Orientador: Telma Teixeira Franco / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-21T16:33:14Z (GMT). No. of bitstreams: 1 Piovani_MonicaRegina_D.pdf: 3018875 bytes, checksum: fd8c35c2204ec9208757e570785a6b90 (MD5) Previous issue date: 2012 / Resumo: As microalgas são microrganismos que vem sendo utilizados na bioconversão de carbono em produtos com interesse comercial como, por exemplo, biocombustíveis, corantes, suplementos alimentares e cosméticos. Elas podem ser cultivadas em sistemas autotróficos e heterotróficas sendo que as fontes de carbono, gasosas ou líquidas, podem ser provenientes de resíduos industriais reduzindo os custos de sua produção. Para identificar quais os possíveis produtos gerados durante o cultivo o objetivo deste trabalho foi avaliar a bioconversão de dióxido de carbono em fotobiorreatores identificando os principais bioprodutos gerados nas fases sólida, líquida e gasosa do sistema. Os experimentos foram conduzidos em fotobiorreatores de coluna de bolhas, alimentados com meio de cultivo sintético, com microalga C. vulgaris em fase exponencial de crescimento. Foi utilizado reator isotérmico, intensidades luminosas de 150?.molm-2.s-1, e injeção de ar com dióxido de carbono na vazão de 1Lmin-1. Além da conversão de carbono foram avaliados métodos de extração de lipídeos baseados no método de Bligh & Dyer e métodos gravimétricos para determinação do teor de umidade. A conversão de CO2 nos sistemas utilizados foi avaliada nas fases sólida, líquida e gasosa e foi expressa em termos de produção de biomassa (6%), em compostos solúveis na fase líquida, e composta orgânicos voláteis (88%) liberados para fase gasosa do sistema. O teor de umidade da biomassa das microalgas foi de 85% para os métodos avaliados e para os métodos para extração de lipídeos foi possível observar a influência do teor de umidade na biomassa na porcentagem de lipídeos que teve variação de 3% a 24% / Abstract: Microalgae are microorganisms that have been used for bioconversion of carbon into products of commercial interest such as, biofuels, pigments, food supplements and cosmetics. They can be grown in autotrophic and heterotrophic systems and the carbon sources, gaseous or liquid, can be derived from industrial wastes, reducing the costs of production. To identify the possible products generated during the culture the objective of this study was to evaluate the bioconversion of carbon dioxide in photobioreactors identifying key byproducts in solid, liquid and gaseous phases the generated in system. The experiments were conducted in bubble column photobioreactors, fed synthetic growth medium, and C. vulgaris cultures in exponential growth phase. The reactor was operated isothermically with 150?molm-2s-1 of light intensities and injection of air with carbon dioxide in the flow 1Lmin-1. Besides the carbon conversion, were evaluated lipid extraction methods based on the Bligh & Dyer's method and gravimetric methods for determination of moisture content. The conversion of CO2 systems will be evaluated in phases solid, liquid and gaseous systems, expressed in terms of biomass (6%), production in soluble compounds in the liquid phase and volatiles organic compounds released into the gaseous phase. The moisture content of microalgae biomass was 85% for the evaluated methods and for the extraction of lipids methods was possible to observe the influence of moisture content in the percentage of lipids that ranged from 3% to 24% / Doutorado / Desenvolvimento de Processos Químicos / Doutora em Engenharia Quimica

Canines have been employed in matters of law enforcement because of their keen sense of smell. Presently, law enforcement officials are utilizing trained canines in routine traffic stops to assess if the vehicle contains any illicit substances. Many believe that this is an infringement on an individual’s fourth amendment rights, which has garnered the attention of both the media and the courts. Many questions have been raised with respect to canines alerting to locations where illicit substances were no longer present. Thus, the purpose of this dissertation research is to evaluate the manner in which active odorants transport and persist onto various substrates. Direct Analysis in Real Time (DART) coupled to an accurate-mass time-of-flight (AccuTOF™) mass spectrometer was used to rapidly analyze the volatile organic compounds (VOC’s) from a variety of narcotic and explosive substances. The DART ion source is a soft ionization technique used in ambient conditions to sample liquids, solids or gases in real time. Thermal desorption of the VOC’s could thus be conducted in seconds. The present study found that the VOC’s from illicit substances transport from one location to another, in a short amount of time, through a process known as advection, which may contribute to canines producing unconfirmed alerts during their training and certifications. Three of the four odorants used in this study produced positive results, with the exception being 2-ethyl-1-hexanol, as it was not detected at any time when held at distances between 0.5 and 3 meters. In addition, the amount of time needed for an active odorant to contaminate an object in its immediate vicinity was explored and the results were determined to be inconclusive. Although they were observed following longer exposure times, it was still deemed to be inconclusive since it was still possible for these odorants to be present, albeit not in detectable amounts, at lower exposure times. Controlled odor mimic permeating systems (COMPS), patented technology by IFRI were tested to determine the possibility of cross-contamination between the training aids, and the results conclude that there was not any evidence of cross-contamination observed during any of the trials.

Doctorat en Sciences / info:eu-repo/semantics/nonPublished

L'analyse de COV spécifiques dans l'haleine (identifié comme biomarqueurs de maladies telles que lecancer) donne une idée de l’activité métabolique et physiologique d'un individu et peut fournir undiagnostic anticipé non-invasif et potentiellement peu coûteux de plusieurs maladies dont le cancer.Mais avant que des tests médicaux ne puissent devenir une réalité clinique, il est nécessaire dedévelopper une technique d’analyse rapide, fiable, économique et portable. Les réseaux de senseurs(nez électroniques) à base de nanomatériaux qui peuvent satisfaire toutes ces exigences, constituentl’élément clef de l'identification des maladies par leur empreinte de COV dans l'haleine. L'objectif decette thèse est de fabriquer différents senseurs chemo-résistifs à base de nanocomposites conducteursayant la capacité de discriminer un ensemble de maladies (comme le cancer du poumon) par l’analysede leur biomarqueur (COV). Par conséquent, afin de fabriquer des senseurs de haute performance avecune grande sensibilité (ppb) et une sélectivité adaptée aux COV ciblés, différentes méthodologiesd’élaboration de nanocomposites conducteur, ont été implémentées. Des fonctionnalisations covalenteset non-covalentes de ces nanomatériaux de carbone ont été réalisées avec différents types demolécules, i.e., oligomères, polymères ou minérales afin d’ajuster la sélectivité et la sensibilité descapteurs. La nanodéconnection des jonctions du réseau percolé formé par les nanocharges de carbone aainsi pu être contrôlée en faisant varier la fonctionnalité chimique de leur surface. Finalement unensemble de senseurs de vapeur chemorésistifs de hautes performances, ayant une sélectivité pour lesbiomarqueurs du cancer du poumon ont pu être fabriqués et intégrés avec succès dans un nezélectronique.The / The analysis of specific VOC in exhaled breath (identified as biomarkers of specific disease like cancer)give an idea of metabolic and physiological activities of an individual and can provide non-invasive andpotentially inexpensive anticipated diagnosis of several diseases including cancer. The invention of afast, reliable, economic and portable technique is highly required before breath testing become a clinicalreality. Nanomaterial based sensor arrays can fulfill all these requirements and can form a solidfoundation for identification of disease related VOC patterns in exhaled breath. The objective of thisthesis was to fabricate different chemo-resistive sensors based on conductive nanocomposites withability to differentiate and discriminate a set of disease (such as lung cancer) biomarker VOC. Thereforein order to fabricate high performance sensors with high sensitivity and required selectivity towardstargeted VOC, adoption of different methodologies for the synthesis of conductive nanocomposite, wasstrongly emphasized.Covalent and noncovalent functionalizations of these carbon nanomaterials with various oligomeric,polymeric or inorganic molecules were done in order to tune the sensor’s selectivity and sensitivity.Nanoswitching at the junctions of percolated network formed by the carbon nanomaterials could becontrolled by varying the organic functionality on the surface.Finally a set of high performance chemoresistive vapour sensors, with different selectivity towardstargeted lung cancer VOC could be fabricated and successfully integrated in an e-nose with highefficiency towards detection and discrimination of a set of disease specific VOC biomarkers.

Cette thèse évolue selon trois axes de recherche. La première partie présente des travaux de spectroscopie TéraHertz (THz) de COV réalisés à l'aide du spectromètre THz par technique de photomélange, ce dernier rendant accessible la région spectrale 0,3-3 THz à haute résolution. Ces travaux concernent l'amélioration de paramètres moléculaires du formaldéhyde (H₂CO) obtenue grâce à la mise en oeuvre d'un système de métrologie performant reposant sur l'utilisation d'un peigne de fréquence. La très haute résolution de ce spectromètre a également permis un travail de collaboration efficace avec différents laboratoires concernant la détermination de coefficients d'élargissement du chlorure de méthyle (CH₃Cl). La deuxième partie montre la possibilité de détection de radicaux légers par technique de photomélange au travers d'études concernant les radicuax hybroxyle (OH) et mercaptan (SH). La très haute résolution de notre spectromètre donne accès à leur structure hyperfine avec des précision encore inégalées dans la région 1-3 THz. Cette partie illustre également l'intérêt de notre collaboration avec la ligne AILES du synchrotron SOLEIL et démontre la grande complémentarité entre le spectromètre photo-mélange et l'interféromètre couplée au rayonnement synchrotron. La dernière partie présente l'initiation au sein du groupe THz d'une étude cinétique effectuée grâce à une chaîne par multiplication de fréquence. Cette étude concerne concerne la photolyse de H₂CO. S'ajoute à ceci une étude visant à caractériser le rayonnement THz en présence d'aérosols de chlorure de sodium hydratés. / This thesis covers three research areas. The first is the THz spectroscopy of VOCs using a THz spectrometer based on photomixing, the latter making it possible access the 0.3-3 THz spectral region with high resolution. This work concerns the improvement of molecular parameters of formaldehyde (H₂CO) obtained through the implementation of metrology system using a frequency comb. The high resolution of spectrometer has also demonstrated its utility effectively together with various laboratories for the determination of broadening-coefficicents of the methyl chloride (CH₃Cl). The second topic shows the detection of small radicals by photomixing through studies of hydroxyl (OH) and mercaptan (SH) radicals. The high resolution of our spectrometer provides access to their hyperfine structure with details unmatched in the 1-3 THz region. This section also illustrates the importance of our partnership with the AILES beamline of the SOLEIL synchrotron and demonstrates the complementary between the photomixing-spectrometer and the interferometer coupled to synchrotron radiation. The last section presents the initiation of a kinetic study in the THz group performed with a frequency multiplication chain. This study concerns the photolysis of the H₂CO. Accompanied by a study to characterize the THz radiation in the presence of sodium chloride aerosols hydrated.

M.Sc. (Chemistry) / Volatile fatty acids (VFAs) play a pivotal in the process of nutrient removal by biological processes particularly the enhanced biological nutrient removal process with a side-stream elutriation process using activated sludge. These acids are said to act as intermediates which provide feed for the organisms in a biological phosphorus and nitrogen removal (BNPR) system, such as phosphorus-accumulating organisms (PAOs) and nitrate-accumulating bacteria (NABs). In wastewater treatment plants, VFAs play a vital role as intermediate organic compounds during the fermentation processes which generate methane gas and when present at elevated levels they are known to cause microbial stress, acidification as well as the poor performance of anaerobic digesters. For these reasons, the routine monitoring of VFA levels in wastewater treatment plants is crucial as they will act as indicators of the efficiency and optimal operation performance of the anaerobic digesters. Normally the VFAs that are commonly produced during the anaerobic fermentation process include acetic acid, propionic acid, butyric acid, and valeric acid and of these, acetic and propionic acids form the major VFAs that are generated, thus the yields of these two compounds provide a useful measure of the anaerobic digester performance. For example, the ratio of propionic acid to acetic acid is always used as an indicator of digester imbalance while high concentrations of acetic acid (e.g. > 800 mg/ℓ) or a propionic acid to acetic acid ratio greater than 1.4 is an indication of digester failure. This study was thus aimed at establishing the complete VFA profile at the Johannesburg Water (JW) Northern Works Wastewater Treatment Plant in Johannesburg, South Africa, by developing analytical methods to quantify the VFAs in the wastewater treatment plant. In addition, the level of VFAs quantified was used to evaluate the efficiency of the fermentation treatment process in wastewater treatment systems in order to give an indication of the bacterial activities in the systems; to determine the ratios of the VFAs, especially the propionic acid to acetic acid ratio, to establish the performance and efficiency of various wastewater treatment plants; and to determine whether there is any imbalance in the anaerobic digesters. Two analytical methods for the determination of VFAs were successfully developed and applied to real wastewater samples. The first method developed was a liquid-liquid extraction method using gas chromatography time-of-flight mass spectrometry (GC-TOF-MS. The method involved two extracting solvents, namely dichloromethane (DCM) and methyl-tert-butyl ether (MTBE). The extraction capacity of these two solvents was compared. The second method successfully developed and optimised headspace-solid phase microextraction (HS-SPME) using GC-TOF-MS. The microextraction fibre used was a polydimethylsiloxane (PDMS) fibre. Studies to validate the developed methods were also carried out by calculating the limit of detection (LOD) and limit of quantification (LOQ). Ratios of propionic acid to acetic acids were determined as well as the concentrations of acetic acid for both developed methods in order to evaluate the performance and efficiency of the treatment process. The results of the study show that the extraction procedure using solvents DCM and MTBE showed that exhaustive extraction was achieved by MTBE. Higher concentrations of acetic acid and propionic acid were obtained by MTBE. The overall fermentation performance for all three units in the period when the samples were collected, which was measured by the ratio of propionic to acetic acid was good since the ratio did not exceed 1.4. The acetic acid concentration in mg/ℓ was < 800 mg/ℓ for all units thus it can be said that the reactor balance was maintained for the period studied. The method LOD ranged from 0.034 mg/ℓ to 0.21 mg/ℓ and the method LOQ ranged from 0.11 mg/ℓ to 0.70 mg/ℓ. Optimisation of extraction parameters was achieved for headspace solid-phase microextraction using the PDMS fibre method. The extraction method was conducted for 60 min using a sample volume of 4 mℓ and the amount of sodium salt added was 1.50 g. The desorption temperature and time was 210ºC and 5 min, respectively. The LOD values ranged from 0.079 to 2.07. The PDMS fibre was found to be suitable for extracting higher carbon chain fatty acids as compared to lower carbon chain fatty acids. The plant performance for the period studied was on par as indicated by ratios of propionic acid to acetic acid which all fell below 1.4. There were no digester failures for the period studied. The acetic acid concentration in mg/ℓ was < 800 mg/ℓ for all 3 units.

If the analyses of trace components in complex organic samples are to be optimised, then these compounds must be isolated either physically or chemically from surrounding matrices. Ion mobility spectrometry (IMS) is an analytical technique used worldwide for the detection of on-site trace compounds. The technique can be optimised to isolate the target species from complex matrices through both physical separation, based on the mobility of the analyte ions at ambient pressure, and chemical discrimination through preferential ionisation of the target. Optimisation of the latter is commonly achieved through doping the spectrometer with a selective reagent gas, termed a dopant. The chemical processes required to optimise the responses of target analytes are dependent on the identity and concentration of the dopant. As such, a variety of dopants have been successfully implemented in ion mobility spectrometers. The technology for the deliverance of dopants in IMS is commonly through permeation sources, which provide a stable chemical environment in the ion mobility cell. Althoughrelatively inexpensive and durable, these devices are difficult to change and generally deliver a single dopant concentration. As a result, only one type of chemistry is possible and the responses cannot be optimised for a range of analytical applications. Such limitationsbecome increasingly significant when IMS is hyphenated to a chromatograph where a range of different dopant conditions may be sought over the course of a chromatographic run. This thesis sought to overcome these limitations through the development and implementation of piezoelectric dispensers, interfaced directly to the transport gas regions of IMS cells. The study demonstrates for the first time the ability to use piezoelectric dispensing as a dopant introduction methodology in IMS for controlling and calibrating a range of dopant chemistries. 2-butanol, acetone, dichloromethane, 1-chlorohexane, 4-heptanone and 1-bromohexane were the candidate dopants chosen for the studies, covering a wide range of physical and chemical properties. The novel technology was used to dispense the target dopants into IMS cells at concentration ranges over three orders of magnitude. Dopant chemistries were achieved within three seconds from the point of dispensing, administered in drop-ondemand formats, and could be delivered either transiently or at steady-state concentrations. The concept was validated through integrated spectral dopant responses. In transient control, dynamic linear relationships of R2 = 0.991 - 0.998 were achieved between dispensed dopant mass and peak area. Under continuous operation, the RSD of the dopant level was < 18% for all dopants. Clear out times for dopant responses were in the order of 3-5 seconds, indicating negligible hysteresis effects. The study also proved the concept of controlling monomer and dimer ion chemistries from 2-butanol actuations when interfaced to a differential mobility spectrometer at mass fluxes between 21 - 1230 ng m-3 , and the simultaneous control of dopants in negative and positive ionisation modes to RSDs <10%. This thesis describes the techniques used to optimise the piezoelectric dispensing of the full dopant range, as well as the full design protocols required to interface to mobility spectrometers. The outcomes from these studies provide a realisation for piezoelectric dispensers as a future mainstream dopant introduction technique for the analysis of complex samples.

The exploitation of illicit substances, such as drugs and explosives, is on the rise. Special attention must therefore be considered to reduce the transportation and storage of these illicit substances by improving the capability of detection, even when hidden from view. Although analytical methods of detection for both drugs and explosives have improved over time, biological detectors, such as canines, are still commonly used. In comparison to humans, these canines have a larger number of olfactory receptors and a greater olfactory epithelium surface area, providing them with a more enhanced olfaction than that of humans. The premise for the detection of illicit drugs and explosives is based on the premise that these substances though hidden, will emit volatile organic compounds (VOCs). These VOCs are not often the parent drug or explosive, they are essentially a chemical associated with the source and provide a reliable indication of the illicit substance. Previous successful research has been conducted on the identification of the active odors present in the headspace of cocaine, methamphetamine, and MDMA but instead for marijuana and heroin there have been minimum success. Thus, in the present research a method using headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS) was optimized to identify the VOCs makeup of heroin and marijuana to further identify the active odor compound(s) responsible for the alert response of biological detectors (canines). A mixture of acetic acid and acetylsalicylic acid was identified as target odor mimic for heroin by certified detector canines, while a mixture of limonene and caryophyllene was recognized as odor mimic for marijuana by conducting ORTs. The training aids developed successfully mimic the scent of the actual illicit substance and can be used to improve the capabilities of both drug and explosive detection canines. Additionally, as growing threat of improvised explosives has created a worldwide concern and emphasized the requirement of a greater spectra of canine training aids that covers the complete range of explosives available, a new approach for the creation of training aids for IEDs have been evaluated. The use of a dynamic collection system have proved to be an option to develop fast and reliable canine training aids for IEDs.

Orientador: Helena Teixeira Godoy / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T18:38:45Z (GMT). No. of bitstreams: 1 Sganzerla_Marla_D.pdf: 11263877 bytes, checksum: 32ac84fea7f4793868e0e58797653653 (MD5) Previous issue date: 2015 / Resumo: As pimentas do gênero Capsicum apresentam ampla aplicação em função dos atributos sensoriais de cor, pungência e aroma, decorrentes da presença de carotenoides, capsaicinoides e voláteis. No entanto, variações no conteúdo desses metabólitos secundários dependem de fatores como sazonalidade, ritmo circadiano, desenvolvimento da planta, características edafo-climáticas, ataque de patógenos. Neste estudo foi realizada a caracterização da composição de capsaicinoides e fração volátil de frutos de Capsicum chinense. A caracterização foi realizada através do uso de métodos analíticos cromatográficos (UPLC, UHPLC-MS e GC-MS). Com a execução desta pesquisa, foi possível caracterizar os frutos de C. chinense quanto à composição de metabólitos relacionados aos seus principais parâmetros de qualidade, fornecendo subsídios científicos para o conhecimento e melhoria da qualidade em termos de produção, aplicação industrial, compreensão de rotas metabólicas e melhoramento genético, além de gerar informações a respeito de substâncias potencialmente benéficas, devido a suas ações no organismo humano. Inicialmente foram desenvolvidos e validados os métodos, usando ferramentas estatísticas. De acordo com a etapa de otimização para a extração dos capsaicinoides, 100% de metanol combinado com o uso do banho de ultrassom por 10 minutos foram empregados. O método analítico desenvolvido através do uso de cromatografia em fase líquida de ultra eficiência permitiu a separação de 8 capsaicinoides em 4 minutos de análise cromatográfica e mostrou-se eficiente de acordo com a validação realizada. 9 acessos de pimentas C. chinense foram analisadas. Os teores de capsaicina e dihidrocapsaicina obtidos estavam nas faixas de 156 - 1442 ?g.g?1 e 26 - 478 ?g.g?1 (peso de fruto fresco), respectivamente. A caracterização do perfil de voláteis em pimentas 'Habanero', através do uso de HS-SPME (Headspace Solid-Phase Microextraction), foi realizada após etapa de otimização. Delineamento composto central e ferramenta de desejabilidade foram usadas a fim de avaliar, simultaneamente, duas respostas: soma total da área dos picos e número de compostos extraídos. O resultado maximizado para as duas respostas usando a fibra tripla (DVB/Car/PDMS) indicou o uso das condições de temperatura de extração de 40 °C e 30 min de extração. 82 compostos foram tentativamente identificados na fração volátil da pimenta 'Habanero' e os ésteres foram os compostos mais abundantes. O 2,3-dimetilciclohexanol e longifoleno foram identificados pela primeira vez em pimentas 'Habanero'. Além disso, pimentas 'Habanero' submetidas à diferentes condições de disponibilidade de água durante seu cultivo foram avaliadas quanto a composição de capsaicinoides e voláteis. Maiores quantidades de capsaicina e dihidrocapsaicina foram encontradas na pimentas maduras, alcançando valores entre as faixas de 2,85 - 3,33 mg.g-1 para capsaicina e 1,06 - 1,71 mg.g-1 para dihidrocapsaicina. Os teores de compostos voláteis totais foram maiores nas pimentas verdes (195,47 - 298,94 mg.kg-1), independente do tratamento de estresse hídrico que receberam. Os resultados obtidos com o PCA realizado possibilitaram, inicialmente, separar as pimentas 'Habanero' em função do grau de maturação. Enquanto, PCA aplicado, separadamente, nas pimentas verdes e maduras demonstrou uma separação evidente em função da data de colheita. Isso se deve ao fato de que influências do grau de maturação e época da colheita se sobressaíram no estudo. As pimentas foram agrupadas de acordo com o tratamento de irrigação recebido, mas para uma melhor compreensão dos efeitos dos tratamentos de estresse hídrico sobre a composição das amostras, seria necessário uma estratégia de estudo com monitoramento mais frequente dos frutos formados além de outras investigações sensoriais, como o uso de olfatometria. / Abstract: The Capsicum peppers are largely used due their sensorial properties as color, pungency and aroma. These characteristics occur by the presence of determinate classes of compounds including carotenoids, capsaicinoids and volatiles. These secondary metabolism derivatives compounds are influenced by two factors: genetics and plant-environment interactions and are susceptible to water availability conditions. This study had a proposal of the characterization of the capsaicinoids and volatile composition of the Capsicum chinense pepper fruits. The analysis were carried out by using of chromatographic methods (UPLC, UHPLC-MS and GC-MS). The results obtained and the characterization of the C. chinense fruits regarding the mainly compounds which influenced in the quality of the peppers provide the scientific subsidies for improvement of general quality, agricultural practices, industrial applications and breeding programs and also, the knowledge about substances potentially beneficial to the human organism. Initially, was developed and validated a fast, efficient and reproducible method to analyze capsaicinoids in Brazilian Capsicum chinense fruits by means the use of an optimization strategy to extracted the capsaicinoids. The extracts were obtained following the condition 100% of methanol and 10 min on ultrasound assisted extraction. The analytical method developed in an ultra high performance liquid chromatographic system coupled to a mass spectrometer permits the separation of 8 capsaicinoids in 4 min of time analysis expending only 2 mL of solvent as mobile phase. The method achieved was fully validated and show the effectiveness and satisfactory performance to answer the analytical needs of this research area. Different accessions of C. chinense fruits were analyzed, the contents of capsaicin and dihydrocapsaicin were in the range of 156 - 1442 ?g.g?1 and 26 - 478 ?g.g?1 of fresh fruit, respectively. Characterization of aroma profile of Capsicum chinense peppers 'Habanero' type, using Headspace Solid-Phase Microextraction (HS-SPME), was performed after an optimization step by GC-MS. Central composite design and Derringer's desirability function strategies were used for this optimization, in order to evaluate simultaneously the 'total sum peak areas' and 'number of extracted compounds' responses. The maximized results for both responses were obtained using PDMS/Car/DVB fiber, temperature of 40 °C and extraction time of 30 min. Eighty-two compounds were tentatively identified in the volatile fraction of the 'Habanero' pepper and the most abundant were hexyl isovalerate, cis-hexenyl isovalerate, hexyl 3-methylbutanoate, 3,3-dimethylcyclohexanol, longifolene, and 2-methyl-1-tetradecene. The compound 2,3-dimethylcyclohexanol and longifolene were reported for the first time in 'Habanero' pepper. In addition, Brazilian 'Habanero' peppers grown under different condition of water availability were evaluated regarding their capsaicinoids and volatiles composition. The higher values of capsaicin and dihydrocapsaicin were found in the mature peppers, achieving ranges from 2.85 - 3.33 mg.g-1 for capsaicin and 1.06 - 1.71 mg.g-1 for dihydrocapsaicin. Total volatile compounds presented higher values for the peppers in green stage of maturity with ranges from 195.47 - 298.94 mg.kg-1, whereas in the mature samples the range was from 68.74 - 118.50 mg.kg-1. According the results obtained with the PCA performed was possible separe the 'Habanero' peppers in function of the degree of maturity. While, PCA apllied, separately, for green and mature peppers showed a clear separation in function of the harvest date. This fact can be justified by the large influence of maturity degree and harvest date on the peppers composition. The peppers were clustered in function of the water availability treatments received, but to better understand the effects of water availability on the peppers composition, another strategy of evaluation, with more frequent monitoring would be interesting, as well as the inclusion of sensorial studies, as the olfactometry technique. / Doutorado / Ciência de Alimentos / Doutora em Ciência de Alimentos

Orientadores: Edson Tomaz, Osvaldir Pereira Taranto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-28T04:21:58Z (GMT). No. of bitstreams: 1 Pinheiro_ClaironLima_D.pdf: 2779888 bytes, checksum: 5fa91f4decd517c966fafa783aa325da (MD5) Previous issue date: 2015 / Resumo: As indústrias de processamento de suco de laranja geram subprodutos como óleos essenciais, d-limoneno e farelo de polpa cítrica. O farelo de polpa cítrica corresponde a 49 kg de cada 100 kg de laranja processada, sendo definido como bagaço dos frutos processados (cascas, sementes, fibras e partes não aproveitadas durante o processamento) após as operações de prensagem, moagem, secagem e peletização. No entanto, durante o processo de secagem do bagaço para produção de farelo de polpa cítrica, há a emissão de compostos orgânicos voláteis (COV), que ocorre devido as cascas do fruto (albedo e flavedo) presentes no bagaço conterem uma quantidade residual de d-limoneno e óleos voláteis que não foram recuperados em etapas anteriores do processo. Assim, ao serem liberados para a atmosfera, esses COV tornam-se uma fonte primária de poluição do ar e causam problemas ambientais relacionados à formação de ozônio troposférico e névoa fotoquímica (ou smog fotoquímico), além de problemas à saúde humana, como: desconforto olfativo devido ao odor cítrico, irritação dos olhos pelo ozônio troposférico e produtos de oxidação dos COV. Dentro deste contexto, estudou-se a emissão de COV durante a exposição de conjuntos de partículas de albedo e flavedo de laranja-pêra a fluxos de ar com velocidade constante em diferentes tempos de exposição e a sete temperaturas, onde os experimentos foram conduzidos em um módulo experimental, no qual se coletou amostras de gás na saída do fluxo de ar e quantificou-se por cromatografia gasosa com detector de ionização por chama (CG-DIC) os seguintes COV selecionados: furfural, 'alfa'-pineno, 'beta'-pineno, 3-careno, p-cimeno e d-limoneno. Os resultados mostraram que: os principais compostos emitidos foram o d-limoneno, 3-careno e ?-pineno a partir do flavedo com tendência ao aumento da emissão com a temperatura e diminuição com o tempo de exposição, além da emissão de compostos não identificados; a emissão de COV ocorreu por processo de arraste por vapor predominando até 160°C e por arraste a vapor seguido de evaporação por efeito do aumento do tempo de exposição e da temperatura do ar de 160 a 250°C e; a contribuição do albedo nas emissões de COV é desprezível comparada à do flavedo / Abstract: The orange juice processing industries generate products such as essential oils, d-limonene and citrus pulp bran. The citrus pulp bran corresponds to 49 kg per 100 kg of orange processing and this is defined as bagasse of processed fruits (peels, seeds, fibers and parts weren¿t used during processing) after pressing, milling, drying and pelletizing operations. However, in the waste drying process for citrus pulp bran production, there are volatile organic compounds (VOCs) emissions. This occurs because the fruit peel in the residue holds a residual amount of d-limonene and volatile oils were not recover in the previous process steps. Thus, these VOCs become a primary source of air pollution and cause environmental problems related to tropospheric ozone formation, photochemical smog and human health problems, such as discomfort olfactory because of the citric odor, eye irritation by tropospheric ozone and VOC oxidation products. In this context, the emission of VOCs during the exposure of albedo and flavedo particles of sweet orange to air flow with constant velocity, seven temperatures and different exposure times. The experiments were performed in a experimental module, in which gas samples collected at air flow exit and the selected VOCs (furfural, 'alfa'-pinene, ß-pinene, 3 -carene, p-cymene and d-limonene) were quantified by gas phase chromatography with flame ionization detector (GC-FID). The results showed: the main compounds emitted was d-limonene, 3-carene and ?-pinene from flavedo and the emission tended to increase with air temperature increase and it decrease whith exposure time increase; unidentified compounds were detected, but they weren¿t quantified; the VOCs emissions occurred by distillation steam process and by this process following by volatilization process due to time exposure and air temperature increase; the VOCs emissions from albedo was negligible compared to flavedo / Doutorado / Engenharia de Processos / Doutor em Engenharia Química