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Comportamento vitícola da variedade Cabernet Sauvignon (Vitis vinifera L.) em dois municípios do Planalto Sul CatarinenseGavioli, Olavo 25 October 2012 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias, Programa de Pós-Graduação em Recursos Genéticos Vegetais, Florianópolis, 2011 / Made available in DSpace on 2012-10-25T20:02:30Z (GMT). No. of bitstreams: 1
292908.pdf: 325079 bytes, checksum: 1fcba7f4da1365c0df92bff81a28bd0e (MD5) / A vitivinicultura no Estado de Santa Catarina tem se destacado, principalmente, nas regiões de altitude elevada como produtora de uvas viníferas para a elaboração de vinhos finos. Estas regiões possuem características próprias e distintas das tradicionais regiões produtoras brasileiras. As variáveis climáticas deste novo pólo vitícola, permitem a maturação fisiológica completa das uvas, resultando em produtos de alta qualidade e com uma forte identidade regional. Porém, existe pouco conhecimento técnico-científico a respeito destas novas regiões de altitude. Diante desta situação, este trabalho tem por objetivo caracterizar o comportamento vitícola da variedade Cabernet Sauvignon, durante o ciclo 2008/2009, nos municípios de Campo Belo do Sul (900m) e São Joaquim (1.293m), localizados no Planalto Sul Catarinense. Durante todo o ciclo foram monitoradas as variáveis climáticas: temperatura, radiação solar e precipitação, concomitantemente com análises semanais da composição fisico-química das uvas. Os resultados indicam que as duas localidades estudadas apresentam condições climáticas favoráveis à atividade da vitivinicultura. A média das temperaturas máxima, média e mínima em São Joaquim foram, respectivamente, de 23,1°C, 15,1°C e 9,9°C e em Campo Belo do Sul de 26,5°C, 19,5°C e 15,3°C. As variações de temperatura influenciaram diretamente o ciclo fenológico da videira, resultando em diferenças entre as duas regiões. Em Campo Belo do Sul, o clima vitícola é classificado como ameno (1.668 à 1.944 GD), segundo o Índice de Winkler e, em São Joaquim, foi classificado como frio (< 1.389 GD). A precipitação pluviométrica foi semelhante nas duas regiões. Em São Joaquim, o volume de precipitação foi de 999,8 mm, e em Campo Belo do Sul, este total foi de 870,0 mm. Estes volumes podem ser considerados elevados para o cultivo da videira. Verificou-se que a radiação fotossinteticamente ativa (RFA) e a radiação global (Rg) apresentaram comportamento similar durante o período de avaliação. Foi possível observar que em todos os estádios fenológicos, tanto em São Joaquim como em Campo Belo do Sul, apresentaram valores de RFA suficientes para que as plantas realizem a fotossíntese. O crescimento dos ramos reduziu significativamente a partir do início da mudança de cor das bagas e paralisando durante a fase inicial de maturação. No vinhedo localizado em Campo Belo do Sul, os ramos principais apresentaram comprimento médio de 217,3cm quando cessaram o crescimento e em São Joaquim, o crescimento médio dos ramos alcançou 266,3cm. No início da maturação em Campo Belo do Sul, as bagas apresentavam cerca de 16ºBrix. Com a evolução da maturação estes compostos foram se acumulando nas bagas, sendo que na colheita, o teor de sólidos solúveis totais foi de 23 ºBrix. Em São Joaquim, a maturação iniciou com 14,7 ºBrix, sendo as uvas colhidas com média de 23,9 ºBrix. A acidez total titulável apresentou padrão de redução nos valores durante a evolução da maturação. Para o vinhedo de Campo Belo do Sul, inicialmente, a acidez total avaliada nas bagas estava próxima a 250meq/l, sendo que ao final do período de maturação, os valores se estabilizaram em torno de 83meq/l. Em São Joaquim, iniciou com 280meq/l e, no momento da colheita, a uva apresentava aproximadamente 100 meq/l. O cultivo da variedade Cabernet Sauvignon, em ambas as regiões estudadas possibilita a obtenção de uvas de boa qualidade para a elaboração de vinhos.
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Refining Fruit-Zone Leaf Removal for Red-Fruited Bordeaux Grape Varieties Grown in a Humid EnvironmentHickey, Cain C. 30 June 2016 (has links)
Current fruit-zone management recommendation in the eastern US aims for 1-2 basal shoot leaf layers after fruit set to limit fungal disease and sunburn incidence, and prevent extreme heating of grapes. The goal of this work was to assess if fruit-zone leaf removal to an uncommonly greater extent, and/or at an earlier phenological stage, would favorably alter yield components or fruit composition in three popularly grown, red-fruited, Bordeaux varieties – Cabernet franc, Petit Verdot, and Cabernet Sauvignon. Pre-bloom leaf removal to various extents reduced crop yield by 41-78% when compared to no leaf removal across seasons and varieties. Pre-bloom leaf removal implementation in consecutive seasons tended to further reduce crop yield components compared to implementation in the first year. Pre-bloom leaf removal tended to reduce cluster compactness and bunch rot incidence when compared to post-fruit set and no leaf removal. Basal leaf removal to the greatest extents inconsistently reduced soluble solids and titratable acidity across varieties and seasons. Pre-bloom and post-fruit set leaf removal to the greatest extent consistently increased total grape phenolics and anthocyanins compared to no leaf removal in Cabernet Sauvignon, but inconsistently increased total grape phenolics compared to no leaf removal in Cabernet franc and Petit Verdot. Basal leaf removal to the greatest extents tended to increase the synthesis and degradation of carotenoids more consistently than no leaf removal, and this was particularly true for zeaxanthin. Petit Verdot and Cabernet franc wine color and aroma were inconsistently distinguishable between leaf removal treatments, and color intensity was rated higher in wines made with fruit from pre-bloom leaf removal compared to modest post fruit-set leaf removal plots. Waiting until after fruit set to remove fruit-zone leaves maintained crop yield and offered comparable improvements in fruit composition to pre-bloom leaf removal. Pre-bloom leaf removal of no more than four leaves is recommended to limit crop yield reduction, and modestly improve fruit composition. This work showed that fruit-zone leaf removal does not need to be conservative in the eastern US, particularly because the climate does not appear to be detrimental to fruit composition, and open fruit-zones reduce grape fungal disease incidence. / Ph. D.
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Winemaking practices affecting glutathione concentrations in white wineKritzinger, Engela Cornelia 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Glutathione (GSH), a tripeptide consisting of glutamate, cysteine and glycine, is the most ubiquitous
non‐protein intracellular thiol in a large variety of organisms, including plants, animals and fungi. The
thiol moiety of the cysteine residue confers unique redox and nucleophilic properties. In plant cells,
GSH fulfils an indispensible role in the antioxidant system, sulphur metabolism and detoxification of
xenobiotics.
Upon grape crushing, GSH is extracted into the juice where it exerts several protective effects
during the vinification process. In must, it reacts with oxidized phenolic compounds to form the
colourless grape reaction product (GRP) which limits must browning to a certain extent. During wine
ageing, GSH impedes the decrease of important aroma compounds, including certain esters, terpenes
and volatile thiols, while at the same time preventing the development of atypical ageing off‐flavours.
GSH may also inhibit the yellowing of wine during ageing. It is thus evident that elevated GSH levels in
wine, in particular white wine which is more sensitive to oxidation, may be highly valuable for wine
quality.
The reductive crushing and pressing of white grape varieties, which limits oxidation and the
consequent incorporation of GSH into GRP, promotes higher GSH levels in the juice. The reductive
handling of juice also limits the formation of oxidized glutathione (GSSG). However, during alcoholic
fermentation and maturation, levels generally decrease as a result of assimilation by the yeast
Saccharomyces cerevisiae, and inevitable oxidation that takes place during the vinification process. The
principal focus of this study was to gain a better understanding of the fate of glutathione during
alcoholic fermentation and to establish whether certain oenological applications could result in elevated
wine GSH levels. The application studied, included choice of yeast strain, extended lees contact,
nitrogen supplementation and supplementation with glutathione enriched inactive dry yeast
preparations (GHS‐IDYs). In addition, the need for a rapid analytical method for the simultaneous
quantification of both GSH and GSSG in must and wine which does not involve derivatization or require
extensive sample preparation, led to the development of a novel UPLC‐MS/MS method. The method
was also employed to determine intracellular GSH and GSSG contents of the yeast S. cerevisiae and was
studied for the first time in winemaking conditions.
It was shown that the GSH levels fluctuated during alcoholic fermentation, suggesting the uptake
and release by yeast. At the end of alcoholic fermentation, levels were generally lower than those
initially present in grape juice, but in some cases, concentration increases were also observed. This
finding indicates that, in some cases, endogenously‐produced GSH may be secreted into must during
alcoholic fermentation, contributing to higher GSH levels in wine. Albeit small, significant differences in
GSH content could be seen in wines fermented with different yeast strains, implying that yeast strain
may to a certain extent influence wine GSH levels. While the effects of lees ageing and nitrogen
supplementation seem to be insignificant in contributing to higher GSH levels in wine, the
supplementation of must with GSH‐IDYs could result in increased wine GSH levels, provided the
supplementation is done early during fermentation. This study has broadened our knowledge of several
oenological factors, influencing GSH levels in wine and provided a new baseline for future research
studies. / AFRIKAANSE OPSOMMING: Glutatioon (GSH), ’n tripeptied bestaande uit glutamaat, sisteïen en glisien, is die mees algemene nieproteïenagtige
intrasellulêre tiool in ‘n wye verskeidenheid organismes, insluitende plante, diere en
fungi. Die tioolfunksiegedeelte van die sisteïenresidu verleen unieke redoks‐ en nukleofiliese
eienskappe. GSH vervul ‘n onmisbare rol in die antioksidantsisteem, swaelmetabolisme en die
ontgiftiging van xenobiotika in plantselle.
Tydens die maal van druiwe word glutatioon in die sap geëkstraeer waar dit verskeie beskermende
effekte tydens die wynbereidingsproses uitoefen. GSH reageer met geöksideerde fenoliese verbindings
om die kleurlose druifreaksieproduk (DRP) te vorm wat die verbruining van mos in ‘n sekere mate
beperk. GSH verminder ook die afname van belangrike aromaverbindings tydens wynveroudering,
insluitende sekere esters, terpene en vlugtige tiole, terwyl dit terselfdertyd die vorming van atipiese
verouderingswangeure belemmer. So ook kan GSH die vergeling van wyn tydens veroudering inhibeer.
Dit is dus voor die hand liggend that verhoogde GSH‐vlakke in wyn, in die besonder witwyn, wat meer
oksidasie‐sensitief is, van waarde kan wees vir wynkwaliteit.
Die reduktiewe maal en pers van witdruifvariëteite wat oksidasie en gevolglike inkorporasie van
GSH in DRP beperk, bevorder hoër GSH‐vlakke in sap. So ook beperk die reduktiewe behandeling van
sap die vorming van geoksideerde glutatioon (GSSG). Gedurende alkoholiese gisting en veroudering
neem GSH‐vlakke egter af as gevolg van assimilasie deur die gis, Saccaromyces cerevisiae, asook
onvermydelike oksidasie wat gedurende die wynbereidingsproses plaasvind. Die hooffokus van die
studie was om ‘n beter begrip van die lot van glutatioon tydens alkoholiese gisting te verkry en om vas
te stel of sekere wynkundige praktyke verhoogde GSH‐vlakke in wyn tot gevolg kan hê. Die studie het
gisraskeuse, verlengde gismoerkontak, stikstofaanvulling en aanvulling met glutatioon‐verrykte,
onaktiewe droëgis ingesluit. Daarbenewens het die behoefte aan ‘n vinnige analitiese metode vir die
gelyktydige kwantifisering van sowel GSH as GSSG in mos en wyn wat nie derivatisering of uitgebreide
monstervoorbereiding vereis nie, gelei tot die ontwikkeling van ‘n nuwe UPLC‐MS/MS metode. Hierdie
metode is ook gebruik om die intrasellulêre GSH‐ en GSSG‐inhoud van die gis S. cerevisiae te bepaal wat
vir die eerste keer in wynbereiding bestudeer is.
Daar is bewys dat GSH‐vlakke tydens alkolholiese gisting fluktueer, wat dui op die opname en
vrystelling daarvan deur die gis. Die vlakke aan die einde van alkoholiese gisting was oor die algemeen
laer as vlakke aanvanklik teenwoordig in die sap. In sommige gevalle is konsentrasietoenames egter ook
waargeneem. Hierdie bevinding dui daarop dat intrasellulêr‐vervaardige GSH, in sommige gevalle, in die
mos uitgeskei kan word, wat tot hoër GSH‐vlakke in wyn lei. Klein, dog beduidende verskille in GSHinhoud
is waargeneem in wyne wat met verskillende gisrasse berei is, wat daarop dui dat gisras in ‘n
sekere mate die GSH‐vlakke in wyn kan beïnvloed. Alhoewel die effek van gismoerveroudering en
stikstofaanvulling onbeduidend is, kan die aanvulling van mos met glutatioon‐verrykte, onaktiewe
droëgis tot verhoogde GSH‐vlakke in wyn lei, mits die aanvulling vroeg tydens alkoholiese gisting gedoen
word. Hierdie studie verbreed ons kennis van verskeie wynkundige praktyke wat GSH‐vlakke in wyn
beïnvloed en vorm ‘n nuwe basis vir toekomstige navorsingstudies.
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Evaluation of parameters to determine optimum ripeness in Cabernet Sauvignon grapes in relation to wine qualityBotes, Matthys Petrus 03 1900 (has links)
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.
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Effect of climate and soil water status on Cabernet Sauvignon (Vitis vinifera L.) grapevines in the Swartland region with special reference to sugar loading and anthocyanin biosynthesisMehmel, Tara Olivia, Van Heerden, Tara Olivia 23 November 2010 (has links)
Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosach, 2010. / ENGLISH ABSTRACT: Cabernet Sauvignon, the most planted red wine cultivar in South Africa, is prone to vigorous
growth with low yields. The aim of the study was to describe how Cabernet Sauvignon
grapevines react to climate and irrigation within the Swartland region. Such knowledge would
assist growers in decisions regarding long term as well as short term cultivation practices. This
study was part of a larger project carried out by the Infruitec-Nietvoorbij institute of the
Agricultural Research Council at Stellenbosch to determine effects of soil type and climate on
yield and wine quality of Cabernet Sauvignon. The larger project was carried out in selected
grape growing regions, i.e. Stellenbosch, Swartland, Lower Olifants River and Lower Orange
River.
Due to the proximity to the Atlantic Ocean, the study area in the Swartland region could
be divided into two climatic regions for viticulture. Grapevines near Philadelphia closer to the
ocean experienced less water constraints compared to those further inland near Wellington.
Variation in stem water potential could also be related to soil water matric potential. Climate
tended to have a more pronounced effect on the grapevine response to water constraints
further inland than closer to the ocean. Vegetative growth, berry size and yield depended on
water constraints experienced by the grapevines. In the warmer climate, severe constraints
reduced yield.
In the warmer climate, grapes started to ripen earlier than those in the cooler climate.
Sugar concentration (mg/mL) was highest where grapevines experienced moderate water
constraints. These seemingly balanced grapevines had the highest sugar accumulation,
probably due to optimum photosynthesis and carbohydrate utilization. Low water constraints
increased vegetative growth which could have been a sink for sugar loading. In addition to
sugar loading, degree Balling (°B) increases could also have been due to a concentration effect
where water constraints reduced berry volume. Therefore, °B is probably not a representative
indicator of grapevine functioning.
Anthocyanin biosynthesis, as quantified on a per berry basis, showed that sugar and
anthocyanin could be co-regulated, with anthocyanin biosynthesis reaching a plateau when the
sugar content per berry reached 200 mg/mL to 220 mg/mL. At véraison, the most intense grape
colour occurred where grapevines experienced moderate water constraints, i.e. single drip line
at Wellington and no irrigation at Philadelphia. However, at harvest grapes from the cooler
climate tended to have more intense colour and higher phenolics, indicating that lower
temperatures favoured anthocyanin biosynthesis. These results supported earlier findings that
grapevine water status influences berry volume and dynamics of berry ripening.
Water constraints tended to increase sensorial wine colour intensity, as well as wine
fullness. Moderate water constraints at both localities resulted in the best sensorial wine quality.
Yet there were indications that too severe water constraints could be detrimental to wine quality. Irrigation can be used to manipulate grapevine growth in warmer climates, but might be less
effective in cooler climates. In warmer climates, moderate water constraints required to achieve
balanced grapevine functioning can be obtained with single drip irrigation, but this might not be
the case in cooler climates. / AFRIKAANSE OPSOMMING: Cabernet Sauvignon, die mees aangeplante rooiwynkultivar in Suid-Afrika, is geneig tot kragtige
groei met lae opbrengste. Die doelwit van hierdie studie was om te beskryf hoe Cabernet
Sauvignon-wingerdstokke reageer op klimaat en besproeiing in die Swartland-streek. Hierdie
kennis sal kwekers help wanneer hulle besluite moet neem oor langtermyn sowel as korttermyn
verbouingspraktyke. Hierdie studie was deel van ‘n groter projek deur die Infruitec-Nietvoorbij
Instituut van die Landbounavorsingsraad op Stellenbosch om die effekte van grondtipe en
klimaat op die opbrengs en wynkwaliteit van Cabernet Sauvignon te bepaal. Die groter projek is
in geselekteerde wingerdverbouingstreke uitgevoer, nl. Stellenbosch, Swartland, Benede
Olifantsrivier en Benede Oranjerivier.
As gevolg van die nabyheid daarvan aan die Atlantiese Oseaan kon die studiegebied in
die Swartland-streek in twee klimaatstreke vir wingerdbou verdeel word. Wingerdstokke by
Philadelphia, wat nader aan die oseaan is, het minder waterstremming ervaar as dié verder
binnelands naby Wellington. Veranderinge in stamwaterpotensiaal hou moontlik ook verband
met die grondwater- matrikspotensiaal. Klimaat het ‘n groter effek op die reaksie van die
wingerdstok op waterstremming verder binnelands as nader aan die oseaan. Vegetatiewe groei,
korrelgrootte en opbrengs was afhanklik van die waterstremminge wat deur die wingerdstokke
ervaar is. In die warmer klimaat het die ernstige stremminge opbrengs verminder.
In die warmer klimaat begin druiwe vroeër ryp word as in die koeler klimaat.
Suikerkonsentrasie (mg/ml) was die hoogste waar wingerde matige waterstremming ervaar het.
Hierdie skynbaar gebalanseerde wingerdstokke het die hoogste suikerakkumulasie vertoon,
moontlik as gevolg van optimum fotosintese en koolhidraatverbruik. Lae waterstremming het
vegetatiewe groei verhoog, wat ook ‘n vraagpunt vir suikerlading kon wees. Benewens
suikerlading kon verhogings in grade Balling (°B) ook moontlik aan ‘n konsentrasie-effek
toegeskryf word in terme waarvan waterstremming die korrelvolume verminder het. °B is dus
moontlik nie ‘n verteenwoordigende indikator van wingerdstokfunksionering nie.
Antosianienbiosintese, soos gekwantifiseer op ‘n per-korrel basis, het getoon dat suiker
en antosianien saam gereguleer kon word, en dat antosianienbiosintese ‘n plato bereik het
wanneer die suikerinhoud per korrel 200 mg/mL tot 220 mg/mL was. By deurslaan het die mees
intense druifkleur voorgekom waar die wingerdstokke matige waterstremming ervaar het, d.w.s.
enkel druplyn op Wellington en geen besproeiing op Philadelphia. Teen oes was die druiwe in
die koeler klimate egter geneig om meer intense kleur en meer fenole te bevat, wat aandui dat
laer temperature antosianienbiosintese bevoordeel. Hierdie resultate ondersteun vroeër
bevindings dat die waterstatus van die wingerdstok ‘n invloed op korrelvolume en die dinamika
van korrelrypwording het.
Waterstremming neig om die sensoriese wynkleurintensiteit te verhoog, asook die
volheid van die wyn. Matige waterstremming op beide liggings het aanleiding gegee tot die beste sensoriese wynkwaliteit. Tog was daar aanduidings dat waterstremming wat te straf was,
nadelig kon wees vir wynkwaliteit. Besproeiing kan gebruik word om wingerdgroei in warmer
klimate te manipuleer, maar is moontlik minder effektief in koeler klimate. In warmer klimate kan
die matige waterstremming wat benodig is vir gebalanseerde wingerdstokfunksionering, verkry
word deur enkel drupbesproeiing, maar dit is moontlik nie die geval in koeler klimate nie.
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Oxygen and sulphur dioxide additions to Sauvignon blanc : effect on must and wine compositionCoetzee, Carien 03 1900 (has links)
Thesis (MScAgric (Viticulture and Oenology))--University of Stellenbosch, 2011. / Includes bibliogaphy. / ENGLISH ABSTRACT: Sauvignon blanc wines have become increasingly popular in South Africa as it is a cultivar that can be
easily manipulated in the vineyard and cellar to produce a range of wine styles. These wines are usually
given aroma descriptors such as green pepper, grassy and asparagus; while other more tropical aromas
include passion fruit and guava. These aromas are thought to be mainly caused by methoxypyrazines
and volatile thiols. These compounds are known to be character impacting compounds of Sauvignon
blanc and are present in the grapes in the aromatic form (methoxypyrazines) or as non‐aromatic
precursors (thiols) that can be released by the yeast during fermentation. Other aroma compounds such
as esters, higher alcohols, fatty acids and monoterpenes are compounds that could potentially influence
the aroma bouquet of a wine significantly. These aroma compounds exist either as precursors in the
grapes (monoterpenes) or arise due to yeast metabolism during fermentation (esters, higher alcohols,
fatty acids) and often display fruity, floral and pleasant aromas.
In the cellar, winemaking practices can be manipulated to a certain extent to achieve the desired wine
style. Winemaking tools such as temperature, skin contact, pressing conditions, oxygen (O2), sulphur
dioxide (SO2) and yeast strain are only a few factors influencing the outcome of a wine. In general, South
African winemakers maintain a very reductive environment during Sauvignon blanc wine production by
using inert gasses, thereby causing the production costs to increase. There is sufficient evidence to
support the reductive handling of white wine, however there seems to be a lack of information as to
why the must should be treated reductively before fermentation. The over all goal of this study was thus
to investigate the effect of different O2 and SO2 additions to Sauvignon blanc must before settling,
specifically focussing on the typical aroma compounds often found in these wines.
Chapter 2 gives an overview of the oxidation reactions occurring in must (enzymatic oxidation) and wine
(chemical oxidation). This chapter also reports the origin of the specific Sauvignon blanc aroma
compounds and their reaction to different must and wine treatments with a focus on oxidation. Chapter
3 reports research results focussing on the effect of the different must treatments on the character
impacting compounds of Sauvignon blanc wines, specifically the methoxypyrazines and the volatile
thiols. The effect of the treatments on the polyphenols and glutathione content in the must and wine
was also investigated. Oxidation in the absence of SO2 led to a decrease in glutathione and certain
phenolic compounds in the must. In general, volatile thiols were protected against oxidation by SO2,
even when O2 was present in the must. Methoxypyrazines concentrations were not significantly
influenced by the treatments. Chapter 4 elucidates the effect of the treatments on other yeast and
grape derived aroma compounds often found in Sauvignon blanc wines, such as the esters, higher
alcohols, fatty acids and monoterpenes. In general, the effect of SO2 seemed to have the greatest
influence on the produced aroma compounds.
The results reported in this thesis could possibly change the way South African Sauvignon blanc musts
are handled in future during the winemaking process. It is clear that O2 and SO2 management in the
cellar is of critical importance for the winemaker to produce wines of high quality. Future work is
important to fully understand the mechanisms and evolution of important aroma compounds of
Sauvignon blanc wines during the winemaking process. / AFRIKAANSE OPSOMMING: Sauvignon blanc wyn aroma word gewoonlik beskryf met terme soos groen rissie, grasagtig en aspersie
terwyl ander tropiese aromas soos grenadella en koejawel ook dikwels voorkom. Die manipulasie van
Sauvignon blanc in die wingerd en in die kelder tydens wynmaak, gee die wynprodusent die vryheid om
‘n wye reeks wyn style te produseer. Dit maak Sauvignon blanc baie populêr in die Suid‐Afrikaanse
wynindustrie. Die bogenoemde aromas word waargeneem in die wyn as gevolg van die
teenwoordigheid van sekere aroma komponente genaamd metoksipirasiene en vlugtige tiole. Hierdie
komponente lewer ‘n unieke bydrae tot die aroma samestelling van Sauvignon blanc wyne en kom voor
in die druiwe in die aromatiese vorm (metoksipirasiene) of as nie‐aromatiese voorlopers (tiole) wat
tydens alkoholiese fermentasie deur die gis vrygestel kan word. Komponente soos esters, hoër alkohole,
vetsure en monoterpene kan ook ‘n potensiële bydra lewer tot die algehele aroma van Sauvignon blanc
wyne en kom voor in die druiwe (monoterpene) of ontstaan as gevolg van gis metabolisme gedurende
alkoholiese fermentasie (esters, hoër alkohole, vetsure). Hierdie geur komponente word dikwels beskryf
as vrugtig, blomagtig en oor die algemeen aangenaam.
Tydens wynmaak kan die wyn tot ‘n mate gemanipuleer word om ‘n spesifieke wynstyl te bekom.
Hulpmiddels soos temperatuur, dopkontak, pers omstandighede, suurstof (O2), swawel dioksied (SO2) en
gisras is slegs ‘n paar faktore wat die algemene uitkoms van ‘n wyn kan beïnvloed. Oor die algemeen
word Sauvignon blanc in Suid‐Afrika baie reduktief behandel tydens wynbereiding. Dit vereis sekere
hulpmiddels, soos die gebruik van inerte gas, wat die produksiekoste dikwels verhoog. Navorsing
ondersteun die reduktiewe behandeling van wit wyn, maar dit wil voorkom asof daar ‘n tekort aan
navorsing is wat die reduktiewe behandeling van die sap voor fermentasie regverdig. Die algemene doel
van die studie is dus om die effek van verskillende O2 en SO2 byvoegings tot Sauvignon blanc sap (voor
afsak) te ondersoek met die fokus op die tipiese aroma komponente wat in die wyn voorkom.
Hoofstuk 2 lewer ‘n algemene oorsig van die tipes oksidasie reaksies wat voorkom in sap (ensiematiese
oksidasie) en wyn (chemiese oksidasie). Spesifieke Sauvignon blanc aroma komponente word ook
ondersoek in terme van die oorsprong van die komponente asook die reaksie wat plaasvind met
verskillende mos en wyn behandelings, met ‘n fokus op oksidasie. In hoofstuk 3 word die effek van die
verskillende mos behandelings op tipiese Sauvignon blanc aroma komponente, spesifiek
metoksipirasiene en vlugtige tiole, ondersoek. Die effek van die behandelings op die polifenole en
glutatioon inhoud in die mos en wyn word ook gerapporteer. Oksidasie van die sap in die afwesigheid
van SO2, het ‘n afname in glutatioon en sekere polifenol konsentrasies veroorsaak. Dit wil voorkom asof
die produksie van vlugtige tiole oor die algemeen beskerm word teen oksidasie indien daar genoegsame
SO2 teenwoordig is. Hierdie effek word ondervind selfs as die sap met suursof versadig word. Die effek
van die behandelings op die konsentrasies van metoksipirasiene was nie beduidend nie. Hoofstuk 4
rapporteer die effek van die behandelings op ander aroma komponente soos esters, hoër alkohole,
vetsure en monoterpene. Oor die algemeen wil dit voorkom asof die effek van SO2 beduidend was en
waarskynlik die grootste invloed op die produksie van hierdie aroma komponente het.
Na aanleiding van die resultate bevind in hierdie tesis, is daar ‘n moontlikheid dat die manier waarop
Sauvignon blanc wyne geproduseer word in Suid‐Afrika, moontlik kan verander in die toekoms. Vir die
wynmaker om hoë kwaliteit Sauvignon blanc wyne te produseer, is O2 en SO2 bestuur in die kelder van
kardinale belang. Verdere navorsing moet steeds gedoen word om die meganisme en evolusie van
belangrike aroma komponente in Sauvignon blanc wyne tydens die wynmaakproses, ten volle te
verstaan.
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Composición química y perfil sensorial de vinos de crianza de la D.O. JumillaRodríguez Rodríguez, Pedro 11 March 2011 (has links)
Se ha estudiado el efecto del volumen de la barrica, el tostado y origen de la madera de roble y la tonelería sobre los parámetros cromáticos, aromáticos, sensoriales y nutricionales de vinos de Monastrell, Cabernet Sauvignon y Petit Verdot elaborados en la D.O. Jumilla. Los resultados han mostrado que los parámetros de la barrica afectan más a los aromas del vino y su caracterización sensorial que a los parámetros cromáticos y nutricionales. Los vinos de Monastrell envejecidos en barricas de menores volúmenes y mayor nivel de tostado presentan una mayor concentración de compuestos aromáticos, aunque son menos preferidos sensorialmente.
Para la crianza de los vinos de Cabernet Sauvignon, la preferencia sensorial se ha correspondido con vinos envejecidos en barricas de volúmenes pequeños, de roble americano y tostado M+, donde aparecen mayores concentraciones de compuestos aromáticos, no aportando la tonelería diferencias muy grandes. Resultados similares se han encontrado en los vinos de Petit Verdot / The effect of barrel volume, toast level, oak wood origin and cooperage on chromatic, aromatic, sensory and healthy properties of Monastrell, Cabernet Sauvignon and Petit Verdot wines has been studied. The results have shown that Monastrell wines aged in the smallest barrels and with the highest toast level showed the highest aromatic compound concentrations although they were sensorially less preferred.
The use of small American oak barrels, with M+ toast level for Cabernet Sauvignon ageing showed wines with the higher volatile compound concentrations and the better sensory properties. Similar results were observed in Petit Verdot wines. Chromatic properties and antioxidant capacity of the wines did hardly show any correlation with the different factors studied.
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Caracterização analítica e sensorial de vinhos Cabernet Sauvignon de diferentes altitudes de Santa CatarinaFalcão, Leila Denise January 2007 (has links)
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Agrárias. Programa de Pós-Graduação em Ciência dos Alimentos. / Made available in DSpace on 2012-10-23T11:52:24Z (GMT). No. of bitstreams: 1
246722.pdf: 2298748 bytes, checksum: 89dc51cefe3264f5a778a85dea823757 (MD5) / Antocianinas são corantes naturais que proporcionam cores atrativas e brilhantes à maioria das plantas, colorindo-as do vermelho vivo ao violeta. Estes pigmentos possuem propriedades benéficas reconhecidas, porém ainda são pouco utilizados na indústria de alimentícia devido à sua instabilidade frente às etapas de processamento de alimentos. A reação de copigmentação das antocianinas com compostos incolores (copigmentos) naturalmente presentes nas plantas é estudada in vitro, em sistemas modelos, buscando viabilizar as antocianinas como corantes naturais. Flavonóides não antociânicos, aminoácidos, nucleosídios, ácidos orgânicos e as próprias antocianinas podem agir como copigmentos. No presente estudo, avaliou-se o efeito da adição dos ácidos orgânicos tânico e gálico ao extrato bruto de antocianinas de uvas Cabernet Sauvignon, em solução tampão e solução modelo de bebida isotônica estocadas sob diferentes condições de armazenamento. Calculou-se o tempo de meia vida e a percentagem de retenção de cor de todas as amostras estudadas. O efeito da adição de ácido tânico às antocianinas de uva (Cabernet Sauvignon) e à betalaínas extraídas de beterrada (Asgrow Wonder) foi avaliado em iogurte. A reação de copigmentação entre os ácidos orgânicos e os pigmentos avaliados em solução tampão, foi confirmada por espectrofotometria de absorção UV-Visível. Contudo, a complexação das antocianinas foi significativamente afetada pelo pH (3,0 e 4,0), temperatura (4±1ºC e 29±2ºC), atmosfera (presença e ausência de nitrogênio) e o ambiente (luz e escuro) em que as amostras foram armazenadas. A estabilidade das antocianinas com e sem adição de ácido tânico foi similar em solução tampão e solução modelo de bebida isotônica, sendo que o ácido tânico (1:1, p/v) aumentou o tempo de meia vida das amostras. Porém em iogurte não foi observado efeito protetor do ácido tânico às antocianinas ao nível de 5% de significância, enquanto que para betalaínas em iogurte, a adição de ácido tânico aumentou o tempo de meia vida e a percentagem de retenção de cor das amostras. A adição de ácido gálico (2:1, p/v) não influenciou na estabilidade das antocianinas de uva em solução tampão e em solução modelo de bebida isotônica.
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Caracterização dos vinhos Merlot e Cabernet Sauvignon da serra gaúcha através de determinação das razões isotópicas 13C/12C e 18O/16OAdami, Laurien 19 December 2006 (has links)
Neste trabalho foram estudados vinhos provenientes de microvinificações das variedades Merlot e Cabernet Sauvignon das sub-regiões de Pinto Bandeira, Vale dos Vinhedos, Nova Pádua e Monte Belo do Sul, nas safras de 2005 e 2006. Foram determinadas as razões isotópicas 13C/12C do etanol e 18O/16O da água e do etanol, buscando possível diferenciação entre as variedades e safras de produção, e provável relação entre o local de origem e suas características geográficas (altitude e latitude) e climatológicas (temperatura, precipitação pluviométrica e umidade). Utilizou-se um espectrômetro de massas de razão isotópica (IRMS) acoplado a um analisador elementar, para análise de 13C/12C do etanol e 18O/16O da água e a um cromatógrafo gasoso, para análise de 18O/16O do etanol. Em relação aos valores de δ13C, observou-se que a diferenciação entre as sub-regiões amostrais são menos seletivas e não seguem mesma ordem estatística encontrada para as análises δ18O, porém a análise de δ13C do etanol pode servir para diferenciar sub-regiões que não são diferenciadas estatisticamente pelas análises de δ18O. O comportamento dos valores de δ18O da água e do etanol obedecem mesma ordem estatística de diferenciação. Independente da variedade de uva utilizada neste trabalho, foi possível diferenciar as sub-regiões através da análise isotópica de δ18O, nas duas safras de produção, com exceção do Vale dos Vinhedos e Monte Belo do Sul, safra 2005, que não apresentaram diferenças estatísticas. As latitudes das diferentes sub-regiões apresentaram diferença estatística e demonstraram influência principalmente nos valores de δ18O da água. As análises de δ18O da água e do etanol do vinho mostraram-se mais seletivas e eficientes na discriminação das sub-regiões de cultivo do que as análises de δ13C do etanol. Foi observada uma forte correlação entre os valores de δ18O da água e do etanol. A altitude e a latitude influenciam principalmente os valores de δ18O da água e do etanol. As influências climáticas são mais marcantes na distinção entre safras de produção do que sub-regiões de cultivo. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-14T18:11:59Z
No. of bitstreams: 1
Dissertacao Laurien Adami.pdf: 946622 bytes, checksum: 1405d2dd9ccbcd048e59ac45e36fd0f7 (MD5) / Made available in DSpace on 2014-05-14T18:11:59Z (GMT). No. of bitstreams: 1
Dissertacao Laurien Adami.pdf: 946622 bytes, checksum: 1405d2dd9ccbcd048e59ac45e36fd0f7 (MD5) / In this work, wines provided by micro-winemakings of the variety Merlot and Cabernet Sauvignon of the sub-regions of Pinto Bandeira, Vale dos Vinhedos, Nova Pádua and Monte Belo do Sul in the 2005 and 2006 harvest have been studied. It has been established the isotopic ratios 13C/12C of the ethanol and 18O/16O of the water and ethanol, seeking for a possible differentiation among the varieties and production harvests, and a possible relation between the place of origin and its geographic features (altitude and latitude) and climatological conditions (temperature, precipitation and humidity). It has been used a isotope ratio mass spectrometer (IRMS) coupled to an elementar analyzer for the analysis of the 13C/12C of the ethanol and 18O/16O of the water and to a gas chromatograph for the analysis of 18O/16O of the ethanol. In relation to the values of δ13C, it is observed that the differentiation among the sampling sub-regions are less selective and do not follow the same statistical order found for the analysis of δ18O, however, the analysis of δ13C of the ethanol may be used to differentiate sub-regions that are not differentiated statistically by the analysis of δ18O. The value behaviors of δ18O of the water and the ethanol follow the same statistical order of differentiation. Regardless of the grape variety used in this work, it has been possible to differentiate the sub-regions through the isotopic analysis of the δ18O, in both production harvests, except for the Vale dos Vinhedos and Monte Belo do Sul, 2005 harvest, which did not present statistical differences. The latitudes of the different sub-regions presented statistical differences and demonstrated an influence mainly in the values of δ18O of the water. The analysis of δ18O of the water and the ethanol of the wine conveyed to be more selective and efficient in the discrimination of the cultivation sub-regions than the analysis of δ13C of the ethanol. It has been observed a strong correlation between the values of δ18O of the water and the ethanol. The altitude and latitude influence mainly the values of δ18O of the water and the ethanol. The climate influences are more noteworthy in distinguishing the production harvests than the cultivation sub-regions.
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Caracterização dos vinhos Merlot e Cabernet Sauvignon da serra gaúcha através de determinação das razões isotópicas 13C/12C e 18O/16OAdami, Laurien 19 December 2006 (has links)
Neste trabalho foram estudados vinhos provenientes de microvinificações das variedades Merlot e Cabernet Sauvignon das sub-regiões de Pinto Bandeira, Vale dos Vinhedos, Nova Pádua e Monte Belo do Sul, nas safras de 2005 e 2006. Foram determinadas as razões isotópicas 13C/12C do etanol e 18O/16O da água e do etanol, buscando possível diferenciação entre as variedades e safras de produção, e provável relação entre o local de origem e suas características geográficas (altitude e latitude) e climatológicas (temperatura, precipitação pluviométrica e umidade). Utilizou-se um espectrômetro de massas de razão isotópica (IRMS) acoplado a um analisador elementar, para análise de 13C/12C do etanol e 18O/16O da água e a um cromatógrafo gasoso, para análise de 18O/16O do etanol. Em relação aos valores de δ13C, observou-se que a diferenciação entre as sub-regiões amostrais são menos seletivas e não seguem mesma ordem estatística encontrada para as análises δ18O, porém a análise de δ13C do etanol pode servir para diferenciar sub-regiões que não são diferenciadas estatisticamente pelas análises de δ18O. O comportamento dos valores de δ18O da água e do etanol obedecem mesma ordem estatística de diferenciação. Independente da variedade de uva utilizada neste trabalho, foi possível diferenciar as sub-regiões através da análise isotópica de δ18O, nas duas safras de produção, com exceção do Vale dos Vinhedos e Monte Belo do Sul, safra 2005, que não apresentaram diferenças estatísticas. As latitudes das diferentes sub-regiões apresentaram diferença estatística e demonstraram influência principalmente nos valores de δ18O da água. As análises de δ18O da água e do etanol do vinho mostraram-se mais seletivas e eficientes na discriminação das sub-regiões de cultivo do que as análises de δ13C do etanol. Foi observada uma forte correlação entre os valores de δ18O da água e do etanol. A altitude e a latitude influenciam principalmente os valores de δ18O da água e do etanol. As influências climáticas são mais marcantes na distinção entre safras de produção do que sub-regiões de cultivo. / In this work, wines provided by micro-winemakings of the variety Merlot and Cabernet Sauvignon of the sub-regions of Pinto Bandeira, Vale dos Vinhedos, Nova Pádua and Monte Belo do Sul in the 2005 and 2006 harvest have been studied. It has been established the isotopic ratios 13C/12C of the ethanol and 18O/16O of the water and ethanol, seeking for a possible differentiation among the varieties and production harvests, and a possible relation between the place of origin and its geographic features (altitude and latitude) and climatological conditions (temperature, precipitation and humidity). It has been used a isotope ratio mass spectrometer (IRMS) coupled to an elementar analyzer for the analysis of the 13C/12C of the ethanol and 18O/16O of the water and to a gas chromatograph for the analysis of 18O/16O of the ethanol. In relation to the values of δ13C, it is observed that the differentiation among the sampling sub-regions are less selective and do not follow the same statistical order found for the analysis of δ18O, however, the analysis of δ13C of the ethanol may be used to differentiate sub-regions that are not differentiated statistically by the analysis of δ18O. The value behaviors of δ18O of the water and the ethanol follow the same statistical order of differentiation. Regardless of the grape variety used in this work, it has been possible to differentiate the sub-regions through the isotopic analysis of the δ18O, in both production harvests, except for the Vale dos Vinhedos and Monte Belo do Sul, 2005 harvest, which did not present statistical differences. The latitudes of the different sub-regions presented statistical differences and demonstrated an influence mainly in the values of δ18O of the water. The analysis of δ18O of the water and the ethanol of the wine conveyed to be more selective and efficient in the discrimination of the cultivation sub-regions than the analysis of δ13C of the ethanol. It has been observed a strong correlation between the values of δ18O of the water and the ethanol. The altitude and latitude influence mainly the values of δ18O of the water and the ethanol. The climate influences are more noteworthy in distinguishing the production harvests than the cultivation sub-regions.
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