HPLC-DAD–MS/MS characterization of phenolic compounds in white wine stored without added sulfite

The oxidation of dihydroxybenzene and hydroxycinnamate compounds generates unstable quinones which undergo further reactions to combine nucleophilic compounds. These reactions are limited when sulfur dioxide (SO₂) is used as wine preservative, as SO₂ plays an important role in reducing quinones back to their phenol form. In no sulfite-added wine, oxidation chemistry undoubtedly results changed. Therefore, in this work, the phenolic profile of a white wine without adding sulfites, after twelve-month storage, was investigated by HPLC-DAD-MS/MS and compared to a control stored with sulfur dioxide. A total of twenty-six phenolics were detected including hydroxycinnamate derivatives and minor compounds resulting from oxidation processes, i.e. oxidized caffeic acid dimers, whose structures were tentatively proposed on the basis of their UV, MS, and MS/MS typical fragmentation. The experimental evidence of these latter is described for the first time in wine stored without added sulfites, and it may contribute to get new insight in the field of wine oxidation processes.     

Antioxidant activity and phenolic compounds in organic red wine using different winemaking techniques

Abstract: Wine phenolic composition depends on the grapes used to make wine and on vinification conditions. The occurrence of these biological compounds has stimulated numerous studies focused on understanding the mechanisms that influence their concentrations in wine. This article studied the effect of different vinification techniques on the antioxidant activity and on the phenolic compounds of red wine made from the variety of Monastrell grapes obtained by organic culture. To this purpose, 3 different vinification procedures were carried out: vinification after prolonged maceration, vinification with the addition of enological enzymes, and traditional vinification procedures (used as control).The results showed similar values of antioxidant activity in all 3 types of wine elaborated and found no differences in the concentrations of the different types of phenolic compounds in wine made with the 3 different methods. The evolution of antioxidant activity and phenolic compounds tested in wines during 3 mo of storage showed a similar pattern. Organic wine has acquired an important role in the economic world and its important, working in oenology to research in this field.     

The Study of Phenolic Compounds as Natural Antioxidants in Wine

Plant phenolics present in fruit and vegetables, and that are particularly rich in red wine, have received considerable attention because of their potential antioxidant activity. Human consumption of antioxidants has many alleged health benefits, including protection against cardiovascular diseases, and, most recently, cancer. Red wines contain a variety of polyphenolic antioxidants. Five samples of commercial red wines from Spain and four phenolic compounds of red wine: gallic acid, trans-resveratrol, quercetin and rutin, have been studied. The total phenolics content and the total antioxidant activity (TAA) of wines was determined. The total phenolic content, determined according to the Folin-Ciocalteu method, varied from 1800 to 2300?mg/L, expressed as gallic acid equivalents (GAE). The antioxidative effects of wine phenolics were determined using a system based on the inhibition by antioxidants of the absorbance of the radical cation. The relationship between antioxidant activity of phenolic compounds, as hydrogen donating free radical scavengers, and their chemical structures was studied. Furthermore, the total antioxidant activity of the wines investigated was well correlated with phenol content. Thus, the results confirm that red wine polyphenols are, in vitro, significant antioxidants.     

Effect of high pressure treatments on the physicochemical properties of a sulphur dioxide-free red wine

The application of high hydrostatic pressure (HHP) in winemaking for substitution of the use of sulphur dioxide is still at a very early stage of development, since knowledge about the effect on physicochemical and sensorial characteristics of the wine during storage is very scarce. In this work, the evolution of colour, antioxidant activity and total phenolic compounds of SO₂-free red wines treated by HHP and aged in bottles was followed for 12 months. The pressurised wines were compared with wine samples prepared with addition of 40 ppm of SO₂ and without any of these two treatments. After 12 months, the pressurised wines presented higher values of CIELab parameters (a^∗, b^∗, and L^∗) and a lower monomeric anthocyanin content (45–61%) when compared to the unpressurised ones. The pressurised wines showed also a better global sensorial assessment, with the pressure treatments imparting aged-like characteristics to the wines. The wine deposits of pressurised wines had higher total phenolic content, namely proanthocyanidins (3- to 10-fold). The results demonstrate that HHP can influence long term red wine physicochemical and sensorial characteristics, hypothesised to be due to an increase of condensation reactions of phenolic compounds, forming compounds with higher degree of polymerisation that became insoluble in wine along storage.     

Better wine for better health: Fact or fiction?

In the first decade of the twenty‐first century, the potential therapeutic effects of regular moderate wine consumption are being increasingly acknowledged. They include a reduction in the risk of, and death from, cardiovascular disease, which accounted for 40% of all Australian deaths in 2000. The reduction in risk for wine consumers is similar to that of consumers of fruits, grains and vegetables, which, together with wine, are the core components of a ‘Mediterranean‐style diet’. The chemical components of wine considered primarily responsible for this therapeutic effect are ethanol, and the phenolic compounds and their polyphenolic forms. Indeed, moderate wine consumption has been observed to supplement the cardioprotective effects of an already high phenolic diet, and more importantly, to counter the harmful effects of a high fat diet on blood clotting, endothelial function and lipid oxidation, which contribute to the development of cardiovascular disease. This paper explores both the viticultural and vinification factors that influence phenolic concentration in grapes and wine. The synthesis and accumulation of phenolic compounds in grapes is primarily dependent upon varietal factors, the expression of which is influenced by a combination of climatic and viticultural factors such as sunlight and temperature during ripening, as well as ripeness at harvest. While the maximum possible concentration of phenolic compounds in a wine will be determined by the content in the constituent grapes, factors which influence the extraction of the phenolic compounds from the skins and seeds primarily influence their concentration in the juice, must and wine. Once harvested, the concentration of phenolic compounds in grapes is invariate, but extraction efficiency can vary during vinification. Accordingly, this paper also explores innovative techniques and technologies that can increase the phenolic content of the resultant wine. At best, winemaking can only extract at 50% of the total phenolic compounds accumulated in the grapes. Therefore, the phenolic content of the resultant wine can only be increased by supplementation of the must during fermentation with additional sources of phenolic compounds. Alternatively, a grape seed extract could be added to wine post fermentation to supplement its phenolic content, although this same grape seed extract may also be added to other foods such as yoghurt, from which the phenolic compounds are readily absorbed. Regular and moderate consumption of wine by consumers should, however, be placed in context with the other constituents and characteristics of a healthy diet and lifestyle. Indeed, wine consumers generally have fewer risk factors for cardiovascular disease compared with beer and spirits consumers, which is reflected in an approximately 25% to 35% lower risk of cardiovascular disease for wine consumers compared to consumers of beer and spirits, respectively.     

葡萄酒中的酚类物质I：种类、结构及其检测方法研究进展

葡萄酒以其复杂的风味受到广大消费者的青睐。酚类物质是葡萄酒中重要的组成部分,影响其感官品质。同时酚类物质也被认为是葡萄酒保健功能的来源。葡萄酒中的酚类物质复杂多样,主要包括了类黄酮类物质和非类黄酮类物质,其中类黄酮类物质包括花色苷及其衍生物、黄烷醇类和黄酮醇类。非类黄酮类物质包括羟基苯甲酸、羟基肉桂酸和芪类物质。本文对上述葡萄酒中的酚类物质进行了系统综述,包括其种类、结构与性质,同时对这些物质的主要检测方法以及研究进展进行了总结,以期为相关研究者提供学术参考,为葡萄酒行业从业者提供一定的指导。     

Evolution of the phenolic content of red wines from Vitis vinifera L. during ageing in bottle

The evolution of the phenolic content, as measured by spectrophotometric methodologies [total polyphenols (TP), low-polymerized polyphenols (LPP), total anthocyanins (TA), catechins (CAT), proanthocyanidins (PRO) and o-diphenols (OD)], was studied in young red wines from Vitis vinifera L. cv Tempranillo, Graciano and Cabernet Sauvignon during 26 months of ageing in bottle. Although the wines showed differences in their initial phenolic profiles, the evolution trend of the different families of phenolic compounds was similar in the wines from the three grape varieties. TA markedly decreased during ageing in bottle (43% for Tempranillo, 65% for Graciano and 66% for Cabernet Sauvignon), following a first-order kinetic. Calculation of the kinetic parameters revealed that the disappearance rate of TA was 2-fold lower for Tempranillo wine than for Graciano and Cabernet Sauvignon wines, which exhibited similar kinetics. This decrease in TA (due to the disappearance of monomeric anthocyanins), together with a increase registered in CAT and PRO (due to the cleavage of proanthocyanidins and their structural tranformations), was consistent with a decrease in LPP, suggesting the occurrence of condensation reactions during ageing in bottle. The evolution trends observed for TP and OD during ageing in bottle were the results of changes in the different groups of phenolic compounds involved in both determinations. Global phenolic determinations, usually performed in wineries, provided useful information in relation to the evolution of wine polyphenols during ageing in bottle.     

刺葡萄酒发酵过程中几类多酚成分的含量变化分析

该文以两种湖南刺葡萄品种（米葡萄和甜葡萄）为原料酿造的干红葡萄酒为研究对象,并利用高效液相色谱-质谱联用（HPLC-MS）技术分析在其酿造过程中酚类物质的含量变化。结果显示,在刺葡萄干红葡萄酒样品中共检测到六大类酚类物质共33种,其中包括7种黄酮醇类物质、5种黄烷-3-醇类物质、3种羟基苯甲酸类物质、3种羟基肉桂酸类物质、7种非酰化花色苷类物质、8种酰化花色苷类物质。在整个酿造过程中,两种刺葡萄酚类物质的变化基本一致,苹乳发酵结束后酚类物质均明显上升。其中米葡萄酒的黄酮醇、黄烷醇含量高于甜葡萄酒,而甜葡萄酒的其他四种酚类物质含量比米葡萄酒高。     

Interactions of phenolic and volatile compounds with yeast lees,commercial yeast derivatives and non toasted chips in model solutions and young red wines

Ageing of wines on lees, the use of commercial yeast derivative products and the addition of oak chips to wine permit the release of different compounds such as mannoproteins and polysaccharides into wines during yeast autolysis. These compounds released can interact with phenolic compounds and/or aromatic compounds, also modifying wine sensory perception. For that reason, the aim of this work was to evaluate the interaction of phenolic and volatile compounds of wines with yeast lees, non-toasted oak wood chips and different commercial yeast derivative preparations in model wine solutions and in a real red wine. The results found in this study have shown that most of the phenolic and volatile compounds studied are adsorbed by wood and bound by lees in model wine solutions. However, in the model wines in general, the commercial yeast derivative products studied only interacted with the volatile compounds but not with the phenolic compounds. The adsorption of the phenolic compounds occurred in the first 15 days of treatment, remaining constant for 2 months; however, in the case of volatile compounds, these compounds initially displayed a retention effect, but after 30–60 days, the release of the previously bound compounds was instigated. The adsorption effect on the phenolic and volatile compounds in the model wine solution was not always the same as in the red wine studied, which highlights the important presence of other wine compounds in these interactions.     

Astringency,bitterness and color changes in dry red wines before and during oak barrel aging: An updated phenolic perspective review

To understand effects of using oak barrels on the astringency, bitterness and color of dry red wines, phenolic reactions in wines before and after barrel aging are reviewed in this paper, which has been divided into three sections. The first section includes an introduction to chemical reactivities of grape-derived phenolic compounds, a summary of the phenolic reactions that occur in dry red wines before barrel aging, and a discussion of the effects of these reactions on wine astringency, bitterness and color. The second section introduces barrel types that determine the oak barrel constituents in wines (primarily oak aldehydes and ellagitannins) and presents reactions between the oak constituents and grape-derived phenolic compounds that may modulate wine astringency, bitterness and color. The final section illustrates the chemical differences between basic oxidation and over-oxidation in wines, discusses oxygen consumption kinetics in wines during barrel aging by comparing different oxygen consumption kinetics observed previously by others, and speculates on the possible preliminary phenolic reactions that occur in dry red wines during oak barrel aging that soften tannins and stabilize pigments via basic oxidation. Additionally, sulfur dioxide (SO₂) addition during barrel aging and suitability of adopting oak barrels for aging wines are briefly discussed.     

Practical interventions that influence the sensory attributes of red wines related to the phenolic composition of grapes: a review

The phenolic composition of red wines is complex and intimately involved in colour, taste, mouth‐feel and aroma. There have been significant advances in knowledge of compounds with relatively simple structures, but understanding of those with more complex and probably diverse structures is challenging. A number of phenolic compounds may form temporary complexes with anthocyanins and/or be involved in reactions that lead to relatively stable coloured compounds. A wide range of phenolic compounds is implicated in the oral sensory attributes of red wines. Of particular importance are flavan‐3‐ols, including proanthocyanidins (PAs). The generally observed decline in the extractability of PAs during berry ripening is due to binding with cell wall material, which may occur within the developing berry and also from tissues brought into contact during processing. Studies have shown that exposure/reduced vigour results in an increasing proportion of skin PAs being extractable during wine making. Temperature and light influence anthocyanin with temperature probably being more important and the most sensitive stage being 1–3 weeks after véraison. Skin PAs are extracted earlier than those from seeds during wine‐making. Recent results suggest some rearrangement of skin and/or seed PAs occurs during vinification which involves the cleavage of large polymers or the aggregation of small ones. The polymeric material is particularly influential in wine astringency and is transformed by incorporation of anthocyanins into tannin‐like compounds during wine‐making and storage. Although some grape‐derived phenolic compounds contribute to the aroma of red wines, likely of greater importance are the effects of nonvolatile phenolics on the volatility of a diverse range of aroma compounds. Advances in analytical techniques are likely to provide greater insights into the structures and conformations of phenolic polymers and the role of cell wall material in relation to phenolic extraction and reaction during vinification. In relation to aroma, much more research is required to reveal the details of the interactions involving phenolics with volatile compounds. It seems likely that the ability to influence the relative extraction and subsequent reaction of skin and seed phenolics is important in the production of full colour, aromatic and long‐lived wines.     

High-added-value antioxidants obtained from the degradation of wine phenolics by Lactobacillus plantarum

Disposal of the waste from wine production has long been a problem for wineries, mainly because of the presence of phenolic compounds. In this study, we analyzed the antimicrobial activities of 10 wine phenolic compounds against Lactobacillus plantarum strains. Inhibition increased in this order: catechin = gallic acid < epicatechin = salicylic acid < methyl gallate = caffeic acid < ferulic acid = tryptophol < p-coumaric acid. The obtained results indicated that L. plantarum is able to grow in the presence of high concentrations of some wine phenolic compounds. Of the 10 compounds analyzed, only the hydroxycinnamic acids, gallic acid, and methyl gallate were metabolized by the four L. plantarum strains studied. Results also revealed that 4-vinylphenol and 4-vinylguaiacol are originated from p-coumaric and ferulic acids. These phenolic compounds are valuable intermediates in the biotechnological production of new fragrances. In addition, gallic acid and its ester, methyl gallate, are metabolized to produce the powerful antioxidant pyrogallol. Therefore, it might be possible to use L. plantarum strains to obtain high-added-value antioxidants from the degradation of phenolic compounds found in wine wastes.     

The study of phenolic compounds as natural antioxidants in wine

Plant phenolics present in fruit and vegetables, and that are particularly rich in red wine, have received considerable attention because of their potential antioxidant activity. Human consumption of antioxidants has many alleged health benefits, including protection against cardiovascular diseases, and, most recently, cancer. Red wines contain a variety of polyphenolic antioxidants. Five samples of commercial red wines from Spain and four phenolic compounds of red wine: gallic acid, trans-resveratrol, quercetin and rutin, have been studied. The total phenolics content and the total antioxidant activity (TAA) of wines was determined. The total phenolic content, determined according to the Folin-Ciocalteu method, varied from 1800 to 2300 mg/L, expressed as gallic acid equivalents (GAE). The antioxidative effects of wine phenolics were determined using a system based on the inhibition by antioxidants of the absorbance of the radical cation. The relationship between antioxidant activity of phenolic comounds, as hydrogen donating free radical scavengers, and their chemical structures was studied. Furthermore, the total antioxidant activity of the wines investigated was well correlated with phenol content. Thus, the results confirm that red wine polyphenols are, in vitro, significant antioxidants.     

Comparing the effects of exogenous abscisic acid on the phenolic composition of Yan 73 and Cabernet Sauvignon (Vitis vinifera L.) wines

Phenolic compounds from red wines exert a strong influence on wine quality. Abscisic acid (ABA) is essential for the physiological and biochemical function of plants, but few investigators have thoroughly researched its effects on phenolic compounds in dyer grape varieties. The effects of exogenous ABA treatment on the phenolic composition and individual anthocyanin and non-anthocyanin phenolic contents of Yan 73 and Cabernet Sauvignon wines from the ABA-treated grapes, including anthocyanins, flavan-3-ols, flavonols, phenolic acids, and stilbenes were compared. The phenolic compounds in the Yan 73 wine were different from those in the Cabernet Sauvignon wine. The phenolic content (anthocyanins and non-anthocyanins) of the Yan 73 wine was significantly higher than that of the Cabernet Sauvignon wine. The concentrations of the individual phenolic compounds were enhanced by the ABA treatment for the two different wine varieties. The effects on the compositions varied, a similar trend was observed for the ratios of Cy-derivative and Dp-derivative pigments from the two wine varieties, and all non-acylated pigments were enhanced. The stilbene content was enhanced, the ratios of flavan-3-ol dimers and dimer-glucosides were reduced, and the effects on the composition of other compounds varied between the two grape varieties.     

Antioxidant potential of single-variety red wines aged in the barrel and in the bottle

Wine constitutes a dynamic system in continuous evolution, in which numerous reactions involving polymerization and condensation take place between its phenolic compounds during the ageing process, which undoubtedly affect its structure and, very probably, its antioxidant effect. This study set out to evaluate the effect of ageing on the antioxidant potential of wine. A group of 162 wines were studied, of varying ages, which had undergone different ageing processes, both in the barrel and in the bottle, and which were prepared from different grape varieties and vintages. Total antioxidant capacity (ABTS, DPPH, DMPD, ORAC and FRAP), scavenger activity (HRSA and SRSA) and the biomarkers of oxidative stress (DNA-damage and ABAP-LP) were all analysed. The assay methods showed different behaviours for the same wines, thus the young wines presented higher indices for ABTS, DPPH and DMPD, whereas those that were aged showed higher indices for ABAP-LP and ORAC. Finally, the antioxidant potential of the wines in the study appeared not to be influenced by other factors, such as microoxygenation or grape variety.     

A kinetic study of the reactions of (+)‐catechin with aldehydes derived from toasted oak

The reactions between (+)‐catechin and representative oak wood furanic (furfuraldehyde, 5‐hydroxymethylfurfuraldehyde and 5‐methylfurfuraldehyde) and phenolic (vanillin and syringaldehyde) aldehydes in a wine‐like model solution were studied and the corresponding condensation kinetics at pH 3.0 and 3.5 were compared. A comparative study on the reactivity of these two representative families of aldehydes towards (+)‐catechin showed a large difference between them. When incubated separately with (+)‐catechin at both pH values, the reactions were faster with furanic aldehydes than with phenolic aldehydes. In mixtures containing (+)‐catechin and individual aldehydes, new compounds were identified by high‐performance liquid chromatography (HPLC)/UV–visible detection, some of which were characterised by liquid chromatography/electrospray ionisation mass spectrometry (LC/ESI‐MS). The increase in solution absorbance with time was closely linked to these new products. Copyright © 2007 Society of Chemical Industry     

Characterization of Uva Longanesi Red Wine by Selected Parameters Related to Astringency

This research represents a first attempt to chemically characterize wines produced from the autochthonous grape variety, Uva Longanesi, based upon the phenolic compounds responsible for its high astringency as confirmed by preliminary sensory analysis. In addition, a wine produced from Sangiovese, the most popular grape variety in the Emilia-Romagna region, was analyzed for comparative purposes. Results showed that Uva Longanesi wine had a higher pH, alcohol concentration, and total dry extract than the Sangiovese wine. With regards to phenolic constituents, the Uva Longanesi wine had higher color parameters and greater concentrations of total phenolics, including monomeric anthocyanins, small polymeric pigments, and tannins. The phenolic composition of Uva Longanesi wine was found to be responsible for the high reactivity of the wine during fining trials.     

Phenolic composition,colour, antioxidant activity and mineral profile of Cabernet Sauvignon wines

Phenolic compounds and mineral content constitute important quality parameters of wines. It is probably during ageing, that the greatest number of polymerisation and condensation reactions occurs, notably modifying the composition of the wine. The aim of this study was to characterise Cabernet Sauvignon wines of different vintages from two regions in Santa Catarina State, Brazil. It was not possible to clearly observe an evolution of the phenolic content and colour parameters in the different vintages of the wines. The ABTS method gave higher antioxidant value than DPPH, which showed higher correlation with total polyphenols. Principal components analysis showed differences between the wines, especially in relation to vintage. Also, the study allowed a clear separation of wines in relation to place of vineyards in terms of mineral composition.     

避雨栽培对赤霞珠葡萄酒非花色苷酚类的影响

研究避雨栽培对葡萄酒非花色苷酚类的影响,为酿酒葡萄避雨栽培技术的实施提供理论依据。采取简单避雨方式,以赤霞珠(Vitis vinifera L cv.Cabernet Sauvignon)葡萄为材料,在转色后进行避雨处理,以露地栽培为对照;葡萄收获后采用传统工艺酿制干红葡萄酒,测定其基本理化指标及非花色苷酚的种类和含量,获得如下结果:(1)避雨栽培降低了赤霞珠葡萄酒总酸、总酚和单宁含量,但差异不显著。(2)避雨栽培对一些单体非花色苷酚类含量存在显著影响,显著降低了黄烷醇类总量,但对黄酮醇和类黄酮酚总量无显著影响;极显著降低了苯甲酸、芪类和非类黄酮酚,增加了肉桂酸类含量。(3)对葡萄酒非花色苷酚类物质种类无影响,降低了非花色苷酚类总量但差异不显著。因此,在赤霞珠葡萄转色期采取避雨措施,对干红葡萄酒非花色苷酚类的影响不显著。     

葡萄酒中酚类物质抗氧化活性及构效关系

<正>酚类物质是芳香环上连有一个或多个羟基的低分子量有机化合物,其不但决定了葡萄酒的口感、色泽、贮藏寿命及稳定性,而且具有很强的抗氧化活性。葡萄酒中酚类物质对机体的防御作用归功于它特有的化学结构——酚羟基结构,它们具有供电子作用,通过提供活泼的氢捕捉机体内活性氧等自由基,阳断了自由基对机体的损伤。另外,葡萄酒中酚类物质也具有络合过渡金属离子能力、激活抗氧化酶的活性、减少α-生育酚自由基及降低氧化酶活性的能力。然而,尽管现在不同实验模式已证实了酚类化合物的这种多功效作用,但对于它们的构效关系的描述还不尽一致,因此,本文总结了酚类化合物(以类黄酮酚为例,见图1)在自由基清除作用和金属离子络合作用中关键的化学结构特征及影响,以旨为葡萄酒中酚类物质构效关系研究提供理论参考。