Memoria para optar al Título Profesional de Ingeniero Agrónomo Mención: Enología y Viticultura / La industria enológica, permanentemente desarrolla nuevos productos que buscan mejorar las características técnicas y organolépticas de los vinos elaborados. La decisión de uso debe equilibrar variables técnicas y económicas junto a la búsqueda de atributos de calidad reconocibles y valorables por el consumidor. En este trabajo se comparó el efecto de dos levaduras sobre las características físicas, químicas y sensoriales de un vino Chardonnay obtenido con diferentes formas de nutrición nitrogenada. Para ello, se utilizó un mosto deficiente en nitrógeno asimilable al que se adicionó nitrógeno inorgánico (sal de amonio) y un suplemento nutritivo complejo. Durante la fermentación alcohólica, mediante registros diarios de densidad, temperatura y conteos poblacionales de levaduras viables, se evaluó el comportamiento de las cepas utilizadas y se comprobó, que la velocidad y duración del proceso fermentativo, es diferente independiente del tipo de nutrición utilizada. Los vinos fueron analizados físico químicamente y se comprobó que las diferencias obtenidas por efecto de las cepas de levaduras o por el tipo de nutrición nitrogenada, no comprometen analíticamente al producto final. Sensorialmente, las cepas estudiadas presentaron diferencias cuantitativas y/o cualitativas respecto a atributos como intensidad aromática, aromas a frutos tropicales y aceptabilidad, mientras que el uso de un suplemento nutritivo complejo, generó diferencias en la percepción del panel de estos y otros atributos, como la persistencia, acidez y amargor. Se pudo comprobar que el perfil aromático específico presentó diferencias por acción de la cepa de levadura utilizada, pero una suplementación compleja, no generó diferencias en tipo, cantidad e intensidad de descriptores aromáticos identificables por el panel. / The wine industry, constantly develop new products to improve the technical and organoleptic characteristics of wines produced. The decision of use, must balance technical and economic variables beside obtaining appreciated quality attributes by the consumer. In this study, the analytical and sensory effect of wine obtained with two yeasts and different forms of nitrogen nutrition, using a Chardonnay grape juice, deficient in this element was compared Through daily records of density, temperature and counts of viable population it was demonstrated that the breeds of yeast respond differently on the rate fermentation and duration of the process regardless of the type of nitrogen nutrition. The analytical differences obtained, product of the effect of the yeast breeds or the type of nitrogen nutrition, does not compromise final parameters of wine. The studied breeds showed quantitative and/or qualitative sensorial differences especially on aromatic intensity, aromas of tropical fruits and acceptability. The use of a complex nutritional supplement made differences in the perception of the panel of these and other attributes, such as persistence, acidity and bitterness. The aromatics profiles due the actions of yeast breeds were different, however a complex supplementation were not generated differences on quantity and intensity of aromatics descriptors recognizable by the panel.

Memoria para optar al Título Profesional de Ingeniero Agrónomo Mención Enología y Vitivinicultura / En el presente estudio se evaluó el efecto de la criomaceración y diferentes fechas de cosecha sobre la composición fenólica, características químicas y sensoriales de los vinos de los cultivares Cabernet Sauvignon y Chardonnay. Se utilizaron uvas provenientes del Valle del Maipo cosechadas durante la vendimia 2003, las cuales fueron sometidas a criomaceración durante 10 días para su posterior vinificación. A la materia prima de cada uno de los tratamientos, se les realizó análisis básicos determinándo, entre otros, densidad, pH y acidez. Durante el período que duró la criomaceración y la fermentación alcohólica se realizaron diariamente análisis de compuestos fenólicos tales como fenoles totales, intensidad colorante, taninos totales y, en el caso de los tratamientos de la cepa Cabernet Sauvignon, antocianos totales. Al término de la vinificación y luego de darles 2 meses de reposo en botella, a los vinos resultantes se les realizaron los mismos análisis de compuestos fenólicos además de grado de polimerización de taninos y los índices de etanol y gelatina. Para la determinación de compuestos fenólicos de bajo peso molecular y antocianos se utilizó un equipo de cromatografía líquida de alta eficiencia acoplado a un detector de fotodiodos alineados (HPLC-DAD).

El objetivo de este trabajo es caracterizar los compuestos volátiles responsables del aroma del vino elaborado a partir de la variedad Chardonnay, independientemente del origen geográfico y del estilo de vinificación. En una primera experiencia, la tipicidad « Chardonnay » de un grupo de 48 vinos (de los cuales 29 eran Chardonnay y 19 no) fue evaluada por un panel de expertos. Este estudio permitió la selección de un sub-grupo de vinos pertenecientes a dos niveles de tipicidad distintos: buenos ejemplos y malos ejemplos de vino Chardonnay. La segunda étapa del estudio consistió en seleccionar un método de extracción que diera lugar a un extracto representativo del aroma del vino de Chardonnay. Se evaluaron tres métodos de extractión: la extracción con diclorometano, el "salting-out" seguido de una destilación a vacio y el "salting-out" seguido de una extracción con diclorometano. Los extractos obtenidos fueron re-diluidos en una solución hidroalcohólica (12% vol.) para su comparacion sensorial con el vino original mediante un test de similitud. Los resultados mostraron diferencias significativas entre los tres métodos de extracción. El método de extración con diclorometano fue seleccionado por su buena compatibilidad con la cromatografia en fase gaseosa y por su facilidad de realización. Durante la tercera etapa se llevó a cabo una selección de los miembros del panel de olfactometria. Cuatro tests sirvieron para evaluar la habilidad de los candidatos a describir los olores, su repetibilidad en la deteccion y en la descripción, así como la presencia de hiposmias. Estos tests permitieron seleccionar 17 personas de entre 29 candidatos. La etapa sigiente consistió en el análisis olfactométrico propiamente dicho. Los 18 vinos elegidos fueron analizados por los 17 evaluadores seleccionados según el método de las frecuencias de detección. Setenta y dos zonas de olor fueron definidas. Gracias a una regresion PLS, se encontro una relación entre las notas de tipi / Ballester Pérez, J. (2004). Mise en évidence d'un espace sensoriel et caractérisation des marqueurs relatifs à l'arôme des vins issus du cépage Chardonnay [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1850 / Palancia

The diploma thesis deals with the influence of spontaneous and controlled technology on the creation of biogenic amines. In the literary part, it deals with the properties, origin and their occurrence. It further describes the various factors and microorganisms that influence their creation. Consequently, it focuses on the effect of biogenic amines on health and factors that may increase their toxicity in the microorganism. At the end of the literature search, describe focuses on the creation of biogenic amines in wine, their content in world wines and focuses on oenological factors affecting their content. The experimental part describes the Chardonnay experiment procedure in detail. It was divided into four variants. Two of them were technologically processed in the barrel, the other two in a glass container. Subsequently, both versions in the barrel and in the glass were divided into a production process processed by spontaneous and controlled technology. Samples were sampled during the experiment and then analyzed analytically by HPLC for the formation of biogenic amines. The resulting wines were sensory evaluated. All results were statistically processed and compared with studies dealing with similar issues.

A field study was conducted in 1991 to determine whether high rates of cap retention in 'Chardonnay' grapes contributed to increased levels of Botrytis bunch rot (<i>Botrytis cinerea</i> Pers.), and whether spreader-sticker application enhanced cap retention. At bloom, the sticker Nu-Film 17®, or water (control), was sprayed onto single clusters at diluted ( 0.63 ml/ L ) and concentrated ( 1.26 ml/L ) label rates. After fruit set, some clusters were cleaned of caps and other flower parts with pressurized air. Cap and debris retention, berry scarring, and Botrytis rot were evaluated throughout the season. The spreader-sticker application increased debris retention only slightly. Removal of caps and debris had no effect on scarring, but reduced Botrytis bunch rot. The role of flower thrips <i>Frankliniella tritici</i> (Fitch) in causing scarring and in increasing Botrytis rot in Chardonnay grapes was explored in 1992. The insecticide methomyl (Lannate®) at a labeled rate (0.9 ml per 377 ml water per vine), or water (control), was sprayed onto selected vines twice at bloom. Berry scarring and Botrytis bunch rot were evaluated at mid-season and at harvest. The insecticide treatment reduced scarring, but did not affect Botrytis rot incidence. A survey of Virginia grape growers was conducted for 1990 and 1991, to collect information on pest and disease severity and chemical and non-chemical pest control methods. In growers’ opinions, black rot, Japanese beetle, and annual grasses were the most severe disease, insect, and weed problems respectively. Pesticides most commonly used were captan, glyphosate, and carbaryl. / Master of Science

L'objectif premier de ce travail de thèse était de développer des analyses métabolomiques non ciblées de vins en bouteilles afin de déchiffrer les informations chimiques relatives à l’évolution de leurs compositions avec le temps. Cette recherche initiale était fondée sur l'hypothèse que, lors de l'analyse, les vins en bouteilles gardent une mémoire chimique des paramètres environnementaux à l’œuvre au moment de leur élaboration (gestion du vignoble, pratiques œnologiques, climat, terroir). Une seconde hypothèse reposait sur la nécessité d’étudier le passé pour anticiper l’évolution de la qualité du vin du point de vue de sa composition chimique. À cet effet et pour la première fois dans la science du vin, la Spectrométrie de Masse à Résonance Cyclotronique des Ions et à Transformée de Fourier (FTICR-MS), la Chromatographie Liquide couplée à la Spectrométrie de Masse (UPLC-Q-TOF-MS), la spectroscopie de Fluorescence d’Excitation et d’Émission (EEMF) et les statistiques multivariées ont été combinées. Le développement méthodologique a révélé l'avantage de coupler les mesures de masses exactes par FTICR-MS à la discrimination des isomères par UPLC-Q-TOF-MS afin d'étendre la gamme des métabolites détectables. Ces outils ont été appliqués à l'identification de marqueurs de vieillissement sur des séries verticales de vins rouges et blancs de Bourgogne, y compris sur des vins très anciens (millésimes inconnus) considérés comme des points extrêmes d'évolution, introduisant ainsi la notion de verticalomics. La caractérisation d'une série de vins blancs de Bourgogne (Chardonnay) a révélé que les espaces chimiques spécifiquement liés à des pratiques œnologiques (SO2 ajouté lors du pressurage, niveau de débourbage ou perméabilité du bouchon) pourraient être déchiffrés, bien que les signatures de millésimes étaient les plus significatives. Des expériences similaires sur les vins de Champagne (Chardonnay, et mélanges de Chardonnay, Pinot noir et Pinot Meunier) après la prise de mousse et le vieillissement sur lattes ont mis en évidence l'effet d'hormesis associé à l'oxygénation du vin. Enfin, les analyses non ciblées d'extraits de raisin et des vins correspondants provenant de différentes appellations et élaborés par le même vigneron ont révélé qu’il était possible de lire des signatures liées au terroir, en particulier après quelques années de vieillissement en bouteille. Plus largement, nos résultats fournissent une description globale sans précédent de la composition chimique du vin et de sa modification par le vieillissement. / The main objective of this work was to develop non-targeted metabolomics analyses of bottled wines in order to decipher chemical informations from the time-related evolution of their composition. This original research was based on the hypothesis that, when analyzed, bottled wines would still hold chemical memories of envionmental parameters (vineyard management, oenological practices, climate, terroir…) at the moment of their elaboration, even after several years of ageing. A second hypothesis was that in order to anticipate the future evolution of the wine quality in terms of chemical composition, it is necessary to know what it was in the past. To that purpose, and for the first time in wine science, Fourier Transform Ion Cyclotron Resonance – Mass Spectrometry (FTICR-MS), Liquid Chromatography coupled with mass spectrometry (UPLC-Q-ToF-MS), Excitation Emission Matrix Fluorescence (EEMF) and multivariate statistics were used in combination. Methodological develoments revealed the advantage of coupling exact mass measurements by FTICR-MS to isomeric discrimination by UPLC-Q-ToF-MS in order to extend the range of detectable metabolites. Such tools were applied to the identification of ageing markers in vertical series of red and white wines from Burgundy, including very old wines (unknown vintages) considered as evolution end points, thus introducing the concept of verticalomics. The characterization of series of white wines from Burgundy (Chardonnay) revealed that chemical spaces specifically related to eonological practices (SO2 addition at pressing, settling level, and permeability of the stopper) could indeed be deciphered although the vintage signatures were confirmed to be the most significant. Similar experiments on Champagne wines (Chardonnay, and blends of Chardonnay, Pinot noir and Pinot Meunier) after the "prise de mousse" and the ageing "sur lattes" further highlighted the hormesis effect associated with the oxygenation of wine. Finally, non-targeted analyses of series of grape extracts and corresponding wines from different appelations – though elaborated by the same winemaker – revealed that terroir-related signatures could be indeed read in wines, in particular after a few years of bottle ageing. Altogether our results provide an unprecedented comprehensive description of the chemical composition of wine and its modification through ageing.

Fermentation of the grape must into wine is one of the most important steps in winemaking. Selected yeast strains of Saccharomyces cerevisiae have been used for many years to ensure complete and even fermentations. The formation of volatile compounds also occurs during fermentation and will influence the sensory perception of the wine. The main objective of the research was to study the sensory and chemical composition of 1992 Oregon Riesling, Chardonnay and Pinot Noir wines fermented with different commercial S.cerevisiae strains. In the first study, Free-Choice Profiling was used to study the sensory profiles of all three varieties after 7 and 20 months of aging. This method was used in order to utilize a panel of expert winemakers for the tastings. The sensory data analyzed through Generalized Procrustes Analysis showed that some strains were similar while others were different in terms of aroma and flavor at 7 months of age. After 20 months of aging, differences and similarities were still present although the sensory profiles were different from the young wines. This last finding showed that differences are still present after a period of aging. In the second study, the chemical composition of all three varieties and the volatile composition of selected wines of Riesling and Chardonnay were studied. In both white varieties, statistical differences in titratable acidity, residual sugar, volatile acidity and malate content resulted from fermentation with different yeast strains. The volatile composition was qualitatively similar, but some quantitative differences, as relative concentration, were found. Whether or not those differences had a sensory impact was not investigated. Results of the present study showed the need for further studies in order to understand the role of yeast in flavor development. Relationships between sensory profiles and volatile composition could help winemakers to understand the influence of a selected strain on a particular variety and to select yeast strains to optimize wine quality. / Graduation date: 1995

The thesis deals with the occurrence of viral pathogens on grape - Chardonnay clones. Monitored and evaluated clones were 8, 95, 96 (foreign) on rootstocks 1103 Paulsen, SO4, Kober 5 BB and 110 Richter and VP-155/6-VP 161/6, PO-158/7 and PO-160 / 1 (Czech) on the rootstock Kober 5 BB. All plants have a controlled origin. The experiment was conducted in 2013 on the test sites in the cadastral Perná. At the beginning of vegetation were recorded values on 1 herbaceous plant -- sprouting and not-sprouting buds. During vegetation were the plants observed. From the monitored plants were harvested grapes and following parameters were checked: number and weight of the grapes, weight of berries and the stem. Furthermore, before leaf the leaves were sampled for subsequent ELISA test for viral diseases Grapevine fanleaf virus, Arabis mosaic virus, Grapevine fleck virus, Grapevine leafroll-associated virus 1 and 3, Grapevine virus A. All values were evaluated by statistical program Statistica 10.

Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosch, 2011. / Includes bibliography. / ABSTRACT: The grapevine must constantly find a balance between two continually changing environments, the rhizosphere (i.e. soil) and the troposphere (i.e. macroclimate). The adaptations are extremely complex because they encompass complicated and interrelated processes that are not yet fully understood. In terms of water-use behaviour, differences between cultivars have been described in the literature. In this study, the water status and stomatal conductance of four cultivars (Shiraz, Grenache, Pinot noir and Chardonnay) grafted onto R99 were studied. Diurnal cycles of water status and stomatal conductance, from 07:00 to 19:00, were followed for a single day at the end of the 2009 season. The results showed that, at the end of the season, Shiraz was subjected to water stress conditions, losing leaves and showing symptoms of berry shrivelling. The other three cultivars had a much better canopy status and no symptoms of berry shrivelling were observed. Based on the canopy observations and a comparison of the curves of stem water potential (Ψs) and stomatal conductance (gs), it seems that Pinot noir and Chardonnay are closer to the water-use behaviour of Grenache noir, which is known as a “pessimistic” cultivar, than to Shiraz, which is an “optimistic” cultivar. A study of four plots each of Chardonnay/101.14 Mgt and Shiraz/101.14 Mgt was carried out in eight commercial vineyards in the Robertson region in order to investigate the relationship between soil and root morphology, and the influence thereof on canopy development and berry growth. These plots had different soil types. Important soil properties are reported to limit root growth, individually or as a combination of restrictions. It was found that the size of the root system of 101.14 Mgt is defined by soil physical and chemical properties. The roots of 101.14 Mgt under irrigation can grow to a depth of 100 cm or beyond if the soil physical and chemical properties allow it. Because the soil properties define the root system and the water storage/drainage, they greatly influence the plant water status, even under irrigation. In an arid zone like Robertson, irrigation is an important management tool. The balance between canopy growth before véraison and the ability of the root-soil system to maintain that canopy size during the ripening process is crucial in an area with a high evaporative demand. In this regard, not all the soil properties-root system combinations showed satisfactory performance in maintaining the canopy functioning, which affected berry sugar loading and berry volume. In another study that is presented, forty soil profiles were characterised in the Robertson valley. The root systems were considered as a product of the soil properties, and thus the morphology of the root systems was used as a starting point to group soils together. The importance of soil depth has been described well, thus the root systems were first classified according to rooting depth – into shallow and deep root systems. The deep root systems were then subdivided, creating two subgroups of high root density and low root density. The two extreme groups (i.e. shallow roots, and deep roots with high root density) have particularly different soil properties. The soil characteristics found in these extremes are represented up to certain point by families of the South African soil taxonomy, mainly due to the restrictive function of the B horizon. This restrictive function is related to soil properties that are taken into consideration in the South African soil classification and that are important for grapevine root growth, as well as the thickness of the described horizons and the physical and chemical differences between the horizons. Soil properties have an important influence on root morphology. Due to the fundamental role played by the root system in the overall plant functioning, soil properties are of critical importance. In an arid area, the low water pressure in the atmosphere and the high temperature greatly affect the plant water status. The soil-root system combination plays an important role in the ability of the root system to supply the plant with water during times of high evaporative demand. Different cultivars will react differently due to differences in transpiration control. The maintenance of an adequate water status will have an immense influence on canopy development and maintenance, and on normal and steady berry ripening. In this study it was found that not all the soil-root combinations can fulfil this satisfactorily. Thus, the grapevine balance determined by the combination of the soil-root-canopy complex and the influence of management techniques is extremely important for the favouring of a good canopy:root system ratio, a functional canopy throughout the season and a steady berry ripening curve.