Thesis (MscAgric (Viticulture and Oenology))--University of Stellenbosch, 2009. / South Africa is the eighth largest wine producing country in the world and face stiff competition on the world market. Cabernet Sauvignon is the most planted red cultivar in the world as well as in South Africa and can be seen as the wine by which countries are judged. The aim of this study was to investigate suitable, practical maturity parameters or combinations thereof to determine the optimal time to harvest Cabernet Sauvignon grapes under South African conditions. The following parameters were investigated during this study: seed lignification, maturity indexes, anthocyanin concentration per berry, sensory criteria (grape skins tasting and wine) and phenolic content. Berry development in four Cabernet Sauvignon vineyards in different South African winegrowing areas were investigated over the 2003, 2004 and 2005 seasons. The first parameter to be investigated was seed lignification percentages. Seasonal differences at commercial harvest were observed with values of 2004 varying between 73% and 91% compared to 59% and 80% for the 2003 and 2005 seasons but commercial harvest was two weeks later during the 2004 season. During this study it was found that seeds never reached 100% lignification for Cabernet Sauvignon as was found in previous work to indicate grape maturity. The development of anthocyanins also peaked well before the maximum seed lignification was reached. It therefore appears that seed lignification is not suitable for the determination of grape maturity for Cabernet Sauvignon grapes under South African conditions. The second parameter to be investigated was maturity indexes (Balling / Titratable Acidity (TA), Balling × pH, Balling × pH2). The best wine values were used to determine the optimal maturity index values. Morgenster was the only vineyard to consistently give values that corresponded to previously reported data (index values). Anhöhe and Plaisir de Merle reported higher maturity values than that reported in literature and seasonal variation was observed. Maturity index values for the best wines varied between 88 and 101 (Balling × pH) for Anhöhe during 2003 and 2005 seasons, but increased too between 97 and 107 (Balling × pH) for 2004. The maturity index values were found to be vineyard and season dependant, with warmer areas reaching higher values. From this study it appears that maturity index values as a singular maturity parameter does not give a good indication of berry maturity in all seasons or vineyards. Thirdly, the berry anthocyanin concentration (mg / berry and mg / g berry) were investigated and comparable trends were found between the four vineyards. However vineyards in warmer, drier regions (Anhöhe) tended to have higher anthocyanin concentrations per gram berry. The more vigorous vineyard of Morgenster consistently exhibited a higher anthocyanin concentration per berry. This can be explained by the ratio of skin to pulp between small berries (Anhöhe, 0.95 g - 2004) and larger berries South Africa is the eighth largest wine producing country in the world and face stiff competition on the world market. Cabernet Sauvignon is the most planted red cultivar in the world as well as in South Africa and can be seen as the wine by which countries are judged. The aim of this study was to investigate suitable, practical maturity parameters or combinations thereof to determine the optimal time to harvest Cabernet Sauvignon grapes under South African conditions. The following parameters were investigated during this study: seed lignification, maturity indexes, anthocyanin concentration per berry, sensory criteria (grape skins tasting and wine) and phenolic content. Berry development in four Cabernet Sauvignon vineyards in different South African winegrowing areas were investigated over the 2003, 2004 and 2005 seasons. The first parameter to be investigated was seed lignification percentages. Seasonal differences at commercial harvest were observed with values of 2004 varying between 73% and 91% compared to 59% and 80% for the 2003 and 2005 seasons but commercial harvest was two weeks later during the 2004 season. During this study it was found that seeds never reached 100% lignification for Cabernet Sauvignon as was found in previous work to indicate grape maturity. The development of anthocyanins also peaked well before the maximum seed lignification was reached. It therefore appears that seed lignification is not suitable for the determination of grape maturity for Cabernet Sauvignon grapes under South African conditions. The second parameter to be investigated was maturity indexes (Balling / Titratable Acidity (TA), Balling × pH, Balling × pH2). The best wine values were used to determine the optimal maturity index values. Morgenster was the only vineyard to consistently give values that corresponded to previously reported data (index values). Anhöhe and Plaisir de Merle reported higher maturity values than that reported in literature and seasonal variation was observed. Maturity index values for the best wines varied between 88 and 101 (Balling × pH) for Anhöhe during 2003 and 2005 seasons, but increased too between 97 and 107 (Balling × pH) for 2004. The maturity index values were found to be vineyard and season dependant, with warmer areas reaching higher values. From this study it appears that maturity index values as a singular maturity parameter does not give a good indication of berry maturity in all seasons or vineyards. Thirdly, the berry anthocyanin concentration (mg / berry and mg / g berry) were investigated and comparable trends were found between the four vineyards. However vineyards in warmer, drier regions (Anhöhe) tended to have higher anthocyanin concentrations per gram berry. The more vigorous vineyard of Morgenster consistently exhibited a higher anthocyanin concentration per berry. This can be explained by the ratio of skin to pulp between small berries (Anhöhe, 0.95 g - 2004) and larger berries (Morgenster, 1.82 g – 2004). Wine colour density (A420+A520) followed the same trend as the anthocyanin concentrations of the homogenate. Grape skins (G) were used to make an artificial wine that was evaluated by an expert panel to determine the development of the grapes. Wines (W) made from sampled batches were also evaluated by an expert panel for: colour intensity, vegetative, red berry, black berry with spice, acidity, astringency and general quality. Vegetative aromas and acidity decreased and red and black berry with spice increased during ripening for both berries and wine. Colour intensity also increased, corresponding to an increase in perceived general quality score. Correlations between general quality of both the grape skins tasting and wines were investigated. Balling showed a strong correlation with general quality of the grape skins tasting (r = 0.76; p = 0.00) but not as strongly with subsequent wines (r = 0.57; p = 0.00). Anthocyanin concentration (mg / g berry) of the berries (r = 0.36; p = 0.00), perceived colour intensity of grapes (r = 0.69; p = 0.00) and wine (r = 0.84; p = 0.00) correlated with general wine quality. The tasting panel identified wines that were statically better than the rest for each season and vineyard. Maximum berry anthocyanin concentration coincided with wines rated as the best by the tasting panel. More than one wine was identified during the maximum anthocyanin peak that did not differ statistically from the best wine. It appears from this study that a window period exists at the maximum anthocyanin peak, where wines of comparable quality, but different style, can be produced. Principal component analysis (PCA) was used to determine the least number of suitable parameters that could distinguish between unripe and ripe grapes in order to establish a grape maturity model. These differences were successfully described by Balling, TA, pH, potassium (K+), tartaric and malic acid. Anthocyanin concentration could further distinguish between ripe and overripe grapes in the model. From these parameters the minimum and maximum values were used to construct a universal ripeness model containing data from all four vineyards. Variation between the four vineyards caused too much overlapping in the universal model data as the vineyards were situated in different climatic regions according to the Winkler temperature model. On a per vineyard basis this did not occur to the same extend. The best rated Cabernet Sauvignon wines correlated strongly with soluble solid content; colour and quality perceptions of grapes, but large seasonal differences resulted in larger grape compositional variances than that of the individual vineyards in the different climatic zones. This illustrated the difficulty of pinpointing a specific parameter to indicate optimal ripeness. From this study it is clear that a universal maturity model for Cabernet Sauvignon berries is not attainable at present, but individual vineyard models shows the most potential. A preliminary study into the differences of the phenolic composition was done using reverse phase high performance liquid chromatography (RP-HPLC) on the homogenate and wine. Malvidin-3-glucoside and total anthocyanins followed comparable trends to that found for the Iland method. Strong correlations (r > 0.9) were found between the malvidin- 3-glucoside and malvidin-3-glucoside-acetate and p-coumarate; this was also true for the total anthocyanins in both homogenate and wine. Wines identified by a tasting panel to be the best quality, corresponded with the maximum anthocyanin concentration (mg / L) peak in the homogenate. Dense canopies at the Morgenster vineyard over the three seasons lead to lower total anthocyanin and quercetin-3-glucuronide concentrations compared to the Anhöhe and Plaisir de Merle vineyards. The shading of bunches by the dense canopy most likely contributed to this. Catechin, epicatechin, proanthocyanidin and polymeric phenol concentrations decreased significantly from veraison until harvest. Seasonal differences were noted in the four vineyards. No correlations could be found between the general wine quality and the phenolic compounds, but a weak trend was observed for total anthocyanins in the homogenate. A trend was found with the total flavan-3-ol to anthocyanin ratio determined by RP-HPLC analysis of the grape homogenates (r = 0.40, p = 0.00). This ratio varied between 1 and 3 for the wines rated as being the best quality. Phenols by themselves do not give a clear indication of optimal harvest time. From this study it appears that no single parameter could consistently indicate optimal ripeness over the seasons or per vineyard, but the maximum berry colour (anthocyanin concentration) did give an indication of optimal harvesting time. It is clear that a combination of parameters could predict the optimal time more precisely as with the above mentioned model but more research is needed to this end.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The rate of nitrogen (N) in grapevines in the Rio Grande do Sul (RS) State, Southern Brazil, is established considering N content in leaves or leaves petioles and yield expectation limits. Once N fertilization needs have been diagnosed, the N is applied in indefinite times. However, N fertilization recommendations don t consider the impact of N fertilization in the yield, the consequences on grape composition and the contribution of N of crop residues to mineral nutrition of grapevines. The objective of this work was to estimate the recovery and accumulation of N in grapevines and the effect in the yield and grape composition. Three studies were carried on. Study 1, recovery, distribution and accumulation of N fertilizer was studied, in Cabernet Sauvignon grapevines, located at Bento Gonçalves city, area of the Serra Gaúcha (experiment 1), and Santana do Livramento city, area of the Campanha (experiment 2), in RS, Southern Brazil. In the experiment 1 and 2 the plants were fertilized with 15N in four forms and, when grapes were mature, plants were fractionated, oven-dried, weighted and analysed for total N and 15N enrichment. Study 2, grape yield and composition of grapevines treated with different amounts of N were studied, in the vineyards of the Study 1. Grapes were collected when ripe and yield was evaluated. Must soluble solids, pH, total acidity, tartaric acid, malic acid, total phenols, anthocyanins and N ammonia were evaluated in part of the berries. The remaining berries were triturated and total N, P, K, Ca and Mg were evaluated. Study 3, decomposition and nutrient release by aerial organs of Lolium perenne (LP) and Trifolium repens (TR) (experiment 1), and grapevines uptake of the N derived from decomposing material (experiment 2) were studied in Chardonnay grapevines located at the experimental Station of the University of Bologna, Italy. In experiment 1, 2 g (DW) of 15N-labelled litter of LP and TR were placed into litter bags which were placed on the vineyard soil surface. Collection of bags LP and TR was performed 8 (June) and 16 (August) weeks from the deposition. Remaining biomass, 15N, N, C, P, K, Ca, Mg and S concentrations were determined. In experiment 2, 30 g plant-1 of dry litter of LP and TR were placed on the herbicided soil under the grape plants. Grapevine leaves were collected 8 and 16 weeks from litter deposition; after 16 weeks, one year (including bunches) and two years shoots were collected, oven-dried, weighted and analysed for total N and 15N enrichement. Results showed that the absorbed N is distributed and accumulated especially in leaves and that most of the N found in the plant was not derived from the fertilizers but from the organic matter already present in the soil. However, N fertilization increased grape yield in the Serra Gaúcha grapevines. The rate can be split 25% at the beginning of bud burst + 25% at bud burst + 25% at flowering + 25% at growth berries; 50% at the beginning of bud burst + 50% at bud burst and 50% at flowering + 50% at growth berries. Moreover, N fertilization altered the grape composition, especially decrease the amount of anthocyanins. LP and TR residues decomposed at the same rate, but nutrient release was different between the two species and varied according with mineral element. The amount of N that grapevines recovered from the decomposing litter was low and similar for LP and TR residues. / No Rio Grande do Sul (RS), a dose de nitrogênio (N) para a videira é definida a partir do seu teor total na folha inteira ou no pecíolo, e na expectativa de produção. Quando diagnosticada a necessidade de aplicação, recomenda-se o seu parcelamento em épocas incertas. Entretanto, essa recomendação não infere informações sobre o impacto do N aplicado na produção e na composição da uva. Também não se considera a contribuição do N dos resíduos de plantas de cobertura depositados na superfície do solo. O presente trabalho teve como objetivo estudar a recuperação e acumulação de N em videiras e seu efeito na produtividade e na composição da uva e do mosto. Foram conduzidos três estudos: Estudo 1, realizado para estimar a recuperação, distribuição e a acumulação de N aplicado ao solo pela videira. Esse foi composto por dois experimentos: Experimento 1, implantado em um vinhedo de Cabernet Sauvignon na Embrapa Uva e Vinho, Bento Gonçalves (RS), e o experimento 2, instalado na Empresa Pernod Ricard Brasil/Almadén, Santana do Livramento (RS). Nos experimentos 1 e 2 as videiras foram submetidas à aplicação de uma dose de N com 3% de átomos de 15N, em quatro modos de parcelamento. Na maturação da uva, as plantas foram colhidas, fracionadas, secas, determinada a matéria seca (MS) e analisado os totais de N e 15N. O Estudo 2 foi realizado para avaliar a produtividade e a composição da uva e do mosto, em videiras submetidas à aplicação de N. O Estudo 2 foi formado por dois experimentos: Experimento 1, implantado no vinhedo do experimento 1 do Estudo 1, as videiras receberam cinco doses de N e o experimento 2, instalado no vinhedo do experimento 2 do Estudo 1, as videiras foram submetidas à aplicação de seis doses de N. Nos experimentos 1 e 2 a uva foi colhida, determinada a produção e no seu suco avaliado os sólidos solúveis totais, o pH, a acidez total, o ácido tartárico e málico, os polifenóis totais, as antocianinas e o N amoniacal. Além disso, na baga foram analisados os totais de N, P, K, Ca e Mg. O Estudo 3 foi realizado para determinar a contribuição de N derivado da decomposição de resíduos de azevém (Lolium perenne) e trevo branco (Trifolium repens) para a videira. Esse compreendeu dois experimentos instalados em vinhedo de Chardonnay, em Bologna, Itália. No experimento 1, os resíduos de azevém perene e de trevo branco foram colocados no interior de bolsas teladas e depositados no solo. Ao longo do ciclo das videiras as bolsas teladas foram coletadas, determinada a MS remanescente e analisado os totais de 15N, N, C, P, K, Ca, Mg e S. No experimento 2, os resíduos das espécies foram colocados na superfície do solo e na maturação da uva as videiras foram colhidas, fracionadas, secas, determinado a MS e analisado os totais N e 15N. Os resultados obtidos mostram que o N adicionado e absorvido no ano é distribuído e acumulado, preferencialmente, nas folhas, mas a maior parte do N presente na videira é derivada de outras formas, que não a do fertilizante. Entretanto, existe aumento na produção quando da aplicação de N na Serra Gaúcha, podendo a dose ser parcelada 25% no início da brotação+25% na brotação+25% na floração+25% no crescimento das bagas; 50% no início da brotação+50% na brotação e 50% na floração+50% no crescimento das bagas. A aplicação de N altera a composição da uva, especialmente, diminui a quantidade de antocianinas no mosto. Os resíduos de azevém perene e trevo branco depositados na superfície do solo são decompostos com a mesma taxa no ciclo vegetativo e produtivo da videira, porém liberam nutrientes em taxas diferentes. No entanto, isso tem pouca importância, pois as plantas recuperam porcentagens pequenas e iguais de N derivado dos resíduos das duas espécies.

La connaissance de la composition phénolique du Cabernet-Sauvignon (CS) et du Merlot (M) dans la région vitivinicole du bordelais a un intérêt majeur pour définir la structure et la qualité tannique (astringence et amertume) des raisins et des vins. La composition en tanins et anthocyanes de raisins et de vins issus du Cabernet Sauvignon et du Merlot ainsi que leur perception tannique ont été recherchées. L’étude raisins a été réalisée pour cinq parcelles de la région bordelaise (Pauillac, Margaux, Saint Emilion (1), Saint Emilion (2) Côtes de Bourg) pour trois millésimes consécutifs : 2006, 2007 et 2008 et différents types de sol : Limoneux, Sableux, Limono-Sableux 1, Limono-Sableux 2, Limon argilo-sableux pour le M et Limono-argileux, Sablo-limoneux 1, Limono-sableux, Sablo-limoneux 2 et Limoneux pour le CS. Les monomères [(+)-catéchine (C), (-)-épicatéchine (EC), (-)-épicatéchine-O-gallate] et les oligomères (dimères: B1, B2, B3, B4 et trimère Cat-Cat-Epi) des procyanidines, ont été identifiées et quantifiées pour les extraits de raisins (pépins et pellicules) et pour les vins par CHLP-UV-Fluo. Le pourcentage de galloylation (%G), le pourcentage de prodelphinidines (%P) ainsi que le degré moyen de polymérisation (DPm) des tanins oligomères des raisins et des tannins de vin ont été déterminés par CHLP-UV-SM. L’intensité d’astringence et d’amertume des tanins oligomères des raisins (pépins et pellicules) et des vins ont été estimées par analyse sensorielle. Les anthocyanes monoglucosides [cyanidine-3-O-glucoside (Cy), delphinidine-3-O-glucoside (Dp), paeonidine-3-O-glucoside (Pn), malvidine-3-O-glucoside (Mv), petunidine-3-O-glucoside (Pt)] et les anthocyanes acétylées (paeonidine-3-O-glucoside, malvidine-3-O-glucoside) et coumaroylées (paeonidine-3-O-glucoside, malvidine-3-O-glucoside) ont été identifiées et quantifiées par CLHP-UV-SM dans les extraits de pellicules et dans les vins. L’influence du sol, du millésime, et du cépage (pour les raisins et les vins) ont été explorés. Le millésime, dans les deux cas (raisins et vins), a un effet très significatif et domine celui du cépage (raisins et vins) et celui du sol (raisins) sur la plupart des variables étudiées. Selon le type de sol et le millésime, la qualité tannique des raisins est évaluée. Les pépins de CS issus du sol Limono-sableux présentent une grande variabilité au niveau du DPm (3,8 à 7,2) et au niveau du % G (19,0 à 51,3). Ceux-ci sont plus astringents et amers que les pépins issus des autres types de sols. Les pépins (CS) du millésime 2006 sont plus astringents et amers que ceux des autres millésimes, même s’ils sont caractérisés par des valeurs de DPm et % G deux fois moins élevées que ceux de 2007. Pour les sols Limono-sableux, les pellicules (CS) possèdent les valeurs moyennes de DPm (30,89) et de % G (5,07) les plus élevées et sont perçues comme les plus astringentes. Les pépins de M issus du sol Limono-sableux 1 et du sol Limoneux présentent des DPm maximums de 3,20 et 3,03 ; avec des intensités moyennes d’astringence et d’amertume les plus élevées pour le sol Limono-sableux 1. Pour les pépins de M, les intensités d’astringence sont du même ordre pour les 3 millésimes. Les pépins (M) de 2007 possèdent le % G le plus élevé (33,34) et sont perçus plus amers par rapport aux autres millésimes. Les pellicules de M des sols sableux sont plus astringentes avec une variation forte du % P (3,8 à 14,0). Pour le M, les pellicules issues du sol Limoneux sont moins astringentes et se caractérisent par un DPm moins élevé (10,42) par rapport aux autres sols. Pour les pépins, le CS présente un DPm (4,15) et un % G (26,12) plus élevés que celui du M (2,74 et 21,22 %). Pour les pellicules, le CS se caractérise par un DPm (22,85), un % G (3,24 %) et un % P (14,99 %) plus élevés que ceux de M (DPm = 19,42, % G = 1,31 %, % P= 5,54). Pour les trois millésimes étudiés, le cépage n’a influencé ni l'amertume ni l'astringence pour les pépins et les pellicules. Les différences significatives et consécutives sur la composition en anthocyanes entre CS et M pour les trois millésimes portent sur : la Cy, la Pt, la Pn, la Mv et les anthocyanes acétylées et coumaroylées. Les teneurs en anthocyanes acétylées sont deux fois plus élevées pour le CS (6,99 mg/g), alors que le M présente des teneurs en anthocyanes coumaroylées (3,31 mg/g) plus élevées que celles du CS (1,99 mg/g). L’étude de la qualité tannique sur vins, a été réalisée pour 24 millésimes issus de CS et 7 millésimes issus de M. Les teneurs en composés phénoliques, en anthocyanes, en tanins totaux, en monomères des tanins (C+EC), la teinte, l’IC’ (intensité colorante), le % G, le % P et le DPm ainsi que l’intensité de l’astringence apparaissent comme des données pertinentes pour différencier les vins en fonction du millésime. Des corrélations entre l’âge des vins et : le DPm, la teinte, l’astringence, les teneurs en composés phénoliques totaux, en monomères de tanins (C+EC) et en tanins totaux ont pu être obtenues. La caractérisation qualitative des tanins et des vins est établie par corrélation entre l’astringence et le DPm (R2 = 0,509, p = 0,051, CS ; R2 = 0,780, p = 0,000, M). De plus, le DPm apparaît être un marqueur du millésime (R2 = 0,796, p = 0,000 ; CS et R2 = 0,946, p = 0,000 ; M). Nous proposons une échelle reliant le DPm des vins en fonction du millésime et de la perception tannique (astringence). Les vins issus du M sont caractérisés par une moindre richesse en composés phénoliques totaux, en tanins, en anthocyanes, en DPm, en % G, en % P ainsi que par une intensité d’astringence moins importante par rapport a ceux de CS. Le TAV (titre alcoométrique volumique, % vol) semble être positivement corrélé à l’amertume (r = 0,39, p < 0,05). / Cabernet-Sauvignon (CS) and Merlot (M) phenolic composition is of paramount importance to grapes and red wines structure and quality (astringency and bitterness) in Bordeaux winegrowing region. Tannins and anthocyanins composition as well as tannin perception have been studied for Cabernet-Sauvignon and Merlot grapes and wines. Grapes study was carried out with samples from five vineyards located in Bordeaux (Pauillac, Margaux, Saint Emilion (1), Saint Emilion (2)and Côtes de Bourg) for three consecutive vintages (2006, 2007 and 2008) and for different soil types (Silty, Sandy, Silty-sandy 1, Silty-sandy 2, Silty clay-sandy for M and Clay-loam, Sandy-silty 1, Silty-sandy, Sandy-silty 2 and Silty for CS). The proanthocyanidin monomers [(+)-catechin (C), (-)-epicatechin (EC), (-)-epicatechin-O-gallatte] and oligomers [dimers: B1, B2, B3, B4 and trimer Cat-Cat-Epi] from grape extracts (seed and skin) and wine were identified and quantified by HPLC-UV-Fluo. Percentage of galloylation (%G), percentage of prodelphinidins (%P) as well as mean degree of polymerization (mDP) of grape tannins oligomers and wine tannins were determined by HPLC-UV-MS. Sensory analysis concerning astringency and bitterness intensity of grape tannins oligomers (skins and seeds) and wines was also performed. The anthocyanic composition of glucosides [cyanidin-3-O-glucoside (Cy), delphinidin-3-O-glucoside (Dp), paeonidin-3-O-glucoside (Pn), malvidin-3-O-glucoside (Mv), petunidin-3-O-glucoside (Pt)] acetylated glucosides (paeonidin-3-O-glucoside, malvidin-3-O-glucoside]) and coumarylic glucosides (paeonidin-3-O-glucoside, malvidin-3-O-glucoside) of skins extracts and wines were analysed by HPLS-MS. Soil, vintage and grape variety influence on the above parameters are explored. The vintage in both cases (grapes and wines), has a significant effect and dominates that of grape variety (grape and wine) and soil (grape). Depending on soil type and vintage, tannins grapes quality is evaluated. CS seeds from Silty-sandy soil present a great variability on mDP (3.8 to 7.2) and on % G (19.0 to 51.3). The above seeds are more astringent and bitter than those from other soil types. The 2006 seeds (CS) are more astringent and bitter than these from the other vintages, even if they are characterized by G % and mDP values two times lower than these of 2007. Skins (CS) of Silty-sandy soils, have the highest mDP (30.89) and % G (5.07) average values and are perceived as more astringent. M seeds from Silty-sandy 1 and Silty soil have the maximum mDP values (3.20 and 3.03); Silty-sandy 1 M seeds present the highest astringency and bitterness intensities. For M seeds, astringency intensities present the same values for the 3 vintages. The 2007 seeds (M) have the highest % G (33.34) and are perceived bitter than those from the other vintages. M skins from Sandy soils are the most astringent with a strong variation on % P (3.8 to 14.0). M skins from Silty soils are less astringent and are characterized by lower mDP values (10.42) than these from other soils. In seeds, CS presents a mDP (4.15) and a % G (26.12) higher than M (2.74 and 21.22 %). CS skins are also characterized by higher mDP (22.85), % G (3.24 %) and % P (14.99 %) values than M (mDP = 19.42, % G = 1.31 % and %, P = 5.54 %). For all three vintages studied, the grape variety does not affect the astringency and bitterness intensity in both skin and seed tannins extracts. The consistent differences between CS and M for the three vintages on anthocyanin composition are on : Cy, Pt, Pn, Mv, acetylated and coumarylic anthocyanin levels. Acetylated anthocyanins values are two times highest for CS (6.99 mg/g), while M presents (3.31 mg/g) coumarylic anthocyanin levels higher than CS (1.99 mg/g). The study concerning wine tannin quality, was conducted for 24 vintages for CS and for 7 vintages for M. Total phenolic compounds, total anthocyanins, total tannins, tannin monomers (C+EC), hue, IC' (color intensity), % G, % P, mDP and astringency intensity differentiate wines according to vintage. The correlation between wine age and: mDP, hue, astringency, total phenolic compounds, tannin monomers (C+EC) and total tannin levels are obtained. The qualitative tannin and wine characterization is established by correlation between astringency and mDP (R 2 = 0.509, p = 0.051, CS; R2= 0.780, p = 0.000, M). In addition, the mDP appears to be vintage marker (R 2 = 0.796, p = 0.000; CS and R2 = 0.946, p = 0.000; M). Scale patterns between wine mDP and both ageing and tannin perception (astringency) are proposed. M wines are characterized by lower levels of total phenolic compounds, tannins, anthocyanins, mDP, % G, % P % levels as well as by lower astringency intensity than CS wines. Ethanol level seems to be positively correlated to bitterness (r = 0.39, p < 0.05).

The research project, Optimization of an array of Peptidic Indicator Displacement Assays for the Discrimination of Cabernet Sauvignon Wines, describes the multiple step lab trials conducted to optimize an array of ensembles composed of synthesized peptides and PCV:Cu+2 complexes for the differentiation of seven Cabernet Sauvignon wines with different tannin levels. This report also includes the methods and analysis used. The analysis interpreted by principal component analysis. / text

Thesis (MScAgric)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: In an attempt to reduce the pH of juice and wine, different fertiliser applications and canopy management practices were evaluated in a field trial. Fertiliser treatments consisted of no, CaS04, Ca(OH)2, and MgS04 fertilisation. Canopy management was as follows: suckering (leaving only two shoots per bearer), tipping, vertical shoot positioning and removal of lateral shoots and yellow leaves in the bunch zone (Canopy 1); suckering (leaving three shoots per bearer), vertical shoot positioning as well as topping (Canopy 2); vertical shoot positioning and topping (Canopy 3). The field trial was conducted in the Paardeberg region on the farms Meerlus and Kersfontein. The vineyard at Meerlus was Cabernet franc/R99 with a high canopy density and a good root distribution, established on a sandy loam soil of granite origin, with a low subsoil pH and a high K content. The vineyard at Kersfontein was Cabemet Sauvignon/101-14 Mgt with a lower canopy density and a less extensive root distribution, also established on a sandy loam soil of granite origin, but with a low top- and subsoil pH and a higher K content. Fertilisation had no significant influence on the K content of juice and wine. Fertilisation with Ca and Mg reduced the pH of juice significantly in the case of Meerlus. In contrast, Mg fertilisation increased the pH of juice significantly at Kersfontein. Lastly, fertilisation had no significant effect on the pH of the wine. The K content of the juice at Meerlus was significantly reduced by Canopy 3 in comparison with Canopy 1 and 2. However, in contrast with Canopy 1 and 3, Canopy 2 significantly increased the pH of juice at Meerlus. The K content of the juice at Kersfontein was significantly reduced by Canopy 1, compared to Canopy 2 and 3, with no significant effect on the pH of the juice. Canopy management had no significant effect on wine pH. It appears to be possible to reduce the pH of juice in the case of Cabernet franc/99R, situated on granite soils, by means of Ca and Mg fertilisation. Because Ca(OH)2 and MgS04 fertilisation increased the maturity of Cabernet Sauvignon/101-14 Mgt grapes, it was impossible to evaluate the effect of fertilisation on the pH of juice at Kersfontein. The general phenomenon that a high canopy density results in a high pH of juice and wine, was not observed in this field trial. The possible reasons for this were the low canopy density of the control plots, as well as the difference in maturity between canopy management treatments. / AFRIKAANSE OPSOMMING: In 'n poging om die pH van sap en wyn te verlaag, is die effek van verskillende bemesting- en lowerbestuursfaktore in 'n veldproef geêvalueer. Bemesting het bestaan uit geen, CaS04, Ca(OH)2 en MgS04 toediennings. Lowerbestuur was: suier tot twee lote per draer, tip, vertikale lootposisionering, verwydering van sylote en geel blare in trossone (Lower 1); suier tot drie lote per draer, top en vertikale lootposisionering (Lower 2); top en vertikale lootposisionering met geen suier nie (Lower 3). Die veldproef is op twee plase nl. Meerlus en Kersfontein, in die Paardeberg omgewing uitgevoer. Die wingerd by Meerlus was Cabernet franc/R99 met 'n hoë lowerdigtheid en goeie wortelverspreiding, wat op 'n sandleemgrond van graniet oorsprong met In lae ondergrond-pH en hoë K-inhoud gevestig is. Die wingerd by Kersfontein het bestaan uit Cabernet Sauvignon/101-14 Mgt met 'n laer lowerdigtheid en swakker wortelverspreiding, wat op In sandleemgrond van graniet oorsprong met In deurgaans lae grond-pH en baie hoë K-inhoud gevestig is. Bemesting het geen betekenisvolle invloed op die K-inhoud van sap en wyn gehad nie. By Meerlus het Ca- en Mg-bemesting egter die pH van sap betekenisvol verlaag. In teenstelling hiermee het Mg-bemesting die sap-ph by Kersfontein betekenisvol verhoog. Bemesting het verder geen betekenisvolle invloed op die pH van wyn gehad nie. Lower 3 het die K-inhoud van sap by Meerlus betekenisvol verlaag in vergelyking met Lower 1 en Lower 2. By Kersfontein was die K-inhoud van sap by Lower 1 betekenisvollaer as by Lower 2 en Lower 3. Teenoor Lower 1 en Lower 3 het Lower 2 'n betekenisvol hoër sap-pH by Meerlus tot gevolg gehad. Lowerbehandelings het egter geen betekenisvolle invloed op die pH van wyn gehad nie. Die moontlikheid bestaan dus om die sap-pH van Cabernet franc/R99 op granietgrond betekenisvol m.b.v. Ca- en Mg-bemesting te verlaag. Aangesien Ca(OH)2- en MgS04- bemesting die rypheidsgraad van Cabernet Sauvignon/101-14 Mgt se druiwe betekenisvol verhoog het, was dit onmoontlik om die effek van bemesting op sap-pH by Kersfontein te evalueer. Die algemene verskynsel dat 'n hoë lowerdigtheid tot hoë pH's in sap en wyn lei, is nie in die proef ondervind nie. Die lae lowerdigtheid van die kontrole persele en die verskil in rypheidsgraad tussen lowerbehandelings kan moontlik as rede hiervoor aangevoer word.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais, Florianópolis, 2009. / Made available in DSpace on 2012-10-24T20:45:59Z (GMT). No. of bitstreams: 1 267503.pdf: 1118454 bytes, checksum: 7fe62f8046bba8b89ab866da76b52d6e (MD5)

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Recursos Genéticos Vegetais. / Made available in DSpace on 2012-10-22T07:53:56Z (GMT). No. of bitstreams: 1 230683.pdf: 2623029 bytes, checksum: b36c5493a0261d321c7102b33c3cb743 (MD5) / No Brasil, a vitivinicultura está relacionada, principalmente, com os Estados da Região Sul. Em Santa Catarina estão envolvidas 2.000 famílias com a uva e seus derivados, gerando 18.430 empregos diretos nos 4.600 ha ocupados com a atividade - tradicional nas regiões do Vale do Rio do Peixe e de Urussanga. No Estado, 75% das uvas produzidas destinam-se a vinificação. A região de São Joaquim, em Santa Catarina, tem se mostrado favorável à produção de vinhos finos e vem despertando grande interesse de empreendedores na atividade. As variedades Cabernet Sauvignon, Chardonnay e Pinot Noir apresentam-se promissoras em São Joaquim. Os vinhedos Quinta da Neve na Lomba Seca foram cultivados em meia encosta, apresentando solos do tipo Cambissolos, mais profundos, melhor drenados e de baixa fertilidade, proporcionando condições favoráveis ao cultivo de videiras. As partes mais baixas do plantio propiciaram a ocorrência de geadas. O clima vitícola da Lomba Seca, em São Joaquim, apresentou clima mais seco durante a maturação das uvas. A Cabernet Sauvignon foi a variedade que mais necessitou de somas térmicas para completar a maturação, seguida pelas videiras de Chardonnay e de Pinot Noir. Definindo assim, tanto pelo Graus-Dia de Winkler como pelo Índice Heliotérmico de Huglin, uma escala para as 3 variedades, sendo a Pinot Noir a de menor e a Cabernet Sauvignon de maior exigência em necessidade térmica. Os vinhos microvinificados de Cabernet Sauvignon e Pinot Noir demonstraram cor intensa, riqueza em antocianinas, taninos e polifenóis totais. A Chardonnay apresentou com cor intensa e límpida, com menor teor de polifenóis totais, característica genética das viníferas brancas. As analises químicas mostraram que são vinhos mais alcoólicos e ácidos. Estas características, somadas a cor intensa, os taninos e as antocianinas dos vinhos, demarcam 'um produto típico' de qualidade determinada pelas condições de 'clima-solo-variedades' das regiões de altitudes.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Ciência dos Alimentos. / Made available in DSpace on 2012-10-22T09:23:22Z (GMT). No. of bitstreams: 1 226349.pdf: 981797 bytes, checksum: 8b11491f9077720be52865d3f7b48d93 (MD5)

In 2009 and 2010 a split, split, split plot experiment with training system, VSP or Smart-Dyson Ballerina (main plot), N, 0 or 33.6 kg/ha (split), crop level, 14.0, 18.7, or 23.4 clusters/m/canopy (split), clone, Cabernet Franc 1,4, 8 and 214 treatments with five replications were established in Union County, Illinois on mature vines. The Smart-Dyson Ballerina training system produced a Ravaz index that was 89% and 28% bigger compared to the VSP respectively in 2009 and 2010. In 2009, the Smart-Dyson Ballerina produced a 80% bigger yield than VSP and in 2010 yield was also larger, but influenced by both training system and crop level. Maintaining a balanced vineyard can increase profit for the grower by up to $6,356.87/ha.

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais, Florianópolis, 2017. / Made available in DSpace on 2017-10-03T04:19:53Z (GMT). No. of bitstreams: 1 348737.pdf: 1112619 bytes, checksum: 3ee59e1ba21387c2084ac97ac782eb10 (MD5) Previous issue date: 2017 / A Cabernet Sauvignon, uma das variedades de videira (Vitis vinifera L.) com maior área cultivada em regiões de elevada altitude de Santa Catarina, apresenta potencial para produção de vinhos de qualidade em regiões superiores a 900 m de altitude. No entanto, ela vem apresentando menor produtividade em São Joaquim em relação a regiões de menor altitude, principalmente em Campo Belo do Sul. Diante do exposto, objetivou-se com este trabalho avaliar os teores de clorofila, fluorescência da clorofila e o acúmulo de reservas da variedade Cabernet Sauvignon em duas regiões de altitude de Santa Catarina, São Joaquim (1.400 m) e Campo Belo do Sul (950 m), a fim de elucidar as respostas fisiológicas da variedade às condições climáticas de seu local de cultivo. As áreas experimentais estão na Vinícola Abreu Garcia, em Campo Belo do Sul e na Estação experimental da Epagri, em São Joaquim. Foram coletadas 12 folhas de Cabernet Sauvignon em ambos locais nos períodos da colheita e queda das folhas para realização das análises de fluorescência em folhas adaptadas ao escuro e quantificação dos teores de clorofila. Foram realizadas curvas de resposta à luz em cinco folhas em condições de luz natural, em delineamento inteiramente casualizado, com 5 repetições por local. Também foi realizada a avaliação de carboidratos e amido em ramos e gemas de Cabernet Sauvignon, coletadas nos períodos de colheita, queda das folhas e poda, em ambos locais. Para isso foi coletado um ramo por planta de quatro plantas em cada época e local. Os teores de clorofila nas folhas de Cabernet Sauvignon foram mais elevados na região de maior altitude no período da colheita. Na queda das folhas não houve diferença entre os locais. Além disso, houve uma diminuição dos valores de clorofila entre as épocas de colheita e queda das folhas em ambos locais. Os resultados de fluorescência máxima e rendimento quântico potencial foram superiores na região de maior altitude. A taxa de transporte de elétrons máxima foi mais elevada em São Joaquim no período da colheita e em Campo Belo do Sul na queda das folhas. Na colheita, a DFFFAsat foi superior em São Joaquim e na queda das folhas foi superior em Campo Belo do Sul. No período da colheita o teor de carboidratos nos ramos de Cabernet Sauvignon em São Joaquim foi superior ao encontrado em Campo Belo do Sul. Na queda das folhas o valor foi similar entre os locais. Não foram observadas diferenças significativas para valores de carboidratos nos ramos no período da poda. Os teores de carboidratos nos ramos em Campo Belo do Sul foram superiores no período da poda. Em São Joaquim, os maiores valores foram observados na colheita e na poda. Os teores de carboidratos nas gemas não diferiram entre as regiões em nenhum dos períodos avaliados. Os maiores teores de carboidrato nas gemas foram observados nos períodos da colheita e da poda em ambos os locais. Nas folhas os teores foram superiores colheita em Campo Belo do Sul, em ambos períodos. Os teores de carboidratos nas folhas nas duas regiões foram semelhantes em ambos períodos avaliados. Em todas as épocas os teores de amido nos ramos foram similares para Campo Belo do Sul e São Joaquim. O teor de amido nos ramos na região de Campo Belo do Sul foi superior no período da poda. Na região de São Joaquim não houve diferença entre as épocas. Não foram observadas diferenças nos teores de amido em gemas entre os locais em nenhum dos períodos. A concentração de amido em gemas de Cabernet Sauvignon foi superior no período da poda em ambas regiões. Na colheita e na queda das folhas os valores de amido foram superiores em Campo Belo do Sul. Os teores de amido nas folhas foram superiores no período da colheita em Campo Belo do Sul. Em São Joaquim não houve diferença entre os períodos. Em Campo Belo do Sul, as maiores concentrações de carboidratos e amido em ramos e gemas foram observadas no período da poda. Em São Joaquim as quantidades foram semelhantes na colheita e na poda, sendo superiores em relação a queda das folhas. Os resultados obtidos nesse estudo demonstram boas condições fotossintéticas das folhas e bom acúmulo de reservas em plantas de Cabernet Sauvignon em São Joaquim. Tais resultados não explicam a ocorrência de menor produtividade da variedade Cabernet Sauvignon nesse local. No entanto, outros fatores podem afetar a produtividade da videira, por isso, são necessários estudos adicionais a fim de compreender as diferenças produtivas entre as regiões.<br> / Abstract : Cabernet Sauvignon, one of the grape varieties (Vitis vinifera L.) with the largest cultivated area in Santa Catarina high altitude regions, has the potential to produce quality wines in regions above 900 m of altitude. However, it has showed lower productivity in São Joaquim in relation to lower altitude regions, mainly in Campo Belo do Sul. In view of the above, the objective of this study was to evaluate the chlorophyll, chlorophyll fluorescence and reserves accumulation of the Cabernet Sauvignon variety in two highland regions of Santa Catarina, São Joaquim (1,400 m) and Campo Belo do Sul (950 m), in order to elucidate the physiological responses of the variety to the climatic conditions of its cultivation site. The experimental areas are at Abreu Garcia Winery, in Campo Belo do Sul and at the experimental station of Epagri, in São Joaquim. Twelve leaves of Cabernet Sauvignon were collected at both sites during the harvest and leaf fall periods to perform the fluorescence analyzes on leaves adapted to the dark and quantify the levels of chlorophyll. Light response curves were performed in five field leaves, in a completely randomized design, with 5 replications per site. The evaluation of carbohydrates and starch in Cabernet Sauvignon twigs and buds collected during the harvesting, leaf fall and pruning periods was also carried out at both sites. For this, a branch per plant of four plants was collected in each season and place. The levels of chlorophyll in the Cabernet Sauvignon leaves were highest in the region of higher altitude at harvest time. In the fall of the leaves no differences between the sites were observed. In addition, there was a decrease in the values of chlorophyll between harvesting time and leaves fall at both sites. The results of maximum fluorescence and potential quantum yield were higher at higher altitude region. The maximum electron transport rate was highest at São Joaquim in the harvest period and at Campo Belo do Sul in leaves fall. At harvest, PPFDsat was higher in São Joaquim and at leaves fall was higher in Campo Belo do Sul. In the harvest period, the carbohydrate content in the Cabernet Sauvignon branches in São Joaquim was higher than that found in Campo Belo do Sul. In the leaves fall the value was similar between the sites. No significant differences were observed for carbohydrate values in the pruning. Carbohydrate contents in the branches of Campo Belo do Sul were higher during the pruning period. In São Joaquim, the highest values were observed at harvest and pruning. The carbohydrate content in the buds did not differ between the two regions in any of the evaluated periods. The highest carbohydrate contents in the buds were observed during harvesting and pruning periods at both sites. In leaves the contents were highest at harvest in Campo Belo do Sul in both periods. Carbohydrate contents in leaves in both regions were similar in both evaluated periods. In all seasons the starch contents in the branches were similar to Campo Belo do Sul and São Joaquim. The starch content in the branches in the Campo Belo do Sul region was higher during the pruning period. In the region of São Joaquim there was no difference between the seasons. No differences were observed in the starch contents in buds between the sites in any of the periods. The concentration of starch in Cabernet Sauvignon buds was higher during the pruning period in both regions. In the harvest and the fall of the leaves, the starch values were higher in Campo Belo do Sul. The leaf starch content was higher during the harvest period in Campo Belo do Sul. In São Joaquim there was no difference between the periods. In Campo Belo do Sul, the highest concentrations of carbohydrates and starch in branches and buds were observed during the pruning period. In São Joaquim, the amounts were similar in the harvest and in the pruning, being superior in relation to the fall of the leaves. The results obtained in this study demonstrate good photosynthetic conditions of the leaves and good accumulation of reserves in Cabernet Sauvignon plants in São Joaquim. These results do not explain the occurrence of lower productivity of the Cabernet Sauvignon variety at this location. However, other factors may affect vine productivity, so additional studies are needed to understand the productive differences between regions.