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Flavonoid biosynthesis in grape ( Vitis spp.) berry skin is affected by environmental factors such as light andtemperature. However, the components of the light signaling and low-temperature-induced abscisic acid(ABA) signaling networks related to flavonoid accumulation in grape berry skin have not been fullyelucidated, and how environmental conditions affect these components remains unclear. To clarify the detailsof the possible light- and ABA-related signal transduction networks, we developed a grape oligo-DNAmicroarray (38,549 independent probes) using the publicly available genomic sequence of grape, andperformed comprehensive transcriptome analysis using detached ‘Pione’ grape (Vitis labruscana × V. vinifera)berries cultured under different light and temperature conditions. Using the microarray data, we explored thelight-inducible and low-temperature-inducible genes in post-veraison grape berries. We identified 40 light-inducible genes, 55 low-temperature-inducible genes, and 34 genes induced by light plus low temperature.Among these, we selected elongated hypocotyl 5 (HY5), open stomata 1 (OST1 ), and enhanced response to ABA 1(ERA1) as candidate light-inducible, low-temperature-inducible, and light- plus low-temperature-induciblegenes, respectively. We investigated their detailed expression characteristics in grape accessions by means ofquantitative real-time polymerase chain reaction analyses, and hypothesized that HY5, OST1 , and ERA1 mightbe involved in flavonoid biosynthesis via light signaling and low-temperature signaling networks. We alsoestablished an extensive catalog of gene expression patterns to support future investigations of other candidategenes that respond to light and temperature in grape berry skin.Key Words: abscisic acid, anthocyanins, environmental factors, flavonoids, transcriptome analysis.IntroductionAnthocyanins and flavonols, which are two classes offlavonoids, are secondary plant metabolites that accu-mulate in various plant organs. The skin color of grape(black, red, or white) is mainly determined by the con-tent and composition of anthocyanins, and flavonolscontribute to wine color through co-pigmentation withanthocyanins ( Baranac et al., 1997 ). Coloration of grapeberry skin is an important determinant of consumerpreference and marketability. However, in regions witha warm climate, decreased grape quality, such as poor

© 2015 by the American Society for Enology and Viticulture. All rights reserved. The effects of preflowering defoliation on the qualitative and quantitative composition of phenolic compounds in the grape skins of Tempranillo grapevines grown in a semiarid terroir of western Spain, Badajoz, were determined. Control vines were compared with defoliation carried out before flowering (ED) in 2009 and 2010. Forty-two phenolic compounds were identified and quantified in the grape skins, including anthocyanins, flavonols, flavanols (cathechin and epi-cathechin and the flavanol dimmers B1, B2, and B3), and hydroxycinnamic acids, as both simple and conjugated molecules. ED did not significantly alter the concentration of total anthocyanidins, although in 2009, 3-O-acylated monoglucosides and p-coumaroylglucoside forms were more abundant in this treatment. A nonsignificant tendency toward increased total flavanols due to defoliation treatment was observed. Leaf removal increased concentrations of flavonols (glycosides of myricetin, quercetin, kaempherol, and isorhamnetin), hydroxycinnamic acids, and stilbenes in season-specific ways. Preflowering leaf removal may contribute to increased concentrations of compounds that can form complexes with anthocyanins (copigments) and may thus improve wine color stability., This research was supported by funds from INIA-FEDER RTA2008-0037 and GOBEX GR10006. D. Moreno is grateful to the Extremadura Government and European Regional Development Fund (ERDF).

The aim of this study was to characterize and compare the wines of main native and nonnative grape varieties grown in Turkey. The polyphenol compositions of red and white monovarietal wines of 11 grape varieties have been evaluated for four vintages (2006-2009). Discrimination of wines with respect to variety and vintage was studied by partial least square-discriminant analysis. Boǧazkere red wines were the highest and Kalecik Karasi{dotless} red wines were the lowest in total phenol content. Syrah wines were the highest in anthocyanin compounds. (+)-catechin and (-)-epicatechin contents of Cabernet Sauvignon, Merlot and Syrah wines were the highest, whereas those compounds were detected in lower amounts in native wines. For the case of white wines, the discrimination among Emir, Muscat and Sultaniye wines was based on hydroxycinnamic acids, flavan-3-ols and total phenol content. The vintage based discrimination of red wines was affected at most from malvidin compounds. White wines could also be discriminated according to their vintage based on the presence of quercetin-3- O-galactoside, vanillic acid and o-coumaric acid. The phenolic descriptors of wines can be used in the authentication of wines with respect to variety and harvest year. © 2014 Elsevier Ltd., Scientific Research Project of Izmir Institute of Technology (2010-IYTE-07)

Loss of Pinot noir wine color and polymeric pigment due to malolactic fermentation (MLF) and potential causes for these losses were studied. Delaying MLF was investigated as a method to minimize loss of color and polymeric pigment. Pinot noir wines were held at 13°C for 0, 14, 28, 100, and 200 days before inoculation with Oenococcus oeni strain Viniflora Oenos to induce MLF. Delaying MLF did not affect loss of color, but delaying MLF for increasing times reduced the loss of polymeric pigment and after 200 days no losses compared to the control were noted. The role of acetaldehyde and/or pyruvic acid degradation by O. oeni during MLF was investigated as a cause for reduced polymeric pigment formation. Wines that had undergone MLF were supplemented with acetaldehyde and/or pyruvic acid to the levels measured in control wines that did not undergo MLF. Wines made with added acetaldehyde had more color and polymeric pigment than MLF wines with no additions, and those made with added pyruvic acid had no change in color or concentration of polymeric pigment. However, addition of acetaldehyde did not completely prevent loss of color after MLF, and color loss due to fining by O. oeni was explored. Wines that did not undergo MLF that were exposed to inactivated O. oeni cells showed no difference in color, polymeric pigment concentration, or monomeric anthocyanin concentration compared to the control wines, suggesting that loss of color during MLF was not due to fining by O. oeni cells.

Xanthylium derivatives are yellow to orange pigments with a glyoxylic acid bridge formed by dimerization of flavanols, which are built by oxidative cleavage of tartaric acid. Although their structure and formation under wine-like conditions are well established, knowledge about their color properties and their occurrence and importance in wine is deficient. Xanthylium cations and their corresponding esters were synthesized in a model wine solution and isolated via high-performance countercurrent chromatography (HPCCC) and solid phase extraction (SPE). A Three-Alternative-Forced-Choice (3-AFC) test was applied to reveal the color perception threshold of the isolated compounds in white wine. Their presence and color impact was assessed in 70 different wines (58 white and 12 rosé wines) by UHPLC-DAD-ESI-MSn and the storage stability in wine was determined. The thresholds in young Riesling wine were 0.57 mg/L (cations), 1.04 mg/L (esters) and 0.67 mg/L (1:1 (w/w) mixture), respectively. The low thresholds suggest a possible impact on white wine color, but concentrations in wines were below the threshold. The stability study showed the degradation of the compounds during storage under several conditions. Despite the low perception threshold, xanthylium derivatives might have no direct impact on white wine color, but might play a role in color formation as intermediate products in polymerization and browning.

Red wines produced in the Xinjiang region of China possess poor color density, and lack fruity notes and elegance. The freeze concentration technique, as a well-established concentration method for liquid food systems, was applied to the Cabernet Sauvignon (Vitis vinifera L.) wine-making process, aiming to investigate its effect on wine quality improvement. Results showed that the freeze concentration treatment did not significantly alter the physicochemical properties of the wine, except for an increase of glycerol and alcoholic content. This technique increased ester contents, as well as decreasing the amount of volatile acids. Higher alcohol contents were also increased, but within an acceptable content range. All taken into consideration, the freeze concentration treated wine showed better fragrance characters according to sensory evaluation. The non-anthocyanin composition was altered by this application, however, the difference disappeared after the aging process. Fortunately, sensory evaluation showed that the treated wine possessed better mouthfeel properties. Anthocyanin contents were enhanced, and effectively stabilized the fresh wine color attributes, resulting in an improvement in appearance of the treated wine. All results considered, it can be concluded that freeze concentration treatment could be a good choice to improve wine quality.

The impact of co-fermenting white grape pomace (WP) and red grape pomace (RP) on the composition of interspecific hybrid wine was studied using the Vitis sp. 'Frontenac' and 'Vidal'. The proanthocyanidin and anthocyanin content of the resulting wines were analysed by HPLC-fluorescence and UPLC-MS/MS, respectively. The CIELAB parameters and volatile compounds were analysed using spectrophotometry-UV and GC-MS-SPME, respectively. The WP addition increased the concentration of monomeric and oligomeric flavan-3-ols, and terpenes in the wines. The manipulation of the WP/RP ratio efficiently modulated the anthocyanin profile of the wines, resulting in faded red colour, a desirable achievement in hybrid red wine, which is usually perceived as too dark. An appropriate ratio (30% RP/6% WP) improved the colour stability of the wines without a significant impact on wine colour. Addition of WP proved to be a suitable tool to modulate the colour, the phenolic and volatile composition of interspecific hybrid wine.

[EN] Phenolic compounds are of crucial importance for red wine color and mouthfeel attributes. A large number of enzymatic and chemical reactions involving phenolic compounds take place during winemaking and aging. Despite the large number of published analytical methods for phenolic analyses, the values obtained may vary considerably. In addition, the existing scientific knowledge needs to be updated, but also critically evaluated and simplified for newcomers and wine industry partners. The most used and widely cited spectrophotometric methods for grape and wine phenolic analysis were identified through a bibliometric search using the Science Citation Index-Expanded (SCIE) database accessed through the Web of Science (WOS) platform from Thompson Reuters. The selection of spectrophotometry was based on its ease of use as a routine analytical technique. On the basis of the number of citations, as well as the advantages and disadvantages reported, the modified Somers assay appears as a multistep, simple, and robust procedure that provides a good estimation of the state of the anthocyanins equilibria. Precipitation methods for total tannin levels have also been identified as preferred protocols for these types of compounds. Good reported correlations between methods (methylcellulose-precipitable vs bovine serum albumin) and between these and perceived red wine. astringency, in combination with the adaptation to high-throughput format, make them suitable for routine analysis. The bovine serum albumin tannin assay also allows for the estimation of the anthocyanins content with the measurement of small and large polymeric pigments. Finally, the measurement of wine color using the CIELab space approach is also suggested as the protocol of choice as it provides good insight into the wine's color properties.

Sauvignon blanc is one of the most important white wine cultivars grown in South Africa. It is well-known that climatic and viticultural factors have a major effect on Sauvignon blanc grape and wine composition and quality. Of equal importance is the effect of production factors on Sauvignon blanc wine composition and quality. The purpose of this study was to evaluate the effect of such factors. Wines were produced from grapes from two regions that were stored overnight at 0°C and 20°C. Skin contact was conducted for 15 hours at these temperatures, with as well as without S02 addition prior to fermentation. Free-run juices were used as control. Settled juices were analysed for 2-methoxy-3-isobutylpyrazine (ibMP) and monoterpenes, and the corresponding wines also for ibMP, acetate and ethyl esters, total polyphenols and total flavanoids. The wines were sensorially evaluated for fruitiness and the typical green pepper/grassy aroma of Sauvignon blanc. Grape temperature, skin contact, and oxidative and reductive conditions prior to fermentation affected some of the above-mentioned component concentrations and therefore wine quality. Generally, most component concentrations were increased by skin contact, while polyphenol and flavanoid concentrations were lower in wines produced oxidatively. It appeared that wines produced reductively from free-run as well as low temperature skin contact juices presented the highest quality.

Wine quality can be significantly affected by tannin and polysaccharide composition, which can in turn be influenced by grape maturity and winemaking practices. This study explored the impact of three commercial wine additives, a maceration enzyme, an enotannin, and a mannoprotein, on the composition and sensory properties of red wine, in particular, in mimicking the mouthfeel associated with wines made from riper grapes. Shiraz grapes were harvested at 24 and 28 °Brix and the former vinified with commercial additives introduced either individually or in combination. Compositional analyses of finished wines included tannin and polysaccharide concentration, composition and size distribution by high-performance liquid chromatography, whereas the sensory profiles of wines were assessed by descriptive analysis. As expected, wines made from riper grapes were naturally higher in tannin and mannoprotein than wines made from grapes harvested earlier. Enzyme addition resulted in a significantly higher concentration and average molecular mass of wine tannin, which increased wine astringency. Conversely, mannoprotein addition reduced tannin concentration and astringency. Addition of enotannin did not meaningfully influence wine composition or sensory properties.

In this paper, the effects of ultrasound irradiation were investigated on the evolution of color properties and major phenolic compounds during wine storage. The results indicate that the changing trends of color parameters are very similar in both the ultrasonically-treated and untreated wines, meanwhile the evolutions of malvidin-3-O-glucoside, monomeric flavan-3-ols and phenolic acids also demonstrate some similar patterns in all wines during storage, respectively. In summary, the ultrasound irradiation does not only temporally influence the color characteristics and phenolic compounds of wine, but also have a longer effect on their evolutions during wine storage. Furthermore, the ultrasonically-treated wine had a quicker changing trend than that of the untreated wine regarding the studied parameters. All these results indicate that the ultrasound might be as a feasible and promising novel technology for wineries to produce more red wines with the similar quality as the traditionally-aged wine in a shorter time.

[EN] Wine colour is one of the main organoleptic characteristics influencing its quality. It is of special interest in red vinifications due to the economic resources that wineries have to invest for the extraction of the phenolic compounds responsible for wine colour, compounds that are mainly located inside the skin cell vacuoles, where the volatile compounds are also found. The transfer of phenolic compounds from grapes to must during vinification is closely related to the type of grapes and the winemaking technique. During traditional winemaking, grapes are crushed and skin macerated for several days, with pumps overs to facilitate the colour extraction. To increase this extraction, some chemical (maceration enzymes) or physical technologies (thermovinification, cryomaceration, flash-expansion) can be applied. In this work, a new methodology has been tested. This methodology consists in the application of high-power ultrasounds to crushed grapes to increase the extraction of phenolic compounds. Crushed grapes were treated with this non-thermal technology and vinified, with 3, 6 and 8days of skin maceration time, and the results were compared with a control vinification, where crushed grapes were not subjected to any treatment and were skin macerated during 8days. The wine chromatic characteristics (determined spectrophotometrically) and the individual phenolic compounds (anthocyanins and tannins, determined by HPLC) were followed during the maceration period, at the end of alcoholic fermentation and after two months in bottle. Also, the wine volatile compounds were determined by GC-MS. The wines made with ultrasound-treated grapes showed differences with the control wine, especially regarding total phenol content and tannin content. The wines elaborated with sonicated grapes and with only three days of skin maceration time presented similar concentration of anthocyanins and twice the concentration of tannins than control wines elaborated with 8days of skin maceration., This work was funded by the SME Instrument of the Horizon 2020 program from the European Commission.

Keeping of red wine in bottles is very important for its maturation and quality. However, there are numerous changes that happen during that period, usually caused by oxidative processes and changes in structure and content of polyphenolic compounds. The goal of this study was to determine the effects of Inactivated dry yeast (IDY) products on aging, phenolics content, colour stability and sensory characteristics of red wine Prokupac (Serbian autochthonous variety). The treatment of wine was done by 3 different IDYP (Lallemand, Canada): Optimum White, Opti Less and Noblesse, applied as 0.2 g/L and 0.4 g /L during 15 days. Subsequently, wine clarification was done, followed by filtration and bottling. Untreated wines were used for comparison. Wine was subjected to accelerated aging (10 days at 55 ° C) and also to normal aging conditions during one year. To determine the influence of IDYP following parameters were monitored: dissolved O2, free and total SO2, sugar free extract, content of total phenolics, flavonoids, flavan-3-ols and anthocyanins, percent of polymeric color, color tint, color intensity and sensory characteristics (Panel method). The obtained results clearly show that IDY products are good scavengers of oxygen and have a positive impact on wine quality preservation and its organoleptic characteristics. However, a slight decrease of polyphenols content was detected.

Wine is one of the oldest known beverages, tracing its antiquity to at least 5000 BC, known to have been prepared by the Assyrians by 3500 BC. It is also mentioned in the Rigveda. It has always been considered as a safe and healthy drink, and a therapeutic agent having medicinal power (antioxidant and antimicrobial activity), enhancer of longevity, and reducer of cardiovascular diseases and of type 2 diabetes. Wines are made from complete or partial alcoholic fermentation of grapes or any other fruit, like apples, plums, peaches, pears, berries, cherries, currants, or apricots. These may be classified broadly according to color as red, rose (pink), or white or can be differentiated as table, sparkling, or fortified wines based on alcohol or carbon dioxide content. The alcohol content of table wine is generally 10–11%, cider and perry 2–8%, and fortified wines or dessert wines 16–23%. Fortified wines are of three types, i.e., sherry, port, and aromatic wines. Fortified wines with additional flavoring are called aromatic wines, for example, vermouth. Sparkling wines are often classified by the method used to achieve their high carbon dioxide content. Compared to the quantity of grape wines produced and consumed in the world, the amount of wine produced from nongrape fruits is insignificant except for cider and perry, which are produced and consumed in significant amounts throughout the world. Plum wines are quite popular in many countries. The production of any wine basically involves fermentation with wine yeast, especially Saccharomyces cerevisiae var. ellipsoideus , although other microorganisms like wild yeast and acetic acid bacteria are also involved either in the production of wine or in the inhibition of fermentation or spoilage of wine during production, maturation, and storage. In general, to produce red wine, the fermentation is conducted on the skin of colored grapes, whereas for white wine the fermentation of skin, pomace, and free juice of white grape varieties is carried out. The fermentation of white grapes is generally conducted at low temperatures of 15–20°C, whereas that of red wine is done at 20–25°C. Sherry is basically a base wine fortified with brandy fermented with flor yeast. In the preparation of sparkling wine, secondary fermentation of base wines is carried out either in bottles or in tanks, whereas fortified wines, like vermouth, make use of spices and herbal extracts. In preparation of cider either natural fermentation or inoculated fermentation is carried out with an optimum level of initial sugar concentration using specific apple varieties so as to produce a low-alcohol beverage. Modern consumption of wine is associated with lower mortality from cardiovascular diseases.

During last years, scientific research on high hydrostatic pressure (HHP) as a nonthermal processing technology for preservation or aging of wine has increased substantially. HHP between 200 and 500 MPa is able to inactivate bacteria and yeasts in red and white wines, suggesting that it may be used for wine preservation. However, these treatments have been shown to promote changes on sensorial and physicochemical characteristics in both red and white wines, not immediately in the first month, but along storage. The changes are observed in wine color, aroma, and taste due mainly to reactions of phenolic compounds, sugars, and proteins. These reactions have been associated with those observed during wine aging, leading to aged-like wine characteristics perceived by sensorial analysis. This chapter will present the influence of HHP technology on wine chemical and sensorial characteristics, criticaly discussing its potentialities and drawbacks. The appropriate use of HHP, based on the scientific knowledge of the reactions occuring in wine promoted by HHP, will allow to exploit this technology for wine production achieving distinct characteristics to address particular market and consumer demands.

The purpose of the paper is to contribute to understanding the role and effectiveness of different quality clues in the creation of value for the main wines of the Lazio region. The study presents a hedonic price model. An ordinary least squares and a quantile regression models were estimated. The latter is able to detect additional patterns related to the effects of the covariates. Prices are regressed on wine color, sub-regional area of origin, the type of certification of origin, and on experts' evaluation. The analysis is based on data released by three major Italian wine guides: Gambero Rosso, l'Espresso, and AIS (Italian Sommelier Association). Results show that: (i) white and red wines follow two different price patterns; (ii) prices are correlated with experts' evaluation; (iii) the impact of the latter is higher when other quality clues, such as geographical indications, are less effective; (iv) the role of different quality clues varies at different price levels and it is different for red and w...

BACKGROUND The Hellenic vineyard embraces a large number of native cultivars, which are mostly unexploited for their ageing potential. Therefore, it was thought that analyzing some quality parameters of 14 red wines produced by rare native varieties would be of great importance in obtaining a general picture of their potential for commercial use. Various analytical methods were applied to the selected wines, at bottling and after 8 years of ageing, in an attempt to provide reliable answers to this issue. In addition, it was of interest to investigate the alteration of the phenolic content and color parameters of the wines after extended bottle storage and to evaluate the overall changes with respect to their sensory properties. RESULTS Most of the oligomeric phenolic compounds identified in the wines studied diminished after 8 years of bottle storage, while significant correlations were obtained between wine chemical composition and sensory data. CONCLUSIONS After 8 years of bottle storage some of the unexploited varieties (Vitis vinifera) were found to be worthy of further study and use for the production of quality wines. Wines with the best sensory characteristics were those made by Limniona, Mavrotragano, Bakouri, Thrapsa and Mavrothiriko, in accordance (more or less) with the results of chemical analyses. © 2014 Society of Chemical Industry

The chemical and sensory effects of storing Sauvignon Blanc in colored bottles and exposing them to artificial light were examined. The colors of the bottles chosen were Dead Leaf Green, Antique Green, Amber, and Flint. The light was provided by fluorescent tubes with a regime of 16 h of exposure during 8 months of storage. The results indicated that the wine's chemical composition was affected by the type of bottle used. The Flint bottle presented the lowest concentration of total phenols. Yellow coloration was not dependent on the bottle color, as the wine in darker bottles (Amber, Antique Green, and Dead Leaf Green) had considerably more yellow color development than the wine in clear bottles. With regard to the sensory analyses performed, a trend showing an increase in color intensity and a decrease in overall aromas depending on the bottle color was observed. The wine's aromatic description changed significantly during its storage under artificial light conditions, demonstrating a decrease in vegetal aromas and an increase in citrus and tropical flavors that was dependent on the bottle color.

A breeding programme by intra-specific crossing was set up in 1989, in the experimental Station ?Riccagioia? (Lombardia region, north-west Italy), with the aim of getting new varieties mainly for white sparkling wine. V. vinifera L. ?Riesling italico? was used as the female parent, while cv. ?Pinot noir? and cv. ?Chardonnay? were used as males, resulting in two progenies (designated RPN and RCH). 900 and 400 seedlings were obtained from RPN and RCH crossings respectively, and a low-pressure field selection was performed, choosing 50 individuals out of the 1,300, by utilizing as screening criteria vegetative habit, phenology, ripening and health aspects. The selected seedlings were grafted on SO4 rootstock, and the productivity and qualitative grape parameters of the field-grown vines were checked over a 4-year-period (2002-2005) by multifactorial analysis of variance (MANOVA) and SNK (Student Newman Keuls). DNA fingerprinting (by microsatellite) of the progenies and the parent varieties was performed as well, confirming the parentage. Grapes were vinified at harvest, and the wines were evaluated according to sensory analysis, by processing the main descriptors by the non parametric Friedman test. According to the above mentioned parameters, three new varieties were selected, as follows: RCH10 and RPN33 (both white berry) and RPN26 (red berry), due to a good canopy (RCH10), high acidity and sugar and very low cluster and berry weight (RPN26). RCH10 and RPN33 are interesting for sparkling wine because of the white color, the wider sensorial profile and the highest pleasure indices, as compared to the parents (cv. ?Riesling italico? and cv. ?Pinot noir?). RPN 26 has an unexpected later ripening and a wine color intensity much higher than ?Pinot noir?, being suitable for the production of red wines; according to the high-pressure selection tightly connected with the objectives of this breeding program, this genotype would have been excluded in the first step of the selection procedure.

The goal of this study was to determine the trans-resveratrol concentration in wine. A set of 70 wine samples from Romania, produced according to the appellation of origin system, were analyzed by reverse-phase high performance liquid chromatography. White wines were found to have markedly lower concentrations of trans-resveratrol in comparison with red wines. The values were between 0.025 to 10.23 mg/L for red wine and from 0.074 to 2.572 mg/L for white wine. Red wine is a good dietary source of resveratrol.

The latest research revealed that phenolic compounds play an important role in the quality of red wine, particularly on colour and astringency and also are responsible for the sanogenic or multiple benefic effects on human health after a moderate consumption of wine. This paper presents the ripening evolution of routine quality control parameters (sugars, acids, weight of 100 berries) and phenolic compounds (anthocyanins and polyphenolic index) during 2013 year for the most representative red grape varieties (Cabernet Sauvignon, Merlot, Feteasca Neagra, Pinot Noir and Mamaia) authorized to obtain wines with denomination of origin controlled in Murfatlar wine center. Also, the phenolic profile of obtained red wines was evaluated by reversedphase high performance liquid chromatography. The reported results were useful to find the optimum moment for grape harvest ensuring the production of high quality wines.

Cross-flow filtration is an increasingly common postfermentation process in the wine industry. Our hypothesis was that cross-flow filtration would not have a significant impact on the sensory or chemical properties of white or red wines because of the nature of the membranes used in this process. To investigate this, a California white wine blend and a California red wine blend were filtered in three 570 L lots using a Bucher Vaslin cross-flow unit with a nominal 0.22-micron polyethersulfone membrane. The unfiltered control was sent directly to the bottling line without filtration. Panelists evaluated the wines nine times during an eight-month descriptive analysis panel with replicated tasting at each time point. UV-vis spectrophotometry and the Adams–Harbertson assay were used to determine color and phenolic content of the filtered and unfiltered wines, respectively. The effect of filtration was significant for one sensory attribute out of 16 total measured in the white wine. Similar analysis indicated that six sensory attributes were significantly different out of 16 total in the red wine. Unfiltered red wines were higher in earthy, grassy, oak, and smoke aromas compared to filtered wines and lower in mixed berry and stone fruit aromas compared to the filtered wines, but only after two months in bottle. Cross-flow filtration was found to have a stabilizing effect on the sensory profile of both wines. For both wines there were significant changes in color and phenolic profile with filtration, but it is not clear, especially for red wines, whether the changes in phenolic compound concentration were great enough to be detected sensorially.

Anthocyanins, responsible for wine colour, are involved in many reactions during wine ageing. Anthocyanin-flavanol associations give rise to derivatives in flavylium form that provide blue hues, but also derivatives that do not directly influence wine colour. These colourless derivatives remain mostly unknown but their roles during wine ageing are important for controlling wine quality. Colourless anthocyanin-flavanol derivatives formed during wine ageing have been studied in three aged red wines from Rioja using a combined method with Column Chromatography (CC) and High Performance Liquid Chromatography with Diode Array and Mass Spectrometric detections (HPLC-DADMS). Twenty-six compounds have been detected: 17 dimers with the anthocyanin in flavene form with possible anthocyanin-flavanol (type 1) and flavanol-anthocyanin (type 2) structures, and 9 with an A-type bicyclic anthocyanin-flavanol structure (type 3). Although some of malvidin derivatives have been previously reported, this is the first time that these derivatives (including different isomers) have also been detected for delphinidin, petunidin and peonidin.

We review the extraction into wine and evolution of major phenolic classes of sensory relevance. We present a historical background to highlight that previously established aspects of phenolic extraction and retention into red wine are still subjects of much research. We argue that management of the maceration length is one of the most determining factors in defining the proportion and chemical fate of phenolic compounds in wine. The extraction of anthocyanins, flavonols, flavan-3-ols, and oligomeric and polymeric proanthocyanidins (PAs) is discussed in the context of their individual extraction patterns but also with regard to their interaction with other wine components. The same approach is followed to present the sensory implications of phenolic and phenolic-derived compounds in wine. Overall, we conclude that the chemical diversity of phenolic compounds in grapes is further enhanced as soon as vacuolar and pulp components are released upon crushing, adding a variety of new sensory dimensions to the already present chemical diversity. Polymeric pigments formed by the covalent reaction of anthocyanin and PAs are good candidates to explain some of the observed sensory changes in the color, taste, and mouthfeel attributes of red wines during maceration and aging.

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.

The composition of the colour components of commercial red wines from Italy was analysed in terms of total colour, co-pigmentation, SO2-resistant pigments, small and large polymeric pigments, and tannins. A total of 128 wines, including Sangiovese, Cabernet Sauvignon, Nero d’Avola, Merlot, Marzemino, Negroamaro, Aglianico, Cannonau and Rossese di dolceacqua from five vintages (1999 to 2003) were analysed. The composition of the wines showed significant differences in terms of total colour and co-pigmentation. Total colour at 520 nm was highest in Marzemino (7.50±1.5 AU, absorbance units), and then in Aglianico (7.10±2.8 AU) and Cabernet Sauvignon (5.01±2.50 AU). The level of large and small polymeric pigments in Sangiovese wines showed a range from 0.05 to 0.40 and 0.10 to 0.27 AU 520 nm respectively. The variation in the level of polymeric pigments is affected by a number of factors, including vintage, grape composition, fermentation and storage conditions.

Phenolic compounds in red grapes might give an indication of phenolic and colour compositions of the resulting wine. This work compared the Glories, Iland and Bovine Serum Albumin (BSA) tannin precipitation methods for phenolic characterization of South African Pinotage, Merlot, Shiraz and Cabernet Sauvignon red grape samples (n=31). Significant positive correlations were found for certain phenolic characteristics in the grapes measured by these methods. Levels of phenolic compounds in the grapes and correlating wines were in line with literature. Merlot samples often associated more with higher concentrations of seed tannins, which were also reflected in the wines. Significant correlations were also found with the colour characteristics of the resulting wines and some anthocyanin related measurements in the grapes with the Glories and Iland methods, with the latter correlating slightly better. Significant positive correlations were also found between grape and wine tannins as measured with the BSA method. However, malolactic fermentation changed some of these correlations and this needs to be investigated further. This work might give wine producers as well as wine analyses laboratories valuable information regarding the suitability of these methods to characterize the phenolic composition of South African red grapes and their resulting wines.

Aliquots of a wine of Merlot were micro-oxygenated at two doses of oxygen (2.5 and 5.0 mg of O2/L.month) in the presence or not of oak staves of different potential ellagitannin release (PER) for three months. In general, micro-oxygenation increased the color intensity and stability probably because favor the formation of new pigments. The presence of staves increased the total phenolic index and the ellagitannin concentration, and this effect was higher when greater was the PER of the staves. Finally, the dose of microoxygenation only affects the concentration of total furanic compounds whereas the PER of the staves seems to determine the concentration of furanic compounds, volatile phenols and β-methyl-γ-octolactones.

Red wines were made from Vitis vinifera cv. Cabernet Sauvignon in China at different methods of maceration. The effects of using different winemaking technologies during maceration on the quality characteristics, in terms of colour, aroma profile and sensory characteristics, of the wines before bottling were evaluated, and made a comparison with the effects of adding skins. Seed contact treatments raised wine colour intensity, proanthocyanidins, tannins, and polyphenols content in comparison to the control wines. However, as indicated in the sensory evolution, the significant increase in astringency intensity was found in the wines with seed contact. Besides, the bitterness of the red wine also increased in the wines with seed contact, but it was not significantly.

The impact of wine pH and closure type on color, tannin concentration, and composition was investigated. A single vintage of Cabernet Sauvignon wine was divided into three batches, the pH was adjusted to 3.2, 3.5 or 3.8, and the wines were bottled under screw caps with either SaranTin (ST) or Saranex (Sx) liners. After 24 months, the tannin concentration, tannin percent yield (relating to the proportion of acid-labile interflavan bonds), and the mean degree of polymerization (mDp) had decreased significantly, all of which can contribute to the softening of wine astringency with aging. The higher pH wines contained less percent (-)-epicatechin 3-O-gallate subunits, whereas the Sx pH 3.2 wines were significantly lower in percent yield and mDp than the other wines. Overall, the tannin structure and wine color of the lower pH wines (pH 3.2) bottled under Sx screw caps changed more rapidly with aging than those of the higher pH wines (pH 3.8) bottled under ST screw caps.

Red wines were made from Vitis vinifera cv. Cabernet Sauvignon in China at different methods of maceration. The effects of adding seeds during maceration on the quality characteristics, in terms of colour, and functional characteristics, of the wines before bottling were evaluated, and made a comparison with the effects of adding skins. Seed contact treatments raised wine colour intensity, anthocyanidins, and tannins in comparison to the control wine.

The application of different elicitors to plants has proved a useful technique for the improvement of their phenolic content. However, studies have shown that the exact response of plants to elicitors depends both on variety and clone. In the present study, two elicitors (benzothiadiazole and methyl jasmonate) were applied in a vineyard where a collection of the six selected clones of Monastrell grape variety were planted to determine whether any observed effect was clone-dependent. The analysis of anthocyanins, flavonols, stilbenes, and seed and skin tannins showed that, in general, both elicitors increased the levels of phenolic compounds in the treated plants, although the extent of the response differed among different clones from the same variety. The positive effect of both benzothiadiazole and methyl jasmonate indicated that such treatments could be regarded as useful for improving grape and wine color while also increasing resistance to some pathogens. However, a preliminary exploratory field study should be carried out since differences in the response of the grapes to treatment might occur, depending on the clone.

Summary Winemakers are interested in wines with low bitterness and astringency, and therefore, there is a preference for a higher presence of skin proanthocyanidins in wines. However, the information regarding the effect of reducing or eliminating seed proanthocyanidins from the must or fermenting wine on the characteristics of finished wines is scarce. For this reason, we elaborated a wine using Monastrell grapes from which the seeds had been removed and compared it with a control wine (CW) made from intact grapes. The anthocyanin and proanthocyanidin concentration and profile, and the chromatic and sensory characteristics were studied. The absence of seed proanthocyanidins did not affect anthocyanin concentration, although the proanthocyanidin concentration was 40% lower than in the CW. The copigmentation (CA) study showed that both wines had a similar extent of CA phenomena although colour intensity was higher when seed proanthocyanidins were present. The panellist evaluated the wines elaborated without seeds as being fruitier, less astringent and with an overall higher quality.

Malolactic fermentation (MLF) is an integral step in red winemaking that results in a decrease in acidity and can also influence additional wine quality parameters. This study examined the impact of MLF on red wine color and the ability of Oenococcus oeni to degrade compounds important to the development of polymeric pigments. Pinot noir and Merlot wines were produced where a portion of the wines underwent a simultaneous alcoholic and malolactic fermentations with O. oeni strain VFO. Post-alcoholic MLFs were conducted using VFO and two additional O. oeni strains in sterile filtered wines. A control wine that did not undergo MLF was pH adjusted to the same pH as wines that had undergone MLF. Wines that underwent MLF (MLF+) contained lower concentrations of acetaldehyde and pyruvic acid than wines that did not undergo MLF (MLF-). Wines that underwent MLF with O. oeni VFO also had higher concentrations of caffeic and trans - p -coumaric acids. MLF+ wines had significantly lower color and polymeric pigment content than MLF-wines and contained significantly higher monomeric anthocyanins. Vitisin B concentrations were also significantly lower in wines that underwent MLF. These differences remained throughout nine months of storage, demonstrating that MLF can affect red wine color independent of pH change. While O. oeni influenced the concentration of phenolic and nonphenolic compounds involved in red wine color development there were no strain specific differences in color and polymeric pigment content.

Red wines were made from Vitis vinifera cv. Cabernet Sauvignon in China at different methods of maceration. The effects of adding seeds during maceration on the quality characteristics, in terms of colour, aroma profile and sensory characteristics, of the wines before bottling were evaluated, and made a comparison with the effects of adding skins. Seed contact treatments raised wine colour intensity, proanthocyanidins, tannins, and polyphenols content in comparison to the control wines. However, as indicated in the sensory evolution, the significant increase in astringency intensity was found in the wines with seed contact. Besides, the bitterness of the red wine also increased in the wines with seed contact, but it was not significantly

Two red wines with a very high ethanol content were partially dealcoholized by reverse osmosis, so that the influence of this technique on wine color, chemical composition and sensory quality could be studied. No statistically significant differences were found in pH, color intensity, total phenolic index, proanthocyanidin concentration and their mean degree of polymerization between control wines and partially dealcoholized wines (−1 and −2 vol. %). Some slight but significant differences were found in titratable acidity, anthocyanins, CIELab coordinates and polysaccharides. However, these differences were really quite small and only significant in a few cases. Moreover, a trained panel of tasters had severe difficulty in distinguishing between control and partially dealcoholized wines in triangular tests, and results were statistically significant only in some of the comparisons. It is concluded that this technique can be very useful for the partial dealcoholization of red wines because they hardly alter their composition and sensory characteristics.

The evolution of the principal families of polyphenols, color intensity, chromatic and organoleptic characteristics was studied throughout the 24 months of aging in bottle under controlled temperature of young red wines elaborated from red grape varieties in danger of extinction in Castilla-La Mancha (Bobal, Moravia Agria and Tortosi) together with the reference red grape cultivar from this Spanish region (Cencibel). With respect to chemical composition, a decrease in the concentration of anthocyanins, flavonols, vitisin-type pyranoanthocyanins, coutaric and caftaric acids and flavan-3-ols was observed. On the other hand, there was an increase in hydroxyphenyl-type pyranoanthocyanins and caffeic and p-coumaric acids. Aging affected to the color intensity following a similar pattern in all wines: a slight decrease during the first 12 months followed by a greater decrease in color intensity to month 24. Sensory descriptive analysis showed that all the wines maintained their initial characteristics until the year of storage. Significant differences regarding the initial organoleptic characteristics of the wines were found after 24 months of storage.

Phenolic extraction in hybrid and interspecific wine grape cultivars is poorly understood, especially in terms of the impact of fermentation and enological conditions on condensed tannins and anthocyanins. Following fractionation via solid-phase extraction and high-performance liquid chromatography, phenolic profiles of must and wine from red hybrid grape cultivars Marechal Foch, Corot noir, and Marquette were examined to assess the impact of enzyme and tannin addition, cold soak, and hot press during vinification. Across cultivars, hot press treatments resulted in the greatest extraction of condensed tannin, anthocyanin, and other monomeric phenolic compounds in musts, and treatments that increased skin contact time or cellular degradation during fermentation produced higher concentrations of tannins, anthocyanins, and flavonols. However, these increases were transient, evincing incomplete carryover into finished wines. Depending on initial must extraction, diglucoside forms of anthocyanins were either selectively extracted or selectively retained throughout fermentation when compared to their monoglucoside counterparts. Typical of hybrid grapes, tannin concentrations across cultivars were low, even under hot press conditions. For condensed tannins and anthocyanins, a cultivar-specific, stable-state concentration and phenolic profile emerged regardless of fermentation conditions. Due to the high levels of diglucoside anthocyanins and low levels of condensed tannins, it is expected that the color development and profile in these wines produced from hybrid grape cultivars will be dictated by the monomeric anthocyanins and their potential role in copigmentation processes involving other monomeric phenolic species, as opposed to the formation of polymeric color pigments.

Ultraviolet–visible irradiation was tested as an innovative technology that can help reducing the amount of sulfur dioxide used in white wine manufacturing. In addition, the effects of must freezing before processing were also investigated. Musts from Xarel·lo and Parellada varieties were vinified without any protective treatment, with a standard amount of SO 2 addition or after an irradiation step. The results showed that UV–vis irradiation of must was able to prevent wine from spoilage in the same degree as SO 2 , without changing other quality parameters such as pH, tartaric acid and alcohol content. However, a residual addition of SO 2 would be required in order to completely inhibit polyphenol oxidase activity. Moreover, the obtained changes in wine color parameters led to the conclusion that further optimization of the irradiation process is required before its implementation. Must freezing was shown to have some influence on quality parameters of Xarel·lo wines, but not in those from Parellada.

[EN] A study of the changes of copigmentation phenomenon in wines elaborated from different varieties has been undertaken. Colorimetric measurement of Tempranillo (T) and Graciano (G) monovarietal wines, and two 80:20 blend wines: M, (grape blending T and G, co-maceration) and W (wine blending T and G, co-vinification) was performed by spectrophotometry. Significant differences (p < 0.05) were found among the color of the wines. The Graciano cv. afforded somewhat darker and more colorful wines than the other wines. The color difference values, ΔE*ab suggested that co-vinification (W) led to wines being more similar to T than the co-maceration (M). The ΔE*ab[w − c] between untreated wines – whole wines, w – and the wines diluted to eliminate copigmentation – corrected wines, c – was 14.2 CIELAB units in the initial stages of winemaking and 6.7 in the final stages. M had a greater proportion of color due to copigmentation than the monovarietal wines. Evaluation of this parameter confirms the importance of copigmentation process into wine color during the early stages of the vinification. Also, through the full spectrum, quantitative data obtained allow a visual interpretation of the changes involved. In addition, with the aging in bottle, M wines had more stable color and more different color than W wines.

Phenolic composition, chromatic characteristics, and antioxidant activity of young wines made from three minority red grape varieties (Moravia Dulce, Rojal and Tortosi) 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 Tortosi 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, Tortosi 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 rose wines. Finally, all wines showed remarkable antioxidant activity, closely connected with their phenolic content. The results suggest that Moravia Dulce and Tortosi grape cultivars could be appropriate raw materials for the elaboration of quality young red wines, whereas Rojal grapes could be for rose wines.