Antioxidant Capacity Of Wines Research Articles

Using abandoned unripe grape resources to solve the low-acid problem in the northwest wine region of China

Low acid is the main defect in the northwest wine region of China in recent years. The fermentation of unripe grape (UG) and wine grapes with low acid contents was carried out. Compared with control group (CK), the addition of UG addressed the core flaw that low acid grape bring to wine firstly, it significantly increased titratable acid, tartaric acid and malic acid while significantly decreasing alcohol and volatile acids in wine. Secondly, UG significantly improved wine color, the color parameters a*, b*, C* and L* were significantly increased to different degrees. At the same time, the addition of UG significantly improves other qualities of wine, including the phenolic substances and antioxidant capacity of wine. In addition, adding UGJ2% significantly improved the sensory quality, and pleasant volatile substances such as phenethyl alcohol, ethyl hexanoate, ethyl butyrate and isoamyl acetate were significantly increased, giving the wine more prominent floral and fruity aromas.

Direct NMR evidence for the dissociation of sulfur-dioxide-bound acetaldehyde under acidic conditions: Impact on wines oxidative stability

SO2 reaction with electrophilic species present in wine, including in particular carbonyl compounds, is responsible for the reduction of its protective effect during wine aging. In the present study, direct 1H NMR profiling was used to monitor the reactivity of SO2 with acetaldehyde under wine-like oxidation conditions. The dissociation of acetaldehyde bound SO2 was evidenced suggesting that released free SO2 can further act as an antioxidant. EPR and DPPH assays showed an increasing antioxidant capacity of wine with the increase in the concentration of acetaldehyde sulfonate. The presence of acetaldehyde sulfonate in wines was correlated with the overall antioxidant activity of wines. The first evidence of acetaldehyde bound SO2 dissociation provides a completely new representation of the long-term protection efficiency of SO2 during bottle aging.

Protective Effects of Fruit Wines against Hydrogen Peroxide—Induced Oxidative Stress in Rat Synaptosomes

This study aimed to evaluate, in vitro, the antioxidative potential of fruit wines produced from berry fruits (i.e., black chokeberry, blueberry, blackberry, and raspberry), cherry, and apple by different technological processes. For this purpose, the activities of antioxidant enzymes (catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD)) and malondialdehyde (MDA) content as a marker of membrane damage were determined in wine-treated synaptosomes with hydrogen peroxide-induced oxidative stress. All studied wines induced increased antioxidant enzyme activities and decreased MDA levels compared to hydrogen peroxide-treated synaptosomes (i.e., control). The highest SOD activity was observed in synaptosomes treated with blackberry wine (6.81 U/mg), whereas blueberry wine induced the highest catalase and glutathione peroxidase activities (0.058 U/mg and 0.017 U/mg, respectively). Black chokeberry proved to be the best in lipid peroxidation protection with the lowest MDA value (1.42 nmol/mg). Finally, principal component analysis and hierarchical cluster analysis additionally highlighted a higher antioxidant capacity of wines produced from dark-skinned fruits (i.e., blackberry, black chokeberry, and blueberry). The results suggest protective effects of the fruit wines against oxidative damage, and, accordingly, their promising application as functional food.

Anthocyanin and Phenolic Acids Contents Influence the Color Stability and Antioxidant Capacity of Wine Treated With Mannoprotein.

Wine is consumed by humans worldwide, but the functional components are lost and the color changes during its production. Here, we studied the effects of mannoprotein (MP) addition (0, 0.1, and 0.3 g/L) upon crushing and storage. We measured anthocyanins, phenolic acids profiles, color characteristics, and antioxidant activities of wine. The results showed that the addition of MP before fermentation significantly increased the total phenolic content (TPC), total anthocyanin content, total tannin content (TTC), total flavonoid content, and total flavanol content in wine, whereas the addition of MP during storage had the opposite effect. The addition of MP before alcohol fermentation significantly increased the amount of individual anthocyanins and individual phenolic acids, maintained the color, and increased the antioxidant capacity of wine. In addition, the addition of 0.3 g/L MP during storage increased the content of individual phenolic acids and TPC of wine. However, the addition of 0.1 g/L MP during storage significantly reduced the TPC, TAC, TTC, and individual anthocyanin content (except for malvidin-3-glucoside and malvidin-3-acetly-glucoside); meanwhile, the treatment attenuated the color stability and antioxidant capacity of wine. The results demonstrated that the addition of MP before alcohol fermentation could increase the functional components and improve the color stability and antioxidant capacity of wine.

Exploring the chemical space of white wine antioxidant capacity: A combined DPPH, EPR and FT-ICR-MS study

The chemical composition and functionality of molecular fractions associated with dry white wines oxidative stability remain poorly understood. In the present study, DPPH assay, electron paramagnetic resonance spectroscopy (EPR) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) were used to explore the chemical diversity associated with the antioxidant capacity (AC) of white wines. AC determined using the DPPH assay and EPR were complementary and enabled differentiation of wine samples into groups with low, medium, and high AC. Mass spectra variations associated with global DPPH- and EPR-derived indices enabled identification of 365 molecular markers correlated with samples with high AC, of which 32% were CHO compounds including phenolic and sugar derivatives, 20% were CHOS and 36% were CHONS compounds including cysteine-containing peptides. This study confirmed the importance of CHONS and CHOS compounds in the antioxidant metabolome of dry white wines. Knowledge about these compounds will enable better understanding of the oxidative stability of white wines and therefore aid in achieving optimum shelf life.

Impacts of leaf removal and shoot thinning on cumulative daily light intensity and thermal time and their cascading effects of grapevine (Vitis vinifera L.) berry and wine chemistry in warm climates

Leaf removal (LR), shoot thinning (ST) and their combination (LRST) are known to increase berry solar exposure affecting berry composition and consequently improving wine quality and antioxidant properties. We hypothesized that LR, ST or their combination (LRST) would affect flavonoid content during berry ripening by means of changes of the berry microclimate (light and temperature) as well as wine composition, quality, and antioxidant properties. Thermal time and sum of light intensity thresholds were different to achieve the maximum berry anthocyanin and flavonol contents. ST mostly affected wine characteristics by increasing alcoholic content, acidity, hue and phenolic substances. Wine antioxidant capacity decreased in ST wines likely by decreases in catechin and quercetin contents. ST and LRST increased proanthocyanidin polymerization and decreased monomeric flavan-3-ols, which may reduce wine bitterness and enhance astringency. Therefore, the management of canopy should take into account the warming trends in viticulture regions, rather than being applied preemptively.

Đánh giá khả năng duy trì hàm lượng polyphenol và hoạt tính kháng oxy hóa khi lên men rượu vang từ trái giác ở tỉnh Cà Mau sử dụng Saccharomyces cerevisiae CM3.2

Three-leaf cayratia (Cayratia trifolia L.) is a source of biological compounds that have the antioxidant capacity. The aims of this study were to evaluate the total polyphenol and antioxidant capacity of three-leaf cayratia and to investigate the suitable conditions for wine fermentation using Saccharomyces cerevisiae CM3.2. The suitable conditions for three-leaf cayratia wine fermentation were determined at 21.09 ºBrix, pH 4.5 and 105 cells/mL inoculation that could produce 12.46% v/v ethanol after 5 days of fermentation at 35°C. In 1 L scale fermentation, three-leaf cayratia wine had 12.63% v/v ethanol content with good sensorial properties. The total polyphenols and the antioxidant capacity of wine were 0.53 mg GAE/mL and 44.9%, respectively, which were not significantly different as in the three-leaf cayratia juice (polyphenol concentration of 0.61 mg GAE/mL and the antioxidant capacity of 51.4%).

A Novel Fluorimetric Method to Evaluate Red Wine Antioxidant Activity

In the light of the increasing use of red wine in the diet, due to its antioxidant properties, the availability of a simple and fast method to assay the antioxidant activity of this beverage is needed. Here we measured wine antioxidant capacity (WAC) via "crocin bleaching test", wine polyphenol content (WPC), via Folin Ciocalteu method, and fluorimetric response (WF) of 13 Italian red wines. A fairly good correlation between WAC and WF (R = 0.82) was found, thus validating the fluorimetric method as a simple, fast and cheap method to evaluate the antioxidant activity of red wines.

Melatonin Treatment Enhances the Polyphenol Content and Antioxidant Capacity of Red Wine

Melatonin and polyphenols are strong antioxidants, and melatonin is also a potential plant growth regulator. The role of melatonin in regulating polyphenol metabolism is unclear. This study assessed the primary impacts of exogenous melatonin treatment on phenolics accumulation and antioxidant capacity of the ‘Moldova’ wine. It was found that two times of 100 µmol·L−1 melatonin treatment clearly enhanced the endogenous melatonin content of ripened berries and wine. Further experiments indicated that melatonin treatment significantly increased the contents of total phenols, flavonoids and anthocyanins in wine. Additionally, the contents of most of the 20 detected individual phenolic compounds were significantly enhanced by melatonin treatment in wine. Particularly, the content of two non-flavonoid phenolic compounds (syringic and coumaric acid) and four anthocyanin compounds [Mv-3-Glu, Mv-3-(6-Coum)Glu-5-Glu, Dp-3-(6-AC)Glu and Dp-3-(6-Coum)Glu-5-Glu] were largely increased by melatonin treatment. In contrast, only Pn-3-(6-Coum)Glu was significantly reduced. Moreover, melatonin treatment significantly enhanced the antioxidant capacity of wine indicated by DPPH and FRAP assays. In summary, melatonin treatment enhanced the polyphenol content and antioxidant capacity of wine.

Effect of simulated digestion on the phenolic components of red grapes and their corresponding wines

The aim of this study was to evaluate the effect of the simulated gastro-intestinal (GI) digestion on the phenolic profile and the antioxidant capacity (AC) of grapes and red wines. Mouth and stomach digestion increased the bioaccesibility of TP (total polyphenols) in grapes, while in wine these compounds were already bioaccessible. Intestinal digestion reduced the bioaccessible polyphenols of grapes and wines, mainly due to the alkaline pH of the digestive fluid. Only 16% and 52% of the initial TP in grapes and wine, respectively, were found after assay (dialysed plus nondialysed fractions). Moreover, 21% and 39% of grape and wine AC, respectively, was conserved. In spite of the significant loss of polyphenols during digestion, both grapes and red wine still retain AC. Anthocyanins were less affected by human GI tract. Therefore, they could be the most relevant compounds to explain the AC of both grapes and red wine after GI.

Effects of Vinification Techniques Combined with UV-C Irradiation on Phenolic Contents of Red Wines.

Red wines are typically high in phenolic and antioxidant capacity and both of which can be increased by vinification techniques. This study employed 3 vinification techniques to assess the increase in phenolic compounds and antioxidant capacity. Wines were obtained from Boğazkere grape cultivar by techniques of classical maceration, cold maceration combined with ultraviolet light (UV) irradiation, and thermovinification combined with UV irradiation and changes in phenolic contents were examined. Total phenolic and anthocyanin contents and trolox equivalent antioxidant capacity of wines were measured spectrophotometrically and phenolic contents (+)-catechin, (-)-epicatechin, rutin, quercetin, trans-resveratrol, and cis-resveratrol were measured by High Pressure Liquid Chromatography with Diode Array Detection (HPLC-DAD). As a result of the study, the highest phenolic content except for quercetin was measured in the wines obtained by thermovinification combined with UV irradiation. We demonstrated that the highest phenolic compounds with health effect, total phenolic compounds, total anthocyanin, and antioxidant activity were obtained from thermovinification with UV-C treatment than classical wine making.

Research Note: Total Free Sulphydryls of Several White and Red Wines

Total free sulphydryl groups were assessed in several white and red wines. Ellman’s method was adapted to wine samples for the determination of total –SH groups. Total –SH groups of white wines, as glutathione, were in the range of 315 to 734 and of red wines in the range of 163 to 467 mg/L. In most cases, white wines exhibited higher values than red wines. The high total sulphydryls of white and red wines indicate their potential contribution to wine antioxidant capacity.

Phenolic composition of BRS Violeta red wines produced from alternative winemaking techniques: relationship with antioxidant capacity and sensory descriptors

The detailed phenolic composition, sensory profile and antioxidant capacity of red wines produced from the BRS Violeta grape cultivar have been studied. The alternative winemaking procedures of grape pre-drying and submerged cap have been assessed against the traditional treatment. Malvidin was the principal anthocyanidin of BRS Violeta wines, followed by delphinidin and petunidin. It was possible to detect 17 different types of pyranoanthocyanins derived from the five anthocyanidins in their non-acylated, acylated and coumaroylated forms, being vitisin A-types and hydroxyphenyl-pyranoanthocyanins the main forms detected. Pre-dried wine presented low concentrations of anthocyanins, suggesting that they were partially degraded by the thermal treatment as a result of cleavage of covalent bounds and/or by deglycosylation of the anthocyanin 3-glucosides. Submerged cap wine presented lower anthocyanin concentration due to the limited mechanical effect caused by the constant contact between pomace and must during maceration. The 3-glucoside of the myricetin was the principal flavonol, and large amounts of coumaric and caffeic acids were observed due to the high degree of hydrolysis of their precursors, named coutaric and caftaric acids. Both alternative winemaking procedures presented no differences in the flavan-3-ol concentrations, and the antioxidant capacity of the wines did not significantly differ. The lack of differences in the main sensory descriptive attributes showed that the alternative procedures have great potential to be applied as an alternative to the traditional treatment.

Chronocoulometry of wine on multi-walled carbon nanotube modified electrode: Antioxidant capacity assay

Phenolic antioxidants of wine were electrochemically oxidized on multi-walled carbon nanotubes modified glassy carbon electrode (MWNT/GCE) in phosphate buffer solution. Three oxidation peaks were observed at 0.39, 0.61 and 0.83V for red dry wine and 0.39, 0.80 and 1.18V for white dry wine, respectively, using differential pulse voltammetry at pH 4.0. The oxidation potentials for individual phenolic antioxidants confirmed the integral nature of the analytical signals for the wines examined. A one-step chronocoulometric method at 0.83 and 1.18V for red and white wines, respectively, has been developed for the evaluation of wine antioxidant capacity (AOC). The AOC is expressed in gallic acid equivalents per 1L of wine. The AOC of white wine was significantly less than red wine (386±112 vs. 1224±184, p<0.0001), as might be expected. Positive correlations were observed between gallic acid equivalent AOC of wine and total antioxidant capacity, based on coulometric titration with electrogenerated bromine (r=0.8957 at n=5 and r=0.8986 at n=4 for red and white wines, respectively).

Phenolic content and antioxidant capacity of Cypriot wines

Galanakis Ch.M., Kotanidis A., Dianellou M., Gekas V. (2015): Phenolic content and antioxidant capacity of Cypriot wines. Czech J. Food Sci., 33: 126–136. We characterised 12 wines (10 red, 1 sweet red, and 1 white) from different Cypriot cultivars in terms of their phe nolic, anthocyanin composition, and antioxidant capacity as determined by two activities: radical scavenging and ferric reducing ability. Two different phenolic fractions (tannin-free and 1-kDa permeate) were also isolated from Cypriot wines with an ultimate goal of investigating their role in the overall antioxidant capacity of wines. The results indicated that Maratheftiko and Lefkada cultivars had higher concentrations of o-diphenols, hydroxycinnamic acid derivatives, flavonols and anthocyanins compared to other Cypriot cultivars like Ofthalmo, Mavro, and Giannoudi. The higher concentrations of phenols did not always correspond to a higher antioxidant capacity, probably due to the antagonistic action observed between hydroxycinnamic acid derivatives, flavonols, and anthocyanins. The latest interactions restricted the release of flavonols’ advanced antiradical activity in wines.

Electropolymerized Eugenol‐MWNT‐Based Electrode for Voltammetric Evaluation of Wine Antioxidant Capacity

AbstractEugenol electropolymerization conditions on multiwalled carbon nanotube based glassy carbon electrode (MWNT/GCE) have been found. The polyeugenol/MWNT/GCE shows reversible redox steps of o‐quinone fragment in acidic media. Natural phenolic antioxidants are oxidized on polyeugenol/MWNT/GCE at 0.52 V excluding resveratrol (0.62 V). Differential pulse voltammetry on polyeugenol/MWNT/GCE was applied for the evaluation of wine antioxidant capacity (AOC). The AOC was expressed in catechin equivalents per 1 L of wine. The linear dynamic range is 1.00–250 µM with LOD and LOQ of 0.21 and 0.71 µM of catechin, respectively. Positive correlations for AOC with antioxidant activity (r=0.9840) and total phenolics content (r=0.9944) were observed.

A novel hybrid flow-injection/sequential-injection methodology for the rapid evaluation of the total antioxidant capacity of wines using inhibition of the alkaline luminol–potassium permanganate chemiluminescent reaction

This work reports the development and validation of a novel hybrid flow injection/sequential injection (FI–SI) method with chemiluminescence (CL) detection for the rapid evaluation of the total antioxidant capacity (TAC) of wines. The method is based on the inhibition of the CL reaction between luminol and potassium permanganate in alkaline medium by the antioxidants in the sample. Zones of sample, potassium permanganate and alkaline luminol were sequentially injected into the carrier stream of the FI–SI manifold. As the zones were delivered to the CL detector, they overlapped and antioxidants in the samples scavenged a portion of potassium permanganate causing a decrease in the CL intensity. The statistical significance of the main chemical and instrumental conditions was studied using a two-level Plackett–Burman experimental design approach and the significant variables were further selected using a univariate approach. The method was validated in terms of linearity, limits of detection (LOD) and quantification (LOQ), accuracy (trueness and precision), matrix effects, and robustness. The linear range for gallic acid (used to express the TAC) was 0.90μmolL−1–15μmolL−1, the LOD was 0.30μmolL−1 and the LOQ was 0.90μmolL−1. The precision of the method (expressed as the % relative standard deviation) was better than 6.4% and the % recoveries in wines were ≥93%. The proposed FI–SI CL method was compared with the DPPH method for the analysis of 25 wine samples.

Biotechnological Strategies for Controlling Wine Oxidation

Apart from the controversial positive effects of moderate wine consumption on human health, wine antioxidant capacity plays a key role in winemaking technology. From juice extraction to bottle storage, oxygen management is one of the most critical points for making quality wines. In the past, the protection of juice and wine from oxidations was based on the sole use of sulfur dioxide; more recently, the toxicity and the allergenic potential of this additive, together with the increased knowledge on wine oxidation mechanisms, have given rise to new biotechnological approaches and producing trends, leading to a significant reduction of sulfites in winemaking. The aim of this paper is to review the oxidation mechanisms of grape juice and wine and to discuss the opportunities to reduce as much as possible sulfur dioxide addition by a proper management of alcoholic and malolactic fermentation and by the supplementation of some important yeast nutritional factors (e.g., thiamine). The use of natural antioxidants complementing the activity of sulfites (i.e., ascorbic acid, glutathione, yeast lees, and yeast derivatives) is also discussed.

DPPH Assay Adapted to the FIA System for the Determination of the Antioxidant Capacity of Wines: Optimization of the Conditions Using the Response Surface Methodology

The objective of the present work was to adapt the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay to a system of flow injection analysis (FIA) of merging zones to determine the antioxidant capacity of wine samples. The conditions of the FIA system proposed here were optimized with the response surface methodology using central composite rotatable design. The optimization parameters studied here were the carrier flow rate, the length of the sampling and reagent loops, and the length of the reaction coil. The experimental data were fitted to a polynomial model, and the optimal conditions were: flow rate of 1.12 mL min−1, loop length of 18.5 cm, and reaction coil length of 234.60 cm. The limits of detection and quantification were 2.65 and 8.82 μM of Trolox, respectively. The method proposed had an analytical frequency of 41 analyses per hour and a reagent consumption economy of 57.3 % for DPPH in relation to the conventional method. The results of the antioxidant activities of the wine samples obtained with the proposed method were correlated and compared to those of the conventional method.

Color, Ellagitannins, Anthocyanins, and Antioxidant Activity of Andean Blackberry (Rubus glaucus Benth.) Wines

Twenty-eight blackberry ( Rubus glaucus Benth.) wines elaborated under different processing conditions were analyzed for total phenolics, ellagitannins, anthocyanins, color, and antioxidant activity. Ellagitannins were the main phenolic compounds and the most determinant factor in the antioxidant capacity of wines (r = 0.980). The major anthocyanins were cyanidin 3-rutinoside (64 ± 6%) and cyanidin 3-glucoside (19 ± 4%), followed by several minor compounds (17 ± 4%). Two of them were native blackberry anthocyanins, namely, cyanidin 3-rutinoside-5-glucoside and cyanidin 3-xylorutinoside. The remaining seven compounds were anthocyanin-related pigments generated during and after the alcoholic fermentation, identified as A-type and B-type vitisins and hydroxyphenylpyranoanthocyanins. The presence of fruit solids in contact with the liquid fraction during fermentation and the ratio of water to fruit employed in the preparation of the musts had a great impact on the content of ellagitannins, total phenolics, and the antioxidant activity of wines and a minor impact on their color and anthocyanin composition.