scrubbing liquid with an initial hydrogen peroxide concentration of 0.3% and a pH of 12, an average removal of 80% of the THC could be removed. An odor intensity (expressed by the dilution to threshold ratio) of 9,772 in the original fume could be reduced to as low as 31 by both methods. As indicated by the data from GC/MS (gas chromatography-mass spectrometry) analysis for the hypochlorite-peroxide method, acrolein, vinyl acetate, 2-butanone, and acetone in the roaster fume could almost completely be eliminated. Traces of chlorinated hydrocarbons as potential secondary pollutants were detected in the treated gases from the hypochlorite-peroxide scrubbing system. While by the ozone-peroxide one, satisfactory results were also obtained with no chlorinated hydrocarbons emitted. An economical analysis shows that the ozone-peroxide approach is a practical one for actual control applications.

碩士
開南大學
商學院碩士在職專班
101
Analysis of Market and Customer Requirements for Coffee Bean in North Taiwan Abstract Coffee has gradually become one of popular drinks along with the societal development and prosperity in Taiwan. Consuming coffee culture becomes part of daily life, especially from few coffee shops before to today's various convenience stores’ handy coffee machines. Taiwan has to import coffee beans due to the increasing demand and the gap from local production. In terms of sales, there are several factors to influence the coffee bean purchase. It’s vital to investigate the purchase factors and people’s preference for coffee bean industry. Therefore, this study is to explore the target market, customer requirement and channel selection while purchasing coffee beans in northern Taiwan. The empirical analysis has concluded four main target markets. The main consideration in the first target market is the flavor and roast skill level. The second target market is the people who are aged from 18 to 30 with monthly coffee expense between NT$ 2,000 to 3,000. The third target market emphasizes quality, age 41 to 50 and spend NT$ 1,000 to 2,000. The fourth target market considers packaging description, age 51 to 60 and spend more than NT$ 4,000. In terms of regional target market analysis, Taipei and other metropolitan areas have the largest demand and request diverse variety. In terms of positioning, the professional roasting skill and marketing attraction of distributors are two key dimensions. In terms of consumers’ channel preference, the café which is adjacent to production field and coffee tourism factory enjoy the advantages of quality, professional level, price and service offering. The department store and composite café enjoy the advantages of atmosphere, convenience and brand awareness. Keyword：Coffee Bean Market, Customer Requirement, Segmentation Targeting Positioning （STP）, Homogeneity Analysis, Multidimensional Scaling Method

碩士
國立中興大學
生物產業機電工程學系所
107
In this study, an auto-sorting system was developed to detect washed green coffee beans with defects. Defects on green coffee beans are caused during the processes of harvesting, drying, hulling, and transporting. Beans with severe defects can be removed using a color-sorting machine. However, the sorting of high-quality coffee beans has to be conducted manually. Therefore, we developed a sorting system with an aim to reduce labor costs. The system performs functions such as auto-feeding, image capturing, color training and classification on a batch of green beans. In this study, image processing techniques were used to extract contour features and color features based on the appearance of green coffee beans. Moreover, a method that detects defects caused to the beans by insects ( insect defect detection method) was developed. Top and bottom images of each bean were captured using cameras. First, 16 shape features were extracted, and coffee beans were classified into chipped defective beans and not chipped beans by using a back-propagation neural network. Second, the insect defect detection method was used to detect holes and very dark spots on beans. Third, color features were extracted from 8-bit gray images and RGB color images. Cluster-color features were extracted by applying K-means clustering on images in the CIELAB color space and by retrieving mean values from the corresponding areas in RGB images. In the offline training mode, clustering color features were used to train a new Bayes classifier for detecting defective coffee beans in various batches of coffee beans. In the online sorting mode, clustering color features were used to estimate the level of partial sourness and partial blackness in beans by using a pretrained Bayes classifier.  The auto-sorting device was tested for seven batches of green coffee beans, and samples were rechecked manually. Based on the sorting results, the weight of defective beans obtained after sorting with the proposed device was on average 79% that of the defective beans obtained through manual sorting. The verified false alarm rate of defective beans was less than 1.6% for the total weight on average.

碩士
國立臺北科技大學
環境工程與管理研究所
106
Coffee is one of the most widely traded commodities in the world – with over 12 billion pounds of coffee produced annually. Coffee production has been a major source of income in Vietnam since the early 20th century till now. Vietnam is the second largest exporter of coffee beans in the world, just after Brazil and also the top producer of Robusta coffee. There are two main methods for the coffee farming methods, that is conventional and organic cultivation. Conventional coffee is among the most heavily chemically treated foods in the world with the "enrichment" of synthetic fertilizers, insecticides, fungicides, and herbicides. Contrary to the conventional method, organic coffee requires no synthetic fertilizers or compound chemicals to be used in the production, which means cleaner of coffee beans, better for air, land, and water quality. The purpose of this research is to identify the hot-spots, estimate and compare the environmental impacts of the Conventional Intensive (CI), Conventional Moderate (CM) and Organic Intensive coffee cultivation. Life cycle assessment (LCA) was used to calculate Carbon Footprint (CF) and compare the environmental impact of coffee production with different input level from Cradle to Gate. The functional unit (FU) is defined as 1 kg of green Robusta coffee bean in Tan Ha Commune, Lam Ha District, Lam Dong Province. In this research the SimaPro software 8.3.0 was used as to compare the environmental impact of coffee cultivations. There are two impact assessment methods were used in this research, first one is IPCC 2013 v 1.03, for 100 years, and ReCiPe v1.13. The results of this study have shown that Conventional intensive contributed the highest impact on the environment, followed by Conventional moderate and Organic intensive. The life cycle assessment (LCIA) results in hotspot assessment for Fertilizer and pesticide application showed that the conventional intensive contributed 85.5% to Global Warming Potential (GWP) due to the high input amount of manure, while conventional moderate contributed 80.4% and organic intensive contributed 68% throughout 30 years of cultivation. Besides, Fertilizers and Pesticides are the powerful influence on Human Health, Ecosystem and Resources (contributed 75% impact totally). CF result for one average productive year shows that the CI (0.935 kgCO2e) method has the highest GWP compared with CM (0.729 kgCO2e and OI (0.644 kgCO2e) because CI have the fertilizer application with the higher amount than two other methods. Based on the results of this study, farmers should prioritize the use of organic compost, from locally available plants or sources to reduce the impact to the environment. Next, farmers can develop local livestock systems to use manure and reduce the long distance of transportation from other areas. The use of manure or compost should control the number of inputs since using a lot of fertilizers (organic and inorganic) does no extra good for the crops. Sustainability is an important requirement to meet consumer expectations and a competitive advantage for Vietnamese agricultural products. Furthermore, it can help Vietnam improve the sustainability of coffee production and lead the way in the international market for a long-term and contribute to reducing global warming.

碩士
亞洲大學
休閒與遊憩管理學系
107
The purpose of this study was to investigate the relationships among service quality and customer satisfaction. The participants were 376 Ou Kewei chain coffee shop customers. The questionnaire was issued. According to the purpose of the research, the results of statistical analysis show that: (1) There are significant differences in service quality and customer satisfaction among consumers of different genders in the chain of coffee shops; (2) Consumers of different ages in the chain of coffee shops There is a significant difference in service quality; (3) There is a positive relationship between service quality and customer satisfaction (r:.63, p < . 0 01); (4) Service quality will positively affect customer satisfaction (R2:. 39, p < . 0 01). According to the results, it is recommended that the marketing department of Ou Kewei chain coffee shop should formulate marketing strategies for all age groups and regularly carry out relevant promotion activities, and at the same time strengthen service quality to enhance customer satisfaction.