O presente trabalho teve como objetivo estudar o comportamento de três linhagens de leveduras, sendo duas da espécie S. cerevisiae, (Y-904 e CAT) e uma da espécie S. bayanus, (EC) em duas temperaturas de fermentação 20 e 32 °C, usando dois meios, YEPD (meio controle) e caldo de cana-de-açúcar clarificado. As fermentações foram realizadas em câmara de BOD, estático, em frascos de erlenmeyer, com 200 mL de meio e 1 g de fermento seco. A concentração de açúcar foi padronizada para 150,0 g L-1 de ART (açúcares redutores totais) e 15,2 °brix, nos ensaios que se utilizou o caldo de cana como substrato. As fermentações que se utilizou apenas o caldo de cana foram realizadas em balões de cinco litros, em ambas as temperaturas, nas quais as três linhagens de levedura foram avaliadas, através da análise cromatográfica do destilado. Para a obtenção dos destilados foi montado em laboratório um destilador feito totalmente de vidro. Nos ensaios que se utilizou o meio controle e o caldo de cana nas duas temperaturas de fermentação, as leveduras foram avaliadas quanto ao crescimento celular, o açúcar residual e o teor alcoólico. As amostras dos destilados provenientes das fermentações que utilizaram apenas o caldo de cana como mosto, foram avaliadas quanto: ésteres, aldeídos, acidez volátil, álcoois superiores, álcool metílico, furfural, carbamato de etila, acroleína e cobre. As três linhagens ensaiadas apresentaram diferenças estatísticas entre si e entre os meios utilizados. O objetivo não foi a comparação entre as duas temperaturas e sim avaliar o comportamento das linhagens e verificar a possibilidade de se efetuar fermentações a 20 e a 32 °C. Pela análise cromatográfica alguns componentes voláteis como ésteres, aldeídos, acidez volátil, álcoois superiores e álcool metílico, apresentaram diferenças estatísticas, isto é, a formação desses compostos foi influenciada pela temperatura e pelas linhagens utilizadas. O teor de ésteres aumentou com o decréscimo da temperatura para S. bayanus. A acidez volátil aumentou com o acréscimo da temperatura, assim como ocorreu com a formação de álcoois superiores e de álcool metílico que foi mais elevada a 32 °C do que a 20 °C. Enquanto que outros componentes como: furfural, carbamato de etila, acroleína e cobre não apresentaram diferenças em relação a variação da temperatura ou pelas leveduras utilizadas. / The present work had the aim of studying the behavior of three yeast strains, considering two from Saccharomyces cerevisiae species (Y-904 and CAT) and one from Saccharomyces bayanus species (EC), in two fermentation temperatures, 20 and 32 C, utilizing two mediums, YEPD (control medium) and clarified sugarcane juice. The fermentations were carried out in stable BOD chambers, in bottles of Erlenmeyer, with 200 mL of each medium and 1 g of dried yeast. The sugarcane concentration was standardized to 150g/L of ART (total reductor sugar) and to 15,2 °brix in the essay that was used the sugarcane juice as medium. The fermentations that were used only the sugarcane juice were carried out into 5 liters balloons capacity, in both temperatures, where the three yeasts strains were evaluated through chromatography analysis of the distillates. In order to obtain the distillates, it was built a all-glass distillation apparatus. The yeasts were analyzed as the cell growth, the residual sugar and the alcoholic concentration at the essays which were used the control medium and the sugar cane juice in both temperatures. It was evaluated esters, aldehydes, acidity, higher alcohols, methyl alcohol, furfural, acrolein and copper in the distillates samples which came from the fermentations that used only the sugarcane juice as wort. The three yeast strains showed differences between each other and between the mediums. The aim of this study was not to compare the results between the temperatures, but it was to evaluate the behavior of the strains and find out the possibility of making fermentations at 20 and 32°C. The chromatography analysis showed statistical differences from volatile compounds as: esters, aldehydes, acidity, higher alcohols and methyl alcohol. These results show that the formation of these compounds was influenced by temperature and by the yeats strains used. The content of esters increased when temperature decreased for S. bayanus. The acidity increased when the temperature also increased, the same occurred with higher alcohol formation and methyl alcohol formation. The methyl alcohol formation was higher at 32 C than 20 °C. The others compounds as: furfural, ethyl carbamate, acrolein and copper did not show differences related to the temperature variation and the yeasts strains used.

Silagens de milho inoculadas com Lactobacillus buchneri são mais estáveis quando expostos ao ar. No entanto, os benefícios dessa inoculação são dosedependentes e o incremento de ácido acético nas silagens pode culminar em menor consumo de ração. Dessa forma, o objetivo desse trabalho foi avaliar o efeito de doses de inoculação com L. buchneri nas características de silagens de milho e elucidar as implicações do seu fornecimento como volumoso exclusivo para vacas leiteiras. Foram confeccionadas silagens em silos tipo \'bags\', sendo empregados como tratamentos as seguintes doses de inoculação com L. buchneri: 0, 1x105, 5x105 e 1x106 ufc/g de forragem fresca. O perfil fermentativo das silagens foi modificado pela inoculação, havendo redução nos teores de ácido lático e etanol e incremento nos teores de ácido acético, propiônico e 1-Propanol. As contagens de bactérias ácido láticas foram aumentadas pela inoculação, enquanto as de leveduras foram reduzidas, o que contribuiu para a obtenção de silagens mais estáveis em aerobiose. A composição bromatológica das silagens foi semelhante entre os tratamentos e os desdobramentos do fornecimento das silagens inoculadas para vacas leiras foram: tendência de redução no consumo de matéria seca (CMS); modificação no padrão de consumo de alimentos e redução na produção de leite corrigido para 3,5% de gordura. Neste estudo, a alteração no CMS foi correlacionada com os incrementos de ácido acético, ácido propiônico e 1-propanol nas silagens. / The inoculation with Lactobacillus buchneri in corn silage provides high quality and stabler roughages, when it is exposed to air. However, the inoculation benefits are dose-dependents and the increase of acetic acid in silages could start an intake reduction of this feed. The studies, which evaluated intake and animal performance, are rare e doubtful due to the roughage range variety for dairy cows diets. In this way, the objective of this study was to evaluate the dose effect of L. buchneri inoculation on corn silage characteristics and elucidate the implications of its inclusion as exclusive roughage for dairy cows. The silages were stored in bag silos, which the treatments were composed based on the L. buchneri doses: 0; 1x105; 5x105 and 1x106 ufc/g FM of forage. The silages fermentative profiles were modified by inoculation, occurring reduction of latic acid and ethanol levels and increasing in the acetic acid levels. The LABs counting were increased by the inoculation, meanwhile the yeasts counting were reduced, which contributed to obtain a stabler silage in aerobic environment. The silage chemical composition was alike comparing the treatments, and the results of inoculated silages offered to dairy cows were: tendency of a reduction on DM and NDF intakes; modification on feed intake standards, with lower DMI in the morning period with no changes in ingestion times; and reduction on milk yield corrected for fat content, following the daily milk energy secretion reduction. In this study, the change on DMI was correlated with the increase of acetic acid, propionic acid and 1-propanol in silages.

No description available.

O ozônio (O3) é um dos poluentes que representa grande preocupação em termos de qualidade do ar na Região Metropolitana de São Paulo (RMSP). No ano de 2012 foram observados 98 dias de ultrapassagens do padrão horário da qualidade do ar para este poluente na RMSP. A exposição aos poluentes atmosféricos como O3 e outros está associada ao prejuízo da saúde respiratória. O enfoque deste estudo é determinar os principais Compostos Orgânicos Voláteis (COV) precursores de O3 para auxiliar no controle deste poluente. Neste trabalho foram realizadas 78 amostragens durante a semana de hidrocarbonetos no ano de 2006 e 66 amostragens de hidrocarbonetos, 62 de aldeídos e 42 de etanol durante o ano de 2011/2012, 7:00 h às 9:00 h, na estação CETESB IPEN/USP. Medidas de COV também foram realizadas no ano de 2006 e 2008, na Estação CETESB Cerqueira César. Adicionalmente, foram efetuados testes de emissões veiculares durante o ano de 2009 de 5 veículos a diesel, 3 a etanol, 2 a gasolina C e 1 motocicleta. O modelo de trajetórias OZIPR foi utilizado para determinar os principais precursores de O3. Durante o ano de 2011/2012, na Estação CETESB IPEN/USP, a classe de aldeídos representou 35,3% dos COV analisados em concentração na atmosfera, seguido pelo etanol 22,6%, compostos aromáticos 15,7%, alcanos 13,5%, cetonas 6,8%, alcenos 6,0% e alcadienos < 0,1%. Considerando a concentração dos compostos e sua reatividade, as simulações executadas com o modelo OZIPR mostraram que o acetaldeído contribuiu com 61,2% da formação do O3 na atmosfera da RMSP no ano de 2011/2012. Dos COV analisados, a classe dos aldeídos contribui com 74% da produção de O3, aromáticos 14,5%, alcenos 10,2%, alcanos 1,3% e alcadienos (isopreno) 0,03%. O estudo de emissão veicular mostrou que 39% dos aldeídos foram provenientes de veículos a etanol, 28% a diesel, 26% a gasolina C e 7% de motocicletas. As emissões dos COV por veículos a gasolina contribuíram com 44% da formação de O3, a diesel 22%, a etanol 19% e motocicletas 15%. / Ozone (O3) is a pollutant that represents great concern in terms of air quality in the metropolitan area of São Paulo (MASP). In 2012 were observed 98 days of exceedances of the standard time air quality for this pollutant in the MASP. Exposure to air pollutants such as O3 and others is associated with the injury of respiratory health. The focus of this study is to determine the main Volatile Organic Compounds (VOCs) precursors of O3 to auxiliary in control this pollutant. In this work were made 78 samples during the week of hydrocarbons in 2006 and 66 samples of hydrocarbons, 62 of aldehydes and 42 of ethanol during the year 2011/2012, 7:00 am to 9:00 am, at the CETESB IPEN/USP station. Measurements of VOCs also were realized in 2006 and 2008, in the CETESB Cerqueira Cesar station. Additionally, were performed tests vehicle emissions during the year 2009 of 5 diesel vehicles, 3 ethanol, 2 gasool and 1 motorcycle. The OZIPR trajectory model was used to determine the main O3 precursors. During the year 2011/2012, in the CETESB IPEN/USP station the class of aldehydes represented 35.3% of VOCs analyzed in concentration in the atmosphere, followed by ethanol 22.6%, aromatics 15.7%, alkanes 13.5%, ketones 6.8%, alkenes 6.0% and alkadienes <0.1%. Considering the concentration of the compounds and their reactivity, the simulations executed with the model showed that acetaldehyde OZIPR contributed with 61.2% to the formation of O3 in the atmosphere of MASP in the year 2011/2012. VOCs analyzed, the class of aldehydes contributed with 74% of the production of O3, aromatics 14.5%, alkenes 10.2%, alkanes 1.3% and alkadienes (isoprene) 0.03%. The study of vehicular emission showed that 39% of aldehydes were obtained from ethanol vehicles, 28% diesel, 26% gasoline and 7% of motorcycles. Emissions of VOCs by gasoline vehicles contributed with 44% of the formation of O3, diesel 22%, ethanol 19% and motorcycles gasoline 15%.

Espécies de Ficus e suas vespas polinizadoras representam um dos sistemas mutualísticos mais especializados e estudados atualmente, no qual cada representante depende diretamente do outro para sua reprodução. As vespas que recém-emergem de um figo carregam grãos de pólen em seu corpo e são atraídas pelo odor produzido no sicônio (= inflorescência), em fase receptiva, de outro indivíduo. Ao entrar no sicônio através de sua abertura (ostíolo), as vespas não só depositam seus ovos, como também polinizam as flores femininas abertas, iniciando um novo ciclo de vida. Apesar de inúmeros estudos envolvendo questões químicas, filogenéticas, ecológicas, coevolutivas e reprodutivas desse mutualismo, são raros os estudos abrangendo a anatomia do sicônio e as estruturas secretoras presentes nesta inflorescência. Assim, o objetivo deste trabalho consistiu em localizar e caracterizar as estruturas secretoras ativas em sicônios em fase receptiva de nove espécies, representando diferentes linhagens do gênero, esperando-se encontrar as glândulas responsáveis pela produção das fragrâncias atrativas às vespas polinizadoras, e também estruturas que secretam substâncias atuantes na proteção desta inflorescência. Sicônios de Ficus auriculata, F. citrifolia, F. lyrata, F. microcarpa, F. montana, F. obtusiuscula, F. pumila, F. tikoua e F. variegata em fase receptiva foram coletados e processados de acordo com as técnicas usuais para análise em microscopias fotônica e eletrônica de varredura. Grande diversidade de estruturas secretoras foi encontrada nos sicônios das espécies investigadas. Pela primeira vez os sítios produtores de fragrâncias atrativas às vespas foram identificados e consistem em glândulas de odor (osmóforos) de localização distinta: nas brácteas do ostíolo e no receptáculo da inflorescência. Ambos os osmóforos aparentemente atuam na etapa de atração das vespas a longas distâncias; porém o osmóforo presente no receptáculo da inflorescência parece atuar também na quimioestimulação por contato das vespas polinizadoras que pousam no sicônio receptivo, estimulando-as a entrar na inflorescência. Estas glândulas teriam surgido no gênero Ficus, não ocorrendo em linhagens ancestrais na mesma família, corroborando a importância dos voláteis na manutenção do mutualismo figo-vespa de figo. Além das glândulas de odor, os sicônios das espécies de Ficus apresentam outras estruturas secretoras não relacionadas à atração de polinizadores, como laticíferos, idioblastos fenólicos, epiderme fenólica e tricomas secretores de compostos fenólicos, nas brácteas do ostíolo, no receptáculo da inflorescência e em tecidos florais. Estas estruturas devem atuar na proteção do sicônio, estrutura de extrema importância que garante a continuidade dos ciclos de gerações tanto da espécie vegetal quanto de seus polinizadores. A interação com um grande número de fitófagos e o elevado custo da herbivoria para o sucesso reprodutivo da espécie provavelmente foram os fatores que levaram à seleção destas estruturas ao longo da evolução do grupo. / Ficus species and their pollinating wasps represent one of the most specialized and currently studied mutualistic systems, in which each representative directly depends on the other for its reproduction. Wasps that newly emerged from a fig carry pollen on their bodies and are attracted by the scent produced by another plants syconium (= inflorescence), in its receptive phase. Upon entering the syconium through its opening (ostiole), not only the wasps lay their eggs, but also pollinate the open female flowers, starting a new life cycle. Despite numerous studies involving chemical, phylogenetic, ecological, coevolutionary and reproductive issues regarding this fig-fig wasp mutualism, studies comprising syconiums anatomy and secretory structures present in this inflorescence are rare. Therefore the aim of this study was to locate and characterize the active secretory structures in receptive phase of syconia in nine species, representing different lineages of the genus. We intended to find the glands responsible for the production of fragrances that are attractive to pollinating wasps, and also structures that secrete substances acting in syconium protection. Receptive syconia of F. auriculata, F. citrifolia, F. lyrata, F. microcarpa, F. montana, F. obtusiuscula, F. pumila, F. tikoua and F. variegata were collected and processed according to the usual techniques for analyses in photonic and scanning electron microscopies. Great diversity of secretory structures was found in syconia of investigated species. For the first time, the sites producing attractive fragrances were identified and consist of scent glands (osmophores) of distinct location: ostiolar bracts and inflorescence receptacle. Both osmophores apparently act on the attraction of wasps over long distances, but the osmophore of the inflorescence receptacle seems to also act in chemostimulation by contact pollinating wasps land on receptive syconium and are encouraged to enter the inflorescence. These glands would have arisen in the genus Ficus (they do not occur in ancestral lineages in the same family), which confirms the importance of volatiles in the maintenance of fig-fig wasp mutualism. In addition to the scent glands, syconia of Ficus species present other secretory structures that are not associated to the attraction of pollinators: laticifers, phenolic idioblasts, phenolic epidermis and phenolic-secreting trichomes, occurring in ostiolar bracts, inflorescence receptacle and floral tissues. These structures must act in the protection of the syconium, an extremely important structure that ensures the continuity of generations cycles of plant species and their pollinators. The interaction with a large number of phytophagous animals and the high cost of herbivory for the reproductive success of the species were probably the factors that led to the selection of these structures along the evolution of the group.

Viruses can affect plant-insect interactions by altering emission of plant volatile organic compounds (VOCs). Previous work in the lab suggested that VOCs emitted by tomato (Solanum lycopersicum) plants infected with cucumber mosaic virus (CMV) were more attractive to bumblebees (Bombus terrestris) in free choice assays. I extended this work using Arabidopsis thaliana mutants with lesions in genes encoding factors in RNA silencing. In conditioning assays, I confirmed that plant VOC emission is controlled in part by the microRNA regulatory pathway. I used gas chromatography coupled to mass spectrometry and principal component analysis to confirm that CMV infection caused changes in VOC emission by tomato. VOCs collected from non-flowering mock-inoculated and CMV-infected plants were qualitatively distinct from each other. CMV-infected plants also released greater quantities of VOCs than mock-inoculated plants. CMV appears to be both ‘turning up the volume’ of plant volatile emission, whilst ‘tuning’ volatile blend composition so as to diminish levels of a repellant signal. These data are likely to explain how bumblebees can discriminate between VOCs emitted by mock-inoculated and CMV-infected plants. To determine if CMV infection of tomato plants affects plant reproductive success, I carried out a series of bumblebee pollination experiments. Bumblebees pollinate tomato by ‘buzzing’ (sonicating) the flowers, which releases pollen and enhances self-fertilization and seed production as well as pollen export. First, I established that CMV-infected tomato plants produced fruits with a lower seed yield than mock-inoculated plants. When single bumblebees were allowed to buzz-pollinate flowers in a small flying arena, the fruit that developed from buzz-pollinated flowers on virus infected plants had significantly more seeds than fruit from non-visited flowers. Subsequent experiments were performed in a large flying arena. Bumblebees consistently spent longer foraging on the mock-inoculated tomato plants but seed yield was increased by bumblebee pollination in both mock-inoculated as well as virus-infected tomato plants. However, although buzz-pollination significantly enhanced seed yield from CMV-infected plants compared to fruit from non-buzz-pollinated flowers, the yield was higher in buzz-pollinated fruits from mock-inoculated plants. Similar experiments were carried out utilizing a transgenic line of tomato that constitutively expresses the green fluorescent protein in order to estimate the level of cross-pollination from either CMV-infected plants to mock-inoculated plants or vice versa. More pollen from virus-infected plants was transferred to mock-inoculated plants than the reciprocal cross. However, some caution is needed in the interpretation of the larger scale experiments because the tomato plants were affected by a fungal infection. I investigated if the defensive plant hormone salicylic acid (SA) affects bee-perceivable VOC emission. Exogenous SA treatment renders non-flowering tomato plants more attractive to bumblebees in free choice experiments in which bees could only perceive VOCs, but bumblebees spent less time visiting SA-treated flowering tomato plants in the glasshouse (when the bumblebees were allowed unimpeded access to the flowers). Taken together, these data provide evidence that virus infection can affect host-pollinator interactions. Speculatively, CMV infection may change the fitness of susceptible plants via changes in production of pollinator-attractive VOCs and this may affect the balance of resistant or susceptible plants within the host population.

Dans ce travail, une configuration laminaire stratifiée est utilisée afin d’étudier les caractéristiques de la pyrolyse et de l’oxydation du charbon pulvérisé dans un mélange de flux réactif à la fois dans les conditions atmosphériques conventionnelles et dans des conditions de combustion enrichie en oxygène. Deux diagnostics optiques, la spectroscopie d’émission de flamme et la mesure de l’émission spontanée sont utilisés pour caractériser la structure de la flamme. Les profiles de concentration de trois radicaux excités, OH*, CH* and C*2 sont mesurés et analysés.Des simulations 1-D utilisant la cinétique détaillée y compris des sous-mécanismes de OH*, CH* and C*2 et de combustion de charbon sont effectuées et comparées avec des données expérimentales. La comparaison qualitative a montré que la configuration numérique actuelle était appropriée pour la prédiction des émissions de OH*, CH* and C*2. Les résultats prédits par l’approche numérique diffèrent avec les modifications apportées aux sous-modèles de charbon et aux paramètres cinétiques. Le modèle de pyrolyse et les matières volatiles semblent jouer des rôles plus importants. / In the present work, a laboratory-scale laminar strained configuration is used to investigate the characteristics of pulverized coal devolatilization and oxidation in a mixture of CH4/O2/N2 reactive flow both in conventional air conditions and in oxygen-enriched combustion conditions. Two optical diagnostics, Flame Emission Spectroscopy and measurement of spontaneous emission, are employed for the characterization of flame structure. The spatial concentration evolution of three excited radicals, OH*, CH*and C*2 , are measured and analyzed.1-D simulations using detailed gas-phase kinetics including OH*, CH*, and C*2 sub-mechanisms and coal combustion submodels are performed and compared with experimental data. Qualitative comparison with experiments showed that the current numerical configuration was suitable for the prediction of OH*, CH* and C*2 emission. The predicted results differed with changes to the coal sub-models and kinetic parameters. The devolatilization model and volatile matters seem to play more important roles.

La distillation dite « charentaise » est une méthode de distillation discontinue permettant la production d’eaux-de-vie de cognac à partir de vin. La distillation est effectuée dans des alambics en cuivre avec un chauffage à feu nu qui peut être favorable à la génération de composés volatils. Or, les précurseurs et les mécanismes de réactions formant ces composés, pendant la distillation, restent mal connus. La première partie de l’étude consiste à identifier les composés volatils formés au cours de la distillation charentaise. Le bilan matière effectué sur de nombreux composés lors du procédé de distillation a révélé que 2 esters, 3 aldéhydes, 3 terpènes et 12 norisoprénoïdes étaient générés. Par la suite, deux distillations utilisant un mode de chauffe différent (feu nu et vapeur) ont été menées sur un alambic pilote. Le but était d’évaluer l’impact du mode de chauffe sur la génération en composés volatils. L’étude a montré que le mode de chauffe a peu d’effet sur la génération en composés volatils. De plus, les composés formés sont similaires à ceux formés lors de la distillation en alambic traditionnel. Enfin, le troisième axe de l’étude porte sur la caractérisation de l’hydrolyse acide de l’α- terpenyl-O-β-glucopyranoside, précurseur impliqué dans la formation de l’α-terpineol, identifié comme étant généré lors de la distillation charentaise ainsi qu’en alambic pilote. Le suivi de la dégradation dans un réacteur hermétiquement fermé de l’α-terpenyl-O-β-glucopyranoside et dans des conditions représentatives du vin durant la distillation montre l’hydrolyse pour former l’α- terpineol, le trans-terpin et son isomère. Cette étude a révélé que l’hydrolyse du précurseur est favorisée en milieu aqueux et suit une cinétique d’ordre 1 / The « charentaise » distillation is a batch distillation method that allows the production of cognac spirits from wine. The distillation is performed in copper alembics through a direct open flame heating that could favor the formation of volatile compounds. The first part of this study consists in identifying the volatile compounds formed during the distillation of cognac spirits. The mass balance performed on volatile compounds revealed that 2 esters, 3 aldehydes, 3 terpenes and 12 norisoprenoids were generated. Thereafter, two distillations using a different heating mode (direct open flame and steam) were conducted on a small-scale alembic. The goal was to assess the impact of the heating mode on the formation of volatile compounds. The study showed that the mode of heating has little effect on volatile compounds’ generation. Moreover, the compounds formed are similar to the ones during the traditional distillation of cognac spirit. Finally, the third part of the study focuses on the characterization of the acid hydrolysis of α-terpenyl-O-β-glucopyranoside which is the suspected precursor to be involved in the formation of α-terpineol, identified as generated during the charentaise distillation and in small-scale distillations. α-terpenyl-O-β- glucopyranoside was placed in two representative model solutions corresponding to the initial wine and the stillage. Both solutions were exposed to 100 °C in a closed reactor system. Results showed that the hydrolysis of the precurseur formed α- terpineol, trans-terpin and its isomere that seems to be 4-(2-hydroxypropan-2-yl)-1- methylcyclohexan-2-ol). Data also revealed that the hydrolysis of the precursor follows a first order reaction model ant that an aqueous media promotes the formation of trans-terpin.

Cheung Hiu-Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 140-150). / Abstracts in English and Chinese. / ABSTRACT --- p.i / ACKNOWLEDGEMENTS --- p.vi / LIST OF FIGURES --- p.xiii / LIST OF TABLES --- p.xv / Chapter CHAPTER 1 --- LITERATURE REVIEW --- p.1 / Chapter 1.1 --- Introduction --- p.2 / Chapter 1.2 --- Soybeans --- p.3 / Chapter 1.2.1 --- Chemistry and nutritional value of soybeans --- p.3 / Chapter 1.2.2 --- Protein composition of soybeans --- p.4 / Chapter 1.2.3 --- Volatile compounds in soybeans --- p.4 / Chapter 1.3 --- Food fermentation --- p.5 / Chapter 1.4 --- Chaw tofu --- p.6 / Chapter 1.4.1 --- Preparation of tofu --- p.7 / Chapter 1.4.2 --- Preparation of chaw tofu --- p.7 / Chapter 1.4.3 --- Microorganisms involved in fermentation of chaw tofu --- p.8 / Chapter 1.4.4 --- Volatile components in chaw tofu --- p.11 / Chapter 1.4.5 --- Proteolytic activity of chaw tofu --- p.12 / Chapter 1.5 --- Stinky brine broth --- p.13 / Chapter 1.5.1 --- The pH value of stinky brine broth --- p.13 / Chapter 1.5.2 --- The salt percentage of stinky brine broth --- p.14 / Chapter 1.5.3 --- Volatile components of stinky brine broth --- p.14 / Chapter 1.5.4 --- Parameters affecting ammonia production of stinky brine --- p.15 / Chapter 1.6 --- Other fermented soy products --- p.16 / Chapter 1.6.1 --- Microorganisms involved in the fermentation --- p.16 / Chapter 1.6.1.1 --- Fermentation of soybean by bacteria --- p.17 / Chapter 1.6.1.1.1 --- Natto --- p.17 / Chapter 1.6.1.1.2 --- Kinema --- p.18 / Chapter 1.6.1.1.3 --- Soy daddawa --- p.19 / Chapter 1.6.1.1.4 --- Hawaijar --- p.20 / Chapter 1.6.1.1.5 --- Thua nao --- p.21 / Chapter 1.6.1.2 --- Fermentation of soybean by moulds --- p.21 / Chapter 1.6.1.2.1 --- Tempe --- p.21 / Chapter 1.6.1.2.2 --- Sufu --- p.22 / Chapter 1.6.1.2.3 --- Soy sauce --- p.22 / Chapter 1.6.1.2.4 --- Soy paste --- p.23 / Chapter 1.6.2 --- Formation of volatile compounds during Bacillus fermentation --- p.24 / Chapter 1.6.3 --- Biochemical changes during fermentation --- p.21 / Chapter 1.7 --- Methods of flavor analysis --- p.30 / Chapter 1.7.1 --- Headspace Analysis --- p.31 / Chapter 1.7.2 --- Aroma characterization --- p.32 / Chapter CHAPTER 2 --- IDENTIFICATION OF ODOROUS COMPOUNDS IN COMMERCIAL CHAW TOFU BASED ON ODOR ACTIVITY EVALUATION --- p.42 / Chapter 2.1 --- Introduction --- p.43 / Chapter 2.2 --- Materials & Methods --- p.46 / Chapter 2.2.1 --- Experimental samples --- p.46 / Chapter 2.2.2 --- Headspace-Gas Chromatography-Mass Spectrometry (GC-MS) --- p.46 / Chapter 2.2.3 --- Conditions of the Gas Chromatography-Mass Spectrometry (GC-MS) --- p.47 / Chapter 2.2.4 --- Compound identifications --- p.48 / Chapter 2.2.5 --- Quantification of compounds --- p.48 / Chapter 2.2.6 --- Statistical analysis --- p.48 / Chapter 2.2.7 --- Calculation of odor activity value (OAV) --- p.49 / Chapter 2.3 --- Results & Discussion --- p.50 / Chapter 2.3.1 --- Odor activity value (OAV) --- p.51 / Chapter 2.3.2 --- Volatile compounds in fresh samples --- p.51 / Chapter 2.3.2.1 --- Comparison of odorous compounds in fresh samples among different locations --- p.52 / Chapter 2.3.3 --- Volatile compounds in deep-fat fried samples --- p.53 / Chapter 2.3.3.1 --- Comparison of odorous compounds in deep-fat fried samples among different locations --- p.54 / Chapter 2.3.4 --- Comparison between fresh and deep-fat fried samples --- p.55 / Chapter 2.3.5 --- Odorous compounds of chaw tofu based on OAVs --- p.56 / Chapter 2.3.6 --- Possible ways for formation of odorous compounds --- p.58 / Chapter 2.3.6.1 --- Protein degradation --- p.58 / Chapter 2.3.6.2 --- Lipid degradation --- p.59 / Chapter 2.3.7 --- Comparison between volatile compounds in chaw tofu and others fermented soybean products --- p.60 / Chapter 2.4 --- Conclusion --- p.61 / Chapter CHAPTER 3 --- IDENTIFICATION OF ODOROUS COMPOUNDS IN COMMERCIAL CHAW TOFU BASED ON GAS CHROMATOGRAPHY-OLFACTOMETRY --- p.67 / Chapter 3.1 --- Introduction --- p.68 / Chapter 3.2 --- Materials & Methods --- p.71 / Chapter 3.2.1 --- Experimental samples --- p.71 / Chapter 3.2.2 --- Gas Chromatography-Mass Spectrometry-Flame Ionization Detection-Olfactometry (GC-MS-FID-O) --- p.71 / Chapter 3.2.3 --- Conditions of the Gas Chromatography-Mass Spectrometry --- p.72 / Chapter 3.2.4 --- Detection of odor active compounds --- p.73 / Chapter 3.2.5 --- Compound identifications --- p.73 / Chapter 3.3 --- Results & Discussion --- p.74 / Chapter 3.3.1 --- "Fecal, rancid and putrid odor" --- p.74 / Chapter 3.3.2 --- "Cabbages, sulfurous and meaty odor" --- p.76 / Chapter 3.3.3 --- Green odor --- p.77 / Chapter 3.3.4 --- Other odor contributing compounds --- p.77 / Chapter 3.3.5 --- Odor generate during deep-fat frying --- p.78 / Chapter 3.3.6 --- Comparison between GC-O and OAVs --- p.79 / Chapter 3.3.7 --- Comparison between volatile compounds in chaw tofu and others fermented soybean products --- p.80 / Chapter 3.4 --- Conclusion --- p.82 / Chapter CHAPTER 4 --- EVALUATION OF CHAW TOFU MODEL FERMENTATION BROTH --- p.86 / Chapter 4.1 --- Introduction --- p.87 / Chapter 4.2 --- Materials & Methods --- p.90 / Chapter 4.2.1 --- Model fermentation broth preparation --- p.90 / Chapter 4.2.2 --- Tofu sample preparation --- p.91 / Chapter 4.2.3 --- Gas Chromatography-Mass Spectrometry --- p.91 / Chapter 4.2.3.1 --- Conditions of Gas Chromatography-Mass Spectrometry (GC-MS) --- p.92 / Chapter 4.2.3.2 --- Compound identification --- p.93 / Chapter 4.2.3.3 --- Quantification of compounds --- p.93 / Chapter 4.2.4 --- Viable cell counts --- p.93 / Chapter 4.2.5 --- pH value and soluble content --- p.94 / Chapter 4.2.6 --- Proteolytic activity --- p.94 / Chapter 4.2.7 --- Statistical analysis --- p.95 / Chapter 4.3 --- Results & Discussion --- p.96 / Chapter 4.3.1 --- Headspaces analysis --- p.96 / Chapter 4.3.1.1 --- Changes in volatile composition in model fermentation broths --- p.97 / Chapter 4.3.1.2 --- Comparison of volatile compositions between the broths --- p.98 / Chapter 4.3.1.3 --- Comparison of volatile compositions among the three deep-fat fried fermented tofu with different broths --- p.101 / Chapter 4.3.1.4 --- Comparison of volatile compositions of deep fat fried fermented tofu with that of the commercial chaw tofu --- p.102 / Chapter 4.3.2 --- Liquid samples analysis --- p.104 / Chapter 4.3.2.1 --- "Changes in viable cell counts, pH values, protease activities and soluble solid contents within model fermentation broths during fermentation" --- p.106 / Chapter 4.3.2.2 --- Viable cell counts --- p.107 / Chapter 4.3.2.3 --- Soluble solid content --- p.108 / Chapter 4.3.2.4 --- Proteolytic activity --- p.106 / Chapter 4.3.2.5 --- pH value --- p.110 / Chapter 4.4 --- Conclusion --- p.112 / Chapter CHAPTER 5 --- GENERAL CONCLUSION --- p.127 / APPENDIX --- p.130 / IDENTIFICATION OF MICROORGANISMS PRESENTED IN THE MODEL CHAW TOFU FERMENTATION BROTHS BY MICROBIAL IDENTIFICATION SYSTEM (MIDI) --- p.130 / Materials & Methods --- p.130 / Model fermentation broth preparation --- p.130 / Viable cell counts --- p.131 / Microbial Identification System (MIDI) --- p.131 / Results --- p.133 / Suggestion on further investigation --- p.134 / REFERNECES --- p.141

Afin de parvenir à une meilleure compréhension de la dynamique d’ascension et d’éruption des magmas basaltiques, nous avons réalisé des expériences de décompression à haute pression (200–25 MPa) et haute température (1200°C) spécifiquement orientées pour documenter la nucléation des bulles de gaz ; ce processus, qui constitue la première étape du dégazage magmatique, conditionne l’évolution de la phase gazeuse (force motrice des éruptions explosives) dans le conduit volcanique. Quatre principaux ensembles d’expériences ont été menés afin de mieux comprendre le rôle des volatils majeurs (H2O, CO2, S), ainsi que les effets de la vitesse d’ascension et de la présence de cristaux sur la cinétique de vésiculation (nucléation, croissance, coalescence) des bulles dans les magmas basaltiques. L’objectif est de comprendre les mécanismes qui contrôlent les caractéristiques texturales (nombre, taille, forme des bulles) et chimiques (teneur en volatils dissous, composition des gaz) des produits naturels et de les approcher expérimentalement. Dans ce sens, les verres expérimentaux ont été analysés avant et après décompression sur le plan textural (microtomographie par rayons X, MEB) et chimique (FTIR, microsonde électronique). Nos résultats démontrent une forte influence du CO2 sur les processus ainsi que sur le mode (équilibre vs. déséquilibre) de dégazage des magmas basaltiques, en lien avec des différences de solubilité et de diffusivité entre les espèces volatiles. Nos données, obtenues dans des conditions voisines des conditions naturelles, ont des implications volcanologiques pour l’interprétation des textures de bulles et des mesures de gaz en sortie de conduit, ainsi que, plus spécifiquement, pour la dynamique des éruptions paroxysmales au Stromboli. / For a better understanding of the dynamics of ascent and eruption of basaltic magmas, we have performed high pressure (200–25 MPa) and high temperature (1200°C) decompression experiments specifically oriented to document gas bubble nucleation processes. Bubble nucleation occurs first during magma degassing and, so, it is critical to understand bubble nucleation processes to constrain the evolution of the gas phase (which is the driving force of explosive eruptions) in the volcanic conduit. Four main sets of experiments were conducted to better assess the role of the major volatiles (H2O, CO2, S), as well as the effects of ascent rate and crystals, on bubble vesiculation (nucleation, growth, coalescence) kinetics in basaltic magmas. The aim of the study is to understand the mechanisms which control the textural (number, size, shape of bubbles) and the chemical (dissolved volatile concentrations, gas composition) characteristics of natural products, and also to approach them experimentally. In this way, experimental melts, before and after decompression, were analysed texturally (by X-ray microtomography and MEB) and chemically (by FTIR and electron microprobe). Our results demonstrate a strong influence of CO2 on degassing mode (equilibrium vs. disequilibrium) and mechanisms, which are shown to be controlled by differences in solubility and diffusivity between the main volatile species. Finally, our data, obtained under conditions closely approaching natural eruptions, have volcanological implications for the interpretation of bubble textures and gas measurements, as well as, more specifically, for the dynamics of Strombolian paroxysms.