This master thesis deals with the assessment of aroma active compounds in fruits of currant (Ribes spp.). The theoretical part was focused on basic characteristics and chemical composition of currants, as well as the basic principles of techniques used: solid phase micro extraction (SPME), gas chromatography (GC) and sensory analysis. The main aim of the experimental part was to determine aroma active compounds in currants using SPME-GC-FID method. The profile and scale tests were used for assessment of sensory quality and tastiness of fruits. In total 18 varieties, among them 6 white, 6 red and 6 black currants, were evaluated. Fifty aroma active compounds were identified including 21 alcohols, 10 aldehydes, 2 acids, 8 ketones and 9 esters. The results were statistically evaluated using principal component analysis (PCA) to investigate the influence of single compounds on sensory quality of fruits.

This diploma thesis is focused on the problematic of assessment of allergenic aroma compounds in various matrices. In the frame of European legislation 26 of potentially allergenic compounds are stated, whose content in cosmetic products is limited. In the case of foods there is not such restriction so far. In the experimental part, the allergenic aroma compounds in chosen samples of cosmetic and food samples were identified and quantified using Solid phase microextraction in conjunction with gas chromatography. Sensory evaluation of aroma or taste is also included.

This thesis deals with the determination of aroma active compounds in non-chocolate confectionery and their influence on the sensory properties of these sweets. The theoretical part is focused on the 26 potentially allergenic substances and their determination by SPME-GC-FID (a solid phase microextraction, gas chromatography with flame ionisation detector) and sensory analysis. In the experimental part SPME-GC-FID method was used to identify and quantify aroma active substances contained in the selected samples of confectioneries commonly available in food market and find out influence of presence and amounts of these substances on sensory profile of selected confectionery.

This thesis deals with aroma active compounds of selected types of medicinal herbs, specifically lavender (Lavandula officinalis), peppermint (Mentha piperita), sage (Salvia officinalis), St. John’s wort (Hypericum perforatum) and hyssop (Hyssopus officinalis). In the theoretical part the single herbs were characterized including botanical description, chemical composition, medicinal properties, adverse effects and the practical use; aroma active compounds present in herbs are also emphasized. Based on the literature search, gas chromatography coupled with mass spectrometry as currently the most frequently used method, was chosen for the assessment of aroma compounds. Solid Phase Microextraction was used for isolation of volatile compounds from dried herbs. Within experimental part of the work selected parameters of the SPME-GC-MS method were optimized, aroma compounds in samples of herbs were identified, and twenty four suspected fragrance allergens due to the Regulation (EC) N° 1223/2009 were also identified and quantified. Overall 69 compounds were indetified together with 2 allergens in lavender, 59 compounds including 5 allergens in peppermint, sage contained 49 compounds with 4 allergens included, 41 compounds were identified in St. John’s wort including 4 allergens and finally 64 compounds with 4 allergens included in hyssop.

The aim of the work was identification of aroma active compounds in Moravský bochník cheese type, than discuss their changes during ripening and consider influence of aplication different rates of microbial cultures on number of volatile compounds. SPME-GC-MS was used for identification of volatile compounds. In total, 148 of volatile compounds were identified and 82 of them are considered as aroma active compounds. Three microbial cultures (their combination with predominant thermophilic or mesophilic culture) were used for making samples. The influence of predominant thermophilic/mesophilic culture on number of volatile compounds was not proved. From the point of view of sensory quality, combinations with predominant mesophilic culture proved to be more successful. During ripening, the number of identified compounds was reduced in all the combinations of cultures studied. The optimal time for ripening seems to be three months.

Les fermentations alcoolique (FA) et malolactique (FML) sont deux étapes importantes de la vinification en rouge dans l’établissement de l’arôme fruité des vins. Afin d’étudier l’importance relative des microorganismes fermentaires, nous étudions l’influence de six couples levures/bactéries lactiques (BL) - trois souches de levures, deux de BL - sur la modulation des notes fruitées de différents vins rouges de Bordeaux. Une première approche analytique montre l’influence prédominante de la souche de levures sur la concentration de plus de 70 marqueurs potentiels de la note fruitée. L’étude particulière des esters montre que l’effet levures observé dès la fin de la FA persiste au cours du temps malgré la FML et les modifications engendrées par le vieillissement du vin. L’étude sensorielle conforte l’influence majeure des levures sur la modulation de l’arôme fruité des vins rouges à différents temps d’élevage. Néanmoins, les résultats obtenus suggèrent l’implication d’autres composés aromatiques dans la modulation de la note fruitée des vins, non quantifiés dans la première partie de cette étude. Un travail de fractionnement d’extraits de vin par HPLC permet par la suite l’identification d’une fraction d’intérêt impliquée dans des variations aromatiques liées à la souche de levures. L’analyse de cette fraction par chromatographie en phase gazeuse n’a pas permis d’identifier le ou les composés impliqués. Nous avons néanmoins mis en évidence une thiophénone qui pourrait agir en tant que masque de l’arôme fruité, ainsi qu’un ester hydroxylé qui pourrait s’avérer être un marqueur intéressant de l’activité bactérienne et dont l’effet exhausteur de notes fruitées est également envisagé comme perspectives. / Alcoholic (AF) and malolactic (MLF) fermentations are important steps in red winemaking for the revelation of wine fruity aroma. To investigate the relative importance of fermentative microorganisms, we studied the influence of six yeasts/lactic acid bacteria (LAB) combination - three yeast strains, two LAB - on Bordeaux red wines fruity notes modulation. A first analytical approach showed the predominant influence of yeast strain on the concentration of more than 70 potential fruity note markers. Special study of esters showed a yeast strain effect since the end of FA that persists over time, despite MLF and changes caused by wine aging. Sensory studies also highlighted the major influence of yeasts on red wines fruity aroma modulations at different aging steps. Nevertheless, results suggested the role of other aromatic compounds in fruity note modulation, not quantified in the first part of this study. The study of fractions made by HPLC with wine organic extracts enables the identification of an interested fraction involved in aromatic variations related to the yeast strain. Analysis of this fraction by gas chromatography has not allowed identifying compounds involved in these organoleptic variations. However, we highlighted a thiophenone that could act as a mask of fruity aroma and a hydroxylated ester that could be an interesting marker of bacterial activity. Its role as enhancer of fruity esters aroma is also considered.

Tesis por compendio / [EN] Fruits both produce and emit volatile chemical compounds. These are short-chained low polarity molecules involved in many processes, and they are responsible of our perception of fruit aroma and of most of their flavour. This thesis is focused on the study of volatile compounds in the tomato fruit, which is one of the most important horticultural worldwide and is a model system for the study of fruit development and ripening. Some of the analytical methods more frequently used for the analysis of tomato fruit volatiles were systematically compared. Results revealed that the observed volatile profile is highly dependent on the precise analytical method used, both for sample processing and for the technique used for volatile acquisition. It was concluded that the method of election for the comparison of large sets of samples from a multi-omics approach consists on flash freezing the biological material with liquid nitrogen at the selected ripening stage and the use of headspace solid phase microextraction coupled to gas chromatography and mass spectrometry for the subsequent analysis. This method was implemented and was used for the determination of volatile compounds in selected NILs harbouring QTLs for characters related to flavour and aroma introgressed in different genetic backgrounds. The results allowed the association of several of the organoleptic characters previously identified with modified levels of several volatiles. It was also observed that the genetic background has a major effect on the production of such metabolites. Correlation analysis between the levels of volatiles and primary metabolites led to the conclusion that the production of volatile compounds is generally not determined by the levels of their precursors. Its regulation is most likely to be due to downstream processes such as the availability of either precursors or intermediate metabolites, the variability in specific processes leading to the concersion of precursors into volatiles, or to other still unknown regulatory mechanisms. Volatile compounds were also studied in a RIL population derived from a cross between Solanum pimpinellifolium accession TO-937, the closest species to cultivated, which produces red fruits, and S. lycopersicum cv. 'Moneymaker', a tomato variety for the fresh market. This allowed the identification of 102 QTLs for 39 different volatile compounds, 76 of which had not been previously described. All these QTLs were mapped along the 12 tomato chromosomes by means of the SOLCAP SNPs molecular market map. Most of the QTLs identified were subsequently evaluated on introgression lines (ILs) generated from the same original genotypes. It was observed that almost half of the QTLs previously identified retained their effect after introgression in the 'Moneymaker' genetic background. Additionally, 12 new QTLs were identified in this IL population. Based on the existing knowledge about the effect of volatile compounds on our perception of flavour and aroma and also on their ability to maintain their effect after introgression in the cultivated tomato, some of the QTLs identified are good candidates to be used in tomato flavour breeding programs. Eventually, the comparison of the localization in the genome of the QTLs identified in the different populations studied with those already described in the literature revealed a very low degree of co-localization between the different QTLs. This implies that there exists a wide range of variability in the wild species related to tomato available for breeding tomato flavour and aroma. / [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. / [CA] 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]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61768 / TESIS / Premios Extraordinarios de tesis doctorales / Compendio

Shrimp is the most valued shellfish product in the United States, and is highly perishable with post mortem metabolic changes that are deteriorative to its shelf-life. The objective of this research was to utilize GC-MS Gas Chromatography-Mass Spectrometry (GC-MS), Gas Chromatography Olfactometry (GCO), and sensory analysis to determine if the relationships exist between consumer acceptability, sensory descriptors and shelf-life of ready-to-eat shrimp. Three different cooking and packaging treatments were utilized: 63°C/15 s, 85°C/5 min, and 93°C/5 min for vacuum, MAP and aerobic packaging treatments, and stored at 2°±1 for 1, 3, 5, 6, 10, 15, 25, and 50 days or until the product was found unacceptable by a trained sensory panel. For Consumer acceptability (Day 3), the 85°C vacuum and 85°C MAP (Modified Atmosphere Packaging) shrimp were preferred (P < 0.05) over other treatments that were evaluated. The aroma active compounds that were identified using GC-MS and GCO consisted of one amine (trimethylamine), five aldehydes (3-methyl butanal, pentanal, hexanal, heptenal, geranial), one organic acid (butyric acid), two sulfur containing compounds (methional, dimethyltrisulfide), one pyrazine (methyl pyrazine) (amine), two alcohols (2-nonen-1-ol, 4 ethyl guaiacol), and one hydrocarbon (camphene). Results showed that for most of the packaging-temperature combinations, even beyond Day 25, the MAP product had fewer compounds and odors associated with spoilage than the aerobic and vacuum packaged products. This was consistent with the descriptive analysis data for which both the 85°C MAP and 93°C MAP treatment products had a longer shelf-life than vacuum treatment products, which had shelf-lives of 15 to 21 Days. The shelf-life of the cooked RTE shrimp that was MAP packaged and cooked at either 85°C or 93°C was between 39 and 42 Days at 2°C. Research indicates that processors of medium gulf brown shrimp could utilize 85°C/5min with MAP due to the shelf-life of the product and the elevated pleasantness scores when compared to the 93°C/5min treatment throughout the shelf-life of the product.

No description available.

Descriptive sensory analysis is essential to understanding how differing varietals, viticultural techniques, enological techniques, vintage, regions, etc. impact the sensory characteristics found in wines. These studies analyzed the sensory impacts of vine age, whole cluster and stem addition influences, the frequency of cap management regimes, and selected fermentation variables, on 2019 Zinfandel, 2020 Syrah, 2020 Tannat, 2020 Cabernet Sauvignon, and 2021 Graciano wines respectively, from the Central Coast of California, USA. The investigation of Old vine Zinfandel indicated that these wines were defined as complex due to the wide variety of descriptors used to characterize them, having high color saturation and long length, while the Young vine wines were described as considerably less aromatically diverse, yet being defined by high intensity wet topsoil and pomegranate aromas. Acknowledging the absence of literature on classifying Californian Tannat, descriptors such as high color saturation, purple hue, cooked blue fruit, violet, raisin, bitterness, and astringency may serve as descriptors to these uncommon wines. Regarding stem addition, Dried stem wines exhibited the highest color saturation, purple hue, and astringency intensities in both the Syrah and Tannat wines. Generally, the Green stem wines were less lifted, however the presence of stems added a sense of freshness. The Whole cluster and Control wines generally opposed each other. With reference to cap management, as punch down (PD) increased, perceptions of the overall astringency, bitterness, and velvety characteristics increased. Concerning the various fermentation variables, dirty (unwashed grapes prior to fermentation) wines were described by the earthy aroma, washed (washed grapes prior to fermentation) wines by the floral aroma, and spontaneous (uninoculated) wines by the fruity aromas; however, fruity was the predominant aroma across most wines.