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Sensory and chemical evaluation of riesling, chardonnay and pinot noir fermented by different strains of Saccharomyces cerevisiaeDumont, Ann 23 November 1994 (has links)
Fermentation of the grape must into wine is one of the most important steps
in winemaking. Selected yeast strains of Saccharomyces cerevisiae have
been used for many years to ensure complete and even fermentations. The
formation of volatile compounds also occurs during fermentation and will
influence the sensory perception of the wine. The main objective of the
research was to study the sensory and chemical composition of 1992 Oregon
Riesling, Chardonnay and Pinot Noir wines fermented with different
commercial S.cerevisiae strains.
In the first study, Free-Choice Profiling was used to study the sensory
profiles of all three varieties after 7 and 20 months of aging. This method was
used in order to utilize a panel of expert winemakers for the tastings. The
sensory data analyzed through Generalized Procrustes Analysis showed that
some strains were similar while others were different in terms of aroma and
flavor at 7 months of age. After 20 months of aging, differences and
similarities were still present although the sensory profiles were different from the young wines. This last finding showed that differences are still present
after a period of aging.
In the second study, the chemical composition of all three varieties and the
volatile composition of selected wines of Riesling and Chardonnay were
studied. In both white varieties, statistical differences in titratable acidity,
residual sugar, volatile acidity and malate content resulted from fermentation
with different yeast strains. The volatile composition was qualitatively similar,
but some quantitative differences, as relative concentration, were found.
Whether or not those differences had a sensory impact was not investigated.
Results of the present study showed the need for further studies in order to
understand the role of yeast in flavor development. Relationships between
sensory profiles and volatile composition could help winemakers to
understand the influence of a selected strain on a particular variety and to
select yeast strains to optimize wine quality. / Graduation date: 1995
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Detection and identification of wine spoilage microbes using PCR-based DGGE analysisBester, Linka 03 1900 (has links)
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2009. / Grape juice is transformed into wine through the complex processes of alcoholic and
malolactic fermentation that is performed by yeasts, lactic acid bacteria and acetic acid
bacteria. However, the microbes involved in these processes do not only take part in
ensuring the successful production of wine, but also cause spoilage of the wine if their
growth is not controlled.
Conventional, culture-dependent methods of microbiology have been used as the
main technique in detecting and identifying these spoilage microbes. Cultureindependent
techniques of molecular biology have recently become more popular in
detecting possible spoilage microbes present in must and wine, since it allows the
detection and identification of viable, but non-culturable microbes and are not as timeconsuming
as conventional microbiological methods.
The aim of this study was to investigate the sustainability of polymerase chain
reaction (PCR)-based denaturing gradient gel electrophoresis (DGGE) analysis in
detecting wine spoilage microbes inoculated into sterile saline solution (SSS) (0.85%
(m/v) NaCl) and sterile white wine and red wine as single microbial species and as part
of mixed microbial populations. Three methods of DNA isolation from SSS, sterile white
wine and sterile red wine inoculated with reference microbial strains were compared in
terms of DNA concentration and purity, as well as simplicity of the technique. These
three DNA isolation methods were the TZ-method, the proteinase K-method and the
phenol extraction method. DNA could not successfully be isolated from red wine using
any of the three DNA isolation methods. The TZ-method was the method of choice for
the isolation of DNA from inoculated SSS and sterile white wine as this technique gave
the best results in terms of simplicity, DNA concentration and purity.
PCR and DGGE conditions were optimised for the universal primer pair,
HDA1-GC and HDA2, the wine-bacteria specific primer pair, WBAC1-GC and WBAC2,
and the yeast specific primer pair, NL1-GC and LS2. DNA from Acetobacter
pasteurianus, Lactobacillus plantarum, Pediococcus pentosaceus, Oenococcus oeni,
Brettanomyces bruxellensis and Saccharomyces cerevisiae were amplified with the
appropriate primers and successfully resolved with DGGE analysis. PCR and DGGE
detection limits were successfully determined when 106 cfu.ml-1 of the reference
microbes, A. pasteurianus, Lb. plantarum, Pd. pentosaceus and B. bruxellensis were
separately inoculated into SSS and sterile white wine. It was possible to detect low
concentrations (101 cfu.ml-1) with PCR for A. pasteurianus, Lb. plantarum, Grape juice is transformed into wine through the complex processes of alcoholic and
malolactic fermentation that is performed by yeasts, lactic acid bacteria and acetic acid
bacteria. However, the microbes involved in these processes do not only take part in
ensuring the successful production of wine, but also cause spoilage of the wine if their
growth is not controlled.
Conventional, culture-dependent methods of microbiology have been used as the
main technique in detecting and identifying these spoilage microbes. Cultureindependent
techniques of molecular biology have recently become more popular in
detecting possible spoilage microbes present in must and wine, since it allows the
detection and identification of viable, but non-culturable microbes and are not as timeconsuming
as conventional microbiological methods.
The aim of this study was to investigate the sustainability of polymerase chain
reaction (PCR)-based denaturing gradient gel electrophoresis (DGGE) analysis in
detecting wine spoilage microbes inoculated into sterile saline solution (SSS) (0.85%
(m/v) NaCl) and sterile white wine and red wine as single microbial species and as part
of mixed microbial populations. Three methods of DNA isolation from SSS, sterile white
wine and sterile red wine inoculated with reference microbial strains were compared in
terms of DNA concentration and purity, as well as simplicity of the technique. These
three DNA isolation methods were the TZ-method, the proteinase K-method and the
phenol extraction method. DNA could not successfully be isolated from red wine using
any of the three DNA isolation methods. The TZ-method was the method of choice for
the isolation of DNA from inoculated SSS and sterile white wine as this technique gave
the best results in terms of simplicity, DNA concentration and purity.
PCR and DGGE conditions were optimised for the universal primer pair,
HDA1-GC and HDA2, the wine-bacteria specific primer pair, WBAC1-GC and WBAC2,
and the yeast specific primer pair, NL1-GC and LS2. DNA from Acetobacter
pasteurianus, Lactobacillus plantarum, Pediococcus pentosaceus, Oenococcus oeni,
Brettanomyces bruxellensis and Saccharomyces cerevisiae were amplified with the
appropriate primers and successfully resolved with DGGE analysis. PCR and DGGE
detection limits were successfully determined when 106 cfu.ml-1 of the reference
microbes, A. pasteurianus, Lb. plantarum, Pd. pentosaceus and B. bruxellensis were
separately inoculated into SSS and sterile white wine. It was possible to detect low
concentrations (101 cfu.ml-1) with PCR for A. pasteurianus, Lb. plantarum,
iv
Pd. pentosaceus, and B. bruxellensis in SSS when amplified with the HDA1-GC and
HDA2 primer pair. A PCR detection limit of 102 cfu.ml-1 was determined in sterile white
wine for Pd. pentosaceus and 103 cfu.ml-1 for B. bruxellensis using this primer pair. The
results obtained from the PCR amplification with the WBAC1-GC and WBAC2 primer
pair compared well with the results of the HDA1-GC and HDA2 primer pair.
The results from the DGGE detection limits indicated that it was possible to
detect lower concentrations (101 – 102 cfu.ml-1) of A. pasteurianus, Lb. plantarum and
Pd. pentosaceus with the HDA1-GC and HDA2 primer pair than the WBAC-GC and
WBAC2 primer pair (102 – 104 cfu.ml-1). Lower detection limits were also determined for
B. bruxellensis amplified with the HDA1-GC and HDA2 primer pair (103 – 104 cfu.ml-1)
than with the NL1-GC and LS2 primer pair (105 cfu.ml-1).
PCR and DGGE detection limits for the inoculation of A. pasteurianus,
Lb. plantarum and B. bruxellensis at an inoculum of 108 cfu.ml-1 as part of mixed
populations in SSS and sterile white wine compared well with the results obtained from
the reference microbes inoculated as single microbial species. PCR detection limits of
101 cfu.ml-1 were determined for all three reference microbes inoculated as part of
mixed populations when amplified with the HDA1-GC and HDA2 and the WBAC1-GC
and WBAC2 primer pairs. It was observed that similar or higher DGGE detection limits
were obtained for the reference microbes inoculated in sterile white wine
(101 – 107 cfu.ml-1) than when inoculated into SSS (101 – 105 cfu.ml-1).
PCR-based DGGE analysis proved to be a technique that could be used
successfully with the universal, wine-bacteria and yeast specific primer pairs for the
detection of A. pasteurianus, Lb. plantarum, Pd. pentosaceus and B. bruxellensis. The
culture-independent technique makes the early detection of possible spoilage microbes
at low concentrations in wine possible.
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PCR-based DGGE identification of bacteria and yeasts present in South African grape must and wineSiebrits, Leoni 03 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Wine production involves complex interactions between a variety of yeasts and bacteria. Conventional microbiological methods can be used to identify the different microorganisms present in wine, but prove to be time-consuming and certain microbial species may not grow on synthetic isolation media. The aim of this study was to evaluate the microbial population present in two South African red wines, Pinotage and Merlot, as well as five spoilt commercial South African wines by using a non-culturable approach, polymerase chain reaction (PCR)-based denaturing gradient gel electrophoresis (DGGE). The results from the non-culturable approach were compared to conventional platings.
Unique PCR-based DGGE fingerprints were obtained for the Bacteria and yeasts present in the South African Pinotage and Merlot wines. Using yeast specific primers the Pinotage wine showed the presence of non-Saccharomyces yeasts at the beginning of the alcoholic fermentation, while Saccharomyces cerevisiae was present until the completion of the malo-lactic fermentation (MLF). This yeast was also identified during both the alcoholic fermentation and MLF of the Merlot wine using PCR-based DGGE and conventional plating. Using Bacteria specific primers, Lactobacillus plantarum and Lactobacillus sp. was identified in the Pinotage wine using PCR-based DGGE, while Lactobacillus brevis were isolated from Merlot wine using conventional platings.
Although the presence of S. cerevisiae is expected during wine fermentation, the presence of this microbe in bottled wine could lead to spoilage. Four of the spoilt commercial wine samples (RW1, RW2, RoW1 and WW1) were found to be spoilt by S. cerevisiae, while a fifth wine sample (RW3) was found to be spoilt by an Acetobacter sp. using PCR-based DGGE.
Members of the family Enterobacteriaceae were identified from all the wines using PCR-based DGGE, while Enterobacter sakazakii was identified from RW1 using PCR-based DGGE and conventional plating. The members of the family Enterobacteriaceae could possibly have contributed to the spoilage of the wine by producing undesirable secondary metabolites. PCR-based DGGE proved to be an alternative to conventional microbiological methods for the identification of the microbial species in South African red grape must and wine. This method also proved to be useful in the identification of spoilage microbes in spoilt commercial South African wines. / AFRIKAANSE OPSOMMING: Die produksie van rooi wyn behels komplekse interaksies tussen ‘n verskeidenheid van giste en bakterieë. Konvensionele mikrobiologiese metodes kan gebruik word om die verskillende mikro-organismes wat in rooi wyn teenwoordig is te identifiseer, maar dit blyk tydrowend te wees, terwyl sekere mikro-organismes nie groei op sintetiese media nie. Die doel van hierdie studie was om die mikrobiologiese populasie wat in twee Suid-Afrikaanse rooi wyne, Pinotage en Merlot, en vyf bederfde kommersiële wyne teenwoordig is, te evalueer met die gebruik van ‘n kultuur-onafhanklike benadering, polimerase ketting-reaksie (PKR)-gebaseerde denaturerende gradiënt jel elektroforese (DGJE). Die resultaat van die kultuur-onhafhanklike benadering was vergelyk met konvensionele uitplating tegnieke.
Unieke, ongeëwenaarde PKR-gebaseerde DGGE vingerafdrukke was verkry van die Bakterieë en giste aanwesig in die Pinotage en Merlot wyne. Deur gebruik te maak van gis-spesifieke inleiers het die Pinotage wyn die teenwoordigheid van nie-Saccharomyces giste getoon, terwyl Saccharomyces cerevisiae teenwoordig was tot en met die afhandeling van die appel-melksuur gisting (AMG). Hierdie gis is ook geïsoleer gedurende beide die alkoholiese gisting en AMG van die Merlot wyn deur gebruik te maak van PKR-gebaseerde DGGE en konvensionele uitplating tegnieke. Met Bakterieë-spesifieke inleiers, was Lactobacillus plantarum en Lactobacillus sp. geïdentifiseer in die Pinotage wyn deur gebruik te maak van PKR-gebaseerde DGGE, terwyl Lactobacillus brevis geïsoleer is uit Merlot wyn deur gebruik te maak van konvensionele uitplatings.
Alhoewel die teenwoordigheid van S. cerevisiae verwag word gedurende wynfermentasie, kan die teenwoordigheid van hierdie mikrobe in gebottelde wyn tot bederwing lei. Vier van die bedorwe kommersiële wynmonsters (RW1, RW2, RoW1 en WW1) was bederf deur S. cerevisiae, terwyl ‘n vyfde wynmonster (RW3) bederf was deur ‘n Acetobacter sp. deur die gebruik van PKR-gebaseerde DGGE.
Van al die wyne is lede van die Enterobacteriaceae familie geïdentifiseer deur gebruik gemaak te maak van PKR-gebaseerde DGGE, terwyl Enterobacter sakazakii geïsoleer is van RW1 met konvensionele uitplating. Die lede van die familie Enterobacteriaceae kon moontlik bygedra het tot die bederwing van die wyn deur ongewenste sekondêre metaboliete te produseer.
PKR-gebaseerde DGGE bewys ‘n alternatief tot die konvensionele mikrobiologiese metodes vir die identifikasie van die mikrobiese spesies in Suid-Afrikaanse rooi druif mos en wyn te wees. Hierdie metode het ook die bruikbaarheid in die identifikasie van mikrobes wat kommersiële Suid-Afrikaanse wyne bederf, bewys.
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The evaluation of malolactic fermentation starter cultures under South African winemaking conditionsVan der Merwe, Hanneli 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2007. / ENGLISH ABSTRACT: With ever increasing pressure on wine producers to lower the financial costs involved in
winemaking to be able to compete in the market, all while maintaining a high level of wine
quality, the focus on maintaining control over all aspects of the winemaking process are
greatly emphasized.
Malolactic fermentation (MLF) is one of the important processes in red wine production.
The advantages of this process, when performed successfully, is widely known and
accepted. One way to gain control over MLF is the use of MLF starter cultures. Starter
cultures usually consist of Oenococcus oeni that has been isolated from grapes or wines
and is in most cases available in a freeze-dried form ready for direct inoculation into the
wine when MLF is desired. Starter cultures are induced into wine and usually ensure the
immediate onset as well as a fast and clean execution of the process. Starter cultures
used in South Africa are in most cases isolated from cooler viticultural regions in the
Northern hemisphere. The constitution of wines from cooler viticultural regions, differ from
those in South Africa, which has a warm climate. The most important difference is the acid
content of the wines which is lower in South African must/wines and results into a higher
pH. The three most important changes that develop in wine during MLF are a decrease in
acidity due to the conversion of malic acid to the less harsh lactic acid, enhanced flavour
and aroma of wine and an increase in the microbiological stability of wine. The decrease
in acidity is very important for wines produced for grapes grown in cool viticulture regions.
In South Africa though, the climate is warm and higher pH’s are present in the musts and
wines and the de-acidification due to MLF is not the main aim but rather the
microbiological stabilisation. One of the compounds that could be produced by lactic acid
bacteria (LAB) is biogenic amines (BA’s). These compounds can be hazardous to human
health. This thesis focussed on the performance of MLF starter cultures in high pH South
African red wines.
The first objective of the study was to stretch MLF starter cultures in high pH red wines
of South Africa. Stretching means to use less than the prescribed dosage or the re-use of
starter cultures. The difference in MLF rate, the influence of the natural occurring LAB and
the levels of biogenic amines formed during MLF were determined for the different
stretching treatments. The results showed that different rates in malic acid degradation
were experienced between the treatments, but in all cases MLF fermentation was completed. Biogenic amines were formed at various levels and the influence of the natural
occurring LAB also played a role.
The second objective of the study was the evaluation of the effect of a wine isolated
LAB (Lactobacillus) and an acetic acid bacteria (AAB), inoculated with a MLF starter
culture had on MLF at different wine pH’s. It was found that especially in the case where
the Lactobacillus was inoculated in combination with the MLF starter culture a possible
stimulatory effect was experienced with regards to malic acid degradation rate. Biogenic
amine concentration was measured at the end of MLF and it was found that no histamine
and tyramine were formed in any of the treatments, while the putrescine and cadaverine
levels were found to be at approximately similar levels for the different treatments.
The third objective was to evaluate the possible influence of commercial tannin
additions and a pectolytic enzyme on rate of MLF and phenolic composition of high pH red
wine. The commercial tannins had possible inhibitory as well as stimulatory effects on the
rate of malic acid degradation especially during the initial stages of MLF, with the highest
dosage having the significant effect. The BA results showed difference in the levels
produced due to tannin additions as well as strain differences could exist. The phenolic
content showed a decrease in colour density, total red pigments, total phenolics and
anthocyanins between AF and MLF.
The fourth objective was to evaluate inoculation time of MLF starter cultures. The
results showed that the fastest AF/MLF time was with simultaneous inoculation of the
yeast and MLF starter cultures. It was also for this treatment where no histamine or
tyramine was detected at the end of MLF compared to the other inoculation strategies
(before the end of AF and after AF).
This study generated a large amount of novel data which made a valuable contribution
with regards to MLF in high pH red wines of South Africa. / AFRIKAANSE OPSOMMING: Die druk om wyne van hoë gehalte teen lae insetkoste te lewer om deel te bly van ’n
kompeterende mark, plaas die fokus weer sterk op onder andere die beheer van alle
aspekte van die wynmaak proses.
Appelmelksuurgisting (AMG) is een van die belangrikste prosesse van rooiwyn produksie.
Die voordele van AMG, in die geval van die suksesvolle implementering daarvan is
vandag bekend en word geredelik aanvaar. Een van die metodes om beheer te verkry oor
the proses van AMG is deur die gebruik van AMG aanvangskulture. AMG
aanvangskulture bestaan uit Oenococcus oeni wat geïsoleer word vanaf druiwe of
mos/wyn en is in meeste gevalle beskikbaar in ’n gevries-droogte vorm wat direk in wyn
geïnokuleer kan word. Aanvangskulture word in wyn geïnduseer om die onverpose
aanvang van AMG te bewerkstellig asook om ’n vinnige en skoon deurvoering van die
proses te verseker. Die aanvangskulture wat in Suid-Afrika vir hierdie doeleinde gebruik
word is in meeste van die gevalle verkry uit koue wingerdbou gebiede in die Noordelike
Halfrond. Die samestelling van druiwe van koue wingerdbou gebiede en dié van
Suid-Afrikaanse warm wingerdbou gebiede verskil. Die belangrikste verskil word ervaar in
die suur inhoud, wat laer is in Suid-Afrikaanse druiwe en dus lei tot ‘n hoër pH inhoud. Die
drie mees belangrikste veranderinge wat gedurende AMG in wyn plaasvind is die
vermindering van die suur, as gevolg van die omskakeling van appelsuur na melksuur, die
verbetering van die aroma en geur van wyn en die verbeterde mikrobiologiese stabiliteit.
Die afname in suur is veral belangrik in wyne van koue wingerbou gebiede omdat die
suur-inhoud daarvan soveel hoër is. In Suid-Afrika kan hierdie verlaging in suur egter lei
tot ’n verdere verhoging in die pH wat plat wyne en uiteindelik ’n verlaging in die kwaliteit
van wyn tot gevolg kan hê. Biogene amiene (BA) is verbinding wat melksuurbakterieë
(MSB) kan vorm gedurende AMG en kan ernstige implikasies hê vir die mens se
gesondheid.
Hierdie tesis fokus op die evaluering van AMG aanvangskulture in hoë pH rooi wyne
van Suid-Afrika.
Die eerste doelwit gedurende hierdie studie was om AMG kulture te rek en die invloed
daarvan in hoë pH rooiwyn te evalueer ten opsigte van the tempo van AMG, die rol van die
natuurlike MSB te bestudeer asook om die vlak van biogene amiene te bepaal vir die
verskillende behandelings. Die resultate het aan die lig gebring dat die rek van kulture verskille in die tempo van appelsuur afbraak tot gevolg het, maar dat AMG in alle gevalle
wel suksesvol deurgevoer kon word. Die BA’e wat gevorm is, was teenwoordig in
verskillende hoeveelhede.
Die tweede doelwit was om die effekt van die gesamentlike inokulasie van ’n wyn
geisoleerde MSB (Lactobacillus) asook ’n asynsuurbakterie (ASB) met ’n kommersiële
AMG aanvangskultuur op AMG te evalueer. Hierdie eksperiment is uitgevoer by
verskillende pH’s. Daar is gevind dat veral in die kombinasie inokulasie met die
Lactobacillus, die tempo van appelsuur afbraak moontlik gestimuleer was. Geen
histamien of tiramien is tydens AMG gevorm in hierdie eksperiment gevorm nie, terwyl
putresien en kadaverien teenwoordig was teen ongeveer gelyke vlakke vir die
behandelings.
Die derde doelwit was om die moontlike invloed van kommersiële tannien toevoegings
en die toevoeging van ’n pektolitiese ensiem te evalueer ten opsigte van AMG tempo die
fenoliese samestelling van rooiwyn te bestudeer. Verskillende kommersiële tanniene het
’n moontlike sowel as inhiberende uitwerking gehad, veral gedurende die aanvanklike
stadium AMG. Die grootste verskille is waargeneem in die behandelings waar die hoogste
dosisse tannien bygevoeg is. Die BA resultate toon dat verkillende vlakke geproduseer
was en dat hierdie verskille onstaan het as gevolg van verskille in tannien dosisse sowel
as aanvangskulture. Die fenoliese inhoud het ’n afname in kleur intensiteit, totale rooi
pigmente, totale fenole en antosianiene getoon vir die periode vanaf AF tot die einde van
AMG.
Die vierde doelwit was om the tyd van inokulasie van AMG aanvangskulture te
bestudeer. Die resultate het getoon dat die vinningste tydperk van AF/AMG was
ondervind in die geval waar die gis aanvangskulture gelyktydig met die AMG
aanvangskulture geïnokuleer was. Geen histamine en tyramine het ook in hierdie
behandeling ontwikkel nie, terwyl daar wel vlakke teenwoordig was in die ander
behandelings (inokulasie net voor die einde van AF en na afloop van AF).
Tydens hierdie studie is ’n groot hoeveelheid nuwe data geskep wat ‘n groot bydrae
ten opsigte van AMG in hoë pH rooi wyne vanaf Suid-Afrika kan lewer.
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Monitoring the quality control chain from vineyard to wine : an industrial case studySwanepoel, Marinda 03 1900 (has links)
Thesis (MSc (Wine Biotechnology))--University of Stellenbosch, 2006. / The production of premium quality wine is dependant on excellent management of the total wine production value chain. To achieve this we need rapid and reliable analytical tools. Over the last decade Fourier transform infrared (FT-IR) spectroscopy has made a significant contribution to wine research and in the last five years South African institutions have also exploited the use of this technology not only for research, but also in industrial cellars.
The FT-IR apparatus is equipped with global calibrations and therefore we first investigated the validity of these for South African conditions. To achieve this new calibration sets for pH, titratable acidity and °Brix were made and compared to the global calibrations with statistical methods. Results obtained between the °Brix calibrations displayed high correlation and the global calibration can therefore be implemented. However, the new TA calibration was more accurate than the global calibration. Results were inconclusive for the new pH calibration sample set and therefore needs to be enlarged before it can be validated as the possibility of being more accurate exists. It was concluded that FT-IR spectroscopy in the simultaneous measurement for °Brix, pH and TA in grape must showed potential for accurate analysis and quality control purposes in an industrial cellar. Rapid analysis of these parameters will lead to higher throughput of grape must samples in the laboratory as well as adhering to good laboratory practices by validation.
The importance of correct sample preparation in the laboratory was illustrated when using FT-IR spectroscopy for one-step analysis and adjustments to global calibrations. Results obtained showed that grape parameters such as °Brix, nitrogen content were not influenced by the two sample preparation methods (hand pressed vs. homogenised), but pH, TA, colour index, anthocyanins and polyphenols were influenced.
Important key factors were identified in the quality control chain from vineyard to the cellar. Numerous grape loads had an increase in microbial populations after harvesting the vineyard and transport to the weighbridge. Transport is critical especially for the vineyards in the Lutzville area (had the highest yeast population), which are situated the furthest from the cellar. Sauvignon blanc had the highest acetic acid bacteria and lactic acid bacteria populations compared to the other cultivars. Gluconic acid, glycerol and arabitol was highly correlated to each other. High populations of acetic acid bacteria and lactic acid bacteria also had high levels of gluconic acid and 2,3-butanediol in the grape juice. Meso-inositol differed significantly between the vineyard and weighbridge and it had a high standard deviation compared to the mean value of all the samples between the vineyard and weighbridge. Temperature of grape loads delivered to the cellar ranged from 14 to 36ºC, which had a major impact on the grape quality and the resultant wine.
It can be concluded for this study that management of the total value chain is of critical importance to ensure that A-grade grapes results in good quality wine that merits the effort of the grape producer.
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Investigation of resveratrol production by genetically engineered Saccharomyces cerevisiae strainsTrollope, Kim 12 1900 (has links)
Thesis (MSc (Wine Biotechnology))--University of Stellenbosch, 2006. / Resveratrol is a phytoalexin that is produced in the leaves and skins of grape berries in response to biotic and abiotic factors. Substitution and polymerisation of resveratrol units produce an array of compounds which form part of the active disease defence mechanism in grapevine.
Wine is one of the major sources of resveratrol in the human diet. Resveratrol is one of the phenolic compounds present in wine that mediates protective effects on human health. It has been shown to prevent the development of cardiovascular disease, cancer and pathogenesis related to inflammation.
Red wines contain higher levels of resveratrol than white wines owing to extended maceration times during fermentation on the skins. During white wine vinification skin contact is limited as skins are removed prior to fermentation. Thus, the extraction of resveratrol into white wines is minimal. The principal focus of our research is the development of a wine yeast strain capable of resveratrol production during grape must fermentation. It is proposed that red and white wines produced with such a resveratrol-producing yeast will contain elevated levels of resveratrol, and that added health benefits may be derived from their consumption.
Initial work done in our laboratory established that expressing multiple copies of the genes encoding coenzyme A ligase (4CL216) and resveratrol synthase (vst1) in laboratory yeast enabled the yeast to produce resveratrol, conditional to the supplementation of the growth medium with p-coumaric acid. This study focused on the optimisation of resveratrol production in Saccharomyces cerevisiae. It involved the integration and constitutive expression of 4CL216 from hybrid poplar and vst1 from grapevine. Integration and expression of these genes in three laboratory strains was confirmed by Southern and Northern blot analyses.
The evaluation of resveratrol production by yeast required the initial optimisation of the analytical techniques. We optimised the method for sample preparation from the intracellular fraction of yeast and devised a procedure for the assay of the extracellular fractions. The LCMSMS method was further developed to encompass detection and quantification of other compounds related to resveratrol production in yeast.
Comparison of resveratrol production in three different yeast genetic backgrounds indicated that the onset of production and the resveratrol yield is yeast strain dependent. Precursor feeding studies indicated that p-coumaric acid availability was a factor limiting maximal resveratrol production. Early indications were obtained that endogenously-produced resveratrol may have an impact on yeast viability during extended culture periods.
This study has broadened our understanding of the resveratrol production dynamics in S. cerevisiae and provided important indications as to where further optimisation would be beneficial in order to optimally engineer a wine yeast for maximal resveratrol production.
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Investigation of bacteriocins from lactic acid bacteria and their impact in winemakingKnoll, Caroline 12 1900 (has links)
Thesis (MSc (Wine Biotechnology))--University of Stellenbosch, 2007. / Bacteriocins are ribosomally synthesized antimicrobial peptides produced by bacteria and are active against other bacteria, either in the same species (narrow spectrum) or across genera (broad spectrum). The application of bacteriocins during the vinification process might help to prevent the production of undesired compounds by inhibiting the indigenous bacterial microflora and allowing malolactic fermentation to be conducted by a selected bacterial strain. Furthermore, the use of bacteriocins might allow reducing the total sulphur dioxide amount in wine.
The purpose of this study was the selection of lactic acid bacteria (LAB) belonging to the genera Oenococcus, Lactobacillus and Pediococcus with the ability to produce bacteriocins, with respective biological activity against undesired indigenous wine LAB and the capability to complete malolactic fermentation.
The first objective of this study was the screening of LAB isolated from South African red wines for the production of bacteriocins. Only 27 strains out of 330 wine isolates, belonging to the species Lb. plantarum, Lb. paracasei, Lb. hilgardii and O. oeni, showed activity towards various wine-related and non wine-related indicator strains with the colony-overlay method. It is the first time that bacteriocin activity is reported in O. oeni.
The second objective was the detection and identification of known structural bacteriocin genes of Lb. plantarum wine strains. Furthermore, the web server BAGEL was used to in silico analyse putative bacteriocin-encoding genes in the genome of O. oeni and primers were designed to amplify four possible bacteriocin-encoding genes. A PCR-based screening revealed the presence of the plantaricin encoding genes plnA, plnEF, plnJ and plnK in five selected Lb. plantarum strains. Moreover, PCR analysis rendered positive results with all four chosen putative bacteriocin-encoding genes in the eight tested O. oeni strains with antimicrobial activity. The latter genes of O. oeni were heterologously expressed in different Escherichia coli host strains, but no antimicrobial activity could be detected.
The third objective of this study was the transformation and expression of the heterologous bacteriocin genes nisin A and pediocin PA-1 in two selected Lb. plantarum strains. To enhance their antimicrobial activity a plasmid containing the nisin A gene was successfully cloned into the two strains. Indeed, an enhanced antimicrobial activity could be detected, but the transformed plasmid was not stable. The fourth objective in this project was the evaluation of bacteriocin production in liquid media. A co-culture experiment with a plantaricin producing Lb. plantarum strain and an Enterococcus faecalis strain as indicator was performed. A complete inhibition of cell growth of Ent. faecalis was observed within 72 hours.
The last objective was the evaluation of the impacts of phenolic compounds on the activity of nisin and pediocin. The short term influence of two phenolic acids, two flavan-3-ols, grape tannins and oak tannins on the activity of nisin and pediocin PA-1 was investigated. No influence on the activity was detected. Furthermore, synergistic effects on bacterial growth inhibition were observed.
This study confirms the potential use of either bacteriocin additives or bacteriocin-producing LAB in order to control the bacterial microflora during the vinification process.
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Sensory, chemical and consumer analysis of Brettanomyces spoilage in South African winesBotha, Janita J 03 1900 (has links)
Thesis (MSc Food Sc (Food Science))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: This study focussed on the sensory effects of the main volatile compounds produced by
Brettanomyces yeast causing spoilage in wine. This research firstly aimed to determine the
detection thresholds of eight Brett-related spoilage compounds in wine. The second aim was to
determine the sensory effect of the four most important Brett-related compounds when present
individually in wine. The third aim was to determine the sensory effects of these four compounds
when present in wine in a range of combinations, and to further investigate their effect on
consumer liking. Finally, this project aimed to investigate the incidence of these compounds in a
small range of South African wines.
The sensory detection thresholds of 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol, 4-
vinylphenol, 4-vinylguaiacol, isovaleric acid, isobutyric acid and acetic acid were determined.
Apart from 4-ethylcatechol, these values generally agreed well with recent literature where
values determined in wine are available. However, the discrepancies highlighted the importance
of the effect of the medium (wine) when determining sensory detection thresholds. The use of
the median as alternative calculation method was also investigated, and it was found that this
method gives more insightful results than the standard American Society of Testing Materials
(ASTM E679-04) method.
Four compounds, namely 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol and isovaleric acid
were profiled individually in wine using a trained sensory panel. It was found that all four
compounds caused a suppression of the natural berry-like character in the wine, which induced
a sick-sweet character. 4-ethylphenol contributed Elastoplast™ and leather aromas in the wine,
both of which are commonly associated with Brettanomyces taint. 4-ethylguaiacol added a
medicinal aroma to the wine, and 4-ethylcatechol and isovaleric acid were responsible for
savoury and pungent aromas, respectively.
4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol and isovaleric acid were also profiled in
combination according to the central composite design. Several univariate and multivariate
methods were applied to the dataset obtained. PARAFAC, a multiway method not widely
utilized regarding sensory data, was applied to the data, the results of which were
complementary to those obtained during univariate and multivariate analyses. It was found that
there is a great deal of interaction between the four compounds profiled in terms of sensory
effects. The most notable was the Elastoplast™ attribute, the intensity of which was affected by
all four compounds. The pungent attribute was also affected by the 4-ethylphenol concentration. Consumer analysis revealed that some of the samples spiked with Brettanomyces-spoilage
compounds were preferred to the unspiked (control sample). However, no further relationship
could be found between consumer liking and either chemical composition or sensory profile. It is
therefore speculated that consumer liking of Brettanomyces infected wine is driven by more
complex sensory or socio-demographic factors.
Finally, the concentration of 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol, 4-vinylphenol, 4-
vinylguaiacol, isovaleric acid, isobutyric acid and acetic acid was determined in a small set of
South African wines, selected to contain a high proportion of wines spoiled by Brettanomyces.
Significant correlations were found between 4-ethylphenol and 4-ethylguaiacol, as well as 4-
ethylphenol and isovaleric acid. However, no correlation could be found between 4-ethylphenol
and 4-ethylcatechol. It is speculated that this lack of relationship is due to the different precursor
profiles present in the analysed wines. This study paved the way for future investigations on the
sensory effects of Brettanomyces spoilage in Pinotage red wine. / AFRIKAANSE OPSOMMING: Hierdie studie het gefokus op die sensoriese invloed van die belangrikste vlugtige komponente
wat deur die Brettanomyces gis geproduseer word en bederf veroorsaak in wyn. Eerstens is
gefokus op die bepaling van die deteksiedrempelwaardes van agt Brett-verwante bederwende
komponente. Die tweede doelwit was om die sensoriese invloed van vier van die mees
belangrike Brett-komponente te bepaal wanneer hulle individueel in wyn voorkom. Die derde
doelwit was om die sensoriese invloed van hierdie vier komponente te bepaal wanneer hulle in
verskillende kombinasies in wyn voorkom, asook die effek daarvan op verbruikervoorkeur.
Laastens is gepoog om die voorkoms van hierdie komponente in ‘n klein seleksie van Suid-
Afrikaanse wyne te bepaal.
Die sensoriese deteksiedrempelwaardes vir 4-etielfenol, 4-etielguaiacol, 4-etielcatechol, 4-
vinielfenol, 4-vinielguaiacol, isovaleraatsuur, isobuteraatsuur en asynsuur is bepaal. Met die
uitsondering van 4-etielcatechol het die waardes oor die algemeen goed ooreengestem met
waardes wat onlangs in die wetenskaplike literatuur gepubliseer is. Die uitsonderings het egter
die belangrikheid van die medium (wyn) gedurende die bepaling van sensoriese
deteksiedrempelwaardes uitgelig. Die gebruik van die mediaan as ‘n alternatiewe
berekeningsmetode is ook ondersoek en daar is gevind dat hierdie metode meer insiggewende
resultate lewer as die standaard American Society of Testing Materials (ASTM E679-04)
metode.
Vier komponente naamlik 4-etielfenol, 4-etielguaiacol, 4-etielcatechol en isovaleraatsuur is
individueel in wyn geprofileer met behulp van ‘n opgeleide sensoriese paneel. Daar is gevind
dat al vier die komponente die natuurlike bessiekarakter in die wyn onderdruk terwyl dit
aanleiding gee tot ‘n onnatuurlike soet karakter. 4-etielfenol is gekenmerk aan Elastoplast™ en
leeragtige aromas in die wyn en beide van hulle word algemeen geassosieer met
Brettanomyces bederf. 4-etielguaiacol het ‘n medisinale aroma tot die wyn toegevoeg en 4-
etielcatechol en isovaleraatsuur het respektiewelik souterige (“savoury”) en sterk (“pungent”)
aromas tot gevolg gehad.
4-etielfenol, 4-etielguaiacol, 4-etielcatechol en isovaleraatsuur is ook in verskeie kombinasies
geprofileer volgens die sentrale saamgestelde ontwerp (“central composite design”). Verskeie
enkelveranderlike en meerveranderlike statistiese analisemetodes is ook op die datastel
uitgevoer. PARAFAC, ‘n meerrigtingsmetode wat nie normaalweg vir sensoriese analise data
gebruik word nie, is ook uitgevoer op die data en die resultate was komplimentêr tot die van die
enkelveranderlike en meerveranderlike analisemetodes. Daar is gevind dat, met betrekking tot sensoriese effekte, daar noemenswaardige interaksie tussen die vier komponente plaasvind.
Die mees opmerklike hiervan was die Elastoplast™ aroma, waarvan die intensiteit deur al vier
die ander komponente geaffekteer is. Verder is die sterk (“pungent”) aroma beïnvloed deur die
4-etielfenol konsentrasie.
Verbruikersvoorkeur-analise het aangedui dat sommige van die monsters waarby
Brettanomyces bederwende komponente gevoeg is, verkies word bó die kontrole-wyn. Daar
kon egter geen verdere verband gevind word tussen die verbruiker se voorkeur en, nog die
chemise komposisie of sensoriese profiele, van die wyn nie. Daar kan dus gespekuleer word
dat verbruiker voorkeur van Brettanomyces bederfde wyn gedryf word deur meer komplekse en
sosio-demografiese faktore.
Laastens is die konsentrasies van 4-etielfenol, 4-etielguaiacol, 4-etielcatechol, 4-vinielfenol, 4-
vinielguaiacol, isovaleraatsuur, isobuteraatsuur en asynsuur in ‘n seleksie van Suid-Afrikaanse
wyne bepaal. Dié wyne is spesifiek so gekies sodat ‘n aansienlike aantal van hulle met
Brettanomyces bederf was. Betekenisvolle korrelasies is gevind tussen 4-etielfenol and 4-
etielguaiacol, sowel as 4-etielfenol en isovaleraatsuur. Daar is egter geen korrelasie tussen 4-
etielfenol and 4-etielcatechol gevind nie. Daar word vermoed dat hierdie gebrek aan korrelasie
te wyte is aan die voorloperkomponent profiele teenwoordig in die wyne. Hierdie studie het die
weg gebaan vir verdere ondersoeke na die sensoriese effekte van Brettanomyces bederf in
Pinotage rooi wyn.
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Diferenciação da origem geográfica de vinhos elaborados com uvas de três regiões vitícolas de Santa Catarina através de análises isotópicas e elementos mineraisReffatti, Leonardo 16 December 2016 (has links)
A origem e a tipicidade dos vinhos são temas importantes e de grande interesse para produtores, consumidores e comerciantes. Ambos estão ligados à obtenção de um reconhecimento deste produto perante o mercado consumidor. O Brasil apresenta dimensões continentais e uma ampla diversidade de regiões produtoras de uvas e vinhos, em cada uma encontra-se características peculiares. Santa Catarina é o quarto estado brasileiro em área plantada com videiras no Brasil, apesar disso, é o segundo maior estado produtor de vinhos, apresentando grande potencial para vitivinicultura. Neste estudo coletou-se amostras de uvas de três regiões produtoras de vinhos objetivando diferenciá-las através da utilização de análises da razão isotópica de Oxigênio (18O) da água e do Carbono (13C) do etanol, bem como do conteúdo minerais dos vinhos. Foram estudados vinhos varietais, elaborados através de microvinificações, das variedades de uva Cabernet Sauvignon e Merlot, safra 2013, provenientes das regiões de Santa Catarina: Carbonífera, Vale do Rio do Peixe e Planalto Serrano de São Joaquim. As análises isotópicas foram realizadas por espectrometria de massa da razão isotópica (IRMS) e a determinação dos elementos minerais por espectrometria de massa com plasma indutivamente acoplado (ICP-MS). Os valores da razão isotópica do oxigênio (18O) da água do vinho Cabernet Sauvignon foram eficientes para diferenciar os vinhos das três regiões, apresentando maiores valores médios para a região Vale do Rio do Peixe 3,31‰, seguidos por valores da região Carbonífera 1,48‰ e valores mais negativos -2,70‰ para a região Planalto Serrano de São Joaquim. O 18O em vinhos Merlot também diferenciou as duas regiões estudadas, de maneira similar aos resultados da variedade Cabernet Sauvignon, onde os valores maiores ocorreram na região Vale do Rio do Peixe 3,72‰ e o mais negativo na região Planalto Serrano de São Joaquim -2,76‰. Os resultados de 18O dependem principalmente de condições climáticas no período pré-colheita das uvas. Os resultados obtidos do 13C do etanol dos vinhos Cabernet Sauvignon não diferenciaram as três regiões de Santa Catarina, porém os valores encontrados do 13C do etanol dos vinhos Merlot foram mais negativos na região Planalto Serrano de São Joaquim -29,55‰ e menos negativos na região Vale do Rio do Peixe -28,67‰, sendo possível diferenciar estas duas regiões. Na região Vale do Rio do Peixe foi possível diferenciar vinhos Cabernet Sauvignon -29,80‰ de vinhos Merlot -28,67‰, esta mesma diferenciação ocorreu para a região Planalto Serrano de São Joaquim, onde vinhos Cabernet Sauvignon apresentaram valores de -30,47‰ e vinhos Merlot -29,55‰. Um amplo conjunto de elementos minerais como B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, Nb, Cd, Sb, Cs, Ba e Pb foram quantificados para diferenciação geográfica das regiões estudadas. Nenhum dos elementos minerais estudados individualmente neste trabalho possibilitou a diferenciação das três regiões estudadas para vinhos Cabernet Sauvignon. Contudo, analisando os resultados obtidos para Mg, Al, Ca, Mn, Se, Rb, Sr, Zr, Nb, Cs e Ba, em conjunto, diferenciaram pelos menos uma das regiões estudadas para vinhos varietais de Cabernet Sauvignon, do mesmo modo para vinhos Merlot. A partir dos resultados do 18O, B, Mg, Al, V, Mn, Co, Cu, Se, Rb, Sr, Cd e Sb, obteve-se equações com classificação de 100% para as três regiões estudadas. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2017-04-26T14:04:26Z
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Dissertacao Leonardo Reffatti.pdf: 1201198 bytes, checksum: 541b71591becc056b52f84e624af9bf8 (MD5) / Made available in DSpace on 2017-04-26T14:04:26Z (GMT). No. of bitstreams: 1
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Previous issue date: 2017-04-26 / Wine origin and typicity are important issues and big interest for producers, consumers and traders. Both are linked to the achievement of wine recognition by the consumer market. Brazil has continental dimensions and a wide winegrowing diversity regions, each one with unique characteristics. Santa Catarina occupies the fourth state place in Brazilian surface area with vineyards, on the other hand, it´s the second in wine production, showing a potential for this activity. In this study, samples of three regions in Santa Catarina were collected aiming differ them by geographic localization, using oxygen isotopic ratio analysis (18O) of water, carbon isotopic ratio (13C) of ethanol, and mineral 85Rb and 88Sr wine content. Varietal Carbernet Sauvignon and Merlot wines were elaborated by microvinifications, vintage 2013, from the regions: Carbonífera, Vale do Rio do Peixe and Planalto Serrano de São Joaquim. Isotopic analysis of oxygen and carbon were performed by mass spectrometry isotope ratio (IRMS), and mineral elements by inductively coupled plasma-mass spectrometry (ICPMS). Wine water average values of 18O in Cabernet Sauvignon wines were efficient to differ wines from the three regions, demonstrating higher average values for Vale do Rio do Peixe region (3,31‰), followed by Carbonífera region (1,48‰), and Planalto Serrano de São Joaquim region showed negative values (-2,70‰). Similarly to Cabernet Sauvignon, wine water average values of 18O in Merlot wines were effective in differentiating just two regions, the higher values were exhibited for Vale do Rio do Peixe (3,72‰), and lower values for Planalto Serrano de São Joaquim (-2,76‰). Oxygen isotopic ratio depends mainly of whether conditions during grape maturation and harvest. Wine ethanol average values for 13C in Cabernet Sauvignon wines were not able to differ the three regions of Santa Catarina, however average values found to Merlot wines were able, evincing more negative values in Planalto Serrano de São Joaquim (-29,55‰), and less negative to Vale do Rio do Peixe (-28,67‰). Further on the geographic differentiation, the 13C showed potential to differentiate varieties inside a region. In Vale do Rio do peixe region, wine ethanol average 13C for Cabernet Sauvignon wines (-29,80‰) showed difference to Merlot wines (-28,57‰), the same differentiation occurred to Planalto Serrano de São Joaquim region, where Cabernet Sauvignon wines demonstrated values of (-30,47‰) and Merlot wines (-29,55‰). A wide range of mineral elements such as B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, Nb, Cd, Sb, Cs, Ba and Pb were quantified to geographic differentiation between the studied regions. None of the mineral elements individually studied in this work allowed the differentiation of the three regions studied for Cabernet Sauvignon wines. However, the results for Mg, Al, Ca, Mn, Se, Rb, Sr, Zr, Nb, Cs and Ba differentiated at least one of the studied regions in Cabernet Sauvignon wines, it was also possible to differentiate the two regions studied in Merlot wines. A group of 18O, B, Mg, Al, V, Mn, Co, Cu, Se, Rb, Sr, Cd e Sb results classified the three regions by 100%.
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Diferenciação da origem geográfica de vinhos elaborados com uvas de três regiões vitícolas de Santa Catarina através de análises isotópicas e elementos mineraisReffatti, Leonardo 16 December 2016 (has links)
A origem e a tipicidade dos vinhos são temas importantes e de grande interesse para produtores, consumidores e comerciantes. Ambos estão ligados à obtenção de um reconhecimento deste produto perante o mercado consumidor. O Brasil apresenta dimensões continentais e uma ampla diversidade de regiões produtoras de uvas e vinhos, em cada uma encontra-se características peculiares. Santa Catarina é o quarto estado brasileiro em área plantada com videiras no Brasil, apesar disso, é o segundo maior estado produtor de vinhos, apresentando grande potencial para vitivinicultura. Neste estudo coletou-se amostras de uvas de três regiões produtoras de vinhos objetivando diferenciá-las através da utilização de análises da razão isotópica de Oxigênio (18O) da água e do Carbono (13C) do etanol, bem como do conteúdo minerais dos vinhos. Foram estudados vinhos varietais, elaborados através de microvinificações, das variedades de uva Cabernet Sauvignon e Merlot, safra 2013, provenientes das regiões de Santa Catarina: Carbonífera, Vale do Rio do Peixe e Planalto Serrano de São Joaquim. As análises isotópicas foram realizadas por espectrometria de massa da razão isotópica (IRMS) e a determinação dos elementos minerais por espectrometria de massa com plasma indutivamente acoplado (ICP-MS). Os valores da razão isotópica do oxigênio (18O) da água do vinho Cabernet Sauvignon foram eficientes para diferenciar os vinhos das três regiões, apresentando maiores valores médios para a região Vale do Rio do Peixe 3,31‰, seguidos por valores da região Carbonífera 1,48‰ e valores mais negativos -2,70‰ para a região Planalto Serrano de São Joaquim. O 18O em vinhos Merlot também diferenciou as duas regiões estudadas, de maneira similar aos resultados da variedade Cabernet Sauvignon, onde os valores maiores ocorreram na região Vale do Rio do Peixe 3,72‰ e o mais negativo na região Planalto Serrano de São Joaquim -2,76‰. Os resultados de 18O dependem principalmente de condições climáticas no período pré-colheita das uvas. Os resultados obtidos do 13C do etanol dos vinhos Cabernet Sauvignon não diferenciaram as três regiões de Santa Catarina, porém os valores encontrados do 13C do etanol dos vinhos Merlot foram mais negativos na região Planalto Serrano de São Joaquim -29,55‰ e menos negativos na região Vale do Rio do Peixe -28,67‰, sendo possível diferenciar estas duas regiões. Na região Vale do Rio do Peixe foi possível diferenciar vinhos Cabernet Sauvignon -29,80‰ de vinhos Merlot -28,67‰, esta mesma diferenciação ocorreu para a região Planalto Serrano de São Joaquim, onde vinhos Cabernet Sauvignon apresentaram valores de -30,47‰ e vinhos Merlot -29,55‰. Um amplo conjunto de elementos minerais como B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, Nb, Cd, Sb, Cs, Ba e Pb foram quantificados para diferenciação geográfica das regiões estudadas. Nenhum dos elementos minerais estudados individualmente neste trabalho possibilitou a diferenciação das três regiões estudadas para vinhos Cabernet Sauvignon. Contudo, analisando os resultados obtidos para Mg, Al, Ca, Mn, Se, Rb, Sr, Zr, Nb, Cs e Ba, em conjunto, diferenciaram pelos menos uma das regiões estudadas para vinhos varietais de Cabernet Sauvignon, do mesmo modo para vinhos Merlot. A partir dos resultados do 18O, B, Mg, Al, V, Mn, Co, Cu, Se, Rb, Sr, Cd e Sb, obteve-se equações com classificação de 100% para as três regiões estudadas. / Wine origin and typicity are important issues and big interest for producers, consumers and traders. Both are linked to the achievement of wine recognition by the consumer market. Brazil has continental dimensions and a wide winegrowing diversity regions, each one with unique characteristics. Santa Catarina occupies the fourth state place in Brazilian surface area with vineyards, on the other hand, it´s the second in wine production, showing a potential for this activity. In this study, samples of three regions in Santa Catarina were collected aiming differ them by geographic localization, using oxygen isotopic ratio analysis (18O) of water, carbon isotopic ratio (13C) of ethanol, and mineral 85Rb and 88Sr wine content. Varietal Carbernet Sauvignon and Merlot wines were elaborated by microvinifications, vintage 2013, from the regions: Carbonífera, Vale do Rio do Peixe and Planalto Serrano de São Joaquim. Isotopic analysis of oxygen and carbon were performed by mass spectrometry isotope ratio (IRMS), and mineral elements by inductively coupled plasma-mass spectrometry (ICPMS). Wine water average values of 18O in Cabernet Sauvignon wines were efficient to differ wines from the three regions, demonstrating higher average values for Vale do Rio do Peixe region (3,31‰), followed by Carbonífera region (1,48‰), and Planalto Serrano de São Joaquim region showed negative values (-2,70‰). Similarly to Cabernet Sauvignon, wine water average values of 18O in Merlot wines were effective in differentiating just two regions, the higher values were exhibited for Vale do Rio do Peixe (3,72‰), and lower values for Planalto Serrano de São Joaquim (-2,76‰). Oxygen isotopic ratio depends mainly of whether conditions during grape maturation and harvest. Wine ethanol average values for 13C in Cabernet Sauvignon wines were not able to differ the three regions of Santa Catarina, however average values found to Merlot wines were able, evincing more negative values in Planalto Serrano de São Joaquim (-29,55‰), and less negative to Vale do Rio do Peixe (-28,67‰). Further on the geographic differentiation, the 13C showed potential to differentiate varieties inside a region. In Vale do Rio do peixe region, wine ethanol average 13C for Cabernet Sauvignon wines (-29,80‰) showed difference to Merlot wines (-28,57‰), the same differentiation occurred to Planalto Serrano de São Joaquim region, where Cabernet Sauvignon wines demonstrated values of (-30,47‰) and Merlot wines (-29,55‰). A wide range of mineral elements such as B, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Zr, Nb, Cd, Sb, Cs, Ba and Pb were quantified to geographic differentiation between the studied regions. None of the mineral elements individually studied in this work allowed the differentiation of the three regions studied for Cabernet Sauvignon wines. However, the results for Mg, Al, Ca, Mn, Se, Rb, Sr, Zr, Nb, Cs and Ba differentiated at least one of the studied regions in Cabernet Sauvignon wines, it was also possible to differentiate the two regions studied in Merlot wines. A group of 18O, B, Mg, Al, V, Mn, Co, Cu, Se, Rb, Sr, Cd e Sb results classified the three regions by 100%.
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