Wine quality: Correlations with colour density and anthocyanin equilibria in a group of young red wines

Following an exhibition of 32 current vintage red wines of two varieties from the Southern Vales district of South Australia, a correlation was observed between colour densities and the order of ranking previously assigned by a panel of experienced judges. There was no relation between wine colour density and anthocyanin content. Amongst many wines having comparable levels of anthocyanins, the variation in colour density was as much as 3.6-fold, and the degree of ionisation of the anthocyanin component of wine colour was found to range from 6 to 25%. These latter values were also correlated with the quality ratings. The data support the opinion that measurement of colour density and of the degree of ionisation of anthocyanins can provide an objective guide to organoleptic properties in young wines of the same variety and region. Confirmation for this view was obtained from other data concerning the subsequent vintage of Cabernet Sauvignon in the same district. Factors likely to be responsible for the varying states of anthocyanin equilibria in these wines are discussed in terms of wine composition and oenological practice.     

Nutraceutical value and toxicological profile of selected red wines from Morocco

The polyphenolic composition, antioxidant properties and multielement profile of selected red wines from Morocco were evaluated. The polyphenolic contents resulted higher than those reported elsewhere for the same variety of wines; the highest quantity was found in Cabernet Sauvignon, followed by Merlot, and last by Syrah wine. All of the wines tested showed very similar anthocyanin and flavonol patterns: individual compound contents resulted generally higher in comparison to conventional wines. The content of trans-resveratrol was significantly higher than that of cis-resveratrol in all of the wine samples. Particularly, Merlot showed the highest concentration of trans-resveratrol while Syrah exhibited the highest levels of cis-resveratrol. Reducing capacity resulted higher than antiradical property for all of the wines. The metal concentrations were below the official limits. The elemental pattern of wines were very similar, excepted V, Mn, Fe, Cu, As and Mo, for which Syrah markedly differed from the other wine samples.     

Polyphenolic composition of Spanish red wines made from Spanish Vitis vinifera L. red grape varieties in danger of extinction

Phenolic composition, chromatic characteristics, and antioxidant activity of young wines made from three minority red grape varieties (Moravia Dulce, Rojal and Tortosí) cultivated in the Spanish region of Castilla-La Mancha were studied over two vintages. Phenolic contents were affected by both grape variety and vintage, whereas phenolic profiles were mainly affected by grape cultivar, thus allowing their differentiation The anthocyanin profiles of Moravia Dulce and Tortosí wines were dominated by malvidin 3-glucoside, whereas peonidin 3-glucoside was in Rojal wines. The flavonol profile of Rojal and, in a lesser extent, Tortosí wines were dominated by B-ring di-substituted flavonols (mainly quercetin-type flavonols). In contrast, B-ring tri-substituted flavonols (mainly myricetin-type) predominated in Moravia Dulce wines. All studied wines had high quantities of total resveratrol, especially Rojal and Moravia Dulce wines, although they mainly occurred as cis-isomers. Rojal wines always appeared as the most different single-cultivar wines in all parameters in this study, being characterized by the lowest content of almost all families of phenolic compounds. With regard to the colour characteristics, all the studied wines had normal values to be considered young red wines except for Rojal wines, which should be considered as rosé wines. Finally, all wines showed remarkable antioxidant activity, closely connected with their phenolic content. The results suggest that Moravia Dulce and Tortosí grape cultivars could be appropriate raw materials for the elaboration of quality young red wines, whereas Rojal grapes could be for rosé wines.     

Free radical scavenging and antibacterial activities of southern Serbian red wines

Free radical scavenging and antibacterial activities were determined for several red wines from different grape varieties from the southern Serbia wine region. The amount of polyphenols and anthocyanins in selected wines was investigated and the potential antibacterial activity of the wines against pathogenic strains of Staphylococcus aureus and Escherichia coli was also determined. The free radical scavenging and antibacterial activity of the wines was correlated with polyphenolic and anthocyanin content. The significant differences in the antioxidant and antibacterial activities between the wines from grape cultivars (Cabernet Sauvingon and Pinot Noir) and the indigenous varieties (Vranac and Prokupac) were not confirmed. The hypothesis of a protective effect of red wine is supported by our results that show that the red wines with higher amounts of polyphenols and anthocyanins had higher antioxidant and antibacterial properties.     

Polyphenolic Composition and Antioxidant Activity of Galician Monovarietal Wines from Native and Experimental Non-Native White Grape Varieties

Galicia region (Northwestern Spain) wine production is mainly focused to high-quality white wines. The polyphenolic composition and the antioxidant activity have been determined to characterize the wines obtained from white grape varieties (Albariño, Branco Lexitimo, Caiño blanco, Godello, Loureiro, Torrontes, and Treixadura) grown in Galician protected production areas, and the wines elaborated with non-native varieties experimentally grown in Galicia (Chardonnay, Gewürztraminer, Pinot blanc, Pinot gris, Riesling, and Sauvignon blanc). Since Albariños are the varietal wines with the highest production and commercialization extension, we have studied their polyphenolic composition as a function of the production subarea. Three vintage years (2010, 2011, and 2012) have been considered to account for climate variability. Liquid chromatography with diode array and mass spectrometry detection was used to obtain the phenolic profiles. Wines from native grapes could be fully discriminated by their phenolic composition, with only Albariño being partially confused with other varietal wines. Albariño wines produced in O Rosal and Ribera do Ulla could be clearly differentiated, whereas Condado do Tea and Val do Salnés wines were partially confused. The polyphenolic profile was enough to differentiate the wines obtained from non-native grapes. The total polyphenols content and the antioxidant activity of white wines elaborated in Galicia were comparable, although significant differences were found among varieties.     

Influence of grape variety and their phenolic composition on vasorelaxing activity of young red wines

Red wine has been reported to exert beneficial effects in preventing cardiovascular diseases probably due to their polyphenols constituents. The vasorelaxant capacity and phenolic composition of four monovarietal young red wines Merlot, Tempranillo, Garnacha and Cabernet-Sauvignon obtained from grapes from 2004 vintage, cultivated under the same climatic and agricultural conditions, wine-making technology and storage conditions, were determined using vascular reactivity assay in rat aortic and high-performance liquid chromatography, respectively. Primary cultures of vascular smooth muscle cells from Wistar rats were also used to evaluate their survival prevention activity as well. Every studied wine present vasorelaxation effect, but the higher value corresponds to the analyzed Merlot wine, especially rich in phenolic compounds, mainly catechins and oligomeric proanthocyanidins and anthocyanin glycosides. This study further demonstrated previous investigations about the phenolic composition of wines relation with their vasorelaxation activity.     

Spectral evaluation of young red wines: Anthocyanin equilibria,total phenolics,free and molecular SO2, “chemical age”

Red wine colour is an integration of contributions from monomeric anthocyanins and polymeric pigment forms. Because of gross differences between the two fractions in their responses to pH change and to SO₂ addition, approximate measures of the states of anthocyanin equilibria in young red wines can be routinely made. Recent correlations of such measures with independent assessments of relative wine quality have prompted further examination and development of the original analytical concepts. The equilibria may be described in terms of two percentage parameters α and α ', the values of which are related to wine pH and to SO₂ added after fermentation. Measures of free SO₂ and also molecular SO₂, anthocyanin content and total phenolics are obtained from the same set of spectral data. The interpretations are based upon a number of analytical premises for which certain approximations have been necessary. These appear to be well justified in comparative evaluations because of the wide range of parameter values observed in surveys of current vintage wines. Observations of ageing changes in the composition of wine colour, with proposed spectral indices of “chemical age”, are also presented.     

Antioxidant and antimicrobial properties of polyphenolic fractions from selected Moroccan red wines

The present study is the first effort to a comprehensive evaluation of the antioxidant and antimicrobial activities of fractionated red wines from Morocco. The results obtained revealed that the wine samples were characterized by a higher phytochemical concentration than the same variety of wines with a different geographical origin and other more consumed red wines, confirming what was reported in a previous authors' work. The most phenolic-rich fractions were the ones containing phenolic acids and quercetin glucoronides from Syrah and Merlot wine samples while Cabernet Sauvignon exhibited the highest monomeric anthocyanin content. The antioxidant activity of wine extracts was tested by ferric reducing antioxidant power and 1,1-diphenyl-2-picrilhydrazyl assays. Samples revealed a higher reducing capacity than radical scavenging property and a good correlation between antioxidant activity and polyphenolic content values. As regards the antimicrobial properties, each fraction exhibited activity against a broad spectrum of food-borne microorganisms, revealing not only a moderate to high natural preserving capacity, but also potentially beneficial influence on human health. PRACTICAL APPLICATION: In consideration of the scarcity of data regarding composition and biological properties of Moroccan red wines, the present study may represent a valuable reference for wine consumers and producers.     

Chemometric studies of bottled wines with denomination of origin from the Canary Islands (Spain)

Seventeen physicochemical parameters including conventional enological parameters, polyphenolic parameters and volatile compounds were determined in 153 wines from the main wine producers belonging to the Canarian zones with Denomination of Origin (DO). Numerous significant correlations were found between the physicochemical parameters analysed. Applying the principal component analysis, the wines tend to separate on the basis of the type of wine. Besides, the dimension space was reduced to six principal components that explain 76.1% of the total variance. The principal component analysis of the red wines separated them as a function of vintage. Linear discriminant analysis (LDA) applied to all the wines, allowed a reasonable differentiation according to vintage, type of wine and island of production.     

中国东亚种红葡萄酒的颜色特征及酚类组成研究

为探究东亚种红葡萄酒的颜色特征以及酚类物质轮廓,采用分光光度法、酶标仪和高效液相色谱-串联质谱（HPLC-MS/MS）技术分别对3款东亚种、3款欧亚种及2款杂交种（山葡萄×欧亚种）红葡萄酒的颜色和酚类物质组成进行分析,并对其花色苷衍生物进行鉴定。结果表明,与欧亚种红葡萄酒相比,东亚种红葡萄酒的辅色花色苷含量较高（55.63%～55.66%）,而聚合花色苷含量较低（19.63%～27.01%）,并且花色苷含量较为丰富（399.30～829.95 mg/L）,以花色素-3,5-O-双葡萄糖苷为主（＞97.50%）,酰化花色苷较低（＜21.78%）。花色苷衍生物检测结果表明,东亚种红葡萄酒中的花色苷与（表）儿茶素聚合产物和吡喃花色苷的含量极低（痕量水平）。东亚种红葡萄酒在非花色苷酚组成上的突出特点为单体和二聚体黄烷醇的含量极低,因此其对酒体颜色的潜在影响可能较小。     

Influence of technological practices on biogenic amine contents in red wines

To investigate the enological factors associated with biogenic amine content in wines, 224 samples of red wine were industrially manufactured. Differences in the amines and corresponding precursor amino acids of these wines due to their producing cellar and vintage were examined. The main effects of some technological procedures in the biogenic amine content of these wines was also described using multifactor analysis of variance. The results of the study indicate that vintage can clearly influence the amine contents of wines. It was also noticed that some enological practices widely used to enhance wine quality, such as the ageing of wine on lees and, mainly, longer grape skin maceration, strongly increased biogenic amine concentration. However, the addition of pectolytic enzymes did not favour the accumulation of any biogenic amine. With this study, it was also possible to conclude that the inoculation of wine with commercial malolactic starters minimises the levels of biogenic amines.     

Aging of red wines made from hybrid grape cv. BRS Violeta: Effects of accelerated aging conditions on phenolic composition,color and antioxidant activity

Aging is an enological technique usually employed with Vitis vinifera wines for improving and stabilizing wine sensory attributes like red wine color. However, red wines made from non-vinifera grape cultivars are considered not suitable for classic wine aging because they are prone to color loss during processing and storage, mainly due to the major occurrence of non-acylated anthocyanidin 3,5-diglucosides. The recently developed hybrid grape cv. BRS Violeta gives rise to deep red-purplish colored wines characterized by an important contribution of p-coumaroylated anthocyanidin 3,5-diglucosides. In this work, Violeta red wines were subjected to control (storage at 15 °C) and accelerated (storage at 25, 35 and 50 °C) aging for 120 days. Total phenolic content was only significantly decreased by 23% in accelerated aged wines at 50 °C, whereas antioxidant capacity was mainly reduced in the first 20 days of aging (around 35% for all the wines, except for 45% for wine aged at 50 °C) and then remained almost stable. In contrast, total anthocyanin content decreased following expected first-order kinetics and the variation of rate constants with regard to temperature fitted well with an Arrhenius-type equation. The calculated activation energy for disappearance of anthocyanins (47 kJ/mol) was close to the lower limit of the range of values reported for thermal degradation of anthocyanidin 3-glucosides. In addition, half-life values for p-coumaroylated anthocyanidin 3,5-glucosides of Violeta wine aged at 50 °C almost doubled those of their corresponding non-acylated derivatives. The latter result is suggested to be the main reason behind the relatively high resistance of Violeta wine towards the disappearance of anthocyanin under accelerated aging conditions. Finally, chromatic characteristics of Violeta wines did not significantly change their C* values during aging but L* and h* values increased as expected, the latter mainly due to higher increases of the yellow color component (b*) over lower decreases of the red color component (a*). These color changes were more drastic in the accelerated aged wines and the wine aged at 25 °C still maintained interesting color characteristics close to those of the control aged wine that did not change very much.     

Use of stomatal conductance and pre-dawn water potential to classify terroir for the grape variety Kékfrankos

Background and Aims: A 3‐year study was carried out in order to evaluate the ecophysiology, yield and quality characteristics of Vitis vinifera L. cv. Kékfrankos (syn. Limberger) at Eger‐Nagyeged hill (steep slope) and at Eger‐K?lyuktet? (flat) vineyard sites located in the Eger wine region, Hungary. The aim of this paper was to analyse the effect of ‘vintage’ and ‘terroir’ on the seasonal changes of Kékfrankos ecophysiology and its possible relationship with yield and wine composition. Methods and Results: Grapevine physiological responses (midday‐ and pre‐dawn water potential, pressure–volume analysis and gas‐exchange), growing stages, yield and wine composition of each vineyard were studied. Lower grapevine water supply was detected at Eger‐Nagyeged hill in each season due to its steep slope and soil characteristics. Pressure‐volume curves indicated that there was no osmotic adjustment in the leaves of this variety. Higher osmotic concentration was measured at turgor loss and full turgor in the leaves of the unstressed vineyard (Eger‐K?lyuktet?) presumably due to higher photosynthetic activity. Differences in soil water content of the vineyards resulted in a slightly altered cell wall elasticity. Stomatal conductance, transpiration rate and photosynthetic production per unit leaf area were affected by water availability. Lower yield in Eger‐Nagyeged hill was partly associated with decreased photosynthetic production of the canopy. Improved wine quality of Eger‐Nagyeged hill was due to moderate water stress which induced higher concentration of anthocyanins and phenolics in the berries. The duration of the phenological stages was dependent on vintage temperature characteristics rather than on vineyard site. Conclusion: There was a close relationship between environmental conditions, Kékfrankos gas‐exchange, water relations, yield and wine composition. Water deficit plays an important role in creating a terroir effect, resulting in decreased yield, better sun exposure of leaves and clusters and thus higher concentration of phenolics and anthocyanins. Although quality is mainly influenced by vintage differences, vineyard characteristics are able to buffer unfavourable vintage effects even within a small wine region. Significance of the Study: Stomatal conductance, pre‐dawn water potential and climatic data may be reliable parameters for terroir classification, although variety–terroir interactions must always be considered.     

Phenolic and Anthocyanin Profile of Valea Calugareasca Red Wines by HPLC-PDA-MS and MALDI-TOF Analysis

The quality of red wines is given by phenolic compounds and anthocyanins and is associated with colour, taste and therapeutic effects on human health. This work aims to provide a detailed profile of phenolic compounds and anthocyanins that are found in five red wine samples from Dealu Mare-Valea Calugareasca region. The phenolic and anthocyanin profiles of the red wine samples were determined by high-performance liquid chromatography-photodiode array-mass spectrometry and matrix-assisted laser desorption/ionisation–time of flight, respectively. The results obtained showed that Feteasca Neagra had the highest content of phenolic compounds followed by Pinot Noir while the preponderant compound was gallic acid. Amongst anthocyanins, malvidin was found to be the major compound and the highest anthocyanin content was found also for Feteasca Neagra wine. A simple high-performance liquid chromatography-photodiode array-mass spectrometry method was developed, optimised and applied for the quantification of phenolic compounds in red wine samples from Dealu Mare-Valea Calugareasca region. In the same time, a rapid matrix-assisted laser desorption/ionisation–time of flight method that does not need sample preparation was applied for the identification of anthocyanins. Moreover, the phenolic and anthocyanin composition of red wines from Dealu Mare-Valea Calugareasca region is reported for the first time. The phenolic and anthocyanin profile determination will be beneficial for the Romanian winemakers to produce high-quality red wines.     

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

The 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.     

Comparison of chemical composition and antioxidant capacity of commercially available blueberry and blackberry wines in Illinois

Moderate wine consumption may reduce the incidence of certain age-related chronic diseases such as heart disease, hypertension, metabolic disease, and neurodegenerative disease. Blueberry and blackberry wines commercially available in Illinois were evaluated for chemical and quality components relevant to consumers in order to study their potential health benefits. Total polyphenolic content was measured by the Folin-Ciocalteu method, total anthocyanin content by the pH differential test, and in vitro antioxidant capacity (AC) by the oxygen radical absorbance capacity (ORAC) method. Color was measured using Hunter colorimetry and quality parameters including pH, °Brix, acid content, glucose-fructose, and percent alcohol were measured using Fourier transform infrared spectroscopy. Blackberry wines (n= 6) had an average total polyphenolic content of 2212.5 ± 1090.3 mg ellagic acid equivalents (EAE) per liter, total anthocyanin content of 75.56 ± 70.44 mg/L, and AC of 26.39 ± 17.95 mmol trolox equivalents (TEs) per liter. Blueberry wines (n= 4) had an average total polyphenolic content of 1623.3 ± 645.5 mg EAE per liter, total anthocyanin content of 20.82 ± 12.14 mg/L, and AC of 21.21 ± 7.71 mmol TE per liter. Strong positive correlations were found between °Brix and glucose-fructose concentration (r= 0.90), total acid and malic acid (r= 0.90), and between total polyphenols and AC (r= 0.88). The results suggest that fruit wines made from blueberries and blackberries may have potential health applications and therefore could contribute to the economy of the wine industry. PRACTICAL APPLICATION: The majority of wines are produced from grapes, but wine can also be produced from other fruits including blueberries and blackberries, which contain phenolic compounds that may contribute to human health. A comparative evaluation was conducted on commercial nongrape fruit wines and parameters related to their health benefits. Fruit wines made from blueberries and blackberries may have potential health applications and therefore could contribute to the economy of the wine industry.     

Wine tartrate stabilization by different levels of cation exchange resin treatments: impact on chemical composition,phenolic profile and organoleptic properties of red wines

The aim of this work was to evaluate the impact of cation exchange resin, on tartrate stabilization, chemical composition, general phenolic composition, individual anthocyanin and different proanthocyanidin fraction content of a red wine made from a mixture of three Portuguese red grape varieties. Additionally, the influence of this tartrate stabilization process on organolpetic properties was another aim of this work. The cation exchanged red wines were mixed in different proportions with the untreated red wine. The results showed that the application of a cation exchange resin used was useful to adjust the pH and total acidity and revealed a good capacity to retain potassium and calcium. In addition, the cation exchange resin treatment caused a significant decrease in the contents of individual anthocyanins well as in the different fractions of proanthocyanidins (especially in monomeric fraction). Finally, considering the organoleptic properties, the most highly evaluated wine, especially considering taste parameters, was the control wine. These results confirm that cation exchange is an interesting in red winemaking to improve tartaric stability, but at same time it is important analyze potential effects on phenolic content and organoleptic properties of red wines.     

Comparative studies on the antioxidant properties and polyphenolic content of wine from different growing regions and vintages,a pilot study to investigate chemical markers for climate change

Many health benefits of wine result from specific polyphenolic compounds. Factors such as climate, CO₂ levels and region are known to affect polyphenolic compounds in wine; therefore a pilot study was conducted to focus on the Australian climate which has shifted from El Niño to La Niña. This research paper presents the influence of climate conditions and growing regions on the in vitro and ex vivo antioxidant capacity of red and white wine and the profile and concentration of polyphenols in these wines from the 2008 and 2009 vintages. The ORAC and polyphenolic data show that warmer climate wines had lower in vitro antioxidant capacity values but retained good bioavailability based on data from the RBC ex vivo assay compared to cool climate wines. Based on this pilot study, further research is being conducted at the National Measurement Institute, Australia (NMIA) with the goal of determining more polyphenolic compounds which appear to be affected by climate conditions.     

Effect of the prefermentative addition of copigments on the polyphenolic composition of Tempranillo wines after malolactic fermentation

The influence of the prefermentative addition of copigments and different winemaking technologies on the polyphenolic composition of Tempranillo red wines after malolactic fermentation was studied. Six experiments dealing with the prefermentative addition of caffeic acid, rutin, (+) catechin, white grape skin tannin, white grape seed tannin and control wines were realised. Three different winemaking technologies (traditional vinification, prefermentative cold maceration at 6–8 °C and cold soak at 0–2 °C with dry ice) were studied. Prefermentative addition of copigments increases anthocyanin copigmentation reactions and produces wines with a greater colour, a higher anthocyanin concentration, a superior contribution of anthocyanins to the colour of the wine, a superior percentage of tannins polymerised with polysaccharides and less astringency. Cold prefermentative maceration increases the extraction of polyphenols, the anthocyanin copigmentation reactions and the polymerisation reactions between tannins and polysaccharides. The effectiveness of the combination of copigments and prefermentative maceration treatments was demonstrated by the increase of the concentration of the polyphenolic compounds.     

Comparison of fining red wines with purified grape pomace versus commercial fining agents: effect on wine chromatic characteristics and phenolic content

The large quantity of grape pomace (seeds, skin, and peduncle) produced during the winemaking process can be a problem and the search for procedures which could permit their valorisation is considered an important issue. This study investigates the use of purified grape pomace as a fining agent for reducing the level of some wine phenolic compounds, especially tannins. For this, purified grape pomace was applied to three young red wines of different phenolic composition and the results were compared with the effect of some common commercial fining agents. The results demonstrated that grape pomace can be used to decrease the wine tannin content with similar results to those obtained with casein, while also reducing anthocyanin content although to a similar extent to when bentonite is used. The effect of purified Monastrell grapes pomace is similar in the three different studied wines although it affected the most to wines with high monomeric anthocyanin content.