Tannat Red Wines Research Articles

Chemical typicity of tropical tannat red wines from sub-middle São Francisco Valley, Brazil.

Chemical typicity of tropical tannat red wines from sub-middle São Francisco Valley, Brazil.

Desarrollo y evaluación de alternativas tecnológicas para reducir el contenido de alcohol y el pH de vinos tintos

The objective of this research was to develop and evaluate technologies that reduce the alcohol content and pH of Pinot noir and Tannat red wines without reduce their color and phenolic composition. To reduce wine alcohol content and pH, a partial substitution of the must of ripe grapes by must of unripe grapes was evaluated. Faced with a possible dilution effect when substituting must, a pre-fermentation hot maceration was additionally evaluated. Must substitution was an effective technique to reduce the alcohol content and the pH without modifying the phenolic concentration of wines made in both cultivars. Additionally, the pre-fermentation hot maceration increased the color of the wine and its concentration in total polyphenols, anthocyanins, catechins and proanthocyanins. The impact of both techniques was determined by the varietal characteristics and the ripening conditions, so it is necessary to continue adapting these techniques to different cultivars and in other growing situations. The development of these technologies is an interesting tool because they can be applied differentially according to the oenological potential of the grape in each harvest, mitigating the effects of climate change on its composition.

Ultrasound assisted extraction of bioactive compounds in fresh and freeze-dried Vitis vinifera cv Tannat grape pomace

Tannat red wine residues present a unique polyphenolic composition. Revalorization of this residue depends on adequate extraction technologies to assure process sustainability. Influence of temperature (15−60 °C), ultrasound (US) power (0−100 W) and US application time (5−50 min) on Ultrasound Assisted Extraction (UAE) of fresh and freeze-dried Tannat grape pomace was evaluated. UAE was performed in a US bath, following extraction kinetics throughout 50 min by assessing: total polyphenol content (TPC), total monomeric anthocyanins (TMAC) and total antioxidant capacity (AOC). Additionally, HPLC analysis was performed to determine extracted compounds’ profile. Results showed UAE enhanced extraction in both fresh and freeze-dried pomace. In fresh pomace, UAE yielded extracts 50% richer in TPC and TMAC on average when compared to conventional extractions, while in freeze-dried pomace 180% increase in extraction was achieved. In fresh and freeze-dried pomace, US application allowed extraction of different compounds with respect to conventional extraction. This work shows that UAE has potential for Tannat grape pomace valorization, yet UAE conditions should be carefully selected to favour desired extract composition.

Impact of Must Replacement and Hot Pre-Fermentative Maceration on the Color of Uruguayan Tannat Red Wines

This research aimed to evaluate the impact of different options for winemaking on the color composition of Uruguayan Tannat red wines. The techniques evaluated were the substitution of ripe grape juice with immature grape juice and the heating of the crushed grapes before fermentation, called must replacement and hot pre-fermentative maceration, respectively. These procedures were proposed to reduce the alcohol content and increase the phenolic composition of the wine, according to the expected effects of climate change and current trends in consumer preferences. The investigation was made over three consecutive years (2016, 2017, and 2018). Both winemaking techniques allow the enhancement of the chromatic characteristics of wines via the modification of the phenolic composition. Additionally, such techniques allow the overcoming of the well-known limitations in the extractability of anthocyanins presented by the Tannat cultivar. Hot pre-fermentative maceration increases the proportion of the most oxidizable molecules delphinidin-3-O-glucoside, cyanidin-3-O-glucoside, and petunidin-3-O-glucoside, suggesting heat inactivation of polyphenoloxidases enzymes. Must replacement and hot pre-fermentative maceration are technological alternatives that could significantly improve the intensity and chromatic characteristics of red wines.

Influence of the use of unripe grapes to reduce ethanol content and pH on the color, polyphenol and polysaccharide composition of conventional and hot macerated Pinot Noir and Tannat wines

The aim of this research was to determine the effectiveness of the substitution of grape juice of grapes with different maturation degree and prefermentative hot maceration to obtain Pinot Noir and Tannat red wines with lower alcohol content and pH and higher color and phenolic compound concentrations. Immature grape juice was extracted of grapes harvested in veraison and kept at 4 °C until its use. In technological maturity, the grapes harvested were destemmed, crushed and distributed in 12 containers per cultivar. Six were controls while in the other six 3 L of the original grape juice were substituted by 3 L of unripe grape juice. Next, three containers from each experimental group were traditionally macerated, while the other three were submitted to a prefermentative hot maceration (one hour at 60–70 °C). All treatments performed a fermentative maceration of 7 days. Wines produced from substituted musts had lower alcohol content (14% off) and pH (9% off) and higher titratable acidity (48% more), but no other important changes in wine components were detected. Prefermentative hot maceration increased wine color intensity (50%), total phenolic compounds (66%), total anthocyanin (42%), proanthocyanidin (65%) and polysaccharide (95%) concentrations. The joint consideration of both techniques is an interesting tool to simultaneously mitigate the problems caused by climate change with respect to the maturity of the grape and improve the color of the wine and its concentration in polysaccharides and phenolic compounds.

The Effect of Endozym β-split, a Commercial Enzyme Preparation Used for Aroma Release, on Tannat Wine Glycosides

Fil: Cid, Alicia Graciela. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Salta. Instituto de Investigaciones para la Industria Quimica. Universidad Nacional de Salta. Facultad de Ingenieria. Instituto de Investigaciones para la Industria Quimica; Argentina

Non-Saccharomyces and Saccharomyces strains co-fermentation increases acetaldehyde accumulation: effect on anthocyanin-derived pigments in Tannat red wines.

During fermentation, Saccharomyces cerevisiae releases into the medium secondary metabolic products, such as acetaldehyde, able to react with anthocyanins, producing more stable derived pigments. However, very limited reports are found about non-Saccharomyces effects on grape fermentation. In this study, six non-Saccharomyces yeast strains, belonging to the genera Metschnikowia and Hanseniaspora, were screened for their effect on red wine colour and wine-making capacity under pure culture conditions and mixed with Saccharomyces. An artificial red grape must was prepared, containing a phenolic extract of Tannat grapes that allows monitoring changes of key phenol parameters during fermentation, but without skin solids in the medium. When fermented in pure cultures, S. cerevisiae produced higher concentrations of acetaldehyde and vitisin B (acetaldehyde reaction-dependent) compared to M. pulcherrima M00/09G, Hanseniaspora guillermondii T06/09G, H. opuntiae T06/01G, H. vineae T02/05F and H. clermontiae (A10/82Fand C10/54F). However, co-fermentation of H. vineae and H. clermontiae with S. cerevisiae resulted in a significantly higher concentration of acetaldehyde compared with the pure S. cerevisiae control. HPLC-DAD-MS analysis confirmed an increased formation of vitisin B in co-fermentation treatments when compared to pure Saccharomyces fermentation, suggesting the key role of acetaldehyde. Copyright © 2016 John Wiley & Sons, Ltd.

Effects of Red Wine Tannat on Oxidative Stress Induced by Glucose and Fructose in Erythrocytes in Vitro.

The literature indicates that red wine presents in its composition several substances that are beneficial to health. This study has investigated the antioxidant effects of Tannat red wine on oxidative stress induced by glucose and fructose in erythrocytes in vitro, with the purpose to determine some of its majoritarian phenolic compounds and its antioxidant capacity. Erythrocytes were incubated using different concentrations of glucose and fructose in the presence or absence of wine. From these erythrocytes were determined the production of thiobarbituric acid reactive species (TBARS), glucose consumption, and osmotic fragility. Moreover, quantification of total phenolic, gallic acid, caffeic acid, epicatechin, resveratrol, and DPPH scavenging activity in wine were also assessed. Red wine showed high levels of polyphenols analyzed, as well as high antioxidant potential. Erythrocytes incubated with glucose and fructose had an increase in lipid peroxidation and this was prevented by the addition of wine. The wine increased glucose uptake into erythrocytes and was able to decrease the osmotic fragility of erythrocytes incubated with fructose. Altogether, these results suggest that wine leads to a reduction of the oxidative stress induced by high concentrations of glucose and fructose.

Effect of cold pre-fermentative maceration on the color and composition of young red wines cv. Tannat.

Cold Pre-fermentative Maceration (CPM) is an interesting winemaking technique to enhance the extraction of pigments, aroma and flavour compounds from grape skins to wine. This work aimed to evaluate the effect of Cold Pre-fermentative Maceration (CPM) on the composition of Tannat red wines produced in Uruguay in several vintages. For this purpose, wines elaborated by CPM were compared with control wines produced by Traditional Maceration (TM) in 4years. Control wines (TM) were made with classical fermentation on skins. The CPM was carried out with additions of dry ice for 5days to keep the must at 10 ºC. Wines were analysed at devatting. The impact of CPM on composition and color of wines was different in each year. Color intensity was significantly higher in CPM than control wines in 2007 and 2009 whereas the anthocyanins levels were higher in control wines every year. However, CPM wines had the highest polyphenols contents in 2007, 2009 and 2010 principally due to their catechins and proanthocyanidins contents. Anthocyanin profile was similar in the wines of each vintage, according to the varietal fingerprint. The highest contents of higher alcohols were verified in CPM wines. The Cold Pre-fermentative Maceration could have an important effect on the characteristics of Tannat red wines, although it depends strongly on the composition of the grapes of origin.

Low molecular-weight phenols in Tannat wines made by alternative winemaking procedures

Low molecular weight phenols of Tannat red wines produced by Traditional Maceration (TM), Prefermentative Cold Maceration (PCM), Maceration Enzyme (ENZ) and grape-Seed Tannins additions (ST), were performed and discussed. Alternatives to TM increased wine phenolic contents but unequally, ST increased mainly smaller flavans-3-ol, PCM anthocyanins and ENZ proanthocyanidins (up to 2250mg/L). However low molecular weight flavan-3-ols remained below 9mg/L in all wines, showing that there is not necessarily a correspondence between wine richness in total tannins and flavan-3-ols contents at low molecular weight. PCM wines had particularly high concentrations of tyrosol and tryptophol, yeast metabolism derived compounds. The use of grape-seed enological tannins did not increase grape seed derived phenolic compounds such as gallic acid. Caftaric acid was found in concentrations much higher than those reported in other grape varieties. Wine phenolic content and composition was considerably affected by the winemaking procedures tested.

Extracción de polifenoles y composición de vinos tintos Tannat elaborados por técnicas de maceración prefermentativa

Con el objetivo de evaluar el efecto de la técnica de maceración sobre la extracción de compuestos fenólicos y la composición del vino al descube, durante la vendimia 2011 se elaboraron vinos tintos Tannat por maceración prefermentativa en frío (MF: mosto sometido cinco días a una temperatura entre 5 y 10 °C con una maceración fermentativa posterior de ocho días), prefermentativa en caliente (MC: mosto sometido seis horas a temperatura entre 60-65 ºC previo a una maceración fermentativa de ocho) y tradicional (MT: mosto sometido a una maceración con fermentación de ocho días). Se comparó la extracción de polifenoles totales y de antocianos obtenida con cada técnica de vinificación, realizando análisis diarios de estos compuestos desde el encubado hasta el descube, en donde se determinó además la intensidad colorante, tonalidad y porcentajes de amarillo, rojo y azul para cada técnica empleada. La extracción de polifenoles totales y antocianos en los mostos MF presentó una cinética más lenta durante la maceración, produciendo vinos que no se diferenciaron significativamente de los elaborados por MT. Los mostos MC presentaron mayor extracción de polifenoles totales y antocianos durante la etapa prefermentativa, que se mantuvieron durante la fermentación alcohólica, obteniendo vinos con mayor intensidad colorante y mayor tonalidad respecto a los elaborados por MT. La maceración prefermentativa en caliente es una alternativa tecnológica que permite mejorar la extracción de polifenoles y potenciar el color de los vinos tintos Tannat,

Influence of grape composition and winemaking on the anthocyanin composition of red wines of Tannat

SummaryThe anthocyanin composition of Tannat red wines obtained with four winemaking techniques was evaluated in different years. The wines were elaborated with traditional maceration (TM), cold pre‐fermentative maceration, delayed extraction of anthocyanins and extended maceration. Two vinifications were carried out for each technique, employing 70 kg of grapes in each one. The anthocyanin composition of wines was analysed by high‐performance liquid chromatography–diode array detection. The results confirm the fundamental role of the grape composition on the anthocyanin composition of the wines. The winemaking had an important effect on the total concentration of anthocyanins and also may modify the anthocyanic profile of wines. The wines obtained with TM had higher or similar content of anthocyanins than those elaborated with the other techniques. Canonical discriminant analysis of data showed that vintage has a greater effect on anthocyanin concentration than winemaking techniques.

Pigment profile of red wines cv. Tannat made with alternative winemaking techniques

The pigment profile of Tannat red wines made with different winemaking techniques was evaluated over one year. The wines were made with one traditional and three alternative winemaking techniques: traditional maceration (TM), cold pre-fermentative maceration (CPM), delayed extraction of anthocyanins (DEA), and extended maceration (EM). Two vinifications were carried out for each technique, using 70 kg of grapes per technique. The wines were analyzed at devatting and 3, 6 and 12 months later. The pigment composition was analyzed by HPLC-DAD. The anthocyanin content of the control wines (TM) was significantly higher at all times. At devatting, the contents of 10 grape anthocyanins and some of their derived pigments showed statistical differences between the control wines and the other wines. The levels of vitisin A in the control wines showed no statistical differences with the levels in the CPM wines, but they were significantly higher than in the other wines. One year later, the TM wines showed significantly higher content only of delphinidin and petunidin 3-glucosides, delphinidin acetyl-glucoside and malvidin coumaryl-glucoside pyruvate. The TM and the CPM wines showed higher content in vitisin A and other anthocyanin-derived pigments. The concentrations of some derived pigments, like vitisin A, increased with time in all the wines, while the concentration of the grape anthocyanins decreased highly significantly. Discriminant analysis of the data showed a significant separation of the wines obtained at different ageing times, in spite of the important differences that resulted from the different winemaking techniques.

Searching a specific bottle for Tannat wine using a check-all-that apply question and conjoint analysis

An increasing share of fine wines is marketed through retail stores. In this context, packaging plays a major role in attracting consumers’ attention and influencing their purchase decisions. The aim of the present work was to identify a specific bottle for Tannat red wine, the typical Vitis vinifera grape of Uruguay, by studying the effect of bottle shape and colour on consumers’ sensory expectations and willingness to purchase. A consumer study was carried out with 64 fine wine consumers, who were first introduced a list of bottle colours and shapes and were asked to answer a check-all-that-apply question. Then, participants were asked to complete a conjoint analysis task about Tannat wine bottles. Results from the check-all-that-apply question showed that consumers associated the shape and colour of bottles with specific types and styles of wine. Conjoint analysis suggested that Bordeaux dark green or dark gray bottles might be the most appropriate for Tannat wine. Interestingly, results shown here may indicate the existence of risks if deep innovation is made in bottle shape designs, since consumers clearly preferred Bordeaux bottles for red wines.

The Effect of Bacterial Strain and Aging on the Secondary Volatile Metabolites Produced during Malolactic Fermentation of Tannat Red Wine

During malolactic fermentation (MLF), lactic acid bacteria influence aroma and flavor of wines by the production of volatile metabolites and the modification of aroma compounds derived from grapes and yeasts. In an effort to isolate these bacteria properties as advantages for winemaking, this study aimed to assess the relative contribution of two aspects: the effects of lactic acid bacteria activity on the volatiles compounds in Tannat wines and the consequences of aging in bottle on aroma compounds produced during MLF. To our knowledge, this is the first report related to the effect of wine aging in bottle on the aroma chemical compounds produced by MLF. Solid phase extraction complemented with chromatographic techniques was used to study the wine aroma compounds. A sensory evaluation of the wines was also performed through descriptive methods. We demonstrated modifications in the concentration of acetates, ethyl esters, and other secondary metabolites during MLF. Major sensorial differences between wines that had undergone MLF were also noted. In addition, some modifications detected in the composition of Tannat wines as a consequence of the aging in bottle contributed to the change in differences between wines with and without MLF and furthermore between strains. These changes probably influence its fruity character.

SENSORY DESCRIPTIVE ANALYSIS OF URUGUAYAN TANNAT WINE: CORRELATION TO QUALITY ASSESSMENT

ABSTRACT Tannat (Vitis vinifera L. cv. Tannat) was the main grape variety to be established in Uruguay, being the only country in the Americas where this grape is commonly found. Because of its small cultivation in the world, this variety has not been thoroughly studied, hence, considerable research and development on this variety is still needed. The aims of this study were to obtain the aroma and taste profiles of Tannat red wine by means of descriptive analysis and to correlate the quantitative sensory data to the quality assessment obtained through a small panel of fine wine consumers. The correlations obtained resulted in a useful tool in Uruguayan Tannat wine development. Results showed that an increment in yeasty, burned and earthy aromas resulted in lower quality scores, while high intensities of dried fruit, phenolic and berry aromas are desirable in this fine wine variety. As far as taste is concerned, astringency positively influences quality evaluation of flavor (attack, evolution and persistence), body and overall quality.

Terpene Compounds as Possible Precursors of 1,8-Cineole in Red Grapes and Wines

While the contribution of 1,8-cineole to the aroma of wine has been reported, it is a matter of controversy that the vineyards producing such wines are surrounded by Eucalyptus trees, which may contribute their essence to the grapes. However, experimental information presented in this paper suggests that 1,8-cineole can be produced by chemical transformation of limonene and alpha-terpineol, and this process may be responsible for the occurrence of Eucalyptus-like aroma in Tannat wines from vines not grown in the vicinity of Eucalyptus trees. A mechanism for the chemical transformation of these aroma compounds is proposed.

Changes in antioxidant capacity of Tannat red wines during early maturation

The prevention of pathologies associated with oxidative stress has been related to red wine consumption and antioxidant phenolic compounds have been suggested as being responsible of this effect. To study factors influencing the antioxidant capacity (AC) and phenolic composition of red wines, different viticulture, vinification and maturation processes of the red wine variety Tannat were studied. AC correlated with total polyphenol content at 1, 6 and 12 months post-fermentation times. In all wines studied, AC increased with aging although most of the phenolic families remained constant, suggesting the relevance of qualitative changes of these compounds for AC. Changes in field treatments such as etephon application, the timing of the application and variations in wine making techniques such as the use of S. cerevisiae var. ellipsoideus or a “color extractor” pectinolytic enzyme were the most effective in increasing AC.

Cytoprotection by Neutral Fraction of Tannat Red Wine against Oxidative Stress-Induced Cell Death

Some of the beneficial effects of the Mediterranean diet on human pathologies have been attributed to red wine polyphenols. It has been postulated that the antioxidant activity of the latter would be also responsible for the cytoprotective capacity of red wine that has been reported in a few papers. Nevertheless, red wine shows a complex composition, and the active fraction is not known yet. In this context, the protective capacity of total lyophilized extracts of red wine and anthocyanin, neutral, or acidic fractions, was explored in PC12 cells in culture after a hydrogen peroxide insult. Although all fractions showed high antioxidant activity, only the neutral fraction was cytoprotective. The analysis of this active fraction showed that it was rich in the aglycons quercetin and myricetin as well as the glycosides of kaempferol, isorhamnetin, epicatechin, and catechin, some of which are known to be cytoprotective. This is the first paper to reveal the active fraction of total wine responsible of its cytoprotection.

Anthocyanic Composition of Tannat, Cabernet Sauvignon and Merlot Young Red Wines from Uruguay

The anthocyanic composition of the 1996 and 1997 harvests of Merlot, Cabernet Sauvignon and Tannat red wines from Uruguay was studied through the determination of their delphinidin, cyanidin, petunidin, peonidin and malvidin glucoside content, together with the corresponding acyl derivatives. The anthocyanic profiles of each variety showed significant differences, which may be used in their classification. Wine distribution according to variety was verified through the application of discriminative analysis. The most important anthocyanins in varietal differentiation were the petunidin and malvidin glucosides, together with the acetyl esters of the petunidin, peonidin and malvidin glucosides, indicating the importance of the methoxylation for varietal differentiation. The total anthocyanin average content and most of the individual anthocyanins analysed were higher in the Tannat wines. The concentrations of delphinidin, petunidin and their derivatives apparently define the anthocyanic profiles of the Tannat wines as compared to the Merlot and Cabernet Sauvignon wines of Uruguay.