The Brazilian wines have been improving in the last few years, mainly because: the utilization of better adapted varieties of Vitis vinifera grapes, the expansion to new and different areas for grapes, to better vineyard practices and the use of good and sound enologic techniques. There are practices on vineyard e after harvest that could help to improving the wine quality. The defoliation is an example. This practice consist of taking off the leaves nearby the clusters facing the east side of the vineyard, to promote better illumination and ventilation for the fruit, all aiming to improve grape quality. The use of cold temperature storage of grapes before the crushing is also a common technique which improves the control about the fermentation process and helps to reduce the logistic problems. The aim of this work was to evaluate the effect of partial defoliation on physical-chemistry parameters of Cabernet Sauvignon grapes and wines, and also to evaluate the effect in wines from Cabernet Sauvignon and Chardonnay grapes, kept in cold storage temperatures, produced on the southwest of the state of Rio Grande do Sul, Brazil. The grapes were harvested in 2008, from a commercial vineyard growning in the trellis system. The defoliation intensity was 20% and was done only on the side of the vineyard that receives sun in the morning and when the berry was in the pea-size. After the harvest, half of the grapes was immediatelly crushed and fermented, called Standard , and the other half was stored for four days at 10ºC before crushing and fermentation, called Cold . The musts were fermented in small lots, in triplicate, with temperature control, staying on the skins for eight days in the case of red wines. The majority of the physical-chemistry analyses was done according Ribéreau-Gayon et al. (1976) and Amerine & Ough (1986). Total phenolics was made by the Folin Ciocalteau Method, according Singlenton & Rossi (1965). The defoliation made in Cabernet Sauvignon showed higher values of total phenolic content for grapes (1.073 against 1.283mg EAG.100g-1 fresh skin) and anthocyanins (304 against 410mg malvidin.100g-1 fresh skin). Consequently, the wines from grapes with defoliation result in more color, more anthocyanins (290 against 301mg malvidin.L-1) and more total phenolic (2.564 against 2.951mgEAG.L-1). On the chilled grapes, the treatment Cold had higher values of anthocyanins and phenolic contents on Cabernet Sauvignon grapes and lower values of pH on white and red wines. On the sensory analyses of wines using Paired Comparison Test, althought the majority of the judges had preferred the samples from the treatments with defoliation and Cold , statistically this results are not significant. The conclusion is that the use of partial defoliation and of cold temperature for clusters storage before the crushing and fermentation, might improve wine quality at least in the condition of this work. / Os vinhos brasileiros têm passado por constantes evoluções nos últimos anos, incorporando notáveis melhorias, principalmente devido: à utilização de cultivares de uva Vitis vinifera mais adapatadas, à busca por novas regiões mais aptas ao cultivo da videira, ao uso de práticas eficientes no vinhedo e de adequadas técnicas enológicas. Existem práticas a serem feitas no vinhedo e pós-colheita que podem potencializar a qualidade dos vinhos. A desfolha feita no parreiral é um exemplo. A técnica consiste na retirada das folhas ao redor dos cachos do lado leste, visando aumentar a insolação e aeração para obter-se uvas de qualidade superior. O uso de câmaras frigoríficas visando fazer um resfriamento dos cachos prévio ao esmagamento também é outra prática corriqueira em algumas vinícolas, pois aumenta o domínio do processo de vinificação e contorna problemas logísticos. Os objetivos deste trabalho foram avaliar o efeito da desfolha nos parâmetros físico-químicos de uvas e vinhos Cabernet Sauvignon e o efeito do armazenamento de cachos em câmara fria antes do processamento em vinhos Chardonnay e Cabernet Sauvignon de Dom Pedrito, Campanha, RS. As uvas foram provenientes da safra 2007-2008, de um vinhedo cultivado em espaldeira. A desfolha foi realizada na base dos ramos, com aproximadamente 20% de intensidade, somente no lado leste do parreiral, no estádio fenológico grão-de-ervilha. Após a colheita, metade dos cachos foi processada imediatamente, consistindo nos tratamentos Padrão e a outra metade foi armazenada durante 4 dias em câmara fria a 10ºC, antes do esmagamento, consistindo nos tratamentos Frio . As microvinificações foram feitas em triplicata, sob temperatura controlada, com período de maceração de 8 dias, no caso dos vinhos tintos. A maioria das análises físico-químicas foram feitas conforme Ribéreau-Gayon et al. (1976) e Amerine & Ough (1986). As análises de polifenóis totais foram realizadas segundo o método Folin Ciocalteau, conforme Singleton & Rossi (1965). Os resultados mostraram que a desfolha feita nas uvas Cabernet Sauvignon resultou em maiores valores de polifenóis totais (de 1.073 aumentou para 1.283mg EAG.100g-1 casca fresca) e antocianinas (de 304 aumentou para 410mg malvidina.100g-1 casca fresca). Consequentemente, nos vinhos provenientes de uvas desfoliadas, observou-se também um aumento significativo de cor, antocianinas (de 290 aumentou para 301mg.L-1), e polifenóis totais (de 2.564 aumentou para 2.951mg EAG.L-1). No segundo experimento, o tratamento Frio também ocasionou um aumento significativo no teor de antocianinas e polifenóis totais nas uvas Cabernet Sauvignon, e resultou em vinhos tintos e brancos com pH mais baixos. Na análise sensorial dos vinhos com Teste de Comparação Pareada, a maioria dos julgadores elegeu as amostras dos tratamentos com desfolha e Frio como preferidas. Entretanto, estatisticamente estes resultados não foram significativos. Conclui-se que as práticas da desfolha e do armazenamento de uvas em câmara fria antes do esmagamento, da forma como foi feita neste experimento, podem favorecer a qualidade dos vinhos.

The quality of red wine was evaluated relating the variation of meteorological conditions such as color quantification and phenolic compound. Red wines of the cultivars Vitis vinifera, Cabernet Sauvignon, Merlot and Tannat, of the crops of 2003 and 2004 from the low-land (Santana do Livramento) or high-land (Bento Gonçalves) regions of the state of Rio Grande do Sul were analyzed. The phenolic compounds quantified were total flavonoids, anthocyanic flavonoids, non-anthocyanic flavonoids, total polyphenols, polymerized polyphenols, total anthocyanins and free anthocyanins. For the color were analyzed the color intensity and tonality and the chromatic parameters relative to the color spaces that were calculated from the tristimuli values, X, Y, and Z, based on the visible absorption spectra (400-700 nm) with 10nm of pause, on the illuminant D65 reading. The meteorological data related to the crop seasons of 2003 and 2004 were provided by 'Embrapa Uva e Vinho' (Agro meteorological station) in Bento Gonçalves and by 'Pernod Ricard' Brazil (meteorological station in Santana do Livramento). The wines of the cultivar Tannat of the crops of 2003 and 2004 has a high level of phenolic compounds, color intensity and chromatic parameters, due to the cultivar characteristics of having in its composition high level of anthocyanins, showing the red tint, while the wines of the cultivar Cabernet Sauvignon of the 2003 crop, from both regions has low level of phenolic compounds and low color intensity, showing a ruby tint. The 2004 crop in the low-land and high-land regions shows high level of phenolic compounds and color intensity, due to the climatic conditions favorable, dry, high insulation and with media temperature higher on the grapes maturation period, what provided a more complete maturation, mainly phenolic, while the 2003 crop presented a lot of precipitation and low insulation during the grapes maturation period. / Avaliou-se a qualidade dos vinhos tintos relacionando-os a variação das condições meteorológicas com a quantificação da cor e dos compostos fenólicos. Foram analisados vinhos tintos das variedades Vitis vinifera, Cabernet Sauvignon, Merlot e Tannat, das safras de 2003 e 2004 provenientes da região de Santana do Livramento (Região da Campanha) e de Bento Gonçalves (Serra gaúcha), do Rio Grande do Sul. Os compostos fenólicos quantificados foram os flavonóides totais, flavonóides antociânicos, flavonóides não-antociânicos, polifenóis totais, polifenóis polimerizados, antocianinas totais e antocianinas livres. Quanto à cor, foram analisadas a intensidade e a tonalidade bem como os parâmetros cromáticos relativos aos espaços de cor, calculados a partir de valores triestímulos X,Y,Z, com base nos comprimentos de onda de 400 a 700 nm, em intervalos de 10 nm, nas leituras do iluminante D65. Os dados das condições meteorológicas referentes às safras 2003 e 2004 foram fornecidos pela Estação Agroclimatológica da Embrapa Uva e Vinho, de Bento Gonçalves, e pela Estação Meteorológica da Pernod Ricard Brasil, de Santana do Livramento. Os vinhos da variedade Tannat, das safras de 2003 e 2004, apresentaram maior teor de compostos fenólicos, intensidade de cor e os parâmetros cromáticos, devido às características da variedade de possuírem em sua composição maiores teores de antocianinas, o que indica vinhos de tonalidade vermelha, enquanto que os vinhos da variedade Cabernet Sauvignon da safra 2003 apresentaram, nas duas regiões, menores teores de compostos fenólicos comparados com as outras variedades, com pouco valor de intensidade de cor, indicando uma tonalidade rubi. A safra de 2004, nas regiões de Bento Gonçalves e de Santana do Livramento, apresentaram um maior teor de compostos fenólicos e um elevado índice de intensidade de cor, devido às condições meteorológicas favoráveis, safra seca e ensolarada, com temperatura média do ar mais elevada no período de maturação das uvas, que proporcionaram índices de maturação, principalmente a fenólica, mais completa, enquanto que a safra de 2003 apresentou muita precipitação pluvial e pouca insolação durante o período de maturação das uvas.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2018-02-26T14:04:16Z No. of bitstreams: 1 PGPV16MA197.pdf: 2230923 bytes, checksum: e668d82b2261743e59f2124d9315814d (MD5) / Made available in DSpace on 2018-02-26T14:04:16Z (GMT). No. of bitstreams: 1 PGPV16MA197.pdf: 2230923 bytes, checksum: e668d82b2261743e59f2124d9315814d (MD5) Previous issue date: 2016-07-13 / Capes / Highland regions of Santa Catarina State, Brazil, have been acquiring great importance due to the high potential for wine production from Vitis vinifera L. cultivars, but due to highlands of Santa Catarina State are being in an emergent wine grown region fundamental investigations into vineyard practices are necessary. This work aims to contribute to the generation of data that can direct the management of leaf removal in the vineyards in order to develop a differentiated quality wine, determining times of leaf removal in the varieties Cabernet Sauvignon and Sauvignon Blanc, and evaluate the its effect on vegetative, productive aspects, enological potential of grape wine quality, and the occurrence of bunch rot. The results of this study show the importance of management of leaf removal grapes wines, demonstrating its benefits in relation to technological and phenolic maturity indices, providing better quality grape, higher productivity and better vegetative balance. And the leaf removal, held between phenological full flowering stage and grain pea resulted in a significant reduction in the incidence and severity of bunch rot of Cabernet Sauvignon and Sauvignon Blanc grown in high altitudes of Santa Catarina. It is evident that the removal leaf vine is indispensable for obtaining a grape of high quality and sanity / As regiões de altitude de Santa Catarina vem despertando interesse de investidores, pela sua característica de elaborar vinhos de elevada qualidade. Porém, por ser uma atividade ainda recente nessas regiões, há uma grande demanda pela geração de informações técnicas adequadas, visto que possui características distintas das demais regiões vitícolas do Brasil. A presente dissertação visa contribuir na geração de informações que possam direcionar o manejo da desfolha nos vinhedos, a fim de elaborar um vinho de qualidade diferenciada, determinando o efeito de diferentes épocas de desfolha nas variedades Cabernet Sauvignon e Sauvignon Blanc sobre aspectos vegetativos, produtivos, potencial enológico da uva, qualidade do vinho, e na ocorrência de podridão cinzenta (Botrytis cinerea Pers) nos cachos. Os resultados deste estudo evidenciam a importância do manejo da desfolha da videira, demonstrando seus beneficios em relação aos índices de maturação tecnológica e fenólica, propiciando melhor qualidade da uva, maior produtividade e melhor equilíbrio vegeto:produtivo. Além disso, a realização de uma desfolha precoce, realizada entre os estádios fenológicos plena florada e grão ervilha resultaram em redução da incidência e severidade de podridão cinzenta (Botrytis cinerea) nos cachos das variedades Cabernet Sauvignon e Sauvignon Blanc cultivadas em elevadas altitudes de Santa Catarina. Evidencia-se que o manejo da desfolha da videira é indispensável para obtenção de uma uva de elevada qualidade e sanidade

Made available in DSpace on 2016-12-08T16:44:41Z (GMT). No. of bitstreams: 1 PGPV12MA100.pdf: 870378 bytes, checksum: fe64b515969e81e27b2b9fdf4fe07558 (MD5) Previous issue date: 2012-02-16 / The region of San Joaquin has proved favorable to the production of fine wines and has been gaining entrepreneurial. However, there are many skills needed by those who want a viable cash crop. The practical viticulture is the application of a set of technical management of vineyards, in order to produce the maximum quantity of grape without reducing their enological potential required by certain markets, with minimum cost. These practices derived from scientific knowledge about the biology and physiology of plants in relation to the terroir . One of the main factors that interfere in the for developing a vineyard is the management of the canopy and cultivation techniques, such as cluster thinning. Thi study aimed to learn about the physiological and technological maturity of the clusters of Cabernet Sauvingon grapevines, produced in altitude regions of Santa Catarina State. The vineyard has been submitted to differentes levels of cluster thinning made at the véraison , in order to establish criteria that will help determine the most appropriate management for the preparation of fine red wines in areas above 900 meters in altitude. The experiment was carried during 2009/10 and 2010/11 vintage at the Villa Francioni Vineyards in the city of São Joaquim (28˚ 17 39 S, 49˚ 55 56 W), at altitude of 1230 meters with cv. Cabernet Franc grafted on Paulsen 1103. The levels of cluster thinning, adjusted at the véraison , corresponded to maximum production and percentage reductions in their productivity in 25%, 50% e 75%. From results found it is concluded that in altitude regions the practice of cluster thinning affects the chemical characteristics of the grape and wine cv Cabernet Franc, but there was a siginificant improvement in quality when we see all the parameters involved. Under the conditions of the experiment there was no balance vegetate: productive of plants / A região de São Joaquim tem se mostrado favorável à produção de vinhos finos e vem despertando interesse de empreendedores da atividade. Entretanto, muitos são os conhecimentos demandados por quem deseja viabilizar um cultivo comercial. A vitivinicultura prática otimizada é a aplicação de um conjunto de técnicas de manejo do vinhedo, de modo a produzir a máxima quantidade de uva sem reduzir seu potencial enológico exigido por determinados mercados, com um custo mínimo. Estas práticas derivam do conhecimento científico sobre a biologia e a fisiologia das plantas em relação ao meio em que é cultivado o vinhedo e sua manipulação em qualquer condição ou local. A dificuldade está em identificar o equilíbrio exato entre a produção, vigor e qualidade da uva. Um dos principais fatores que interferem no potencial de desenvolvimento de um vinhedo é o manejo do dossel e as técnicas de cultivo, dentre os quais se encontra o raleio de cachos. O presente trabalho teve como objetivo obter informações sobre a maturação fenólica e tecnólogica dos cachos na cultivar Cabernet Franc, produzidos em região de altitude. O vinhedo foi submetido a diferentes níveis de raleio de cachos realizados na virada de cor, de modo a estabelecer critérios que contribuam para definir o manejo mais apropriado para a elaboração de vinhos tintos finos em regiões acima de 900 metros de altitude. Os ensaios foram conduzidos durante as safras de 2009/10 e 2010/11 em um vinhedo da empresa Villa Francioni Agronegócios S/A, coordenadas 28˚ 17 39 S e 49˚ 55 56 W, a 1230 metros de altitude , localizado no município de São Joaquim, SC. O talhão utilizado da cultivar Cabernet Franc foi enxertadas sobre Paulsen 1103 consuzido em espaldeira, com espaçamento de 3,0m x 1,2m e cobertura anti-granizo. Os níveis de raleio de cachos, ajustados na virada de cor véraison , corresponderam a produção máxima, e reduções percentuais em sua produtividade em 25%, 50% e 75%. Dos resultados obtidos conclui-se que em condições de altitude, a prática de raleio de cachos afeta as características químicas da uva e do vinho cv Cabernet Franc, porém não houve uma melhora significativa na qualidade quando se verifica todas as características envolvidas. Nas condições do ensaio não se observou equilíbrio vegetativo:produtivo das plantas

Made available in DSpace on 2015-05-14T13:21:45Z (GMT). No. of bitstreams: 1 parte1.pdf: 2505729 bytes, checksum: e872a92484e063cf1f264ba7b16d9e2e (MD5) Previous issue date: 2010-03-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work proposes the use of digital images captured by a Webcam for determination of total acidity in red wines by means of an acid-base titration without using an external indicator. Digital images present the colour of the emergent radiation, which is complementary to the radiation absorbed by molecules of anthocyanines presents in wines. Each image, generated according to RGB system, yields a matrix of the values of the R, G and B components whose averages define a the colour value obtained as: 2R ⋅2G ⋅2B. This value was adopted as analytical response to build titrations curves based on digital images (DIB). For a more precise localization of the end point, titrations curves were generated on the basis of the second derivative values of the analytical response. Anthocyanines present different colours according to medium pH and, from the variation of the colour values of the images obtained during the titration of the red wines, the end point could be detected with precision. The official method recommends the use of potenciometric titration for determination of total acidity in red wines. This method requires a dilution of the sample before the titration that must be carried out until a fixed value of pH (8.2 8.4). In order to illustrate the feasibility of the proposed method titrations involving the determination of total acidity in ten red wines samples were carried out. Results were compared to the ones obtained by potenciometric titration used as reference method. No statistic difference has been observed between the results by applying the paired t-test at 95% confidence level. The proposed method yielded results with a better precision than the official method. These advantageous characteristics are attributed to the trivariate nature of the measures associated to digital images. / Neste trabalho, propõe-se o uso de imagens digitais, capturadas com uma Webcam, para determinação da acidez total de vinhos tintos por meio de titulação ácido-base sem a utilização de indicador externo. As imagens digitais apresentam a cor da radiação emergente que é complementar à da radiação absorvida por moléculas de antocianinas presentes nos vinhos. Cada imagem, gerada de acordo com o sistema vermelho-verde-azul (RGB), fornece uma matriz de valores dos componentes R, G e B cujas médias definem o valor de cor obtido como: 2R ⋅2G ⋅2B. Esse valor foi adotado como resposta analítica para a construção das curvas de titulação baseadas em imagens digitais (DIB). Para a localização mais precisa do ponto final, foram geradas as curvas de titulação com base nos valores da segunda derivada da resposta analítica. As antocianinas apresentam diferentes cores de acordo com o pH do meio e, a partir das variações do valor de cor das imagens obtidas durante a titulação dos vinhos tintos, o ponto final pôde ser detectado com precisão. O método oficial recomenda o uso da titulação potenciométrica para a determinação da acidez total de vinhos tintos. Este método requer diluição da amostra antes da titulação que deve ser efetuada até um valor fixo de pH (8,2-8,4). A fim de ilustrar a viabilidade do método proposto, foram realizadas titulações envolvendo a determinação da acidez total em dez amostras de vinhos tintos. Os resultados foram comparados com os obtidos pela titulação potenciométrica usada como método de referência. Constatou-se que não há diferença sistemática estatisticamente significativa entre os resultados, aplicando-se o teste t emparelhado ao nível de 95% de confiança. O método proposto produziu resultados com uma precisão melhor que a do método oficial. Essas características vantajosas da titulação DIB são atribuídas à natureza trivariada das medidas associadas às imagens digitais.

Tout au long du procédé d’élaboration d’un vin, des réactions d’oxydation peuvent se produire y compris au cours du vieillissement en bouteilles. Depuis quelques années, la profession viti-vinicole est confrontée au problème de l’oxydation prématurée des vins blancs.. A ce jour, peu d’études ont pu apporter des explications d’ordre chimique à ce phénomène, et les mécanismes réactionnels intervenant restent peu connus.L’objectif de ce travail de thèse est d’apporter, au travers d’une analyse moléculaire non ciblée en spectrométrie de masse à transformée de Fourier et à résonance cyclotronique des ions (FT-ICR-MS) couplée à une étude chimiométrique, des réponses originales aux questions posées par la problématique actuelle d’oxydation prématurée des vins blancs. Nous avons montré suite à l’étude d’une série de vins oxydés prématurément non seulement la grande diversité chimique des vins, mais aussi la présence d’un ensemble de masses typiques associées à ce phénomène. Pour une meilleure compréhension de l’origine de cette problématique, nous avons considéré deux autres types d’oxydation : une oxydation relative exclusivement à un apport contrôlé en oxygène et une autre relative à l'évolution naturelle de vins en bouteilles. Cette dernière consiste en le suivi de l'évolution des espaces chimiques de séries verticales de vins blancs et rouges en fonction du temps. Sur la série verticale des vins blancs allant de 1979 à 2006, une charnière à l’année 1990 a été observée avec des groupes de masses typiques de chacun des vins jeunes (1979-1990) et des vieux vins (1991-2006).La comparaison entre les espaces chimiques discriminants chacun de ces trois types d’oxydation ne révèle la présence que de trois masses en commun, ce qui appuie l'hypothèse de causes multiparamétriques à l’oxydation prématurée des vins blancs, qui ne serait donc pas un phénomène du exclusivement à une exposition non contrôlée à l'oxygène.Des essais d’élucidation structurale en FT-ICR-MS/MS des masses discriminantes des vins oxydés et de la série verticale ont été effectués et des schémas de fragmentation pour certaines masses sont proposés / During winemaking processes, many oxidation reactions may occur especially during the aging period. Recently, white wines are characterized by a problem of premature oxidation for which few studies have provided chemical explanation. To date, the involved mechanisms in this phenomenon remain poorly understood.The aim of this thesis project is to provide, through an untargeted molecular analysis using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) coupled to chemometric analysis, original clue to understand the premature oxidation of white wines. Based on the study of a series of premature oxidized white wines, we were able to elucidate the high complexity and the chemical diversity of wine, and got out typical masses characterizing the oxidation state. In order to better understand the origin of this phenomenon, we considered two alternative possibilities of oxidation: the first one induced by oxygen, and the second through a natural evolution of wines in bottles. The latter included the monitoring of the chemical evolution of white and red wines as a function of time. A very interesting result was obtained on the vertical series of white wines from 1979 to 2006, where two groups were separated at the 1990 vintage to provide a group of old wines (1979-1990) and a group of new wines (1991-2006). Typical discriminant masses were found for each group.A comparison between the chemical spaces discriminating each of the three types of oxidation (premature oxidation, oxidation with oxygen and natural evolution of wine in bottle) revealed very few common masses that may indicate that the phenomenon of premature oxidation is indeed influenced by multiple factors.Finally, a structural elucidation of the typical masses of the groups of oxidized and aged wines were established using FT-ICR-MS/MS. Possible fragmentations schemes of some of these masses were proposed

La famille aromatique du végétal dans les vins rouges recouvre une large diversité de nuances. Nos travaux révèlent que celles-ci n’ont pas toujours de lien direct avec les composés connus (2-méthoxy-3-alkylpyrazines, alcools en C6). Aussi, après avoir été définis sensoriellement, les déterminants moléculaires de cette famille d’odeurs ont été recherchés en s’appuyant, à partir de vins représentatifs, sur différentes techniques de fractionnement (CLHP, distillation sous vide) puis MDCPG-O-SM. Une première origine de ces nuances a été développée, celle associée à la maturité des raisins. La présence du 1,8-cinéole (eucalyptol), avec des notes « vertes », selon une origine variétale en lien avec la maturité des raisins a pu être attestée dans les vins de Cabernet Sauvignon. La capacité d’un cépage à en produire des quantités significatives (Fer Servadou) ainsi qu’une origine exogène associée à la présence d’une espèce d’armoise au vignoble (Artemisia verlotiorum) sont aussi établis. Une autre origine d’apparition des nuances végétales a été considérée : le pressurage des marcs. Cette étude montre le lien étroit entre la catégorie aromatique des vins de presse et la famille du végétal. En outre, elle révèle la présence de divers marqueurs odoriférants, en particulier le (Z)-4-heptenol dont l’évolution est corrélée au niveau de pression et la contribution sensorielle établie, à l’inverse de la plupart des alcools en C6 ; de même qu’elle suggère l’implication de plusieurs composés carbonylés à l’odeur caractéristique des vins de presse. L’influence des paramètres technologiques (inertage, pression, SO2, FML) est aussi précisée. La présence du salicylate de méthyle comme marqueur de défense de la plante contre plusieurs maladies cryptogamiques (mildiou, black rot, esca) et comme contributeur à l’odeur végétale de certains vins rouges a enfin pu être démontrée. / The green aromas family includes in red wines a large diversity of nuances. First, this study revealed that these nuances are not directly related to known compounds (e.g. 2-méthoxy-3-alkylpyrazines, C6 alcohols). After a sensory definition, the molecular determinants of these aroma nuances were investigated based on fractionation strategies including HPLC and vacuum distillation then MDGC-O-MS. A first source of nuances associated with grapes ripeness was developed. The presence of 1,8-cineole (eucalyptol) with a varietal origin was evidenced in Cabernet Sauvignon wines. The ability of a grape variety to produce significant amounts (Fer Servadou) and an exogenous origin associated with the presence of Artemisia species in vineyards (Artemisia verlotiorum) were also highlighted. Another origin, related to the pressing of grape marc was then considered. This study shown the connection between the aromatic category of press wines and the green aromas. Furthermore, it revealed the presence of odoriferous molecules including (Z)-4-heptenol, with a sensory contribution, associated to the increase of pressure in the press tank, but not for the majority of C6 alcohols. It also suggested the involvement of several carbonyl compounds in the characteristic odor of press wines. The influence of technological parameters (without oxygen, pressure, SO2, malolactic fermentation) was also specified. Finally, this study revealed the presence of methyl salicylate as a plant defense marker against several fungal diseases (downy mildew, black rot, esca) and as a contributor to fresh green aromas of certain red wines.

The present thesis deals with the establishment of a small business. It focuses more specifically on a business oriented on French wines and specialities. The theoretical part deals with the general explanation of concepts such as entrepreneur and small business, theory of business plan, collection and analysis of market-connected data. The analytical part includes research in the form of questionnaire with the aim of discovering customers´ preferences in the gastronomical market. The analytical part contains further analysis according to Porter, SLEPT analysis and SWOT analysis. The practical part focuses on the business plan of the small business with all its requirements.

Thesis (PhD (Viticulture and Oenology. Wine Biotechnology))--Stellenbosch University, 2008. / Although bananas are widely grown worldwide in many tropical and a few subtropical countries, banana beverages are still among the fruit beverages processed by use of rudimentary methods such as the use of feet or/and spear grass to extract juice. Because banana juice and beer remained on a home made basis, there is a research drive to come up with modern technologies to more effectively process bananas and to make acceptable banana juices and wines. One of the main hindrances in the production of highly desirable beverages is the pectinaceous nature of the banana fruit, which makes juice extraction and clarification very difficult. Commercial enzyme applications seem to be the major way forward in solving processing problems in order to improve banana juice and wine quality. The particular pectinolytic enzymes that were selected for this study are Rapidase CB, Rapidase TF, Rapidase X-press and OE-Lallzyme. In addition this study, investigate the applicability of recombinant yeast strains with pectinolytic, xylanolytic, glucanolytic and amylolytic activities in degrading the banana polysaccharides (pectin, xylan, glucan starch) for juice and wine extraction and product clarification. The overall objective of this research was to improve banana juice and wine by enzymatic processing techniques and to improve alcoholic fermentation and to produce limpid and shelf-stable products of clarified juice and wine. The focus was on applying the selected commercial enzyme preparations specifically for the production of better clarified banana juice and wine. This is because the turbid banana juice and beer, which contain suspended solids that are characterised by a very intense banana flavour, require a holistic approach to address challenges and opportunities in order to process pure banana beverages with desirable organoleptic qualities. The specific objectives of applying commercial enzymes in the processing of banana juice and wine, comparing with grape winemaking practices, use of recombinant yeast and analyses of various parameters in the juices and wines made have enabled generation of information that could be of help to prospective banana juice and wine processors. The research findings obtained could be used to establish a pilot plant or small-scale industry in the banana processing beverages producing large quantities,and finally the overall objective of obtaining limpid and shelf stable products would be achieved.

La Valle d'Aosta, pur non avendo grandi superfici destinate alla viticoltura, è caratterizzata dalla presenza di un ricco patrimonio ampelografico di cui fanno parte dodici varietà autoctone a bacca rossa: Bonda, Cornalin, Crovassa, Fumin, Mayolet, Ner d'Ala, Petit rouge, Premetta, Roussin, Roussin de Morgex, Vien de Nus e Vuillermin. Malgrado i numerosi vitigni menzionati, nella produzione dei vini a D.O.C troviamo in prevalenza il Petit rouge e poche altre varietà che, nell'insieme, rappresentano circa il 34% della produzione totale. Al fine di implementare la presenza di prodotti tipici che esprimano i caratteri distintivi della zona di provenienza sono state approfondite le conoscenze dei vitigni autoctoni per evidenziarne le attitudini e le potenzialità per la produzione di vini rossi di qualità. Allo stesso scopo sono stati valutati gli effetti dell'applicazione di alcune tecniche di vinificazione alternative sull'espressione dei caratteri qualitativi del Petit rouge, le cui uve sono da tempo vinificate in purezza o in assemblaggi nella produzione di vini a D.O.C. / Aosta Valley has a little viticulture surface and it is characterised by a rich ampelographic collection including the following twelve red grape autochthonous varieties: Bonda, Cornalin, Crovassa, Fumin, Mayolet, Ner d'Ala, Petit rouge, Premetta, Roussin, Roussin de Morgex, Vien de Nus e Vuillermin. Only the 34% of the D.O.C. wine production is represented by some of the above mentioned cultivars, in particular the Petit Rouge, despite of the huge number of cultivars. The Petit rouge is used in purity or in miscellaneous in the D.O.C. wine production. In order to implement the presence of typical products, this study was carried out to evaluate the aptitude of Aosta Valley ancient grapes to produce quality red wines. Moreover to improve quality of the most diffused Aosta Valley red wine the effects of some alternative winemaking were evaluated on the Petit rouge characters.