Chemical and sensory evaluation of Bordeaux wines (Cabernet-Sauvignon and Merlot) and correlation with wine age

Effect of low molecular weight phenols on the in-mouth sensory perception of high molecular weight phenols by analyzing reconstituted wines

This research aimed to assess the contribution of monomeric phenols to the perception of bitterness and astringency by means of wine reconstitution experiments. Six wines with distinct total polyphenol indexes were selected and fractioned by preparative liquid chromatography into two fractions. Thirty-one reconstituted wines were prepared by combining distinct low molecular weight fractions (L) with different high molecular weight fractions (H). In-mouth attributes of reconstituted and reference wines were described by a trained sensory panel. Fractions were chemically characterized by UPLC-MS. No significant differences among sensory results were found between reference and reconstituted wines. Bitterness and astringency perception were strongly influenced by total proanthocyanidins content. Flavan-3-ol monomers and dimers were only responsible for astringency in wines with a low content of proanthocyanidins, as was the case in rosé wine. Quercetin-3-O-glucuronide and several anthocyanins presented correlations with bitterness in the reconstituted wines; notwithstanding, several interactions with this attribute were observed.

Enriched Red Wine: Phenolic Profile, Sensory Evaluation and In Vitro Bioaccessibility of Phenolic Compounds

The beneficial health effect of red wine depends on its phenolic content and the phenolic content in red wines is affected by ecological, agricultural, and enological practices. Enriched wines have been proposed as an alternative to increase the phenolic content in wines. Nevertheless, phenolic compounds are related to the sensory characteristics of red wines, so enrichment of red wines requires a balance between phenolic content and sensory characteristics. In the present study, a Merlot red wine was enriched with a phenolic extract obtained from Cabernet Sauvignon grape pomace. Two levels of enrichment were evaluated: 4 and 8 g/L of total phenolic content (gallic acid equivalents, GAE). Wines were evaluated by a trained panel to determine their sensory profile (olfactive, visual, taste, and mouthfeel phases). The bioaccessibility of phenolic compounds from enriched red wines was evaluated using an in vitro digestive model and phenolic compounds were quantified by High Performance Liquid Chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). Enrichment increased mainly flavonols and procyanidins. Such an increase impacted astringency and sweetness perceived by judges. This study proposes an alternative to increase the phenolic content in wines without modifying other main sensory characteristics and offers a potential beneficial effect on the health of consumers.

Decoding the Proanthocyanins Profile of Italian Red Wines

The Italian wine appellations system is organized in hundreds of origin wines, with unique characteristics that are protected with many denominations of origin. The aim of this work was to analyze and compare the proanthocyanin profile of 12 single-cultivar and single-vintage Italian red wine groups (Aglianico from Campania, Cannonau from Sardinia, Corvina from Veneto, Montepulciano from Abruzzo, Nebbiolo from Piedmont, Nerello Mascalese from Sicily, Primitivo from Apulia, Raboso Piave from Veneto, Sagrantino from Umbria, Sangiovese from Tuscany and Romagna, and Teroldego from Trentino), each one produced in their terroirs under ad hoc legal frameworks to guarantee their quality and origin. All wines were analyzed with a protocol that combined the phloroglucinolysis reaction with an LC-MS/MS instrument. The results underlined Sagrantino wines as the richest in proanthocyanins. Sangiovese, Montepulciano, Nerello, and Teroldego were the richest in B-ring trihydroxylated flavan-3-ols, and especially Nerello was the richest in prodelphinidins. Cannonau, Raboso Piave, Nerello, and Corvina were characterized by C-ring trans conformation flavan-3-ols. Nebbiolo and Corvina had high percentages of galloylated flavan-3-ols. Aglianico and Primitivo had the lowest percentages of B-ring trihydroxylated and C-ring trans conformation flavan-3-ols. This information should be useful in better understanding the Italian red wines and valorize them.

Comparative Evaluation of Physicochemical, Antioxidant, and Sensory Properties of Red Wine as Markers of Its Quality and Authenticity

The consumption of red wine by most wine drinkers has increased significantly because of the perceived health benefits which are linked to its inherent quality characteristics. In the quest to determine the conformity of Nigeria's domestic red wine quality with their international counterparts, the quality characteristics of domestic red wines produced in Nigeria were evaluated using foreign red wines as markers of wine quality and authenticity. Foreign and domestic red wines obtained in Nigeria were analyzed for physicochemical, antioxidant, and sensory properties using standard methods. Results showed that the domestic wines had significantly (p < 0.05) higher pH (4.03-4.16) and total sugar content (8.60-9.27%) while the foreign wines had significantly (p < 0.05) higher total titratable acidity (0.76-0.83%), Brix (6.98-8.04 g/100 g), alcohol (14.44-15.21% ABV), and polyphenol content (385.13-412.75 mg/L). Additionally, the domestic wines exhibited significantly (p < 0.05) lower antioxidant capacity compared to the foreign wines. Although the wines' hue angle (27.68°-41.46°) indicated a red colour spectrum in the visible region of the opponent colour chart, the total colour difference (ΔE) between foreign and domestic wines was significant. The sensory characteristics of the wines differed significantly as the panelist rating for overall acceptance ranged from 5.58 to 7.33. This research has provided valuable insight that the domestic wines studied showed a considerable level of authenticity and different levels of quality according to their varying concentration of organic acids, residual sugars, and phenolic compounds.

The effects of regions and the wine aging periods on the condensed tannin profiles and the astringency perceptions of Cabernet Sauvignon wines

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Thirty-two commercial red wines of Cabernet Sauvignon produced in five continuous vintages (2015–2019) and collected from four production regions were statistically different for the analyzed condensed tannin profiles.

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Cabernet Sauvignon wines from four regions were rich in the (–)-epicatechin as the extension subunit.

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Condensed tannin profiles could be used to distinguish some of the production region, but the different vintage samples were not well differentiated.

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A negative correlation of ageing periods and condensed tannin concentration of Cabernet Sauvignon wines was observed.

This study sought to determine the effects of wine-producing regions and aging periods on the astringency and chemistry of condensed tannins of Cabernet Sauvignon dry red wines. A wine quality study was performed with 5 vintages of 32 Cabernet Sauvignon wines produced in four Chinese wine-producing regions, Hebei (H), Xinjiang (X), Inner Mongolia (NM), and Ningxia (NX). Condensed tannin profiles were assessed by high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD). The (–)-epicatechin as the terminal subunit (tEC) is the major differential component between regions. Correlation analysis revealed that condensed tannin concentration and composition significantly affected the sensory evaluation of astringency. Condensed tannin concentrations were significantly and negatively correlated with wine aging periods. However, no significant correlation was found between aging periods and condensed tannin subunits (as mole%) composition. The current findings enhance the understanding of condensed tannins' chemical and astringency characteristics in Cabernet Sauvignon wines.

Volatile composition and sensory properties of wines from vineyards affected by iron chlorosis

Recent studies have shown that mild to moderate iron chlorosis can have positive effects on grape quality potential, including volatile profile. The main objective of this work was to investigate, for the first time, how moderate iron stress in grapevines affects the presence of volatile organic compounds (VOCs) in wines. The study was carried out during 2018-2019 seasons, in 20 Tempranillo vineyard subzones with different degree of iron deficiency, located in Ribera del Duero (North-Central Spain). The results showed that moderate iron stress increased in wines the concentrations of VOCs associated with floral notes, such as 2-phenylacetaldehyde, 2-phenylethanol and 2-phenylethyl acetate, while reducing the presence of C6-alcohols, responsible for green-herbaceous aroma. A favourable reduction of pH and a betterment of parameters related to colour were detected in wines from iron deficient subzones. Chlorosis incidence was associated to improvements in wine sensory attributes as layer intensity, black fruit and aroma intensity.

Monitoring of the Wines’ Quality by Gas Chromatography: HSS-GC/FID Method Development, Validation, Verification, for Analysis of Volatile Compounds

One of the most common techniques for wine analysis is gas chromatography coupled with the flame ionization detector and headspace autosampler (HSS-GC/FID) for the analysis of the volatile compounds in the wine samples. The main goal of this thesis was to develop the method for the analysis of volatiles (methanol, higher alcohols, and esters) in wine samples made of Cabernet Sauvignon and Merlot. Validation parameters were: r2 > 0.995; LOD (0.2–1.0 mg/L); CV (2.7–6.3%), and recovery (92–106%). Average contents of the methanol (198.0 mg/L and 150.5 mg/L), higher alcohols (398.5 mg/L and 335.8 mg/L), ethyl acetate (42.0 mg/L and 55.6 mg/L), and acetaldehyde (23.3 mg/L and 16.1 mg/L) were determined for Merlot and Cabernet Sauvignon, respectively. Based on the obtained results, it was concluded that the content of methanol is in direct connection with the type of grape used for preparation of the wine. It was also found that the duration of the maceration directly influenced the content of the methanol and higher alcohols. On the other hand, type of grape appeared not to have influence on the content of ethyl acetate and acetaldehyde in wines. The post hoc Tukey’s HSD test at 95% confidence limit showed significant differences between observed samples. Principal Component Analysis (PCA) was used for assessing the effect of different genotypes and extraction methods on wine samples. Using PCA of observed samples, the possible directions for improving the quality of product can be realized.

In-mouth attributes driving perceived quality of Pinot noir wines: Sensory and chemical characterisation

We investigated perception of mouthfeel in Pinot noir wines and its physicochemical determinants. Seventeen wine professionals judged 18 Pinot noir wines via two tasting tasks, Descriptive Rating and Directed Sorting, the latter based on perception of in-mouth attributes. Selected chemical measures of the same 18 wines were determined. Sensory results demonstrated that mouthfeel attributes driving high quality were smoothness/silky/velvety, volume/fullness/roundness, overall body, and viscosity/mouth-coating, while the taste of bitterness and perceived tannin harshness drove low quality judgments. Perceived astringency and expressions of tannin (e.g., soft; harsh; fine) drove sorting behaviour of participants. Partial least squares regression (PLSR) was used to associate perceived in-mouth phenomena and chemical composition. The phenolic profile, in particular tannin concentration and structure, was the most important predictor of astringency and its sub-components. These results have important implications for wine producers aiming to enhance perceived quality in their Pinot noir wines.

Effect of Barrel-to-Barrel Variation on Color and Phenolic Composition of a Red Wine

Tangible variation of sensory characteristics is often observed in wine aged in similar barrels. Barrel-to-barrel variation in barrel-aged wines was investigated in respect of the most important phenolic compounds of oenological interest. A red wine was aged in 49 medium-toasted oak (Quercus petraea) barrels, from four cooperages, for 12 months. The resulting wines were evaluated for chromatic characteristics, anthocyanin-related parameters, total phenols, flavonoids and non-flavonoids phenols, flavanol monomers, and oligomeric and polymeric proanthocyanidins. PCA and ANOVA were applied to investigate the relationships between barrels and to assess cooperage and individual barrel effect. Three cooperages influenced the wine similarly during aging. Anthocyanin-related parameters showed the highest variation, 25–37%, other phenolics varied 3–8.5%, and with two exceptions, chromatic characteristics changed 1.7–3%. The relationship between the number of barrels and the expected variation for each analytical parameter was calculated, as reference for future measurements involving barrel lots, either in wine production or experimental design.

Improving the Phloroglucinolysis Protocol and Characterization of Sagrantino Wines Proanthocyanidins

Proanthocyanidins are key metabolites that explain wine sensorial character (bitterness and astringency) and red wine color changes during aging. Therefore, a fast and accurate method to evaluate the degree of polymerization and the structural composition of the polymeric proanthocyanidins is a crucial analytical tool. Phloroglucinolysis is the most used method for this analysis but, unfortunately, the phloroglucinol adducts of the monomeric flavan-3-ols are not commercially available, making the results less accurate. The aim of this work was the isolation by semi-preparative high performance liquid chromatography (HPLC) of these non-commercial compounds and their use for the development of an accurate UHPLC-MS/MS protocol. The purity of each adduct was established via quantitative 1H-nuclear magnetic resonance (NMR) measurements with 3-trimethylsilyl-propionic-d4 acid sodium salt as the calibration standard. The developed method was applied to evaluate the proanthocyanidins profile of Sagrantino di Montefalco wines in comparison to other well-known tannic wines. Commercial, 6-8 years old Sagrantino wines were demonstrated to be very rich in epicatechin type B procyanidins, to have low galloylation %, and to have a high mean degree of polymerization of the proanthocyanidins with respect to the other analyzed wines.

Wine Polyphenol Content and Its Influence on Wine Quality and Properties: A Review

Wine is one of the most consumed beverages around the world. It is composed of alcohols, sugars, acids, minerals, proteins and other compounds, such as organic acids and volatile and phenolic compounds (also called polyphenols). Polyphenols have been shown to be highly related to both (i) wine quality (color, flavor, and taste) and (ii) health-promoting properties (antioxidant and cardioprotective among others). Polyphenols can be grouped into two big families: (i) Flavonoids, including anthocyanidins, flavonols, flavanols, hydrolysable and condensed tannins, flavanones, flavones and chalcones; and (ii) Non-flavonoids, including hydroxycinnamic acids, hydroxybenzoic acids, stilbenes, tyrosol and hydroxytyrosol. Each group affects in some way the different properties of wine to a greater or a lesser extent. For that reason, the phenolic composition can be managed to obtain singular wines with specific, desirable characteristics. The current review presents a summary of the ways in which the phenolic composition of wine can be modulated, including (a) invariable factors such as variety, field management or climatic conditions; (b) pre-fermentative strategies such as maceration, thermovinification and pulsed electric field; (c) fermentative strategies such as the use of different yeasts and bacteria; and (d) post-fermentative strategies such as maceration, fining agents and aging. Finally, the different extraction methods and analytical techniques used for polyphenol detection and quantification have been also reviewed.

Interactions between Polyphenols and Volatile Compounds in Wine: A Literature Review on Physicochemical and Sensory Insights

Wine polyphenols (PPhs) and volatile organic compounds (VOCs) are responsible for two of the main sensory characteristics in defining the complexity and quality of red wines: astringency and aroma. Wine VOCs’ volatility and solubility are strongly influenced by the matrix composition, including the interactions with PPhs. To date, these interactions have not been deeply studied, although the topic is of great interest in oenology. This article reviews the available knowledge on the main physicochemical and sensory effects of polyphenols on the release and perception of wine aromas in orthonasal and retronasal conditions. It describes the molecular insights and the phenomena that can modify VOCs behavior, according to the different chemical classes. It introduces the possible impact of saliva on aroma release and perception through the modulation of polyphenols–aroma compounds interactions. Limitations and possible gaps to overcome are presented together with updated approaches used to investigate those interactions and their effects, as well as future perspectives on the subject.

Phenolic Compounds as Markers of Wine Quality and Authenticity

Targeted and untargeted determinations are being currently applied to different classes of natural phenolics to develop an integrated approach aimed at ensuring compliance to regulatory prescriptions related to specific quality parameters of wine production. The regulations are particularly severe for wine and include various aspects of the viticulture practices and winemaking techniques. Nevertheless, the use of phenolic profiles for quality control is still fragmented and incomplete, even if they are a promising tool for quality evaluation. Only a few methods have been already validated and widely applied, and an integrated approach is in fact still missing because of the complex dependence of the chemical profile of wine on many viticultural and enological factors, which have not been clarified yet. For example, there is a lack of studies about the phenolic composition in relation to the wine authenticity of white and especially rosé wines. This review is a bibliographic account on the approaches based on phenolic species that have been developed for the evaluation of wine quality and frauds, from the grape varieties (of V. vinifera and non vinifera), to the geographical origin, the vintage year, the winemaking process, and wine aging. Future perspectives on the role of phenolic compounds in different wine quality aspects, which should be still exploited, are also outlined.

Liquid Chromatography-Mass Spectrometry-Based Metabolomics for Understanding the Compositional Changes Induced by Oxidative or Anoxic Storage of Red Wines

The aim of this work was to study the physicochemical changes of eight red wines stored under conditions differing in O₂ exposure and temperature and time under anoxia. The methods used to analyze the wines included the measurement of volatile sulfur compounds, color, tannin (T) polymerization, and liquid chromatography-mass spectrometry untargeted metabolomic fingerprint. After 3 months, the color of the oxidized samples evolved 4-5 times more intensively than in wines stored under anoxia. The major metabolomic differences between oxidative and anoxic conditions were linked to reactions of acetaldehyde (favored in oxidative) and SO₂ (favored in anoxia). In the presence of oxygen, the C-4 carbocation of flavanols delivered ethyl-linked tannin-anthocyanin (T-A) and tannin-tannin (T-T) adducts, pyranoanthocyanins, and sulfonated indoles, while under reduction, the C-4 carbocation delivered direct linked T-A adducts, rearranged T-T adducts, and sulfonated tannins. Some of these last reactions could be related to the accumulation of reduced species, eventually ending with reductive off-odors.

Wine or Beer? Comparison, Changes and Improvement of Polyphenolic Compounds during Technological Phases

Wine and beer are nowadays the most popular alcoholic beverages, and the benefits of their moderate consumption have been extensively supported by the scientific community. The main source of wine and beer's antioxidant behavior are the phenolic substances. Phenolic compounds in wine and beer also influence final product quality, in terms of color, flavor, fragrance, stability, and clarity. Change in the quantity and quality of phenolic compounds in wine and beer depends on many parameters, beginning with the used raw material, its place of origin, environmental growing conditions, and on all the applied technological processes and the storage of the final product. This review represents current knowledge of phenolic compounds, comparing qualitative and quantitative profiles in wine and beer, changes of these compounds through all phases of wine and beer production are discussed, as well as the possibilities for increasing their content. Analytical methods and their importance for phenolic compound determination have also been pointed out. The observed data showed wine as the beverage with a more potent biological activity, due to a higher content of phenolic compounds. However, both of them contain, partly similar and different, phenolic compounds, and recommendations have to consider the drinking pattern, consumed quantity, and individual preferences. Furthermore, novel technologies have been developing rapidly in order to improve the polyphenolic content and antioxidant activity of these two beverages, particularly in the brewing industry.

Effect of enological treatments on phenolic and sensory characteristics of red wine during aging: Micro-oxygenation, sulfur dioxide, iron with copper and gelatin fining

This work aimed to study long-term impact of micro-oxygenation and/or different aging treatments: (i) high SO₂, (ii) high Fe with Cu and (iii) gelatin fining on Plavac mali red wine phenolic and in-mouthfeel sensory development in barrels and furthermore in bottles. Results showed that outcomes of micro-oxygenation strongly depend on aging treatments. High SO₂ concentration during aging in barrels and bottles delayed typical phenolic changes and slightly contributed to astringency and lower color intensity, particularly in wine that was not micro-oxygenated. High metal concentrations and gelatin fining promoted intensive polymerization of proanthocyanins and a lower percentage of prodelphinidins after long-term aging in barrels. Also, flavan-3-ol and anthocyanins transformation rates in micro-oxygenated wines of both treatments significantly differed from their controls. Gelatin fining proved to be a very effective treatment for astringency reduction, particularly when combined with micro-oxygenation, but fined wines after long term aging in bottles showed lower color intensity.

Current Research Related to Wine Sensory Perception Since 2010

Due to socioeconomic changes, the demand for and interest in alcoholic beverages have recently been increasing. Among various alcoholic drinks, consumer preference for wine could be varied. It might be related with its complexity, as wine is known to have characteristics that are difficult to understand. Several factors, such as intrinsic or extrinsic factors interact to influence wine complexity and consumer perception. Many studies have been conducted to understand the complexity of wine, allowing deeper insight into its perception by consumers. Studies over the last decade on wine sensory perception using descriptive analysis and consumer tests were reviewed. Additionally, chemical analysis studies were included because flavor constituents information would contribute to a better understanding of sensory perception. Descriptive sensory analysis of wine was reviewed considering panels and flavor characterization for better understanding wine-related research. Several consumer studies regarding liking/preference, emotion, context, and extrinsic factors to understand consumer preference or perception were reviewed. Research on chemical constituents may affect consumer perception and is thus presented in this review. However, most of the research was focused on a narrow range of wine, thus is missing overall wine category evaluations. Furthermore, evaluations were mainly in wine-producing countries, resulting in limited understanding of an emergent market. This review will help guide wine researchers and industry by providing information on factors influencing consumer wine perception.

Masking the Perceived Astringency of Proanthocyanidins in Beverages Using Oxidized Starch Hydrogel Microencapsulation

Proanthocyanidins (PAs) are responsible for several health benefits of many fruits, but they could cause a generally disliked sensation of astringency. Traditional deastringency methods remove bioactive ingredients, resulting in the loss of valuable nutrients and associated health benefits. This work aimed to microencapsulate PAs from grape seeds using oxidized starch hydrogel (OSH) and mask its perceived astringency in beverages while maintaining its bioavailability. The maximum PA uptake capabilities of OSH, as well as the binding site and primary binding force between these two components, were determined. The resulting PA-OSH complex was stable under in vitro digestion, with only 1.6% of PA being released in the salivary digestion, and it has an intestine-specific release property. The reaction of PA with α-amylase in artificial saliva was substantially reduced by OSH microencapsulation, leading to 41.5% less precipitation of the salivary proteins. The sensory evaluation results showed that the microencapsulation was able to mask the astringency of PA-fortified water, as the perceived threshold of astringency increased by 3.85 times. These results proved that OSH could be used as a novel food additive to reduce the astringency of beverage products due to its hydrogel properties and ability to encapsulate phenolic compounds.

Effect of extraction time on content, composition and sensory perception of proanthocyanidins in wine-like medium and during industrial fermentation of Cabernet Sauvignon

BACKGROUND

The research objectives focused on the extraction of grape tannins during extended maceration. Skins and seeds were extracted separately in a wine-like medium. In parallel, the same grapes were fermented in industrial tanks. The content and structural characteristics of extractable proanthocyanidins (PAs) were determined spectrophotometrically and using UHPLC-DAD-MS/MS, respectively. Skin, seed extracts and fermented wines were characterized in chemical and sensorial terms after different extraction durations.

RESULTS

The extraction of high molecular-weight PAs (HMWPs) from seeds increased for up to 20 days, whereas low molecular-weight PAs (LMWPs) reached a plateau earlier. The extraction of HMWPs and LMWPs from skins reached a maximum at the first sampling. Sensory evaluation confirmed greater astringency and bitterness of seed extracts with increasing time. Neither seed nor skin extracts differed statistically in terms of the mean degree of polymerization (mDP) and percentage of galloylation (%G) on different extraction days (except for seeds at the first sampling). During industrial maceration, HMWPs and LMWPs increased up to 12.7% alcohol (9 days of maceration); thereafter, the increase was not significant, whereas the mDP, %G and percentage of prodelphinidins did not significantly change after 11.4% alcohol. There were positive correlations with the wine astringency and PA content.

CONCLUSION

Looking at both simulated and industrial maceration, it can be concluded that, with a longer maceration time, the increase in HMWP content was more evident than PA structural changes. The increasing content of tannins from seeds played an important role in the greater astringency and bitterness of Cabernet Sauvignon macerated at length. © 2019 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Disease Resistant Bouquet Vine Varieties: Assessment of the Phenolic, Aromatic, and Sensory Potential of Their Wines

The search for grape varieties resistant to diseases and to climatic changes notably concerns the wine industry. Nine monovarietal wines from new red grape varieties resistant to cryptogamic diseases (downy and powdery mildews) were evaluated in terms of their total phenolic, anthocyanin and proanthocyanidin contents, anthocyanin profile, volatile composition, and sensory attributes. Thus, the question remains, will these hybrid grapes (≥97.5% of Vitis vinifera genome) lead to wines with organoleptic properties similar to those of Vitis vinifera wines that consumers are used to? Total phenolic (1547–3418 mg GA/L), anthocyanin (186–561 mg malvidin/L), and proanthocyanidin (1.4–4.5 g tannins/L) contents were in broad agreement with those previously described in the literature for monovarietal wines produced with well-known red grape varieties (Cabernet Sauvignon, Merlot, Syrah). With regard to fruity aroma, ethyl esters of straight-chain fatty acids (530–929 μg/L) stood out clearly as the major volatile components for all hybrid wines considered. Sensory analysis revealed significant differences (p < 0.05) for visual aspect, aroma, flavor, global balance, astringency, and body. Overall, these new hybrid grape varieties are not only resistant to cryptogamic diseases, but also present enough potential to become quality wines, since their phenolic and volatile attributes are close to those of common red monovarietal wines.

Red Wine Consumption and Cardiovascular Health

Wine is a popular alcoholic beverage that has been consumed for hundreds of years. Benefits from moderate alcohol consumption have been widely supported by the scientific literature and, in this line, red wine intake has been related to a lesser risk for coronary heart disease (CHD). Experimental studies and meta-analyses have mainly attributed this outcome to the presence in red wine of a great variety of polyphenolic compounds such as resveratrol, catechin, epicatechin, quercetin, and anthocyanin. Resveratrol is considered the most effective wine compound with respect to the prevention of CHD because of its antioxidant properties. The mechanisms responsible for its putative cardioprotective effects would include changes in lipid profiles, reduction of insulin resistance, and decrease in oxidative stress  of low-density lipoprotein cholesterol (LDL-C). The aim of this review is to summarize the accumulated evidence correlating moderate red wine consumption with prevention of CHD by focusing on the different mechanisms underlying this relationship. Furthermore, the chemistry of wine as well as chemical factors that influence the composition of the bioactive components of red wine are also discussed.

Effects of different oenological techniques on the elaboration of adequate base wines for red sparkling wine production: phenolic composition, sensory properties and foam parameters

BACKGROUND

In red sparkling winemaking it is essential to obtain base wines with moderate alcohol content, adequate mouthfeel and color intensity. The aim of this work was to study oenological techniques to obtain adequate base wines for production of red sparkling wine by traditional methods: pre-fermentative cold maceration with dry ice and délestage with premature grapes; and sugar reduction in must and partial dealcoholisation of wine with mature grapes. The effect on oenological parameters, e.g. phenolic content, foam and sensory characteristics, was studied in sparkling wines aged on the lees in bottles for 9 months followed by aging for12 months in bottles after disgorging.

RESULTS

Pre-fermentative cold maceration was the only treatment that increased the content of anthocyanins in sparkling wines at both stages of aging. Sparkling wines elaborated using délestage showed the highest mean values of the degree of polymerization of proanthocyanidins. Sparkling wines from mature grapes were given higher valuation in the gustatory phase. Sparkling wines elaborated using pre-fermentative cold maceration were given the highest valuation for foam quality.

CONCLUSIONS

Pre-fermentative cold maceration is a viable alternative to common techniques for increasing the anthocyanin content in wines from premature grapes. It would therefore be a good option to obtain adequate base wines. © 2019 Society of Chemical Industry.

Proanthocyanidin content as an astringency estimation tool and maturation index in red and white winemaking technology

Selecting the appropriate type of barrel for wine maturation but also deciding on the optimum maturation length, is a challenge for winemakers. As different types of barrel woods emerge, it is of great importance for a guideline to be established, which could facilitate winemaking decisions. Since the sensory perception of the finished wine, and particularly the intensity of astringency, is a decisive factor for the quality of a barrel-aged wine, in this experiment, the structural characteristics of wine proanthocyanidins were determined and their correlation with astringency was established. According to the results obtained, the proanthocyanidin content and the type of subunit that is dominant in tannin chains could be used to construct an astringency estimation model. The findings could provide winemakers with a useful tool when deciding how long to mature a specific type of wine in a specific wood container without making it appear coarse and astringent.

Rapid Quantitation of 12 Volatile Aldehyde Compounds in Wine by LC-QQQ-MS: A Combined Measure of Free and Hydrogen-Sulfite-Bound Forms

This work outlines a rapid novel methodology for the direct quantitation of 12 volatile aldehyde compounds related to oxidative off-flavors in wine, by measuring the combined free and hydrogen-sulfite-bound forms of each aldehyde compound, consisting of four general aldehydes, four Strecker aldehydes, and four (E)-2-alkenals. The methodology requires minimal preparation of wine samples: the addition of internal standards and 6 g/L sulfur dioxide, and filtration prior to quantitation by liquid chromatography-triple quadrupole-mass spectrometery. Overall, the limit of detection, limit of quantification, accuracy (recovery, 97-114%), and precision (repeatability and reproducibility, RSD ≤ 10%) were satisfactory to enable routine measurement of the 12 aldehyde compounds in wine. The methodology was applied to 20 commercial white and red wines from various varieties and vintages. A general trend of higher concentrations of the aldehyde compounds in white wines compared to red wines was observed.

Climate effects on physicochemical composition of Syrah grapes at low and high altitude sites from tropical grown regions of Brazil

The major areas of the world where viticulture is practiced enjoy temperate or cool temperature climates. When wine grapes are grown in tropical regions, edaphoclimatic factors result in distinct grape quality attributes, and production techniques also require significant adjustment. The objective of this study was to characterize the chemical compositions, in particular of phenolic compounds, of Syrah grapes grown in two location in northeast Brazil - these are also at widely different altitudes. A range of methods of phenolic extraction were used, along with classical chemical analyses including for organic acids, sugars, monomeric anthocyanins, flavonols, stilbene, condensed tannins and some of the monomeric and small oligomeric procyanidins. The regions and their diverse environments had a larger influence than harvest year. The grapes at higher altitude (Bahia, 1.100 m asl (metres above sea level) were characterized by higher levels of malic acid, anthocyanins and condensed tannins in the skins. The low-altitude grapes (Pernambuco, 350 m asl (metres above sea level) had higher levels of glucose, fructose, 3-O-acetylglucoside anthocyanins and condensed tannins in the seeds. Fruit composition was highly influenced by the region. In the low-altitude region, the grapes were characterized by higher tartaric and citric acid in the must, also of flavonols in skins and of tannins in the seeds. Meanwhile, the fruit from the high altitude, contained higher levels of malic and succinic acid in the must, and of anthocyanins and condensed tannins in the skins.

Comparison between sensory evaluation and SPME GC-MS in Brazilian's sparkling wines

Looking for understand which is the profile aromatic's complexity in Brazilian's sparkling wines, this study's objective was to evaluate 5 samples of commercial sparkling wines by sensory analysis, and also by a gas chromatography (GC), and mass spectrometry (MS). At the sensory analysis, in Brazil's panel, from a total of 5 sparkling samples, were made 155 determinations of aromas found at wines, with 31 distinct descriptors. The same process was realized at the Italian's panel, and at this time we found 188 determinations of aromas from all the 5 sparkling's samples, with 31 distinct descriptors. For the volatile compounds analysis the gas chromatography-mass spectrometry (GC-MS) identified 26 compounds, the most of them have a fruity characteristic. This study demonstrated the Brazilian's sparkling wines have a profile fruity and floral, with maturation notes.

Chemical and sensorial investigation of in-mouth sensory properties of grape anthocyanins

Anthocyanins are water-soluble pigments found in the cell vacuoles of fruits and flowers, performing several roles from insects attraction to stress protection. Their antioxidant activity contributes to human health, and consuming plant-derived products provides their higher source in the diet. Although their colour and nutritional features, their contribution to sensory properties of foods has not been widely investigated. In wine, preferences are connected with sensory attributes of colour, aroma, taste, and mouthfeel. In this study, grape anthocyanin extracts (TAE) were fractionated using centrifugal partition chromatography (CPC) and preparative HPLC in three fractions, i.e glucoside (GF), acetylated (AF) and cinnamoylated (CF) anthocyanins. Sensory properties were investigated by chemical analysis, as reactivity towards bovin serum albumin (BSA) and salivary proteins, and in tasting sessions to assess anthocyanins best estimated thresholds (BET) in wine-like solution. Anthocyanins reacted with both BSA and salivary proteins, but to different extents, because higher interaction between salivary proteins and anthocyanins were found. Cinnamoylated anthocyanins are the most reactive to salivary proteins. Tasting sessions suggested an involvement of anthocyanins as in-mouth contributors in wine, since their BETs were 255, 297, 68, and 58 mg/L for TAE, GF, AF, and CF, respectively, and the descriptors reported were astringency and bitterness.

Aging of Malbec wines from Mendoza and California: Evolution of phenolic and elemental composition

This work aimed to investigate the evolution of phenolic compounds and elements during the aging of Malbec red wines from different regions of Mendoza (Argentina) and California (United States). The profiles of low molecular weight polyphenols and anthocyanins were analyzed using high-performance liquid chromatography with a diode-array detector (HPLC-DAD), and the elemental composition using microwave plasma-Atomic emission spectrometry (MP-AES). Through uni- and multivariate statistical analyses, the effects of aging time and region on wine were investigated. It was observed that aging time was a significant factor that affected the phenolic compound profile in the studied Malbec wines studied and that after five years of aging, the wines could be differentiated according to region. The results of this study may impact decisions made regarding the storage of Malbec wines in the future.

Sauvignon wine quality as affected by its processing and storage

The colour and limpidity are the first sensory attributes of wines that are appreciated by consumers, predisposing their acceptance or rejection. The aim of this work was to monitor the effect of harvest, processing (different clarification and treatment of must) and storage on the quality of Sauvignon wine. The wines were stored for two years in the wine cellar at 12°C and 70 % of humidity, in the bottles. The acid content, residual sugar and alcohol content among chemical parameters and sensory profile of wines were observed. Sensory quality of wines was evaluated by the aromatic profile (profile method). Based on acquired results, two years of wine storage significantly affected the total acid content of wines and alcohol content. Different treatments of must affected residual sugars, the variant with the maximum dose of the clarification preparation (highly pure cellulose, polyvinylpolypyrrolidone, gelatin and mineral adsorbents) showed statistically the highest content of residual sugars. From the sensory point of view, sensory profiles of wines were different compared to the first and second harvest of grape, sensory profiles of wines were changed also after two years of storage. The fourth variant appeared to be the best stable, treated with the addition of clarification preparation at the dose of 30 g. 100 L-1 must. Because from the same variety Sauvignon were produced wines of different chemical and sensory qualities, some gastronomy recommendations were done as well.

Double maturation raisonnée: the impact of on-vine berry dehydration on the berry and wine composition of Merlot (Vitis vinifera L.)

BACKGROUND

Double maturation raisonnée (DMR) is a potential canopy measure that affects grape and wine composition. The aim of this work was to study for the first time the DMR impact on the physical, biochemical and sensorial characteristics of the berries and wines of Merlot, one of the world's fastest-expanding grapevine varieties.

RESULTS

DMR significantly increased the content of soluble solids (1.2-fold), free amino nitrogen (1.8-fold) and acidity in berries but decreased the weight of 100 berries on harvest (approx. 28%). Irrespective of the vintage, DMR-treated grapes had a significantly higher content of non-astringent tannins (0.73-0.78 mg L^-1 ) and anthocyanin extractability (34.7-36.4%) but a lower index of astringency (31.2-33.7) when compared to the control. Consequently, the DMR wines achieved higher alcohol, total acidity and extract, hydroxycinnamic acids, flavanol and flavonol contents, whereas the content of anthocyanins was similar to that of the control. Sensorial evaluation showed that DMR wines were not rated higher and would not be appreciated more than control wines.

CONCLUSION

Changes in berries during DMR altered the wine characteristics only in terms of primary metabolites. A reduced accumulation of phenolics, especially anthocyanin content, in the berry skin of DMR-treated grapes was not reflected in their presence in wines. To the best of our knowledge, this is the first paper that has reported an impact of DMR on the grape and wine composition of Merlot, as one of the most promising red varieties. © 2017 Society of Chemical Industry.

Changes in Tannin Composition of Syrah Grape Skins and Seeds during Fruit Ripening under Contrasting Water Conditions

Tannin accumulation and composition were determined in skins and seeds isolated from Vitis vinifera cv. Syrah grapes submitted to contrasting water regimes under semiarid climatic conditions. Three irrigation treatments were conducted, starting at berry set through harvest of two growing seasons, 2011 and 2012: irrigation at 100% of crop evapotranspiration ETc (FI), irrigation at 50% of ETc (DI) and non-irrigated (NI). Seed total tannins did not vary with maturity but those of skins underwent a progressive decline (especially in 2011), expressed both on a fresh weight and on a per berry basis. Skin total tannin concentration and content per berry were increased under NI and DI conditions, mainly in 2012. In contrast, seed total tannins (in 2012) and flavan-3-ol monomers and tannin oligomers (both years) were higher in the fully irrigated vines (FI). Skin polymer size increased during ripening, NI and DI skins showing higher mean degree of polymerization (mDP) compared to FI at harvest. NI was also associated with a lower percentage of galloylation (%G) in skin oligomeric fraction (in 2012) and a lower percentage of prodelphinidins in the skin polymeric fraction (both years) at harvest. The mDP and %G of seed extracts did not vary during ripening and were higher in NI but only in 2012. According to the results, management of vine water status was shown to influence tannin amount and composition of Syrah grapes grown under semiarid conditions.

Comparison of Aquitaine and Rioja Red Wines: Characterization of Their Phenolic Composition and Evolution from 2000 to 2013

Wine chemical analysis was carried out on 194 commercial blended red wines produced by two major wine-growing areas—the Aquitaine (France) and Rioja (Spain) regions—in order to compare the wines of both regions. Anthocyanins and derived pigments, tannins and derivatives were identified and quantified by HPLC-DAD-ESI-MS/MS (high pressure liquid chromatography coupled to diode array detector and mass spectrometry using the electrospray ionization interface). Mean degree of polymerization (mDP) was determined. The influence of the wine-growing region and the predominance of the properties of some grape varieties used are confirmed by the significant differences observed between both regions. Rioja and Bordeaux “generic” (Bordeaux and Bordeaux-Supérieur appellations) red wines showed the highest anthocyanic content and the highest mDP, as these wines are in a majority made from Merlot (Bordeaux “generic”) and Tempranillo (Rioja). On the contrary, Bordeaux “specific” regions (Blayais, Médoc, Graves, and Libournais) showed the red wines with the highest total phenolic content and tannin concentration, as the predominant grape variety used is Cabernet Sauvignon. A principal component analysis (PCA) and a hierarchical ascendant classification (HAC) suggesting patterns between the chemical parameters and the distribution of the red wines in three groups were proposed. The comparison of the two wine-growing areas also reveals some similarities between the various grape varieties used. A general effect of a progressive decrease in anthocyanins, anthocyanin-derived pigment and tannins is observed for older wines.

Understanding the Relationship between Red Wine Matrix, Tannin Activity, and Sensory Properties

One major red wine mouthfeel characteristic, astringency, is derived from grape-extracted tannins and is considered to be a result of interaction with salivary proteins and the oral mucosa. To improve our understanding of the role that the enthalpy of interaction of tannin with a hydrophobic surface (tannin activity) has in astringency perception, a chromatographic method was used to determine the tannin concentration and activity of 34 Cabernet Sauvignon wines, as well as sensory analysis done on 13 of those wines. In addition, astringency-relevant matrix parameters (pH, titratable acidity, ethanol, glucose, and fructose) were measured across all wines. Tannin activity was not significantly correlated with any matrix variables, and the perception of drying and grippy was not correlated with tannin concentration and activity. However, ethanol content was well related to mouthfeel attributes and appeared to drive perceived drying. Although fructose and glucose content were well correlated, they did not drive the perception of sweetness, which is explained by the well-known mixture suppression effect.