Phenolic Composition Of Red Wines Research Articles

Incidence of the Winemaking Technique on Metal Content and Phenolic Composition of Red Wines

The influence of different winemaking techniques usually used to elaborate red wines (Ganimede, prefermentative maceration, pectolytic enzymes and tannins addition, oak chips addition, delestage, and conventional procedure) on the metal content was evaluated. Linear discriminant analysis was also used to characterize the respective wines based on the metal content. By using iron, manganese, and calcium as chemical descriptors, the six winemaking techniques were perfectly discriminated. As the phenolic composition is an important quality factor in red wines, a correlation study between phenolic compounds and metals was also performed. A good correlation has been found for iron, calcium, and potassium with total polyphenols, tannins, and flavanols reactive. Iron, zinc, calcium, and potassium showed a significant correlation with anthocyanin compounds. Furthermore, higher concentrations of iron and calcium, but lesser ones of potassium, permitted to obtain red wines with a greater chromatic intensity.

Investigation of the effect of gelatine, egg albumin and cross-flow microfiltration on the phenolic composition of Pinotage wine

The effect of fining and cross-flow microfiltration on the phenolic composition of red wine was investigated. Both gelatine (G) and egg albumin (EA) fining decreased the mean degree of polymerisation (mDP) of tannin significantly by 26.4% and 25.2%, respectively, compared to the control (C). Cross-flow microfiltration (CF) also decreased the mDP significantly by 25%. Thus, the fining agents and cross-flow microfiltration selectively removed the highly polymerised phenols. After 3.5months of bottle ageing, differences between the different treatments and the control decreased. CF had the most significant effect on the flavan-3-ol and polymeric phenol (tannin) content of the wines compared to the control followed by G fining. CF and EA treatments significantly decreased the total pigment content compared to C. CF was also the only treatment that could be distinguished from the other treatments by sensory analysis. All treatments improved clarity of the wines with cross-flow microfiltration having the largest effect.

Phenolic Compositions of 50 and 30 Year Sequences of Australian Red Wines: The Impact of Wine Age

The phenolic composition of red wine impacts upon the color and mouthfeel and thus quality of the wine. Both of these characteristics differ depending on the age of a wine, with the purple of young wines changing to brick red and the puckering or aggressive astringency softening in older wines. This study investigated the color parameters, tannin concentrations and tannin composition of a 50 year series of Cabernet Sauvignon wines from a commercial label as well as 30 year series of Cabernet Sauvignon and Shiraz wines from a separate commercial label to assess the impact of wine age on phenolic composition and concentration. The wine color density in wines of 40 to 50 years old was around 5 AU compared with 16 AU of wine less than 12 months old, which correlated well with the concentration of non-bleachable pigments and pigmented polymers. Conversely, the anthocyanin concentrations in 10 year old wines were substantially lower than that of recently bottled wines (around 100 mg/L compared with 627 mg/L, respectively), adding further evidence that non-bleachable pigments including pigmented polymers play a much larger role in long-term wine color than anthocyanins. No age-related trend was observed for tannin concentration, indicating that the widely noted softer astringency of older red wines cannot necessarily be directly related to lower concentrations of soluble wine tannin and is potentially a consequence of changes in tannin structure. Wine tannins from older wines were generally larger than tannins from younger wines and showed structural changes consistent with oxidation.

Phenolic characterisation of red wines from different grape varieties cultivated in Mendoza province (Argentina)

Knowledge of the chemical composition of wine and its association with the grape variety/cultivar is of paramount importance in oenology and a necessary tool for marketing. Phenolic compounds are very important quality parameters of wines because of their impact on colour, taste and health properties. The aim of the present work was to study and describe the non-flavonoid and flavonoid composition of wines from the principal red grape varieties cultivated in Mendoza (Argentina). Sixty phenolic compounds, including phenolic acids/derivatives, stilbenes, anthocyanins, flavanols, flavonols and dihydroflavonols, were identified and quantified using high-performance liquid chromatography with diode array detection coupled with electrospray ionisation mass spectrometry (HPLC-DAD/ESI-MS). Marked quantitative differences could be seen in the phenolic profile among varieties, especially in stilbenes, acylated anthocyanins and other flavonoids. The polyphenolic content of Malbec wines was higher compared with the other red varieties. Dihydroflavonols represent a significant finding from the chemotaxonomic point of view, especially for Malbec variety. This is the first report on the individual phenolic composition of red wines from Mendoza (Argentina) and suggests that anthocyanins, flavanols and phenolic acids exert a great influence on cultivar-based differentiation.

Evolution of Phenolic Composition of Red Wine during Vinification and Storage and Its Contribution to Wine Sensory Properties and Antioxidant Activity

The objective of this work was to study the evolution of the phenolic composition of red wine during vinification and storage and its relationship with some sensory properties (astringency and bitterness) and antioxidant activities. Thus, red wine was made by a classic vinification method with Castelão and Tinta Miúda grapes (Vitis vinifera L.) harvested at maturity (3:2; w/w). Samples were taken at 2 and 7 days of maceration, at second racking, at the time of bottling and at 6 and 14 months after bottling. The total polyphenols extract (TPx) in each sample was isolated by column chromatography. The phenolic composition (anthocyanins and proanthocyanidins), in vitro antioxidant activity, and sensory property (astringency, bitterness) of the isolated TPx from different winemaking stages were evaluated through high-performance liquid chromatography-diode array detection, 1,1-diphenyl-2-picrylhidrazyl radical test, ferric reducing antioxidant power assay, total phenolic index, MWI (polyphenol molecular weight index), TSA (tannin specific activity), and sensory panel tasting. The results showed that the phenolic composition of red wine varied significantly during winemaking. The intensity of astringency (IA) and the intensity bitterness (IB) of the isolated TPx from different winemaking stages increased from 2 days of maceration until second racking and then decreased. Furthermore, MWI and TSA are positively correlated with IA and IB. The in vitro antioxidant activity of the isolated TPx from different winemaking stages maintained unchanged after alcoholic fermentation, which was independent of the variation of phenolic composition and sensory properties.

Effect of Addition of Commercial Grape Seed Tannins on Phenolic Composition, Chromatic Characteristics, and Antioxidant Activity of Red Wine

The effect of addition of grape seed tannins on the phenolic composition, chromatic characteristics, and antioxidant activity of red wine was studied. Two highly pure commercial grape seed tannins (GSE100 and GSE300) were selected, and their phenolic compositions were determined. Two types of red wines were made with Castelão/Tinta Miúda (3/2, w/w) grapevine varieties by fermentation on skin using two different maceration times, which correspond to the wines rich and poor in polyphenols, respectively. Each of these wines was used for experimentation with the addition of GSE100 and GSE300 before and immediately after alcoholic fermentation. Phenolic composition, chromatic characteristics, and antioxidant activity of the finished red wines were analyzed by HPLC-DAD, CIElab 76 convention, and DPPH radical test, respectively. The results showed that the addition of grape seed tannins had obvious effects of increasing color intensity and antioxidant activity only in the wines poor in polyphenols. Although GSE300 contained much higher amounts of di- and trimer procyanidins and a lower amount of polymeric proanthocyanidins, it provided effects of increasing the color intensity and antioxidant activity of the wines poor in polyphenols similar to those of GSE100. Furthermore, GSE100 released more gallic acid to wines than GSE300, although no gallic acid was detected in GSE100. Tannins added after alcoholic fermentation had a better effect on phenolic composition of red wine than tannins added before alcoholic fermentation.

Effect of principal polyphenolic components in relation to antioxidant activity in conventional and organic red wines during storage

Wine phenolic composition depends on the grapes used to make the wine and on the vinification conditions and a wide range of variables such as cultivar, viticulture practices and vinification techniques can affect the phenolic composition of red wines. Changes in polyphenol content and antioxidant activity during storage over 6 months in bottles were studied in Monastrell varietal red wines from grapes obtained by organic and conventional agricultural practices. Also it was studied the relationship between antioxidant activity and phenolic compounds. The results showed that the contents of anthocyanins decreased during storage although hydroxycinnamics derivatives, stilbenes and flavonols do not suffer significative changes. The total antioxidant activity of conventional and organic wines was well correlated especially with anthocyanins at first month of storage and flavonols all time. Stilbenes had a high correlation with antioxidant activity in both types of wine especially in the last month of storage (r 2 = 0.74), and hydroxycinnamic derivatives had a poor correlation with antioxidant activity. Evolution of phenolics compounds and antioxidant activity in conventional and organic wines were similar during storage. Not significant differences were observed in conventional and organic wines.

Influence of training system on chromatic characteristics and phenolic composition in red wines

Chromatic characteristics and phenolic composition of red wines elaborated from Souson and Brancellao grapes (Vitis vinifera L.), whose vines were trained in cordon and Guyot systems, were determined. This comparison was possible because there were no significant differences between yields for each one. Hue was the only significantly different chromatic parameter for both training systems and cultivars. In Souson cultivar, saturation, colour intensity and red percentage were greater for Guyot system. Souson cultivar trained in Guyot system and Brancellao cultivar trained in cordon system were characterized by higher total anthocyanin concentration. However, greater ionization index and flavanols reagent with dimethyl aminocinemaldehyde were associated with Guyot and cordon systems, respectively, independently on cultivar. Furthermore, gentisic acid, as well as malvidin-3-glucoside, petunidin-3-acetylglucoside and malvidin-3-caffeoylglucoside in less extension, permitted to differentiate training systems in both Souson and Brancellao cultivars. Principal component analysis was also performed for a better understanding of the differences found.

The influence of oak wood chips, micro-oxygenation treatment, and grape variety on colour, and anthocyanin and phenolic composition of red wines

The development of the micro-oxygenation technique and the positive results obtained in the quality of red wines have given rise to combining this technique with the addition of wood pieces, which would be a good combination for improving wine quality. The aim of this work was to study the combined effect of different chips and the application of micro-oxygenation before malolactic fermentation on colour and phenolic composition of red wines. Four different types of chips and two single-varietal red wines were used, studying the influence of chip type, grape variety, micro-oxygenation and storage time. Individual anthocyanins, phenolic compounds and colour parameters were evaluated and multivariate analyses were performed. The results obtained pointed out that grape variety and micro-oxygenation had more influence on phenolic composition and wine colour than the type of chips used to macerate the wines. Although some differences were found in these parameters and compounds based on chip type used, it can be said that the selection of one chip or another does not modify the chromatic characteristics of red wines.

A Review of the Effect of Winemaking Techniques on Phenolic Extraction in Red Wines

Winemaking variables and techniques are known to affect the phenolic composition of red wines. This review surveys the current literature on the impact of processing and fermentation parameters on the phenolic profile of the finished wines. Six winemaking variables and techniques have been reported to increase phenolic concentration: fermentation temperature, thermovinification, must freezing, <i>saignée</i>, pectolytic enzyme treatments, and extended maceration. In contrast, sulfur dioxide levels and cold-soak treatments have frequently been shown to have no or little lasting effect or to lead to a decrease in phenolic levels. Finally, carbonic maceration, yeast selection, and skin and juice mixing practices have produced variable results depending on the grape varieties studied.

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.

Phenolic compounds in red wine digested in vitro in the presence of iron and other dietary factors

Quantitative and qualitative changes in the phenolic composition of red wine may occur during digestion in the lumen, particularly when other dietary components are present. In this study, mixtures of red wine, iron, and ascorbic acid, meat or casein were subjected to a simulated gastrointestinal digestion. This process involves incubation of samples for 4.5 h at 37°C, at different pH values, in the presence of peptic enzymes and fractionation of digests through a dialysis membrane with a molecular weight cut-off of 6000–8000. Selected phenolic compounds were determined in undigested samples and in their dialysable digests by reversed-phase high-performance liquid chromatography. A dramatic decrease in the concentration of the selected phenolic compounds was observed in all samples after they were digested in vitro. Moreover, when iron and/or protein were added to red wine samples, changes in the phenolic profile of the undigested and of the in vitro digested samples were detected. These results suggest that interactions between red wine phenolic compounds and iron, protein and/or digestion components are important determinants of the physicochemical properties and the concentration of these phenolic compounds in the lumen. The in vitro methodology employed herein offers a tool for the study of phenolic compounds under conditions of simulated gastrointestinal digestion, incorporating lumenal events that may affect phenolic compounds.

Analysis of non-coloured phenolics in red wine: Effect of Dekkera bruxellensis yeast

The non-coloured phenolic composition of red wine obtained from Touriga Nacional grapes growing in the Dão region (Portugal) was determined by HPLC/DAD and 16 compounds were identified and quantified. The effect of nine different Dekkera bruxellensis strains on the levels of phenolic acids and flavonoids of the wine were also evaluated. In all samples (inoculated and non inoculated), phenolic acids predominated over flavonoids. In inoculated samples a considerable rise in the amounts of gallic acid was observed (about 33%) while the amounts of t-CAFTA, t-COUTA, caffeic and p-coumaric acids suffered a statistically significant decrease.

In vitro antioxidant activity of red grape skins

Phenolic antioxidants seem to be partly responsible for the protective effects against cardiovascular diseases attributed to moderate wine consumption. Grape skins greatly contribute to the phenolic composition of red wine. In this paper, the in vitro antioxidant activity of red grape (Vitis vinifera) skins is determined. We show that the radical scavenging activity (C50 values) against 2,2-diphenyl-1-picrylhydrazyl (DPPH·) of grape skin extracts is relatively high (3.2–11.1 mg dried skin/mg DPPH·) in relation to other foodstuffs and, as expected, is influenced by grape variety, stage of grape ripening and vintage. The antioxidant potential of grape skins seems to be transferred into wine since grape varieties with skins exhibiting high antioxidant potential also resulted in wines with high antioxidant activity. Statistically significant correlations were found between antioxidant activity and phenolic content (total polyphenols, proanthocyanins, catechins and anthocyanins) for both grape skins and wines.

Compositional changes during the storage of red wines treated with pectolytic enzymes: low molecular-weight phenols and flavan-3-ol derivative levels

The present work studies the effects of the addition of several commercial pectolytic enzyme products on the phenolic composition of red wine. Low-molecular-weight phenols and flavan-3-ol derivatives were studied. The results revealed that the addition of enzymes produced an overall increase in the extraction of these compounds. However, in the case of flavan-3-ol derivatives, extraction was increased only when sufficient time was allowed for maceration. Study of the evolution of the contents of these compounds over time suggested that, in general, wines that initially contain higher amounts of phenolic compounds are able to maintain higher levels of these compounds during storage.

Effect of grape processing on selected antioxidant phenolics in red wine

Wine, particularly red wine, is an important source of polyphenols and several studies have shown that moderate wine consumption is associated with a reduced risk of coronary heart disease. It has been hypothesized that these antioxidant compounds may be responsible for the potential beneficial effects of wine. The influence of different vinification techniques (fermentation on skin [A], mash heating [B], and the combination of both [C]) on the antioxidant capacity and the phenolic composition of red wines (Spätburgunder [Pinot Noir], Lemberger, and Cabernet Franc) were tested in the present study. The highest concentrations of anthocyanins, flavan-3-ols, flavonols, stilbenes, and antioxidant capacity were found in the red wines which were produced under the conditions of C, followed by B and A.

Effect of oxygenation on polyphenol changes occurring in the course of wine-making

The influence of controlled oxygenation on the colour and phenolic composition of red wine was studied by UV–VIS spectrophotometry, liquid chromatography (LC) coupled to diode array detection (DAD) and electrospray ionisation mass spectrometry, and thiolysis. The comparison between the control and oxygenated wines demonstrated changes in colour characteristics along with a significant increase in concentrations of pyranoanthocyanins, ethyl-bridged compounds and derived pigments both with storage time and with oxidation. Principal component analysis was applied to wine analysis data measured throughout the conservation period. The effect of the storage time and oxygenation was clearly reflected in this analysis. Mass-spectrometric analysis of the wines demonstrated the presence of compounds which are markers of reactions involving acetaldehyde. Two types of mechanisms were observed. The first concerns acetaldehyde condensation reactions and the second, the cycloaddition process between anthocyanins and flavanols mediated by acetaldehyde, generating tannin-pyranoanthocyanins. The presence in wines of trimeric structures resulting from these mechanisms, as well as the results obtained after thiolysis of the fraction containing polymeric species obtained by Fractogel chromatography, confirm that proanthocyanidins react with acetaldehyde in the same way as flavanol monomers.

First results about use of a possible substitution product for sulfur dioxide in wine making

&lt;p style="text-align: justify;"&gt;Plant extract DF100, produced by Chemie Research and Manufacturing Co. (Casselberry, Florida-U.S.A.) from wastes of grapefruit (&lt;em&gt;Citrus paradisi sp.&lt;/em&gt;) juice elaboration, presents anti-microbial and anti-oxydant properties. First experiments to use it to substitute sulfur dioxide in wine-making have been realized during two years.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;When DF100 is added in must at low level (less than 1 g/l), it does not influence growth and activity of yeasts.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;Wines obtained only differ on several fermentation secondary products as propanediol. This compound is all-ways more produced in the presence of DF100.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;Phenolic composition of red wines is weakly modified. Lowest anthocyanin extraction is balanced by a greater color, resulting from a higher ionization degree without sulfur dioxide.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;Plant extract ensures a good protective effect against bacterial alterations during wine ageing in wood casks.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;For highest concentrations, especially for stopping fermentation to obtain natural sweet white wines, plant extract leads to organoleptic deviations in color and taste.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;lt is necessary to follow study on this plant extract and to develop new preparation with a more purified and colourless product, hoping that toxicological studies will demonstrate its harmlessness.&lt;/p&gt;