Dissertations / Theses on the topic 'Aroma compounds'
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Isci, Asli. "Recovery Of Strawberry Aroma Compounds By Pervaporation." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605084/index.pdf.
Full textC), composition (different model solutions, strawberry essence), concentration (50, 100, 150 ppm) and permeate pressure (4, 8 mbar) on the recovery of aroma compounds of strawberry by pervaporation in terms of mass flux and selectivity. In addition, it was aimed to optimize the extraction conditions (extraction time, temperature, agitation speed, strawberry matrix) of Solid-phase microextraction (SPME), which is used for the analysis of strawberry aroma compounds. Optimum results for SPME were obtained at 40°
C, 700 rpm for 30 min and no matrix effect was observed. Pervaporation experiments were performed using a hydrophobic membrane, PERVAP 1070 (PDMS). As the feed temperature increased, the mass flux and selectivity increased and the total mass flux followed an Arrhenius type relation. Decreasing downstream pressure increased both total flux and selectivity, while increase in feed concentration led to higher organic fluxes but lower selectivities. In general, PERVAP 1070 showed a higher selectivity towards Methyl butyrate (MTB) than Ethyl butyrate (ETB) and MTB flux was affected negatively by the presence of ETB in the feed solution. Pervaporation experiments were also performed with a strawberry essence and strawberry model solution. The selectivities of MTB and ETB were negatively affected by the presence of other aroma compounds.
CHIARELLI, PERDOMO IGOR. "PRODUCTION OF NATURAL AROMA COMPOUNDS BY BIOCATALYSIS." Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/694810.
Full textEsters play a significant role in the food industry, they are among the most important and versatile components of natural flavours and fragrances in food, drinks and cosmetics Their preparation starting from natural substrates and using bioprocesses (e.g., fermentation or enzymatic reactions) is appealing, since the final product can be labelled and commercialized in EU and USA as natural. Therefore, new biotechnological approaches for obtaining flavours are highly demanded as long as they are efficient and sustainable. Many flavour/fragrance esters can be enzymatically obtained using lipases that catalyse esterification, transesterification or interesterification reactions. In this PhD thesis we studied two systems for production of flavours esters: 1) A straightforward biocatalytic method for the enzymatic preparation of different flavour esters starting from primary alcohols (e.g., isoamyl, n-hexyl, geranyl, cinnamyl, 2-phenethyl, and benzyl alcohols) and naturally available ethyl esters (e.g., formate, acetate, propionate, and butyrate) was developed. The biotransformations are catalysed by an acyltransferase from Mycobacterium smegmatis (MsAcT) and preceded with excellent yields (80-97%) and short reaction times (30-120 minutes), even when high substrate concentrations (up to 0.5 M) were used. This enzymatic strategy represents an efficient alternative to the application of lipases in organic solvents and a significant improvement compared to already known methods in terms of reduced use of organic solvents, paving the way to a sustainable and efficient preparation of natural flavouring agents. 2) Mycelium-bound lipase of dry mycelium of Aspergillus oryzae catalysed direct esterification of alcohols and acetic acid in organic solvent, showing high stability towards substrates and products. Water produced during the esterification did not significantly affect the equilibrium of the reaction, allowing for high conversions. These features were exploited for preparing flavour-active acetate esters (e.g., isoamyl and cinnamyl acetate) in batch and continuous systems. A continuous stirred tank membrane reactor (CST-MR) was developed securing good reactor productivity and high biocatalyst stability. Both production systems are promising, represent two different alternatives and can be further optimized and scaled up for the interests of the industry.
Carey, Michelle. "Interaction of aromas with starch/emulsion systems." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268505.
Full textKirsch, Lara [Verfasser]. "Impact of hot water extraction methods on key aroma compounds in beverages from differently roasted coffees and studies on the influence of single aroma compounds on the overall coffee aroma / Lara Kirsch." München : Verlag Dr. Hut, 2019. http://d-nb.info/1192568257/34.
Full textKirsch, Sarah Lara [Verfasser]. "Impact of hot water extraction methods on key aroma compounds in beverages from differently roasted coffees and studies on the influence of single aroma compounds on the overall coffee aroma / Lara Kirsch." München : Verlag Dr. Hut, 2019. http://nbn-resolving.de/urn:nbn:de:101:1-2019080923381229335275.
Full textEscalona-Buendia, Hector B. "Matrix effects on the volatility of red wine aroma compounds." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248433.
Full textFretz, Claudia Barbara. "Aroma active sulphur compounds and their precursors in petite arvine wine /." Zurich : Swiss Federal Institute of Technology, 2005. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=15932.
Full textBaggenstoss, Jürg. "Coffee roasting and quenching technology - formation and stability of aroma compounds /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17696.
Full textWitrick, Katherine Amy Thompson. "Characterization of aroma and flavor compounds present in lambic (gueuze) beer." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/19203.
Full textPh. D.
Di, Gaspero Mattia. "Proteins in White Wines: Their Interaction With Tannins And Aroma Compounds." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3425855.
Full textLa presenza di proteine nei vini bianchi rappresenta un problema di grande importanza per l’industria del vino, principalmente dovuto alla formazione di torbidità nei vini bianchi in bottiglia. L’instabilità proteica, nonché formazione di torbidità, è associata ad alcune proteine di difesa della pianta che per mezzo della loro intrinseca resistenza e stabilità sopravvivono al processo di vinificazione, passando nel vino dove causano la comparsa dell’indesiderata torbidità e di depositi in bottiglia, la quale non incontra le aspettative del consumatore e viene quindi scartata. La torbidità proteica nei vini bianchi è considerata come un processo a tre stadi, che coinvolge la denaturazione delle proteine seguita dall’aggregazione in particelle colloidali capaci di disperdere la luce visibile e far divenire il vino torbido. Data la complessità e la variabilità della matrice vino, i fattori e meccanismi coinvolti in questo fenomeno sono ancora largamente sconosciuti. Normalmente gli enologi prevengono la formazione di torbidità rimuovendo le proteine attraverso l’uso della bentonite. Tuttavia questo trattamento causa la perdita di vino, ed essendo aspecifico, causa anche la rimozione di alcuni composti aromatici. È stato calcolato che il costo totale derivante dall’uso di bentonite corrispondi a 1 miliardo di dollari l’anno. Pertanto è ancora necessaria della ricerca di base e applicata per risolvere il problema della formazione di torbidità proteica nei vini bianchi. La prima parte di questa tesi tratta il tema dell’impoverimento aromatico causato dal trattamento con bentonite. In particolare questo studio prende ispirazione da un precedente lavoro, il quale suggerisce l’esistenza di un’interazione tra le proteine e i composti aromatici. In questo contesto è stata studiata l’interazione della principale proteina dei vini bianchi, la VVTL1, e alcuni esteri etilici degli acidi grassi, i quali sono importanti aromi fermentativi del vino. Data la difficoltà di determinare a livello molecolare questo tipo d’interazione è stata sfruttata la luce di sincrotrone applicata al dicroismo circolare (SRCD) per studiare l’effetto di alcuni esteri etilici di acidi grassi a media catena sulla struttura secondaria della proteina del vino. In seguito, la ricerca è proseguita con lo studio mirato a comprendere l’esatto ruolo dei tannini nel fenomeno che conduce all’instabilità proteica dei vini bianchi. A questo scopo, sono stati studiati tramite sincrotrone gli effetti di diversi polifenoli (derivati o no dal vino) sulla stabilità della VVTL1. In parallelo la capacità nel tempo dei tannini di reagire con le proteine in bottiglia è stata valutata svolgendo degli studi di diffusione dinamica della luce (DLS) in vino modello. Con l’ausilio della Calorimetria differenziale a scansione (DSC), è stato inoltre studiata, la stabilità termica di due tra le più rappresentative proteine del vino (la VVTL1 e la chitinasi classe IV) in presenza di tannini purificati a tempi diversi di evoluzione da vino imbottigliato. Infine, l’ultima parte della ricerca si focalizza nella possibilità di produrre proteine dell’uva in quantità accettabili in forma pura partendo dalla coltivazione in vitro di tessuti di polpa della bacca. Queste proteine possono essere utilizzate per la caratterizzazione strutturale e funzionale. In particolare, con questa tecnica si rende possibile la marcatura delle proteine facendo crescere i tessuti cellulari d’uva in presenza di N15, il quale consentirebbe, per mezzo di metodi spettroscopici, lo studio in dettaglio della loro struttura e delle loro interazioni.
Sartor, Sabrina de Bona 1982. "Compostos voláteis em vinhos Chardonnay (Vitis vinifera L.) produzidos em diferentes regiões brasileiras." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254322.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O aroma final de um vinho é formando por um grande número de compostos químicos voláteis, presentes em concentrações variáveis e detectáveis pelo sistema olfativo humano. O estudo da fração volátil de vinhos tem sido o objetivo de muitas iniciativas de estudo, sendo que as metodologias de pesquisa de compostos voláteis em vinhos compreendem etapas fundamentais, tais como: a extração dos compostos, a separação das diferentes moléculas por cromatografia gasosa acoplada à um sistema de detecção e posteriormente, a identificação e quantificação dos compostos voláteis. O objetivo deste trabalho foi extrair, identificar e quantificar os compostos voláteis de vinhos Chardonnay produzidos em diferentes regiões brasileiras utilizando microextração em fase sólida no modo de headspace (HS-SPME) e cromatografia gasosa acoplada à espectrometria de massas tandem (GC-MSMS). As amostras foram produzidas nas principais regiões vitícolas brasileiras: Serra Gaúcha e Campanha (Rio Grande do Sul), Serra Catarinense e Região de Altitude (Santa Catarina) e Sul de Minas (Minas Gerais). O método de extração de compostos de aroma foi desenvolvido usando a técnica de HS-SPME e GC-MS/MS e análise multivariada com delineamento composto central rotacional (CCRD) e metodologia de superfície de resposta para obtenção de um ponto ótimo de extração. As condições otimizadas foram temperatura (°C) e tempo (minutos) de extração. A otimização multivariada das condições de extração por HS-SPME permitiu avaliar os efeitos de tempo e temperatura de extração nesta metodologia, permitindo a obtenção de um ponto ótimo de extração, 30°C e 45 minutos, dos representantes das classes dos principais compostos voláteis presentes em vinhos Chardonnay. A análise qualitativa e quantitativa da fração volátil dos vinhos foi realizada usando a técnica de GC-MS/MS. O método foi validado e aplicado para a análise de 31 compostos voláteis nas amostras de vinhos Chardonnay. Destes compostos analisados, 30 foram utilizados para a realização de PCA e HCA visando a diferenciação regional dos vinhos. A Análise de Componentes Principais (PCA) e Análise de Agrupamento Hierárquico (HCA) foram realizadas com os dados obtidos. Os resultados obtidos demonstraram que as amostras produzidas em Minas Gerais e na Serra Gaúcha possuem marcadores olfativos herbáceos e vegetais, enquanto as amostras produzidas na região da Campanha/RS, Serra Catarinense e Região de Altitude/SC possuem marcadores florais e frutados, reforçando o papel da origem geográfica na formação e diferenciação do aroma dos vinhos analisados
Abstract: Wine aroma wine is formed by a large number of volatile chemical compounds, present in variable concentrations and detectable by the human olfactory system.The study of the volatile fraction of wines has been the aim of many research studies and those analytical methods including basic steps, such as: isolation and extraction of matrix, separation and detect by gas chromatography coupled to a detection system and finally, the identification and quantification of the individual components. The aim of this study was to extract, identify and quantify the volatile compounds of brazilian Chardonnay wines, produced in different regions, using solid phase microextraction in headspace mode (HS-SPME) and gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). Samples were produced in the main wine producing regions in Brazil: Serra Gaúcha and Campanha (Rio Grande do Sul state), Santa Catarinense and Região de Altitude (Santa Catarina state) and Sul de Minas (Minas Gerais state). A extraction method of aroma compounds was developed and optimized using HS-SPME and GC-MS/MS and multivariate central composite rotational design (CCRD) with response surface methodology to obtain an optimum extraction condition. The optimized conditions were temperature (°C) and time (minutes) of extraction. Multivariate optimization of extraction conditions for HS- SPME allowed to evaluate the effects of time and temperature of extraction allowing the achievement of the optimum extraction point of compounds representatives of the main classes of volatile compounds in Chardonnay wines. The optimum point observed is at temperature in 30 ° C and time in 45 minutes. A method for qualitative and quantitative analysis of the volatile fraction of wines was carried out using the technique of GC-MS/MS. The method was validated and used for the analysis of 31 volatile compounds in samples of Chardonnay wines. From compounds analyzed, 30 compounds were used to perform PCA and HCA targeting regional differentiation of wines. The Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were performed with the data obtained. The results showed that samples produced in Minas Gerais and Serra Gaúcha shows high concentration of compounds with vegetal and herbaceous notes. Meanwhile, samples of Campanha, Serra Catarinense and Região de Altitude shoes high concentration of compounds with floral and fruity notes. These results reinforce the role of geographical origin in the formation and differentiation of aroma in wines
Doutorado
Ciência de Alimentos
Doutora em Ciência de Alimentos
Molina, Gustavo 1983. "Biotechnological production of aroma compounds by the biotransformation of terpenes = Produção biotecnológica de compostos de aroma por biotransformação de terpenos." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254207.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho de doutorado teve como principal objetivo estudar a produção biotecnológica de compostos de aroma a partir da biotransformação de terpenos, analisando potenciais biocatalisadores, processos bioquímicos diferenciados e a otimização das condições de processo envolvidas na produção destes aromas naturais para possíveis aplicações industriais. Inicialmente, o trabalho prático foi direcionado para uma série de estudos com o fungo Fusarium oxysporum 152B, visando complementar os recentes avanços alcançados pelo grupo de pesquisa na caracterização e otimização da bioconversão de R-(+)-limoneno em ?-terpineol. Desta forma, os resultados foram promissores, demonstrando o grande potencial e versatilidade deste fungo para a área, sendo que este biocatalisador foi capaz de produzir diferentes metabólitos a partir dos substratos S-(?)-limoneno, ?-pineno, ?-terpineno e linalol. Na sequência, o trabalho visou avaliar a bioconversão de S-(?)-limoneno para limoneno-1,2-diol em maiores detalhes. A produção de limoneno-1,2-diol, em condições não otimizadas, chegou a 1,2 g.L-1, sendo que foi detectada a continuação desta via metabólica quando este produto foi posteriormente metabolizado a 1-hidroxi-2- oxolimoneno, sugerindo que o fungo Fusarium oxysporum 152B possui uma via de degradação de limoneno recentemente descoberta. O trabalho prático visou também a otimização da produção de limoneno-1,2-diol por meio de uma estratégia sequencial de experimentos. Com base nas análises estatísticas, a produção deste composto a partir da bioconversão de S-(?)-limoneno pelo fungo Fusarium oxysporum 152B chegou a 3,7 g.L-1, utilizando pH 6,5, 5 g.L-1 de substrato, a 28 oC e 250 rpm de agitação. Além disso, esta foi a primeira descrição da utilização do resíduo agroindustrial conhecido como manipueira, originada ao longo do processamento da mandioca, para a produção de biomassa deste fungo, bem como uma das maiores concentrações de limoneno-1,2-diol reportadas na literatura específica. Além disso, o trabalho conduzido visou realizar uma série de comparações práticas entre a biotransformação de R-(+)-limoneno a ?-terpineol e a bioconversão de S-(?)-limoneno a limoneno-1,2-diol, pela mesma linhagem. Adicionalmente, este foi o primeiro trabalho que analisou as diferenças ultraestruturais causadas no biocatalisador ao longo do processo de bioconversão destes substratos, por meio de microscopia eletrônica de varredura e transmissão. Finalmente, foi estudada a otimização da produção de ?-terpineol, a partir da biotransformação de limoneno, utilizando o biocatalisador reconhecido como Sphingobium sp. Após o trabalho prático e análise estatística dos dados, observou-se que as melhores condições para desenvolvimento deste processo foram pH 7,0, concentração de limoneno de 350 g.L-1, agitação de 200 rpm e 28 oC. Nestas condições, a produção deste álcool monoterpênico chegou a 500 g.L-1, que pode ser considerada como a maior concentração de ?-terpineol já relatada na bibliografia de processos biotecnológicos.
Abstract: This work aimed to study the biotechnological production of aroma compounds from the biotransformation of terpenes, analyzing potential biocatalysts, biochemical processes and optimization of process conditions involved in the production of natural flavors for industrial applications. Initially, the practical work was directed to a series of studies with the fungal strain Fusarium oxysporum 152B, aiming to enhance the knowledge obtained in recent advances achieved by our research group in the characterization and optimization of the biotransformation of R-(+)-limonene into ?-terpineol. Thus, the results were promising, showing the great potential and versatility of this fungus to the specific area, and this biocatalyst was able to produce new metabolites from substrates S-(?)-limonene, ?-pinene, ?-terpinene and linalool. In the sequence, this study aimed at assessing the bioconversion of S-(?)-limonene into limonene-1,2-diol in greater detail. Thus, chapters 3, 4 and 5 were designed to a better characterization of this pathway. The production of this compound under non-optimized conditions, reached 1.2 gL-1, and the continuation of this pathway has been detected when this product was subsequently metabolized to 1-hydroxy-2-oxolimonene, suggesting that the fungus Fusarium oxysporum 152B might have a limonene degradation pathway only recently discovered. The practical work also conducted an extensive optimization of the production of limonene-1,2-diol by means of a sequential strategy. Based on statistical analyzes, the production of this compound from the bioconversion of S-(?)-limonene by the fungus Fusarium oxysporum 152B reached 3.7 gL-1, using pH 6.5, 5 gL-1 of substrate at 28 ° C and 250 rpm agitation. Moreover, this is the first description of the use of agroindustrial residue known as cassava wastewater, for the production of this fungal biomass, as well as one of the highest concentration of biotechnological limonene-1,2-diol reported in the specific literature. In addition, the research conducted aimed to perform a series of comparisons between practical conditions involved in the biotransformation of R-(+)-limonene into ?-terpineol, and the bioconversion of S-(?)-limonene into limonene-1,2-diol, for the same strain. Additionally, this is the first study that reported the ultrastructural differences along the bioconversion process of these substrates by means of scanning and transmission electron microscopy. Finally, this work evaluated the optimization of the production of ?-terpineol from the biotransformation of limonene using the biocatalyst recognized as Sphingobium sp. After the practical work and statistical analysis, it was observed that the best conditions for developing this process were pH 7.0, concentration of limonene 350 g L-1, agitation at 200 rpm and 28 oC. Accordingly, the production of the monoterpe alcohol reached 500 g.L-1, which can be considered as the highest concentration of ?-terpineol already reported in the literature for biotechnological processes.
Doutorado
Ciência de Alimentos
Doutor em Ciência de Alimentos
Zhang, Rong. "Genetic analysis of fruit flavor and aroma volatile compounds in wild strawberry." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670142.
Full textLa fresa representa el cultivo de bayas más consumido en todo el mundo, con una producción de 9,2 millones de toneladas en el año 2017. Los programas de mejora se han centrado en caracteres agronómicos, siendo la calidad del fruto un objetivo principal en los últimos años. El sabor es el factor responsable de la calidad en la fresa, actuando directamente sobre el consumidor. La fresa diploide (Fragaria vesca) es modelo para elfresón, debido a su ciclo de vida perenne, pequeño genoma, corto periodo generacional, un sistema de transformación genética simple y eficiente y abundantes recursos genéticos. El objetivo principal de este trabajo es estudiar la base genética del sabor del fruto en la fresa diploide utilizando una colección de líneas isogénicas (NIL) desarrollada por un cruce entre unparental recurrente F. vesca y un parental donante F. bucharica. En primer lugar, incrementamos la colección NIL desarrollada previamente con 10 nuevas líneas, con una cobertura del 94.8% del genoma del parental donante. Para posicionarlos loci de los caracteres cuantitativos (QTL),se analizaron pH, ácido cítrico y ºBrix enfresas maduras. Se mapeó un QTL estable asociado alincrementodel pH, dos QTL asociados con su disminución, dos QTL asociados con la reducción en ácido cítrico y un QTL relacionado con incremento deºBrix. Debido a la localización en LG5 de QTL asociados a compuestos volátiles, estudiamos su acumulaciónen todas las líneas del LG5. Se identificaron diecisiete compuestos volátiles clave y se maparon cinco QTL. Los QTL asociados al metil2-aminobenzoato y mirtenil acetato se localizan en LG5:20-35cM. El QTL asociado a la disminución de metil butanoato se localizó en LG5:11-20cM. Dos QTL ligados a la variación decompuestos volátiles verdes (CVV) (Z)-3-hexenil acetato y (E)-2-hexenil acetato están en LG5:50-76cM. Los genes candidatos que controlan la acumulación de compuestos volátiles aromáticos en LG5fueron once yse analizósu transcripción en frutas completamente maduras de F. vesca y de las líneas NIL de la región LG5.Se identificaron tres genes en LG5:0-35cM y tres genes en LG5:50-76cM que presentan diferencias significativas en la expresión entre el padre F. vesca y las NIL que albergan alelos de F. bucharica. El gen FvH4_5g29270 que codifica una 3Z-2E-enal isomerasa se seleccionó como gen candidato para CVV en LG5:50-76cM. Para verificar la función del gen FvH4_5g29270, se construyó el vector de sobreexpresión génica y se expresó de forma transitoria en F. vesca y en las NILs que contienen el alelo de FvH4_5g29270 en F. bucharica mediante transfección mediada por agrobacterium. Sin embargo, los resultados del contenido de CVVno fueron los esperados, principalmente debido a la baja eficiencia de transformación. La importancia de apariencia externa enfresa es el color,y se analizó aplicando ocho parámetros de color en tres cosechas distintas en la colección. Se observó el color del fruto anaranjado en algunas NILs y se mapeó en LG5:35-39cM. Se analizaron dieciocho genes candidatos en esta región para determinar el nivel de expresión de la transcripción en frutos maduros en plantas de F. vesca y en las NILs que albergan la introgresión LG5:35-39. El gen FvH4_5g14770 que codifica para una proteína de unión al complejo clorofila A-B dependiente de luz se seleccionó como un buen gen candidato ya que mostró un nivel de transcripción significativamente mayor en las fresas de color anaranjado que en las fresas rojas, y dicho cambio puede estar relacionado con la reducción del contenido de clorofila. Todos estos resultados proporcionaron una base fundamental para la mejora del aroma y la variación del color de la fresa.
Strawberry, belonging to Fragaria genus, Rosaceae family, is the most commonly consumed berry fruit crop worldwide, with a production of around 9.2 million tons during 2017. Although traditionally breeding programs have been focused on improving agronomic traits, fruit quality has become a main goal recently. Fruit flavor is the main factor responsible for the fruit quality that is a direct factor attracting customers. The diploid strawberry (Fragaria vesca) serves as an important model plant for cultivated strawberry and Rosaceae family, due to its perennial life cycle, small genome, short generation time, a simple and efficient genetic transformation system and abundant genetic resources. The main goal of this work was to study the genetic basis of fruit flavor in diploid strawberry using a isogenic lines collection (NIL) developed by a cross between the recurrent parent F. vesca and the donor parent F. bucharica. Firstly, we improved the previously developed NIL collection with 10 new lines added. Finally, this population consists of 49 lines with overlapping introgressions covering 94.8% of background of donor parental line. It is a highly relevant genetic tool for mapping a variety of traits for diploid strawberry. Fruit flavor traits, including pH, citric acid and oBrix of ripe fruits of the collection were statistically analyzed for mapping as quantitative traits loci (QTL). One stable QTL was mapped for increasing pH and two major QTL for decreasing pH. Two major QTL were mapped for decreasing citric acid and one QTL for increasing oBrix. Due to locating many major QTL for aroma volatile compounds in LG5, we deeply studied the aroma compounds in the new lines harboring introgressions in LG5. Seventeen key volatile compounds were identified and five QTL were mapped. The QTL for methyl 2-aminobenzoate and myrtenyl acetate were located in the same region LG5:20-35cM.The QTL for decreasing methyl butanoate content was located in LG5:11-20cM. Two QTL for green volatile compounds (Z)-3-hexenyl acetate and (E)-2-hexenyl acetate were located in LG5:50-76cM. In order to investigate the major genes controlling aroma volatile compounds accumulation, eleven genes were selected as important candidate genes to analyze the transcription level in fully ripe strawberry fruits of F. vesca and NILs harboring F. bucharica alleles. Finally, three genes in LG5:0-35cM and three genes in LG5:50-76cM were verified to present significant differences in expression between the recurrent parent F. vesca and the NILs harboring F. bucharica alleles in these LG5 regions. The gene FvH4_5g29270 encoding a 3Z-2E-enal isomerase was selected as candidate gene for green leaf volatile compounds in LG5:50-76cM. For verifying the function of gene FvH4_5g29270, the gene overexpression vector was constructed and transiently expressed in F. vesca and two NILs with the F. bucharica allele of FvH4_5g29270 via agrobacterium mediated transfection. However, the green volatile compounds content results were unexpected, mainly due to the low transformation efficiency. Attending to the important fruit appearance traits, the fruit color was analyzed with eight color parameters for three harvests. Orange fruit color was observed in some NILs and was mapped in LG5:35-39cM. Eighteen candidate genes in this region were analyzed for transcript expression level in fully ripen fruits from the recurrent parent F. vesca and NILs harboring the introgression containing LG5:35-39. The gene FvH4_5g14770 encoding light-harvesting complex chlorophyll A-B binding protein was selected as a good candidate gene since it showed significantly higher transcript level in orange colored fruits than in red fruits that can be related to chlorophyll content reduction. All these results provided fundamental basis for strawberry aroma and color breeding.
Chevance, Fabienne F. V. "Effect of fat on the release of volatile aroma compounds from frankfurters." Thesis, Queen's University Belfast, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268227.
Full textFriend, Ann Marie. "The interaction of sulphur containing aroma compounds from Allium vegetables with meat protein." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408150.
Full textLiggieri, Silvia. "Optimizing grape cluster exposure to increase desirable aroma compounds and decrease disease severity." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/87535.
Full textMaster of Science in Life Science
Carvalho, Cláudia Yong Dias. "Texturizado de manga. Impacto do processamento na componente do aroma." Master's thesis, ISA, 2014. http://hdl.handle.net/10400.5/6793.
Full textThe aim of this study was the analysis of volatile compounds responsible for the flavour of a texturized mango product, namely terpenes, lactones, aldehydes and alcohols, evaluating the impact of the processing applied: thermal treatment to inactivate enzymes, texturization with gellan gum, application of an edible coating and two conservation processes. The analytical method used was gas chromatography combined with the technique of solid phase microextraction. The product under development consists in a bar of mango puree texturized using the hydrocolloid gellan gum, matching 1% of the weight of the mango puree. This percentage is composed by gellan low and high acyl, with the ratio 25/75, respectively. The product also has an edible coating, comprised by 1% of gellan gum which is formed with a 90/10 low acyl/high acyl ratio. The thermal treatment to inactivate enzymes of mango puree caused a decrease of most volatile compounds. The texturized mango puree has exhibited an ability to release the volatiles, similar to mango puree. The edible coating applied to the surface of the texturized product showed retention capacity for a small number of volatiles. The applied conservation processes, high hydrostatic pressures and thermal treatments, showed similar effects and didn’t change the volatile profile of the bar significantly. Microbiologically the product proved to be stable and both conservation treatments applied were effective in microbiological control.
Pimentel, Mariana Recco 1984. "Produção de compostos de aroma a partir da biotransformação de monoterpenos por pseudomonas = Production of aroma compounds through biotransformation of monoterpenes by pseudomonas." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256734.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: O aroma é responsável por grande parte do sabor de um alimento, e considerado um dos atributos mais importantes na aceitação do produto pelo consumidor. A preferência dos consumidores por produtos naturais tem incentivado o desenvolvimento de novos processos biotecnológicos para a produção de compostos de aroma naturais. A biotransformação de terpenos é uma alternativa promissora para a produção de aromas, visto que pode contornar alguns problemas associados a síntese química como a baixa geração de resíduos tóxicos e alta regio- e estéreo-seletividade das reações. Ademais, segundo a legislação brasileira, produtos obtidos por métodos microbiológicos podem ser rotulados como 'naturais' (ANVISA, Resolução nº 104, de 14 de maio de 1999). Os processos de biotransformação de monoterpenos frequentemente utilizam bactérias do gênero Pseudomonas como biocatalisadores por se adaptarem facilmente a diferentes substratos e condições extremas devido a sua elevada versatilidade metabólica e sistema enzimático complexo. Assim, o presente trabalho visou a utilização de monoterpenos (limoneno, a-pineno e citronelol) como substratos em processos de biotransformação por micro-organismos do gênero Pseudomonas. O Capítulo 1 apresenta um artigo de revisão atualizado sobre o potencial biotecnológico de micro-organismos do gênero Pseudomonas como biocatalisadores em processos de biotransformação. O Capítulo 2 refere-se aos resultados obtidos pelos experimentos que contemplam o isolamento de bactérias em meio seletivo e diferencial para Pseudomonas, e sua aplicação em processos de biotransformação de monoterpenos (R-(+)-limoneno, a-pineno, citronelol). Das 34 linhagens selecionadas, 9 bactérias foram capazes de biotransformar pelo menos um dos substratos em compostos de aroma de maior valor agregado. R-(+)-limoneno foi convertido a cis- e trans-carveol e carvona por 7 linhagens, atingindo concentrações de até 412 mg/L, 275 mg/L e 209 mg/L, respectivamente. a-Pineno, por sua vez, foi usado como fonte de carbono e energia por 7 linhagens e foi convertido principalmente em cis-verbenol e verbenona a baixas concentrações por 5 linhagens. Outros compostos como limoneno, mirtenol e ß-pineno, também foram identificados como produtos principais da conversão do a-pineno por 2 linhagens. Por outro lado, apenas 3 linhagens foram capazes de metabolizar citronelol em outros compostos derivados, como óxidos de rosa e isopulegol. O efeito da variação do pH do meio de biotransformação e da indução das linhagens, através da pré-exposição do micro-organismo ao substrato, no crescimento celular e formação de produtos de bioconversão foram avaliados com o intuito de otimizar o processo de biotransformação. A produção de óxido de rosa a partir de citronelol foi estudada e detalhada no capítulo final, que configurou um artigo publicado na revista Chemical Engineering Transactions. Em testes de citotoxicidade, a linhagem mostrou alta resistência a maiores concentrações de terpeno, revelando grande potencial para posterior otimização do processo. Os compostos derivados mais notáveis foram destacados no presente trabalho pela alta qualidade sensorial e alto valor agregado. Além das notas sensoriais altamente relevantes industrialmente, a carvona e o carveol são ainda reconhecidos por apresentar algumas funções biológicas. A verbenona e verbenol se destacam pelo alto custo e vasta aplicação nas áreas alimentícia, da agricultura, e da medicina. O óxido de rosa é um dos componentes mais importantes na criação de composições florais em perfumaria, além de possuir um baixo threshold. Sendo assim, a biotransformação de precursores de baixo custo em compostos de alto valor agregado pode ser considerado uma estratégia vantajosa e econômica
Abstract: Aroma compounds influence greatly the flavor of food products and govern their acceptance by consumers and market success. The increasing consumer preference for natural products has encouraged remarkable efforts towards the development of biotechnological processes for the production of natural flavor compounds. Biotransformation of terpenes represents a very promising alternative for production of aromas, since overcome the problems associated with chemical synthesis such as the low generation of toxic waste and high regio-and stereo-selectivity reactions. In addition, products obtained by microbiological methods can be labeled 'natural' under Brazilian law (ANVISA Resolution No. 104 dated May 14, 1999). Studies on monoterpene bioconversion frequently use bacteria from the genus Pseudomonas as biocatalysts since they adapt easily to different substracts and extreme conditions thanks to their high metabolic versatility and complex enzyme system. Therefore, the present work aims to use monoterpenes, such as limonene, a-pinene and citronellol, as substrate for the biotransformation processes by microorganisms from the genus Pseudomonas. The Chapter 1 presents a current review on the biotechnological potencial of microorganisms from the genus Pseudomonas. Chapter 2 refers to the results obtained from laboratory experiments which include the isolation of bacteria in selective and differential medium for Pseudomonas and their application in monoterpene biotransformation processes ((R-(+)-limonene, a-pinene, citronellol). Among 32 selected strains for investigation of biotransformation capability, 9 bacteria were able to biotransform one of the substrates on value-added flavor compounds. R-(+)-limonene was converted to cis- and trans-carveol and carvone by 7 strains, at concentrations of 412 mg/L, 275 mg/L e 209 mg/L, respectively. a-Pinene, in turn, was used as sole carbon and energy source for 7 strains, and yielded especially cis-verbenol and verbenone at low concentrations by 5 strains. Other compounds such as limonene, myrtenol and ß-pinene have also been identified as major products from the conversion of a-pinene by 2 strains. On the other hand, only 3 strains were able to metabolize citronelol on other derivative compounds, such as rose oxides and isopulegol. The effects of different pHof biotransformation medium and induction phase on cell growth and product concentration were evaluated in order to optimize the biotransformation process. The production of rose oxides by strain L1B2P was studied and detailed separately in the third chapter, set as a published article at Chemical Engineering Transactions. In citotoxicity tests, the strain showed impressive terpene resistance, revealing great potential for further process optimization. Most notable compound derivatives were highlighted in the present work due to their high sensory quality and added value. Besides highly industrially relevant sensory notes, carvone and carveol are also recognized by pursuing some biological functions. The verbenone and verbenol stand by the high cost and wide application in food, agriculture, and medicine fields. Rose oxide, in turn, is one of the most important components in creating floral compositions in perfumery, besides its low threshold. Thus, biotransformation of inexpensive precursors into high value added compounds can be considered an economical and advantageous strategy
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos
Paulino, Bruno Nicolau 1989. "Otimização de processos biotecnológicos para a produção de compostos de aroma a partir de substratos monoterpênicos = Optimization of biotechnological processes for the production of aroma compounds from monoterpenic substrates." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254209.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A crescente demanda por processos que tenham impacto ambiental reduzido, rendimentos consideráveis e ainda custos minimizados recorrem à biotecnologia como uma ciência que pode tornar essa necessidade uma realidade. Processos biotecnológicos para a produção de compostos de interesse industrial como biocorantes, açúcares funcionais, biosurfactantes e biodiesel são uma tendência no meio científico e ganham destaque pela inovação, resultados e aplicações obtidos. O apelo comercial dos produtos biotecnológicos é outro fator que influencia as pesquisas haja vista que esses produtos são considerados naturais e tem-se comprovado que muitos deles apresentam atividades biológicas relevantes. O aroma é um importante atributo dos alimentos e pode ser produzido via biotecnológica a partir de substratos de baixo custo. A utilização de resíduos agro-industriais com alto teor nesses substratos, como por exemplo, resíduos ricos em monoterpenos são de grande interesse na biotecnologia de produção de aromas. Além disso, a utilização de micro-organismos isolados de diferentes fontes como biocatalisadores na produção desses compostos é outra perspectiva, muito explorada e ainda desafiadora. A biotransformação de monoterpenos para a produção de compostos de aroma é vantajosa quando comparada com a síntese química clássica. Contudo, alguns problemas ainda devem ser minimizados, como sensibilidade dos biocatalisadores à toxicidade dos substratos ou condições operacionais e baixos rendimentos. Assim, a seleção de novos biocatalisadores, como micro-organismos endofíticos, o uso de ferramentas de engenharia genética e a utilização de métodos estatísticos de otimização de processos são promissores e caracterizam-se como a nova vertente na área de bioaromas, contornando as desvantagens até então limitantes dos processos de biotransformação. Eles permitem em alguns casos, o aumento de escala e dessa forma a real aplicação da bioconversão microbiana na indústria. Assim, trabalhos que visem selecionar novos biocatalisadores é ainda uma necessidade e quando aliados a otimização de processos podem fornecer caminhos para que os rendimentos da bioconversão de monoterpenos sejam aumentados. Nesse contexto, o presente trabalho visou selecionar micro-organismos com potencial para a bioconversão de monoterpenos de baixo custo e presentes em grandes quantidades em resíduos agro-industriais, como 'alfa'-pineno e R-(+)-limoneno, para a produção de compostos de aroma valorizados comercialmente, S-(-)-verbenona e 'alfa'-terpineol. O capítulo 1 traz uma revisão sobre os compostos monoterpênicos, abordando suas características químico-estruturais, biossíntese e recentes aplicações terapêuticas, além do seu uso como substratos na biotecnologia de produção de compostos de aroma. O capítulo 2 é dividido em duas partes: a parte I mostra os resultados de um screening realizado com 81 linhagens de fungos isolados de diferentes fontes, entre eles, fungos endofíticos, utilizados no estudo do potencial de biotransformação de R-(+)-limoneno e 'alfa'-pineno. A parte II descreve a otimização do processo de produção de S-(-)-verbenona biotecnológica a partir de ?-pineno por uma linhagem de fungo endofítico, ainda não identificado, isolado da romã (Punica granatum). O uso de um Delineamento Composto Central Rotacional (DCCR) de 4 variáveis proporcionou o estabelecimento de condições mais favoráveis ao processo, elevando a concentração de verbenona que era de 66 mg.L-1 para aproximadamente 108 mg.L-1 em um dos ensaios do DCCR e em torno de 98 mg.L-1 no ensaio de validação. O capítulo 3 aborda a otimização do processo biotecnológico de produção de ?-terpineol a partir de R-(+)-limoneno pela linhagem Bacillus tequilensis isolada de resíduos de processamento de frutas cítricas. Após a otimização e validação do processo nas condições consideradas ótimas através da análise de superfícies de resposta, a concentração de ?-terpineol passou de 25 mg.L-1 para 85 mg.L-1. Portanto, os resultados obtidos no trabalho mostraram um ganho de rendimento nos processos de bioconversão de substratos monoterpênicos e que a otimização de processos é uma importante ferramenta para a melhoria das condições experimentais possibilitando trabalhos futuros que envolvam aumento de escala
Abstract: The growing demand for processes that reduce environmental impacts, have high yields and costs minimized uses biotechnology as a science that can make this need into a reality. Biotechnological processes for the production of industrial interesting compounds, such as biocolorant, functional sugars, biosurfactants and biodiesel, are a trend in the scientific field and are highlighted by innovation, application and results obtained. The commercial appeal of biotechnological products is another factor that stimulates researches since these products are considered natural and has been proven that many of them presents significant biological activities. The flavor is an important attribute of food and can be produced through biotechnological processes from low-cost-substrates. The use of agro-industrial wastes with high content of these substrates, such as residues rich in monoterpenes, is of great interest in biotechnology. Furthermore, the use of micro-organisms isolated from several sources as biocatalysts in the production of flavor compounds is another well-explored and challenging perspective. The biotransformation of terpenes for aroma compounds production is advantageous when compared with chemical synthesis. However, there are still some problems that must be minimized like biocatalysts sensitivity, toxicity of substrates and low yields. Thus, the selection of new biocatalysts, such as endophytic micro-organisms, use of genetic engineering and statistical methods for optimization of processes are promising and characterize a new perspective in bioaromas field. Thereby, works that search for new biocatalysts are necessary and associated with optimization processes can improve the monoterpenes bioconvertion. In this context, the objective of this work was the screening and selection of micro-organisms that are able to realize the biotransformation of low cost monoterpenes, 'alfa'-pinene and limonene, into high-value aroma compounds, such as verbenone and 'alfa-terpineol. The chapter 1 presents a current review on monoterpenes, showing their chemical characteristics, biosynthesis and recent therapeutic applications, besides their potential use as substrates for bioflavor production. The chapter 2 is divides in two parts: the first one shows the results of the screening of 81 strains of fungi isolated from several sources, including endophytic strains, for biotransformation of limonene and ?-pinene. The second part describes the optimization process for biotechnological verbenone production from "alfa'-pinene by a non-indentified fungal strain, isolated from pomegranate (Punica granatum). The use of a central composite rotatable design (CCRD) of 4 variables provided the optimal conditions for this process, increasing the verbenone concentration from 66 mg.L-1 to 108 mg.L-1 in one of the CCRD assays and 98 mg.L-1 after validation. The chapter 3 also shows an optimization study, in this case using limonene as substrate and the product obtained was ?-terpineol. The biocatalyst used was a bacterial strain, identified as Bacillus tequilensis, isolated from citrus fruit processing waste. After the optimization and validation in the best conditions obtained through the surface response analysis, the concentration of ?-terpineol reached was 85 mg.L-1. Therefore, the results obtained in this work show an improve of the yields in the biotransformation of both monoterpenic substrates and that optimization of processes is an important tool for the progress of future works involving scale-up studies
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos
Sutherland, Michelle M. "The effect of castration and slaughter age on the aroma of cooked lamb." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320108.
Full textJouanneau, Sara. "Survey of aroma compounds in Marlborough sauvignon blanc wines: regionality and small scale winemaking." Thesis, University of Auckland, 2011. http://hdl.handle.net/2292/7960.
Full textFarmer, Linda J. "Effect of lipid on the formation of volatile aroma compounds by the Maillard reaction." Thesis, University of Bristol, 1990. http://hdl.handle.net/1983/ec5610b1-6425-4d0a-bebb-c24e8393028a.
Full textAbrahão, Meissa Rocha Essenfelder 1984. "Desenvolvimento de processo biotecnológico para produção de compostos de aroma por fungos endofíticos : Biotechnological process development for the production of aroma compounds through endophytic fungi." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254210.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A biotecnologia é uma área interdisciplinar que tem possibilitado inúmeros avanços no desenvolvimento de processos sustentáveis e na obtenção de novos produtos de interesse industrial. Entre estes exemplos estão os aromas naturais que, atualmente, são preferidos por muitos consumidores e já dominam o mercado em certas regiões como a Europa. Uma das opções biotecnológicas para a obtenção destes compostos ocorre pela biotransformação de terpenos, que são derivados de isoprenos, e substratos amplamente distribuídos na natureza. Estes compostos são classe relevante dentre os compostos de aroma e alguns podem ser obtidos a custos relativamente baixos. Limoneno e ?-pineno, por exemplo, estão disponíveis como subprodutos de indústrias de frutas cítricas e de papel, respectivamente. Estes monoterpenos são considerados substratos ideais para obtenção de derivados oxigenados, os terpenóides, muitos dos quais de grande interesse comercial. Nessa perspectiva, 51 fungos endofíticos das frutas caju (Anacardium occidentale L.), jenipapo (Genipa americana L.), sapoti (Manilkara zapota L.) e camu-camu (Myrciaria dubia), foram isolados durante este trabalho. As linhagens foram também avaliadas quanto ao potencial para biotransformação de limoneno ou ?-pineno como fontes únicas de carbono. A partir deste segundo substrato, destacaram-se dois fungos produtores de verbenona, um dos compostos chave do aroma de alecrim (Rosmarinus officinalis). A produção de verbenona por via biotecnológica mostrou um grande potencial para a continuidade dos estudos, tendo em vista que a concentração obtida foi de, aproximadamente, 200 mg/L após 288 horas de contato com o subtrato ?-pineno. Além disso, outro fungo apresentou produção de álcool perílico a partir da biotransformação de limoneno. Este produto é um terpenóide, cujos mecanismos de proteção contra o câncer já tem sido investigados e reconhecidos, aumentando o interesse na sua pesquisa e produção biotecnológica. No encerramento do trabalho, os três fungos com resultados positivos pra biotransformação de terpenos foram analisados em microscopia óptica para observação de suas morfologias e auxílio na identificação
Abstract: As an interdisciplinary field, biotechnology has allowed several advances for the development of sustainable processes and many achievements concerning production of new compounds with industrial interest. Natural aroma compounds have been frequently prioritized by costumers and dominate a considerable market share in some regions such as Europe, and one of biotechnological routes for obtaining these compounds occurs through the biotransformation of terpenes. These substrates are naturally available compounds derived from isoprene units, and represent a relevant class of aroma compounds, which can be often obtained at relatively low costs. Limonene and ?-pinene, for instance, are available as by-products in citrus and pine industries, respectively. These monoterpenes represent ideal precursors for biotechnological production, leading to their oxygenated derivatives denominated terpenoids, some of which commercially valuable. In this perspective, fifty one endophytic fungi from Brazilian fruits, such as cashew (Anacardium occidentale L.), genipap (Genipa americana L.), sapodilla (Manilkara zapota L.) and camu-camu (Myrciaria dubia) were screened during this work. Furthermore, these fungal strains were tested in the biotransformation of limonene or ?-pinene as sole carbon source. Amongst all fungi, two strains showed noteworthy capability to biotransform ?-pinene into verbenone, key compound of rosemary (Rosmarinus officinalis) aroma. The biotechnological production of verbenone proved to be an interesting strategy with a great future potential, considering that that the concentration of this product reached approximately 200 mg/L after 288 hours of contact with the substrate ?-pinene. Moreover, from the biotransformation of limonene, one fungi produced perillyl alcohol. This important terpenoid presents protection mechanisms against cancer already investigated and recognized. The practical steps achieved in this project also involved the observation of these strains with positive results through optical microscopy, in order to verify their morphology and general characteristics
Mestrado
Ciência de Alimentos
Mestra em Ciência de Alimentos
Abdulmalik, Takiyah. "Use of plant-derived essential oil compounds and naturally-occurring apple flavor compounds to control foodborne pathogens in apple juice." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77367.
Full textPh. D.
Millard, Lindsay Theresa. "Effect of Training Systems on Viognier (Vitis vinifera L.) Grape and Wine Glycosides and Volatile Compounds." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/41636.
Full textMaster of Science
Cronje, Joan Christel. "Chemical characterisation of the aroma of honeybush (Cyclopia) species." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5157.
Full textENGLISH ABSTRACT: Honeybush tea, also known as “South Africa’s sweetest tea”, is a herbal tea made from the leaves and twigs of Cyclopia spp., indigenous to the fynbos biome in the Western and Eastern Cape provinces of South Africa. The pleasant sweet aroma and taste of fermented honeybush, its low tannin content and the absence of caffeine have led to widespread interest in the commercial cultivation and processing of honeybush tea since the mid-1990s. Although more than 20 species of honeybush grow in the wild, only a few species are commercially exploited for the manufacture of tea. Currently the more prominent species are C. intermedia, C. subternata, C. genistoides, and C. sessiliflora. The present research contributes to a comprehensive honeybush research programme being conducted at the Agricultural Research Council (ARC) Infruitec-Nietvoorbij in South Africa. The first phase of the present study, using C. genistoides as representative species, was aimed at developing the necessary methodology for the analysis of extremely low concentrations of honeybush volatiles. A high-capacity headspace sample enrichment probe was applied successfully in conjunction with gas chromatography-mass spectrometry (GC-MS) to analyse the volatile organic compounds present in dry or infused unfermented and fermented honeybush. A total number of 255 volatile compounds were identified in unfermented and fermented honeybush, the majority of which are terpenoids (138; 54%) comprising mostly terpenes, terpene ketones, terpene alcohols and terpene ethers. Of the other compound classes, the aldehydes are the largest group, followed by esters, hydrocarbons and ketones. The stereochemistry of the identified compounds was determined whenever possible. This is the most comprehensive chemical characterisation of the volatile compounds in a South African herbal plant reported to date. A comparative study of green and fermented honeybush showed that the same compounds are, to a large extent, present in both, albeit in different relative concentrations. Not all of the identified honeybush volatiles are necessarily odour-active compounds contributing to the overall typical honeybush aroma. An important aspect of this research was thus the identification of the 46 odour-active compounds in fermented honeybush by means of gas chromatography-olfactometry (GC-O), using detection frequency and aroma extract dilution analysis methods. Fifteen of these compounds, mainly terpenoids, were singled out as the most intense individual contributors to the honeybush aroma based on consideration of all the relevant GC-O data. The odours of certain compounds, i.e. (6E,8Z)-megastigma-4,6,8-trien-3-one, (6E,8E)-megastigma- 4,6,8-trien-3-one, (7E)-megastigma-5,7,9-trien-4-one, 10-epi- -eudesmol, epi- -muurolol and epi- - cadinol, were perceived by GC-O assessors as typically honeybush-like. The quantitative GC-MS data of seven different Cyclopia samples (including four different species and variants thereof) were compared with respect to all the volatile components and particularly with respect to the odour-active compounds. Interesting variations were found in the concentrations of certain odour-active compounds in the various samples. The quantitative data obtained for the odour-active honeybush volatiles and data obtained from the sensory analysis of eight Cyclopia samples (including four different species and variants thereof) were subjected to statistical analysis and interesting associations between compounds with certain sensory aroma attributes were established. The present study has made a major contribution to the scientific knowledge regarding one of South Africa’s most popular indigenous herbal teas.
AFRIKAANSE OPSOMMING: Heuningbostee, wat ook bekend staan as “Suid-Afrika se soetste tee”, word gemaak van die blare en takkies van Cyclopia spp. wat inheems is en voorkom in die fynbosbioom van die Wes- en Oos-Kaapprovinsies van Suid-Afrika. Die aangename soet smaak en aroma van gefermenteerde heuningbos, die lae tannnien-inhoud en die feit dat die tee kafeïenvry is, het gelei tot belangstelling in die kommersiële verbouing en prosessering van heuningbostee gedurende die 1990s. Meer as 20 heuningbosspesies kom in die natuur voor, maar slegs ‘n paar spesies word kommersieel verbou vir die vervaardiging van heuningbostee waarvan C. intermedia, C. subternata, C. genistoides en C. sessiliflora tans die belangrikste spesies is. Die navorsing maak deel uit van ‘n omvattende heuningbos navorsingsprogram wat onder leiding staan van die Landbounavorsingsraad Infruitec- Nietvoorbij in Suid-Afrika. In die eerste fase van die huidige studie is die nodige analitiese metodologie ontwikkel vir die monsterneming en analise van die vlugtige organiese verbindings wat in uiters lae konsentrasies in heuningbos voorkom, deur van ‘n verteenwoordigende spesie, C. genistoides, gebruik te maak. ‘n Sogenaamde “sample enrichment probe” (SEP) is ontwikkel en suksesvol in kombinasie met gaschromatografie-massaspektrometrie (GC-MS) aangewend vir die analise van die vlugtige verbindings aanwesig in die bodamp van sowel droë plantmateriaal as infusies van ongefermenteerde en gefermenteerde heuningbos. ‘n Totaal van 255 vlugtige verbindings is geïdentifiseer, waarvan die meeste hoofsaaklik terpenoïede is (138, 54%) en terpene, terpeenketone, terpeenalkohole en terpeeneters insluit. Die ander verbindingsgroepe, waarvan die aldehiede die grootste groep is, sluit in esters, koolwaterstowwe en ketone. Indien haalbaar, is die stereochemie van die geïdentifiseerde verbindings ook bepaal. Hierdie studie is die mees omvattende chemiese karakterisering van die vlugtige verbindings in ‘n Suid-Afrikaanse kruieplant wat tot dusver onderneem is. ‘n Vergelykende studie het getoon dat ongefermenteerde en gefermenteerde heuningbos tot ‘n groot mate dieselfde verbindings, hoewel in verskillende relatiewe konsentrasies, bevat. Nie al die geïdentifiseerde vlugtige verbindings in heuningbos is noodwendig aroma-aktiewe verbindings wat ‘n bydrae tot die algehele tipiese heuningbosaroma lewer nie en daarom was die identifisering van die 46 aroma-aktiewe verbindings in geferementeerde heuningbos deur gebruik te maak van gaschromatografie-olfaktometrie (GC-O) deur middel van deteksiefrekwensie en aroma ekstrak verdunningsanalise, ‘n belangrike aspek van die navorsing. Na oorweging van al die tersaaklike GC-O data is 15 van hierdie verbindings, hoofsaaklik terpenoïede, uitgesonder as die verbindings wat die belangrikste bydrae tot die heuningbosaroma lewer. Die reuke van sekere van die verbindings, nl. (6E,8Z)-megastigma-4,6,8-triën-3-oon, (6E,8E)-megastigma-4,6,8-triën-3-oon, (7E)-megastigma-5,7,9-triën-4-oon, 10-epi- -eudesmol, epi- -muurolol, en epi- -cadinol, is deur sommige van die GC-O paneellede as tipies heuningbosagtig beskryf. Die kwantitatiewe GC-MS data van sewe verskillende Cyclopia monsters (insluitende vier verskillende spesies en variante daarvan) is vergelyk met betrekking tot al die vlugtige verbindings, asook veral met betrekking tot die aroma-aktiewe verbindings. Interessante variasies in die konsentrasies van sekere aroma-aktiewe verbindings is in die verskillende monsters waargeneem. Die kwantitatiewe data van die aroma-aktiewe heuningbosverbindings en data verkry uit die sensoriese analise van agt Cyclopia monsters (insluitende vier verskillende spesies en variante daarvan), is onderwerp aan statistiese analises waaruit interessante assosiasies tussen verbindings met sekere sensoriese aroma-eienskappe waargeneem is. Hierdie studie lewer ‘n groot bydrae tot die wetenskaplike kennis aangaande een van Suid- Afrika se mees populêre inheemse kruietees.
Rogers, Ilva Margaret. "Some aroma compounds of importance to the quality of Ferdinand de Lesseps and Kerner wines." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51911.
Full textENGLISH ABSTRACT: Ferdinand de Lesseps grapes have a distinctive fruity varietal character and were often used judiciously by wine-makers to enhance the fruity bouquet of some white table wines. Ferdinand de Lesseps grape juice was investigated to identify the main contributing compounds responsible for its unique and intense aroma. The juice was recovered from grapes under anaerobic conditions and extracted using Freon 11. The concentrated extract was analysed using a combination of capillary gas chromatography-mass spectrometry and gas chromatography-sniffing techniques. Thirty-two compounds were reported. With the aid of GC-sniffing, it was concluded that the hybrid note of the Ferdinand de Lesseps grape was most likely attributed to the presence of 2,5-dimethyl-3(2H)-furanone and 0- aminoacetophenone. Esters, which featured prominently in the juice, consisted mainly of ethyl butanoate, ethyl- and methyl- 3-hydroxy butanoate, and to a lesser extent, ethyl 3- hydroxy hexanoate and ethyl-3-hydroxy propanoate. These esters are most likely responsible for the sweetish pineapple aroma. According to EEC regulations, the use of non- Vinifera grapes in the production of commercial wines is prohibited. The presence of 2,5-dimethyl- 3(2H)-furanone in wine could therefore be interpreted as a labrusca indicator should it be suspected that Ferdinand de Lesseps grapes were used in the blend. The quality of some South African Kerner table wines often is rated inferior owing to an unwanted odour described as "Elastoplast" or "medicinal". This odour is encountered occasionally in wines from other cultivars such as Gewurztraminer, Weisser Riesling, Muscat de Frontignan and Chenin blanc. The identification of the compounds responsible for the offodour was investigated, as well as possible relationships between its occurrence and viniviticultural practices. The compound responsible for the "medicinal" off- odour was identified as p-vinyl guaiacol. It is formed via decarboxylation of ferulic acid by yeast during alcoholic fermentation. lts concentration is directly related to the concentration of ferulic acid and the yeast strain. Other factors affecting p-vinyl guaiacol formation in Kerner wines are region, microclimate, exposure of grapes to sunlight and grape maturity. Wines made from grapes harvested from the warmer climatic regions and exposed to direct sunlight and increased maturity contained higher levels of p-vinyl guaiacol. Viticultural practices that can be applied to limit the formation of the p-vinyl guaiacol precursor in grapes are the use of a canopy manipulation to protect the grapes from direct sunlight and an earlier harvesting date. Various winemaking techniques can be used to lower p-vinyl guaiacol levels in wine. Careful consideration must be given to the choice of yeast, as different yeast strains differ considerably with their ability to form p-vinyl guaiacol. Fining oxidised grape juice with phenol adsorbing agents such as activated charcoal, polyvinylpolypirrollidone, casein, gelatin (particularly in combination with bentonite and "kieselsol") led to decreases in the p-vinyl guaiacol levels. Although fining with activated charcoal was the most effective must treatment for reducing the "medicinal" aroma of Kerner wines, it stripped the wines of colour and character. Excessive oxidation of must followed by fining involves extra costs and time for the winemaker and would not be used in making the reductive style of wines.
AFRIKAANSE OPSOMMING: Ferdinand de Lesseps druiwe en wyne vertoon unieke vrugtige varieteitskarakter en is dikwels deur wynmakers in versnitte gebruik om die geur van sekere wit tafelwyne te verbeter. In hierdie studie is Ferdinand de Lesseps druiwe ondersoek om die belangrikste komponente wat verantwoordelik is vir die prominente, unieke aroma daarvan te identifiseer. Die sap is onder anaerobe toestande herwin en met Freon 11 ekstraheer. Die gekonsentreerde ekstrakte is met behulp van 'n kombinasie van kapillêre gaschromatografie-massaspektrometrie en gaschromatografie-snuif tegnieke analiseer. Twee-en-dertig komponente is gerapporteer. Met die behulp van GC-snuiftegnieke is bevestig dat die hibried karakter in Ferdinand de Lesseps druiwe hoofsaaklik aan die teenwoordigheid van o-amino-asetofenoon en 2,5-dimetiel-3(2H)- furanoon toegeskyf kan word. Die vernaamste esters in die sap was etielbutanoaat, etiel- en metiel-3-hidroksibutanoaat en in 'n mindere mate etiel-3-hidroksiheksanoaat en etiel-3- hidroksipropanoaat. Dié esters is waarskynlik verantwoordelik vir die soet pynappel aroma. Volgens EEG regulasies word die gebruik van nie- Vinifera druiwe vir die produksie van komersiéle wyne verbied. Die teenwoordigheid van 2,5-dimetiel-3(2H)-furanoon in wyn kan dus interpreteer word as 'n labrusca indikator in gevalle waar gebruik van Ferdinand de Lesseps druiwe vermoed word. Die kwaliteit van sommige Suid-Afrikaanse Kerner wyne word dikwels verlaag vanweë die teenwoordigheid van 'n geur wat beskryf word as "Elastoplast" of "medisinaal". Dié reuk word soms waargeneem in wyne van ander kutivars soos Gewurztraminer, Weisser Riesling, Muskaat de Frontignan en Chenin blanc. Die identiteit van die komponent wat vir dié ongewenste reuk verantwoordelik is, asook moontlike verwantskappe met wingerd- en wynkundige praktyke is ondersoek. Die komponent wat vir die medisinale karakter verantwoordelik is, is geïdentifiseer as para-vinielguajakol. Dit word deur dekarboksilasie van feruliensuur deur gisselle tydens alkoholiese gisting gevorm. Die konsentrasie van paravinielguajacol in wyn is direk verwant aan die konsentrasie feruliensuur en die gisras. Ander faktore wat para-vinielguajacol-vorming in Kerner wyn affekteer is streek, mikroklimaat, blootstelling van druiwe aan direkte sonlig en die rypheidsgraad van die druiwe. Wyne wat berei is van ryper druiwe uit warmer streke en wat direk aan sonlig blootgestel was, het hoër konsentrasies para-vinielguajacol bevat. Lowerbestuurspraktyke met behulp waarvan druiwe teen direkte sonligblootstelling beskerm word, is van die vernaamste wingerdkundige praktyke wat aangewend kan word om die vorming van die voorlopers van paravinielguajacol in druiwe te verlaag. Verskeie wynbereidingstegnieke kan gebruik word om die para-vinielguajacol vlakke in wyn te verlaag. Gisraskeuse is van besondere belang omdat gisrasse grootliks verskil in hul vermoë om para-vinielguajacol te vorm. Breibehandelings van geoksideerde sap met middels soos geaktiveerde koolstof, PVPP, kasseïen, gelatien (veral in kombinasie met bentoniet en "kieselsol") het die vlakke van para-vinielguajacol in wyne verlaag. Hoewel geaktiveerde koolstof die doeltreffendste breimiddel vir die verlaging van para-vinielguajacol was, het dit te veel kleur en geur uit die wyn verwyder. Oormatige oksidasie van mos gevolg deur breibehandelings sal meer geld en tyd verg en word nie aanbeveel vir wyne wat in 'n reduktiewe styl berei word nie.
Jelínková, Monika. "Stanovení vonných látek rostlinného původu v potravinách." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216549.
Full textMelikantová, Marcela. "Stanovení aromaticky aktivních látek v odrůdách rakytníku řešetlákového." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217028.
Full textSganzerla, Marla 1986. "Study of capsaicinoids and volatile compounds in Brazilian Capsicum chinense peppers = Estudo de capsaicinoides e compostos voláteis em pimentas brasileiras Capsicum chinense." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254303.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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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
Maróstica, Junior Mário Roberto 1980. "Biotransformação de terpenos para a produção de compostos de aroma e funcionais." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/256710.
Full textTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Este trabalho teve por objetivos o estudo da biotransformação de terpenos e avaliação de suas propriedades biológicas. A biotransformação de limoneno foi realizada por uma linhagem de Fusarium oxysporum cultivada em manipueira e transferida para meio mineral, sendo o óleo essencial de laranja, um resíduo da indústria do suco de laranja, a fonte do limoneno. Rendimentos da ordem de 450 mg/L de a-terpineol, o principal produto obtido, foram alcançados. Da mesma forma, a biotransformação do citronelol foi conduzida por uma linhagem de Penicillium sp. cultivada em manipueira e transferida para meio mineral. O principal produto obtido foi o cis-óxido de rosa em concentrações da ordem de 70 mg/L. A seleção de microrganismos biotransformadores de limoneno (cuja fonte foi óleo essencial de laranja) a- e b-pinenos (cuja fonte foi terebentina, resíduo industrial da indústria de papel) foi realizada por microextração em fase sólida (MEFS). A técnica mostrou-se eficaz para a recuperação de voláteis presentes no 'heapspace¿ de culturas esporuladas de superfície para a biotransformação. Os microrganismos selecionados por MEFS foram submetidos à biotransformação em cultura líquida e produção da ordem de 50 mg/L de verbenol por Mucor sp. 2276 e 70 mg/L de verbenona resultaram da biotransformação de a- e b-pinenos. Aspergillus sp. 2357 e Penicillium sp. 2360 produziram aproximadamente 90 e 10 mg/L de a-terpineol e álcool perílico respectivamente. A biotransformação de a-farneseno por linhagens de Aspergillus niger gerou compostos nunca relatados anteriormente na literatura. Quatro produtos principais foram obtidos. Apenas um composto pôde ser identificado por meio de CG-EM como 6-OH-farneseno. Análises de CG-olfatometria descreveram 6-OH-farneseno como aroma cítrico impactante. Estudos 'in vitro¿ e 'in vivo¿ com extrato da biotransformação de limoneno por Fusarium oxysporum e com padrões de monoterpenos revelaram o potencial desses compostos em atuarem como antioxidantes, gerando uma possibilidade para esses compostos serem utilizados industrialmente como aromas funcionais
Abstract: The biotransformation of terpenes and their functional properties were investigated in this study. The biotransformation of limonene was done by a Fusarium oxysporum strain grown in cassava waste water and transferred into a mineral medium for biotransformation. The limonene source was an orange essential oil from a orange juice industry. The main biotransformation product was a-terpineol, reaching around 450 mg/L. Similarly, biotransformation of citronellol was conducted by a Penicillium sp. strain grown also in cassava waste water and transferred into a mineral medium. The main product was cis-rose oxide, reaching concentrations higher than 70 mg/L. The screening of microrganisms for biotransformation of limonene (from orange essential oil) and a-, b-pinenes (from turpentine oil, residue from pulp industry) was done by solid phase microextraction (SPME). The technique was effective for the recovery of the volatiles from the headspace of sporulated surface biotransformation cultures. Liquid culture biotransformation experiments performed with the SPME screened strains resulted in the production of 50 mg/L of verbenol by Mucor sp. 2276 and 70 mg/L of verbenone form a-, b-pinenes and 90 mg/L of a-terpineol by Aspergillus sp. 2357 and 10 mg/L of perillyl alcohol by Penicillium sp. 2360. The biotransformation of a-farnesene by Aspergillus niger strains resulted in compounds never described in the literature before. Four main new compounds were obtained. Only one of them could be identified by GC-MS as 6-OH-farnesene. CG-O experiments revealed the impactant citrus aroma of 6-OH-farnesene. 'In vitro¿ and 'in vivo¿ experiments with the limonene biotransformation extract by Fusarium oxysporum and with the monoterpene standards present in the extract revealed the antioxidant potential of these compounds, which open a new perspective for the utilization of these compounds as functional aroma compounds
Doutorado
Doutor em Engenharia de Alimentos
Heilig, Andrej [Verfasser]. "The interaction of aroma compounds and dairy constituents: influence of composition and processing on aroma retention and transport in liquid to semi-solid matrices / Andrej Heilig." München : Verlag Dr. Hut, 2013. http://d-nb.info/1033041289/34.
Full textQuelhas, Jaime Miguel Pombo. "Relação entre a composição mineral do vinho e a ocorrência do aroma a reduzido." Master's thesis, ISA, 2011. http://hdl.handle.net/10400.5/8496.
Full textThe present work is intended investigate the incidence of defect reduction in the several types of wine and the effect of treatments made with copper metal in their composition. For this purpose, was made a retrospective analysis of incidence of the defect between 2004 and 2010, in the various types of wine produced in the winery under study. The wines seem more susceptible to be the red, while the rosé, whose production has increased significantly in recent years, also showed high incidences Merely on an empirical basis, the defect appears be associated with harvest earliest and longer fermentation. As a result of the addition of copper sulphate, in order to resolving the problem of reduced wines, the only metal whose concentration was significantly increased copper. However, this increase did not change the general balance of the remaining metals in wine. Thus, for the multielement analysis we observed that treatment with copper did not affect the composition of metals in order to prevent a breakdown of samples according to the origin.
Cairns, Paulette Anne. "Effects of Hydroxycinnamates and Exogenous Yeast Assimilable Nitrogen on Cider Aroma and Fermentation Performance." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/101679.
Full textMaster of Science in Life Sciences
Holzmayr, Stefan [Verfasser]. "Characterization of key aroma compounds of celeriac, carrot, navet, onion and leek and their contribution to the aroma of the meat bouillon Pot-au-Feu / Stefan Holzmayr." München : Verlag Dr. Hut, 2018. http://d-nb.info/1176250965/34.
Full textSerughetti, Alessandro. "Influences of the amino acids during alcoholic fermentation and development of aroma compounds in Sauvignon blanc." Master's thesis, ISA, 2017. http://hdl.handle.net/10400.5/15840.
Full textIn recent years, New Zealand in terms of production has expressed a certain respect and attention towards Sauvignon Blanc for its organoleptic chemical characteristics. In this project seven different amino acids were used, two blend of amino acids and the DAP (di-ammonium phosphate) used in wineries, with the aim of investigating the effect of different levels of nitrogenous source of musts from the two different vineyards ( Omaka Vineyard and Gifford's Creek Vineyard), on the progress of fermentation and the impact on the aromatic component, with the use of the "New Zealand Grape and Wine Research Program" winemaking protocols, with all the processes being reduced to improve the aromatic quality of Sauvignon Blanc in the Marlborough region of New Zealand. This experimental thesis project with the title "Influences of amino acids during alcoholic fermentation and the development of aromatic compounds in Sauvignon Blanc", observes the single amino acids added starting from two musts, with different initial nitrogenous source, and examines the reaction from the yeast during alcoholic fermentation, with reference to the type of free aromatic compounds and their concentration
N/A
Škopová, Jitka. "Stanovení vybraných vonných látek v potravinách." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2010. http://www.nusl.cz/ntk/nusl-216620.
Full textAscherová, Adriana. "Stanovení vybraných vonných látek v potravinách." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216714.
Full textGross, Michal. "Studium aromatického profilu vybraných odrůd moravských vín." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449742.
Full textNovotná, Petra. "Stanovení vybraných vonných látek v kosmetických prostředcích." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-216705.
Full textFord, Rebecca Jane. "The effect of shading and crop load on flavour and aroma compounds in Sauvignon blanc grapes and wine." Master's thesis, Lincoln University. Agriculture and Life Sciences Division, 2007. http://theses.lincoln.ac.nz/public/adt-NZLIU20080523.100013/.
Full textFord, R. J. "The effect of shading and crop load on flavour and aroma compounds in Sauvignon blanc grapes and wine." Lincoln University, 2007. http://hdl.handle.net/10182/498.
Full textSaxton, Valerie Patricia. "Influence of ripening grape compounds on behavioural responses of birds." Phd thesis, Lincoln University. Agriculture and Life Sciences Division, 2004. http://theses.lincoln.ac.nz/public/adt-NZLIU20061207.121738/.
Full textNorton, Jenny Lynn. "Efficacy of Odor Scavengers in Reducing Odor Compounds in Water, Milk, and Soymilk." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/45094.
Full textMaster of Science
Kumar, Mona. "Use of plant-derived essential oil compounds, naturally-occurring apple aroma compounds, and apple juice flavoring mixtures to control the growth of Escherichia coli O157:H7." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/49564.
Full textThe standard agar dilution method (SAD) and checkerboard assay were used to evaluate the efficacy of the nine compounds, alone and in combination against E. coli O157:H7. In general, the EO compounds were significantly more effective against E. coli O157:H7 than the AA compounds (P<0.05). Cinnamaldehye, with an MIC of 0.2 mg/mL, exhibited the highest degree of activity, followed by thymol, eugenol and trans-2-hexenal, which each had individual MIC values of 1.6 mg/mL. No synergism was found in the combinations of EO compounds with AA compounds.
Master of Science in Life Sciences
Rambla, Nebot Jose Luis. "GENES AND GENOMIC REGIONS RELATED TO THE PRODUCTION OF VOLATILE COMPOUNDS IN THE TOMATO FRUIT." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/61768.
Full text[ES] Los frutos producen y emiten compuestos químicos volátiles. Estos son moléculas en general poco polares y de cadena corta que cumplen diversas funciones, y son las responsables de que percibamos el aroma y buena parte del sabor de los frutos. Esta tesis está centrada en el estudio de los volátiles del fruto del tomate, que es uno de los cultivos hortícolas más importantes y un sistema modelo para el estudio del desarrollo y maduración del fruto. Se compararon de forma sistemática los métodos analíticos más comúnmente utilizados para el análisis de volátiles en fruto de tomate, y se observó que el perfil de volátiles detectado está fuertemente condicionado por el método analítico utilizado, tanto por el proceso de preparación de la muestra como por la técnica de adquisición de los volátiles. Finalmente se concluyó que la técnica más adecuada para la comparación de grandes grupos de muestras desde una aproximación multi-ómica consiste en congelar con nitrógeno líquido el material vegetal una vez alcanzado el momento idóneo de recolección, y su análisis posterior mediante microextracción en fase sólida (SPME) acoplada a cromatografía de gases y espectrometría de masas. Se puso a punto esta técnica y se utilizó para la determinación de los compuestos volátiles en varias líneas NILs portadoras de QTLs de caracteres relacionados con el sabor y el aroma en distintos fondos genéticos. Los resultados permitieron asociar varios de los caracteres organolépticos identificados con alteraciones en los niveles de algunos volátiles. Igualmente se observó que el fondo genético tiene un efecto importante sobre la producción de estos metabolitos. Los análisis de correlación entre los niveles de volátiles y metabolitos primarios permitieron concluir que la producción de compuestos volátiles, en general, no está determinada por los niveles de sus precursores, sino que su regulación debe encontrarse más bien en procesos posteriores, tales como la disponibilidad de los precursores o de metabolitos intermedios, variabilidad en procesos específicos relacionados con la conversión de los precursores en volátiles, o algún otro mecanismo regulador aún desconocido. También se estudiaron los volátiles en una población de RILs derivada de un cruce entre Solanum pimpinellifolium entrada TO-937, la especie más próxima al tomate cultivado, la cual produce frutos rojos, y S. lycopersicum cv. "Moneymaker", una variedad de tomate para el mercado en fresco. Esto permitió identificar 102 QTLs para 39 volátiles diferentes, 76 de las cuales no se habían descrito previamente, las cuales se mapearon a lo largo de los 12 cromosomas del tomate utilizando el mapa de marcadores moleculares de SNPs SOLCAP. Posteriormente se evaluaron la mayoría de las QTLs identificadas mediante la determinación de los volátiles en líneas ILs generadas a partir de los mismos materiales. Se observó que casi la mitad de estas QTLs mantuvieron su efecto al ser introgresadas en el fondo genético "Moneymaker", al tiempo que 12 nuevas QTLs se identificaron en esta población de ILs. Algunas de las QTLs identificadas, en base al conocimiento existente sobre el efecto de los compuestos volátiles en nuestra percepción del sabor y el aroma, y en base a su capacidad para mantener su efecto tras su introgresión en el tomate cultivado, resultan ser candidatos prometedores para su utilización en la mejora genética del sabor del tomate. Finalmente, el análisis de la localización en el genoma de las QTLs analizadas en las distintas poblaciones objeto de estudio en esta tesis, junto con las descritas en la bibliografía disponible, puso de relieve el bajo grado de co-localización existente entre las distintas QTLs, lo cual implica que en las especies silvestres relacionadas con el tomate existe un amplio rango de variabilidad genética susceptible de ser utilizado para la mejora de su sabor y su aroma.
[CAT] Els fruits produixen i emitixen compostos químics volàtils. Estos són molècules en general de baixa polarita i cadena curta que tenen diverses funcions, i són les responsables de la nostra percepció de l'aroma i de bona part del sabor dels fruits. Esta tesi està centrada a l'estudi dels volàtils del fruit de la tomata, que és un dels cultius hortícoles més importants i un sistema model per a l'estudi del desenvolupament i la maduració del fruit. Es van comparar de forma sistemática els mètodes analítics més habituals per a l'anàlisi de volàtils en fruits de tomata, i es va observar que el perfil de volàtils detectat està fortament condicionat per el mètode analític utilitzat, tant per el procés de preparació de la mostra com per la técnica d'adquisició dels volàtils. Es va concluir que la t`cnica més adequada per a la comparació de grans grups de mostres desde una aproximació multi-òmica consistix en congelar en nitrògen líquid el material vegetal en el momento idoni de recolecció, i analitzar-lo posteriorment per microextracció en fase sòlida (SPME) acoplada a cromatografía de gasos i espectrometría de masses. Es va posar a punt esta técnica i es va utilitzar per a la determinació dels composteos volàtils en varies línies NILs portadores de QTLs de caràcters relacionats en el sabor i l'aroma en fons genètics diversos. Els resultats van permetre associar alguns dels caràcters organolèptics identificats en alteracions en els nivells d'alguns compostos volàtils. També es va observar que el fons genètic té un efecte important sobre la producción d'estos metabolits. Els anàlisi de correlació entre els nivells de volàtils i els metabolits primaris ens van permetre concluir que la producción de compostos volàtils, en general, no està determinada per els nivells dels seus precursors. La seua regulació és deguda a procesos posteriors, com la disponibilitat dels precursors o de metabolits intermediaris, la variabilitat en processos específics relacionats en la conversió dels precursors en volàtils, o en algún altre mecanisme regulador encara desconegut. També es van estudiar els volàtils en una población de RILs rerivada d'un creuament entre Solanum pimpinellifolium entrada TO-937, la espècie silvestre més próxima a la tomatera cultivada i que produix fruits rojos, i S. lycopersicum cv. Moneymaker, una varietat de tomata per al mercat en fresc. Açò va permetre l'identificació de 102 QTLs de 39 volàtils diferents, 76 de les quals no s'havien descrit prèviament, i que es van mapejar al llarg dels 12 cromosomes de la tomatera mitjançant el mapa de marcadors moleculars de SNPs SOLCAP. Posteriorment es van evaluar la majoria de les QTLs identificades mitjançant la determinació dels volàtils en línies ILs generades a partir dels mateixos materials. Es va observar que quasi la meitat de estes QTLs van mantindre el seu efecte al ser introgressades en el fons genètic "Moneymaker". Adicionalment, 12 noves QTLs es van identificar en esta población d'ILs. Algunes de les QTLs identificades, en base al coneiximent existent respecte a l'efecte dels volàtils en la nostra percepció del sabor i l'aroma, i tenin en cónter la seua capacitat de mantindre el seu efecte al ser introgressats en la tomata cultivada, són candidats prometedors per a ser utilitzats en la millora genética del sabor de les tomates. Finalment, l'anàlisi de la localització en el genoma de les QTLs analitzades en les distintes poblacions objecte d'aquesta tesi, junt a les descrites en la bibliografía disponible, va evidenciar que existix una baixa freqüència de co-localització entre les distintes QTLs. Açò implica que existix molta variabilitat genética en les espècies silvestres relacionades en la tomatera, que pot ser utilitzada per a la millora del sabor i l'aroma dels seus fruits.
Rambla Nebot, JL. (2016). GENES AND GENOMIC REGIONS RELATED TO THE PRODUCTION OF VOLATILE COMPOUNDS IN THE TOMATO FRUIT [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61768
TESIS
Premiado
Ifie, Idolo. "The effect of processing conditions on the bioactive compounds, aroma profile and sensory attributes of wine from Hibiscus sabdariffa." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15674/.
Full textPallová, Jana. "Příprava a charakterizace extraktů echinacey." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449758.
Full textFreiberger, Eliza Brito. "Nanocápsulas de poli (L-ácido lático) contendo óleo de café torrado." Universidade Tecnológica Federal do Paraná, 2013. http://repositorio.utfpr.edu.br/jspui/handle/1/1079.
Full textO aroma de café é constituído por uma mistura de componentes voláteis, os quais podem ser encontrados no óleo obtido na torração do café. O café solúvel, em função das condições de processamento, perde parte do seu aroma que, a princípio, poderia ser reincorporado ao produto pela adição do óleo de café diretamente sobre o produto final. Contudo, alguns trabalhos apontam para dificuldades de se obter bons resultados quando se trabalha com o óleo in natura devido à sua volatilidade e à degradação dos aromas. A incorporação de nanocápsulas contendo o óleo de café pode ser uma alternativa para minimizar estas perdas, pois o polímero encapsulante pode agir como barreira de proteção e promover sua liberação de forma controlada. A proposta do trabalho é a obtenção de nanocápsulas de poli(L-ácido lático)(PLLA), contendo o óleo de café torrado pela técnica de miniemulsificação/evaporação do solvente e validar o método para quantificação do óleo de café por espectrofotometria UV-Vis. Os estudos de validação possibilitaram garantir a qualidade dos resultados obtidos. Formulações com diferentes concentrações de PLLA, óleo e tipos de surfactantes foram valiadas quanto ao tamanho e índice de polidispersão frente à recuperação de óleo. Todas as formulações testadas apresentaram valores de recuperação de óleo acima de 80% mostrando que a técnica é adequada e pode ser considerada uma alternativa promissora para produzir nanocápsulas contendo óleo de café. As análises da composição do aroma das nanocápsulas, que indica a qualidade da porção de óleo encapsulada, mostraram que as nanocápsulas contêm frações de todos os compostos encontrados no óleo.
Coffee flavor is a mixture of volatile components found in the oil obtained from the roasted coffee. Soluble coffee loses part of its aroma due to processing conditions which could be reintroduced to the product by the direct addition of the coffee oil. However, some studies point out difficulties in obtaining good results when working with in natura oil because of the high volatility and the flavor degradation. The incorporation of nanocapsules containing coffee oil could be an alternative to minimize these losses, because the encapsulating polymer could act as a protecting barrier and promote its controlled release. The aim of this work is obtain PLLA nanocapsules containing roasted coffee oil by the miniemulsification/solvent evaporation technique. The spectrophometric UV- Vis method used to quantify the coffee oil was validated. Formulations with different PLLA and oil concentrations and kind of surfactant were evaluated in respect to the average nanocapsules size and polydispersion index and oil recovery. All formulations demonstrated oil recovery values above 80 % demonstrating that the technique is adequate and can be consider a promising alternative to coffee oil nanocapsules production. Flavor analysis nanocapsules composition, which indicates the quality of the encapsulated oil, showed that the nanocapsules contain fractions of all the substances found on the in natura oil.
Pospíchalová, Alžběta. "Srovnání aromatického profilu kozího vs. kravského mléka." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401885.
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