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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Compostos fenólicos em uvas e vinhos da variedade Merlot / Phenolic compounds in Merlot grapes and wines

Fogaça, Aline de Oliveira 23 April 2012 (has links)
The main aim of this work was to evaluate the phenolic compounds of Merlot grapes and wines, from vineyards located at Dom Pedrito (Campanha Gaúcha) and Bento Gonçalves (Serra Gaúcha). The following aspects were evalueted: fenolic and industrial ripeness; correlation between the grapes phenolic potencial and the wine phenolics; changes in phenolic compounds during the aging of the wines; impacto of maceration time of wine phenolic composition. The study was conducted for three years: 2009, 2010 and 2011. After grape ripeness evaluations, grape samples were harvested, crushed and fermented , with three different maceration techniques. The phenolic composition of the wines were analyzed after bottling and during aging. The vineyard localization have a great influence on Merlot wine phenolic composition; the grape characteristics was most important than maceration techniques to the wine composition. Important differences, among this two regions, have been found in the content and in the composition of phenolic compounds in the grapes and wines. Dom Pedrito grapes achieved a good cellular maturity, however, when compared with Bento Gonçalves grapes, the anthocyanin content is lower and the quantity of seeds tannins are higher than 50%. The phenolic potential allowed to estimate the total phenolic content, color due polymeric anthocyanins and procyanidin content of Merlot wines. Extended maceration (15 days) are recommended to Dom Pedrito grapes, however it is observed an increase in the pH value; the total crushing of grapes or not will not influence this aspect. During the aging, the results are dependent of vineyard location; Dom Pedrito wines showed a greater polimerization velocity and the differences among maceration times decreased for all wines studied. The main differences among wines from this two regions were color intensity, anthocyanin content, color due polymeric anthocyanin and total phenolic conten of the wines. These facts allows to state that Merlot wines from Serra Gaúcha could be aging for a periodo greater than Campanha Gaúcha wines. / O objetivo principal deste trabalho foi realizar um estudo dos compostos fenólicos em uvas e vinhos da variedade tinta Vitis vinifera Merlot, cultivadas em vinhedos dos município de Dom Pedrito (região da Campanha Gaúcha) e de Bento Gonçalves (região da Serra Gaúcha). Para tanto os seguintes aspectos foram avaliados: maturação fenólica e industrial de uvas amostradas; correlação entre o potencial fenólico estimado nas uvas com a composição fenólica e a cor dos vinhos resultantes; mudanças nos teores de compostos fenólicos dos vinhos elaborados e efeito do tipo de maceração sobre os compostos fenólicos dos vinhos. O estudo foi realizado por três safras: 2009, 2010 e 2011. Após a análise da maturação fenólica e industrial, amostras destas uvas foram vinificadas em pequena escala, com diferentes técnicas de maceração. Os vinhos foram analisados após o engarrafamento e durante o envelhecimento em relação ao conteúdo de compostos fenólicos. As uvas e os vinhos da variedade tinta Merlot apresentaram diferenças de acordo com a localização do vinhedos, sendo que as características das uvas foram mais importantes para o vinho resultante do que as técnicas de vinificação empregadas. Foram encontradas diferenças importantes no conteúdo e no comportamento dos compostos fenólicos entre as duas regiões representadas nesse estudo, tanto em relação a uva quanto ao vinho. As uvas cultivadas nos vinhedos do município de Dom Pedrito atingem uma maturação celular adequada, no entanto, o teor de antocianinas é menor e o teor de taninos nas sementes é superior a 50%, comportamento oposto as uvas cultivadas no município de Bento Gonçalves. A análise do potencial fenólico das uvas permite estimar o conteúdo de polifenóis totais, a porcentagem da cor devido a antocianinas poliméricas e a quantidade de procianidinas presentes no vinho a ser elaborado com uvas dessa variedade. Em relação a técnica de vinificação para a região de Dom Pedrito, recomenda-se o uso de maceração extendida (15 dias no minímo), porém há uma tendência de elevação do valor de pH do vinho resultante; o esmagamento total ou não da uva não irá influenciar esse aspecto. Durante o envelhecimento, os vinhos apresentaram resultados de acordo com a região de origem da uva, sendo que os vinhos de Dom Pedrito apresentam uma maior velocidade de polimerização; as diferenças entre os tempos de maceração diminuem com o envelhecimento do vinho para todos os vinhos analisados nesse estudo. As principais diferenças entre os vinhos dos dois municípios estudados deve-se a intensidade de cor, ao conteúdo de antocianinas, a porcentagem de cor devido a antocianinas poliméricas e ao teor de polifenóis totais nos vinhos. Estes fatos permitem afirmar, em parte, que os vinhos Merlot da Serra Gaúcha podem ser envelhecidos por mais tempo e que os vinhos Merlot oriundos da Campanha Gaúcha podem e devem ser consumidos mais jovens.
2

MATURAÇÃO FENÓLICA DE UVAS TINTAS CULTIVADAS NO RIO GRANDE DO SUL / PHENOLIC RIPENESS OF RED GRAPES GROWN IN RIO GRANDE DO SUL

Sartori, Giliani Veloso 01 December 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the recent years, the concern about wines with better sensory characteristics and biological properties has motivated many studies on the phenolic compounds. The knowledge of ripening process of these substances is related to the necessity to produce high quality wines. In this study, red grape varieties VitisviniferaMalbec, Shiraz and Tannat were evaluated in relation to their phenolic ripeness. In the first two varieties, three harvest dates of a same vineyard were evaluated. In Tannat variety, one harvest date for three different vineyards was compared. All vineyards are situated in Rio Grande do Sul, Brazil, and they were studied in the crops of 2009/2010 and 2010/2011. The grape berries were evaluated in relation to the rate of skins, seeds, and pulps; and in relation to the industrial (pH, Brix and total acidity) and phenolic ripeness. For this last evaluation, 125 berries were crushed and macerated at pH 1.0 and pH 3.2 for 4 hours. Then, the following parameters were evaluated: extractability of anthocyanins (EA%), tannins in the skins (dpell%), tannins in the seeds (Mp%), total polyphenolic index (TPI 280), total anthocyanins (ApH1,0) and extractable anthocyanins (ApH3,2). Malbec and Shiraz varieties were micro-vinified by traditional method of red vinification, then the final wine was evaluated for its physic-chemical properties (pH and total acidity) and the content of phenolic compounds (IPT, total polyphenols, tannins, and anthocyanins). The analyses were performed in triplicate and statistically evaluated by the Tukey test at 5% of probability, by Principal Component Analysis (PCA) and by linear correlation. For Malbec variety, the outcomes showed a bigger industrial and phenolic ripeness (more Brix, less Total Acidity, more IPT, more content of anthocyanins and low values of Mp% and dpell%) to the 2010/2011 crop and later harvests. The Shiraz variety showed higher levels of total anthocyanins, extractable anthocyanins, and IPT in the second harvest date. The phenolic ripeness in the second crop was also higher for this variety, which had a higher extractability of anthocyanins (less EA%) and a great ripeness of tannins from the seeds and skins (lower Mp% and higher dpell%, respectively). For Tannat variety, the sample of Itaqui (warmer region) showed a higher content of anthocyanins and IPT in the first crop, which is similar to the sample of Dom Pedrito (less warmer region than Itaqui) in the following crop. In PCA, the samples were amounted by the influence of crop and the harvest date. The wine of both varieties presented higher levels of total phenolic, anthocyanins, and IPT in the vinification of later harvest and the crop of 2010/2011. The total polyphenol content, IPT 280, and the content of anthocyanins in wines were highly correlated with the rate of the industrial ripeness of the grape, content of extractable anthocyanins (ApH 3.2), tannin content in skins (Mp%). It is possible to conclude that later harvest can provide a grape with a higher phenolic ripeness. However, this ripeness is closely related and dependent on appropriate weather conditions of harvest. / Nos últimos anos, a preocupação por vinhos com melhores características sensoriais e propriedades biológicas tem motivado inúmeros estudos sobre os compostos fenólicos. O conhecimento sobre o processo de maturação dessas substâncias vem ao encontro da necessidade de se produzir um vinho de maior qualidade. Neste estudo, as variedades tintas Vitis vinifera Malbec, Shiraz e Tannat foram avaliadas quanto à sua maturação fenólica. Para as duas primeiras variedades, avaliaram-se três datas de colheita de um mesmo vinhedo. Para a variedade Tannat, comparou-se uma data de colheita de três vinhedos distintos. Todos os vinhedos localizam-se no Estado do Rio Grande do Sul e foram estudados nas safras de 2009-2010 e 2010-2011. As bagas de uva foram avaliadas quanto à proporção de cascas, sementes e polpa, quanto à maturação industrial (pH, Brix e Acidez Total) e quanto à maturação fenólica. Para esta última avaliação, 125 bagas foram triturados e macerados em pH 1,0 e pH 3,2 por 4 horas; após, avaliou-se os seguintes parâmetros: extratibilidade de antocianinas (EA%), taninos nas cascas (dpell%), taninos nas sementes (Mp%), Índice Polifenólico Total (IPT 280), antocianinas totais (ApH1,0) e antocianinas extraíveis (ApH3,2). As variedades Malbec e Shiraz foram microvinificadas pelo método tradicional de vinificação em tinto, e o vinho final foi avaliado quanto às propriedades físico-químicas (pH e Acidez Total) e ao teor de compostos fenólicos (IPT280, Polifenóis Totais, Taninos e Antocianinas). As análises foram realizadas em triplicata e estatisticamente avaliadas pelo teste de Tukey a 5% de probabilidade, por Análise de Componente Principal (PCA) e por correlação linear. Para a variedade Malbec, os resultados evidenciaram maior maturação industrial e fenólica (maior Brix, menor Acidez Total, maior IPT280, maior teor de antocianinas e dpell%e baixos valores de Mp%) para a safra de 2010-2011 e para as colheitas mais tardias. A variedade Shiraz demonstrou maiores teores de antocianinas totais, antocianinas extraíveis e IPT na segunda data de colheita. A maturação fenólica na segunda safra também foi superior para esta variedade, observando-se maior extratibilidade de antocianinas (menor EA%) e maior maturação dos taninos das sementes e das cascas (menor Mp% e maior dpell%, respectivamente). Para a variedade Tannat, a amostra de Itaqui (região de clima mais quente) apresentou maior teor de antocianinas e IPT280 na primeira safra, equiparando-se à amostra de Dom Pedrito (região de clima menos quente que Itaqui) na safra seguinte. Na PCA, as amostras foram agrupadas pela influência da safra e data de colheita. Os vinhos de ambas as variedades apresentaram maiores teores de compostos fenólicos totais, antocianinas e IPT280 nas vinificações de colheitas mais tardias e na safra de 2010-2011. O conteúdo de polifenóis totais, IPT 280 e o conteúdo de antocianinas nos vinhos foram altamente correlacionados com os índices de maturação industrial da uva, teor de antocianinas extraíveis (ApH 3,2), teor de taninos nas cascas (dpell%) e teor de taninos nas sementes (Mp%). Conclui-se que colheitas mais tardias podem proporcionar uma uva de maior maturação fenólica. Porém, esta maturação está intimamente relacionada e dependente de adequadas condições climáticas da safra.
3

The influence of different winemaking techniques on the extraction of grape tannins

Nel, Anton Pieter 03 1900 (has links)
Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: Grape and wine phenols consist of flavanols which is the building blocks for tannins. These building blocks are called monomers which consist of catechins, epicatechins, epigallocatechins and epicatechin-gallate. Tannin is important in wine as it contributes to bitterness, mouth feel (astringency) and maturation potential of the wine. Futhermore it has a health benefit as an antioxidant. Anthocyanins are responsible for the colour of red wine. The anthocyanins combine with tannins to form stable polymeric pigments. Due to the importance of tannins and anthocyanins in wine, it is imperitative that different winemaking techniques are used to extract as much of these components as possible and that the analysis is done quickly and accurately. The aim of this study was to evaluate different winemaking techniques and their extraction of tannins and anthocyanins into the wine. Too much tannin extraction can have a negative effect on the sensory quality of the wine. Therefore a second aim was to evaluate the mouth feel properties of a Shiraz wine. A third aim was to compare the two tannin precipitation methods in terms of time efficiency, repeatability and the ease of practice. To investigate the amount of tannin concentration extracted by different winemaking techniques, two cultivars (Cabernet Sauvignon and Shiraz) were used. These treatments included the addition of an enzyme during fermentation [E], cold maceration [CM], post maceration [PM] and the combination of cold and post maceration [CM+PM]. The grapes were harvested in two different climatic areas during the 2008 and 2009 vintages. The two climatic areas were classified according to the Winkler scale as a III (Morgenster) and a IV (Plaisir de Merle). The grapes were harvested at two different ripeness levels in order to evaluate the effect of the different winemaking processes on the extraction of tannins and anthocyanins. One harvest was before (LB) and the other after (HB) the commercial harvest. The results of this study showed significant differences in the phenolic composition of the wines. It was found that the warmer area showed higher tannin concentrations than the cooler area for both cultivars. In the 2008 Cabernet Sauvignon the CM extracted higher concentrations of tannin from the cooler area at both ripeness levels. In the warmer area, CM extracted the highest tannin concentration HB, but the CM+PM extracted the highest tannin concentration from Cabernet Sauvignon at the LB and CM at the HB of the warmer area. In 2009 the PM extracted the highest concentration of tannin at the lower ripeness level, while the E treatment extracted the highest concentration from the warmer area. In the cooler area the CM+PM extracted the highest concentration of tannin at a lower ripeness level, while there were no siginicant differences between the different treatments at the higher ripeness level. The highest anthocyanin concentration was found in the cooler area. The CM treatment was found to have no effect on anthocyanin extraction. Different methods are available to quantify the tannin concentration in wine. Two of the most popular tannin analytical methods are the bovine serum albumin (BSA) and the methyl cellulose precipitable tannin (MCP) methods. The BSA method is a very complex method which uses at least 3 times more reagents than the MCP method. The MCP method only analyzes tannins, while the BSA method analyzes tannins, monomeric pigments (MP), small polymeric pigments (SPP) and large polymeric pigments (LPP). In this study a good correlation was found between the two tannin precipitation methods (R2 – 0.88). There is controversy regarding the variability of these methods. Some scientists found that the two methods show a good correlation with HPLC, while others found that there was no such correlation between the precipitation methods and the HPLC. The MCP method had a practical advantage as it could be performed in half the time required for the BSA method. This has a significant impact in scenarios where a high sample throughput is required although it only measures total tannin. The phenolic composition and mouth feel of the wine was strongly influenced by the climatic area. In the warmer area the effect of tannin concentration on mouth feel was much less than in the cooler area. The wine made of riper grapes, was more grippy, bitter and numbing than the wines made from greener grapes. The E treatment was especially associated with a dry, grippy sensation. / AFRIKAANSE OPSOMMING: Druif en wyn fenole bestaan uit flavanole wat weer die boublokke is van tanniene. Hierdie boublokke, wat bekend staan as monomere, betsaan uit katesjiene, epikatesjiene, epigallokatesjiene an epikatesjien-gallaat. Tanniene is belangrik in wyn aangesien dit bydra tot bitterheid, mondgevoel (vrankheid) asook die verouderingspotensiaal van wyn. As antioksidante hou dit ook gesondheidsvoordele in. Antosianiene dra by tot die kleur van rooiwyn. Antosianiene kombineer met tanniene om meer stabiele polimeriese pigmente te vorm. As gevolg van die belangrikheid van tanniene en antosianiene is dit van uiterse belang dat verskillende wynmaak tegnieke gebruik word om ekstraksie in die wyn te bevoordeel en dat die analitiese metode so vinnig en akkuraat as moontlik gedoen word. Die eerste doel van hierdie studie was om die ekstraksie van tanniene en antosianiene deur middel van verskillende wynmaak tegnieke te evalueer. Te veel tanniene in die wyn kan negatiewe sensoriese kwaliteit tot gevolg het. Daarom is die tweede doel om die sensoriese kwaliteit van Shiraz wyn te evalueer. Die derde doel van hierdie studie was die twee tannien presipitasie metodes met mekaar te vergelyk in terme van die moeilikheidsgraad van die metode, tyd doeltreffendheid en herhaalbaarheid. Verskillende wynmaak tegnieke (ensiem byvoegings [E], koue maserasie [CM], verlengde dopkontak [PM] en ‘n kombinasie van koue maserasie en verlengde dopkontak [CM+PM]) is vergelyk ten opsigte van tannien en antiosianien ekstraksie. In 2008 en 2009 is twee kultivars (Cabernet Sauvignon en Shiraz) in twee verskillende klimatologiese areas gepars. Hierdie areas is geklassifiseer in die Winklerskaal as ‘n IV (Plaisir de Merle) en ‘n III (Morgenster). Om die effek van die verskillende wynmaak tegnieke op die ekstraksie van antosianiene en tanniene te vergelyk, is hierdie twee kultivars by twee verskillende rypheidsgrade geoes. Die eerste oes was net voor kommersiële oes (LB) en die tweede oes het net na kommersiële oes (HB) plaasgevind. Die 2009 Shiraz wyn is organolepties beoordeel om die effek van die verskillende wynmaak tegnieke op die wyn se mondgevoel te vergelyk. Die resultate van hierdie studie toon beduidende verskille in die fenoliese samestelling van die wyne. Dit is gevind dat die warmer area hoër tannien konsentrasies het as die koeler area. In 2008 het die CM+PM die meeste tanniene uit die Cabernet Sauvignon geëkstraheer by LB en die CM by HB in die warmer area. Die CM het in die koeler area meer tanniene geëkstraheer by beide die LB en HB rypheidsgrade. In 2009 het PM die meeste tanniene geëkstraheer by LB terwyl E die meeste tanniene geëkstraheer in die warmer area. In die koeler area het CM+PM die meeste tanniene geëkstraheer, terwyl geen van die behandelings ‘n effek gehad het by HB. Die meeste antosianien konsentrasie was in die koeler area gevind as in die warmer area. In beide 2008 (LB en HB) en 2009 (LB) het CM die meeste antosianiene geëkstraheer, terwyl geen behandeling ‘n effek gehad het by HB. Twee van die mees populêre tannien analitiese metodes is die BSA (bovine serum albumien) en die MCP (metielsellulose presipitasie) metodes. Die BSA metode is ‘n baie meer ingewikkelde metode waarvoor drie keer meer reagense gebruik word as vir die MCP metode. Maar waar die MCP net tanniene ontleed, ontleed die BSA metode tanniene, monomere (MP), klein polimeriese pigmente (SPP) en groot polimeriese pigmente (LPP). Dit help indien daar gekyk wil word na die evolusie van polimeriese pigmente. In hierdie studie is bevind dat daar ‘n redelike korrelasie (R2 – 0.88) tussen die BSA en MCP metode bestaan. Die herhaalbaarheid van die metodes het redelike kontroversie veroorsaak, waar sommige navorsers bevind het dat die BSA metode nie so herhaalbaar is soos eers bevind is nie. Die MCP metode het ’n praktiese voordeel aangesien dit in die helfde van die tyd van die BSA metode uitgevoer kan word. Dit het ‘n groot impak indien ‘n groot hoeveelheid monsters ontleed moet word. Die fenoliese samestelling en mondgevoel word sterk beïnvloed deur die klimatologiese area. In die warmer area was die effek van tannien konsentrasie op mondgevoel kleiner as in die koeler area. Die wyn van ryper druiwe het meer harder, verdowingseffek en bitter nasmaak gehad as by die wyn van groener druiwe. Die ensiem behandeling was meer geassossieerd met droë mond gevoel.
4

CARACTERIZAÇÃO FÍSICO-QUÍMICA, FENÓLICA E SENSORIAL DA CV. MARSELAN DE DIFERENTES REGIÕES DO RIO GRANDE DO SUL / CHARACTERIZATION PHYSICO-CHEMICAL, PHENOLIC AND SENSORY OF CV. MARSELAN OF DIFFERENT REGIONS OF THE RIO GRANDE DO SUL

Arenhart, Márcia 20 March 2015 (has links)
There is a great diversity of vines in the world, generating high variability characteristics of the wines produced. With the increased interest motivated by health benefits, making room for the growth of consumption and the grape and wine market potential, the search for varieties able to adapt to different climatic conditions and the growing consumer demand for wine quality, introduces the 'Marselan' piecemeal viticulture scenario. 'Marselan' is a red grape vinifera, obtained by crossing the 'Grenache' and 'Cabernet Sauvignon'. The Rio Grande do Sul has the largest percentage of cultivated area with grape in Brazil, and is the largest producer of wine. The quality of products derived from the grape is dependent on its physicochemical properties and phenolic composition characteristics of cultivars. This study aims to characterize physicochemical the cultivate and the varietal wine, and also describe the sensory profile of the varietal wine Marselan obtained from grapes produced in the regions of the Campanha Gaúcha, Serra Gaúcha and Serra do Sudeste of Rio Grande do Sul. Six samples of grapes produced different regions were collected. Part of berries was frozen in liquid nitrogen and stored in a freezer for further analysis and preparation of extracts, the remainder was used for the microvinification. Analysis of total polyphenols, total flavonoids, procyanidins, tannins, anthocyanins, polymeric pigments, intensity and color tone, color characteristics by the CIE L* a* b* space, acidity, pH, total soluble solids, total sugars (reducing and non-reducing) and antioxidant capacity were performed. The sensory characteristics of the wines were determined by quantitative descriptive analysis with a team of 10 trained panelists. The grape and wine samples Marselan differ in physicochemical parameters evaluated and sensory analysis. Industrial maturation, phenolic ripeness, phenolic compounds and antioxidant capacity data of 'Marselan' demonstrated their adaptability to all regions of Rio Grande do Sul, but are highly dependent on the weather, which provide different features. All red wines are in accordance with the standards established by Brazilian law. The total polyphenol content (2047.07 to 4777.98 mg L-1) and anthocyanins (645.20 874,67mg the L-1) found in a young wine, Marselan presents a good potential for development of guard wines. The antioxidant capacity follows the trend of phenolic compounds. Regarding the color parameters of the wine samples are somewhat different, but it is not possible to characterize differences in the area and its color is characteristic of young wines. The method of quantitative descriptive analysis revealed that the studied samples have distinct sensory profiles, except in the aroma, which indicates the typical characteristics of the cultivar studied for the aromas of red fruits, dried fruits, woody and sweet. The attributes violet color, translucent, fruity flavor, astringency and persistence are the most important to discriminate samples of red wine, however the other attributes as herbaceous aromas, alcohol and floral, bitter flavors, acid and woody, pungency and body help to describe sensorily the cv. Marselan. It is possible to discriminate sensory samples of red wine based on the production region. / Existe uma diversidade muito grande de videiras no mundo, gerando elevada variabilidade de características dos vinhos produzidos. Com o aumento de interesse motivado pelos benefícios à saúde, abrindo espaço para o crescimento do consumo e do potencial do mercado da uva e do vinho, a busca de variedades capazes de se adaptar as condições climáticas diferenciadas e a procura crescente do consumidor por vinhos de qualidade, introduz a Marselan aos poucos ao cenário da viticultura. Marselan é uma uva tinta vinífera, obtida pelo cruzamento da Grenache e Cabernet Sauvignon . O Rio Grande do Sul detém a maior percentagem de área cultivada com uva no Brasil, além de ser o maior produtor de vinho. A qualidade dos produtos derivados da uva é dependente das suas propriedades físico-químicas e da composição fenólica características das cultivares. O presente trabalho tem como objetivo caracterizar físico-quimicamente a cultivar e o vinho varietal, e também descrever o perfil sensorial do vinho varietal Marselan obtido de uvas produzidas nas regiões da Campanha Gaúcha, Serra Gaúcha e Serra do Sudeste, do Rio Grande do Sul. Seis amostras de uvas produzidas diferentes regiões foram coletadas. Parte das bagas foi congelada em nitrogênio líquido e armazenada em freezer para posterior elaboração de extratos e análise, o restante foi destinado à microvinificação. Foram realizadas análises de polifenóis totais, flavonóides totais, procianidinas, taninos, antocianinas, pigmentos poliméricos, intensidade e tonalidade de cor, características cromáticas pelo espaço CIE L*a*b*, acidez, pH, sólidos solúveis totais, açúcares totais (redutores e não redutores) e capacidade antioxidante. As características sensoriais dos vinhos foram determinadas por Análise Descritiva Quantitativa com uma equipe de 10 provadores treinados. As amostras de uva e vinho Marselan apresentam diferenças nos parâmetros físico-químicos avaliados e na análise sensorial. Os dados de maturação industrial, maturação fenólica, compostos fenólicos e capacidade antioxidante da Marselan demonstraram a sua adaptação a todas as regiões do Rio Grande do Sul, porém é altamente dependente das condições climáticas, as quais conferem características bem diferenciadas. Todas as amostras de vinho tinto encontram-se de acordo com os padrões estabelecidos na legislação brasileira. Pelo teor de polifenóis totais (2047,07 a 4777,98 mg L-1) e antocianinas (645,20 a 874,67mg L-1) encontrados no vinho ainda jovem, a Marselan apresenta um ótimo potencial para elaboração de vinhos de guarda. A capacidade antioxidante acompanha a tendência dos compostos fenólicos. Em relação aos parâmetros de cor dos vinhos as amostras apresentam diferenças entre si, mas não é possível caracterizar diferenças quanto à região e sua cor é característica de vinhos jovens. O método da Análise Descritiva Quantitativa revelou que as amostras estudadas apresentam perfis sensoriais distintos, exceto no aroma, o que indica a tipicidade da cultivar estudada para os aromas de frutas vermelhas, frutas secas, madeirizado e doce. Os atributos cor violeta, translúcido, sabor frutado, adstringência e persistência são os mais importantes para discriminar as amostras de vinho tinto, no entanto os outros atributos como aromas herbáceo, alcoólico e floral, sabores amargo, ácido e madeirizado, pungência e corpo auxiliam a descrever sensorialmente a cv. Marselan. É possível discriminar sensorialmente as amostras de vinho tinto com base na região de produção.

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