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ABSTRACT: The C-glucosidic ellagitannins are found in wine as a result of its aging in oak barrels or in stainless steel tanks with oak chips. Once dissolved in this slightly acidic solution, the C-glucosidic ellagitannins vescalagin can react with nucleophilic entities present in red wine, such as ethanol, catechin, and epicatechin, to generate condensed hybrid products such as the β-1-O-ethylvescalagin and the flavano-ellagitannins (acutissimin A/B and epiacutissimin A/B), respectively. During this study, we first monitored the extraction kinetic and the evolution of the eight major oak-derived C-glucosidic ellagitannins in red wines aged in oak barrels or in stainless steel tank with oak chips. Their extraction rates appeared to be faster during red wine aging in stainless steel tanks with oak chips. However, their overall concentrations in wines were found higher in the wine aged in barrels. The formation rates of the vescalagin-coupled derivatives were also estimated for the first time under both red wine aging conditions (i.e., oak barrels or stainless steel tanks with oak chips). As observed for the oak-native C-glucosidic ellagitannins, the concentrations of these vescalagin derivatives were higher in the red wine aged in oak barrels than in stainless steel tanks with oak chips. Despite these differences, their relative composition was similar under both red wine aging conditions. Finally, the impact of the oak chips size and toasting level on the C-glucosidic ellagitannins concentration in wine was also investigated.
Analytical and Bioanalytical Chemistry 04/2011; 401(5):1531-9. · 3.78 Impact Factor
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04/2010: pages 81 - 137; , ISBN: 9781444323375
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Stefan Chassaing,
Dorothée Lefeuvre,
Rémi Jacquet,
Michael Jourdes,
Laurent Ducasse,
Stéphanie Galland,
Axelle Grelard, Cédric Saucier,
Pierre-Louis Teissedre,
Olivier Dangles,
Stéphane Quideau
Annalen der Chemie und Pharmacie 11/2009; 2010(1):55 - 63. · 3.10 Impact Factor
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ABSTRACT: This work outlines the results from an investigation to determine the effect of the oxygen dissolved at bottling and the specific oxygen barrier properties of commercially available closures on the composition, color and sensory properties of a Bordeaux Sauvignon Blanc wine during two years of storage. The importance of oxygen for wine development after bottling was also assessed using an airtight bottle ampule. Wines were assessed for the antioxidants (SO(2) and ascorbic acid), varietal thiols (4-mercapto-4-methylpentan-2-one, 3-mercaptohexan-1-ol), hydrogen sulfide and sotolon content, and color throughout 24 months of storage. In addition, the aroma and palate properties of wines were also assessed. The combination of oxygen dissolved at bottling and the oxygen transferred through closures has a significant effect on Sauvignon Blanc development after bottling. Wines highly exposed to oxygen at bottling and those sealed with a synthetic, Nomacorc classic closure, highly permeable to oxygen, were relatively oxidized in aroma, brown in color, and low in antioxidants and volatile compounds compared to wines sealed with other closures. Conversely, wines sealed under more airtight conditions, bottle ampule and screw cap Saran-tin, have the slowest rate of browning, and displayed the greatest contents of antioxidants and varietal thiols, but also high levels of H(2)S, which were responsible for the reduced dominating character found in these wines, while wines sealed with cork stoppers and screw cap Saranex presented negligible reduced and oxidized characters.
Journal of Agricultural and Food Chemistry 11/2009; 57(21):10261-70. · 2.82 Impact Factor
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ABSTRACT: Grape variety [Cabernet Sauvignon (CS) and Merlot (M)] effect on the proanthocyanidin composition and sensory perception of wine grapes from Bordeaux vineyards for two successive vintages (2006 and 2007) is reported. The flavan-3-ol monomers [(+)-catechin = C, (-)-epicatechin = EC, (-)-epicatechin-O-gallatte = ECG] and the proanthocyanidin oligomers [dimers B1, B2, B3, and B4 and trimer Cat-Cat-Epi (T)] in grape seed and skin tannin extracts were identified and quantified at harvest. Proanthocyanidin subunit compositions, percentage of galloylation (%G), and percentage of prodelphinidins (%P) as well as mean degree of polymerization (mDP) of the proanthocyanidin fraction were determined. Sensory analysis concerning the astringency and bitterness intensity of the proanthocyanidins of skin and seed tannin extracts was also performed. The results showed that proanthocyanidin composition can be greatly affected by grape variety. For both vintages between CS and M, significant differences were found on mDP (p < 0.05) in seed tannin extracts, whereas in skin tannin extracts, significant differences were observed for %G and %P (p < 0.05). Sensory analysis showed that grape variety influenced neither astringency nor bitterness intensity perception for both skin and seed tannin extracts for the two successive vintages studied. A positive correlation was found between astringency intensity, mDP, and B3 content in skin tannin extracts.
Journal of Agricultural and Food Chemistry 12/2008; 57(2):545-53. · 2.82 Impact Factor
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ABSTRACT: The main routes of oxygen ingress into wine bottles through "technical" cork stoppers (Neutrocork), natural cork stoppers, and synthetic closures (Nomacorc) were investigated. A comparison was made among closures left uncovered (controls), closures with the closure-glass interface covered, and closures completely covered with a polyurethane impermeable varnish. The oxygen ingress into the bottles was measured by a nondestructive colorimetric method. Technical cork stoppers were essentially impermeable to atmospheric oxygen during the first 24 months of storage. Oxygen within natural corks diffused slowly but continuously into the bottles over the first 12 months of storage and in very tiny amounts through the cork-glass interface the 12 months thereafter. Nomacorc synthetic closures were permeable to atmospheric oxygen, mainly after the first month of storage.
Journal of Agricultural and Food Chemistry 07/2007; 55(13):5167-70. · 2.82 Impact Factor
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ABSTRACT: A new compound resulting from the oxidative degradation of maldivin 3-O-glucoside under acid conditions was detected in a wine model solution stored under 90 and 25 degrees C. It was isolated by semipreparative HPLC, and its structure was elucidated by UV-vis spectra, mass spectrometry (LC/MS), and NMR spectroscopy (1-D and 2-D). The compound was identified as 8-beta-d-glucopyranosyl-2,4-dihydroxy-6-oxo-cyclohexa-2,4-dienyl acetic acid (anthocyanone A), which results from nucleophilic attack of hydrogen peroxide to maldivin 3-O-glucoside through a Baeyer-Villiger oxidation followed by other oxidations steps.
Journal of Agricultural and Food Chemistry 05/2007; 55(7):2698-704. · 2.82 Impact Factor
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ABSTRACT: Previous studies showed that alcohol-free extracts of Armagnac, an oak cask aged spirit rich in polyphenols, inhibit human platelet function in vitro and in vivo, in an experimental rat arteriovenous shunt thrombosis model and in human healthy volunteers. To identify active compounds, we fractionated a freeze-dried extract of a 10-year-old Armagnac using successively chloroform, diethyl ether and ethyl acetate. The 4 resulting fractions were tested on in vitro human platelet aggregation induced by ADP and in vivo on arteriovenous shunt thrombosis after 10 days oral treatment in rats. Active components were found mainly in fractions 1 and 3: at the highest concentration (2.4 10(-2) g/l), in vitro ADP-induced aggregation was inhibited by 62.7+/-2.1% and 51.2+/-3.8% for F1 and F3, respectively, vs 18.9+/-2.4% and 13.9+/-0.4% for fractions 2 and 4 and 33.6+/-1.5% for the crude extract. There was a significant decrease in thrombus weight with the crude extract and all fractions tested after 10 days treatment with 2.5 mg/kg/day orally, greatest with fraction 1. Characterisation of phenol content showed that fraction 1, the most biologically active, was essentially devoid of ellagic acid and ellagitannins, the polyphenols initially thought responsible for the effect, whereas fraction 2 which was mostly inactive, was the richest in polyphenols. CONCLUSION: The antiplatelet and antithrombotic activity of Armagnac seems mostly unrelated to polyphenols.
Thrombosis Research 02/2007; 119(4):407-13. · 2.44 Impact Factor
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ABSTRACT: For two successive years, cell walls were isolated from the internal part of skin cells of Vitis vinifera L. cv. Cabernet Sauvignon grape berries grown in a vineyard. Procyanidin localization and composition were determined over the course of development. Tannins were mainly localized in the inner cell fraction, due to their biosynthesis and storage. Cell wall tannins always exhibited a higher mean degree of polymerization as compared to the internal cell fraction, which had a constant mDP. The mDP of cell wall tannins also tended to increase at the end of maturation. Our results suggest tannin polymerization near the cell wall but an aggregation in the vacuole during growth. The tannin composition was typical of skins, and small differences were noted between the two cell parts. Surprisingly, epigallocatechin-3-gallate was also detected, although in a very small amount. Epicatechin was present in significant proportions in both fractions, especially as an extension subunit, while epigallocatechin was likewise abundant, also as a terminal subunit. Last, procyanidin composition and organization seemed to be characteristic of the Cabernet Sauvignon variety.
Journal of Agricultural and Food Chemistry 01/2007; 54(25):9465-71. · 2.82 Impact Factor
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ABSTRACT: Wine bottle aging is extremely dependent on the oxygen barrier properties of closures. Kinetics of oxygen ingress through different closures into bottles was measured by a nondestructive colorimetric method from 0.25 to 2.5 mL of oxygen. After 12, 24, and 36 months of storage, only the control (glass bottle ampule) was airtight. Other closures displayed different oxygen ingress rates, which were clearly influenced by the closure type and were independent of bottle storage position (upright, laid down) for most of the closures tested, at least during the first 24 months of the experiment under controlled conditions. The oxygen ingress rates into bottles were lowest in screw caps and "technical" corks, intermediate in conventional natural cork stoppers, and highest in the synthetic closures.
Journal of Agricultural and Food Chemistry 10/2006; 54(18):6741-6. · 2.82 Impact Factor
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ABSTRACT: In dry white wines, two different forms of instability occur: (i) substantial yellow or yellow-green deposits are observed principally due to flavonol quercetin; and (ii) protein instability leads to protein casse. Polyvinyl polypyrrolidone (PVPP) is used to adsorb phenols from beverages, and bentonite is used to eliminate heat instable protein. However, in both cases, their effects are still largely unknown. This study uses a multitechnique approach to gain a better molecular understanding of the association of polyphenol aglycones with PVPP compared to that of glucosides with PVPP. The work demonstrates, that with aglycones, three forces drive complex formation: hydrophobic interaction, H bonds, and van der Waals bonds. With glucosides, the sugar moiety removes or reduces these driving forces. Thus, if the interaction between proteins and polyphenols is responsible for haze and precipitates, as is classically assumed, PVPP could prevent quercetin sedimentation.
Journal of Agricultural and Food Chemistry 07/2006; 54(12):4383-9. · 2.82 Impact Factor
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ABSTRACT: Polyphenolic nonahydroxyterphenoyl-containing C-glycosidic oak ellagitannins are found in wine as a result of the aging of this beverage in oak-made barrels. Once in the slightly acidic wine (pH approximately 3-4), some of these complex natural products such as (-)-vescalagin (1), but not its C-1 epimer (-)-castalagin (2), can capture grape-derived nucleophilic entities such as ethanol, the flavanols catechin (10a) and epicatechin (10b), the anthocyanin oenin (13b), and the thiolic glutathione (16) to furnish condensation products with retention of configuration at the C-1 locus. A computer-aided rationale of this high diastereoselectivity is given. These condensation products can contribute to the modulation of organoleptic properties of the wine, as evidenced by the 23 nm bathochromic shift color absorbance observed with the novel oenin-based anthocyano-ellagitannin (15b). Hydrolysis of 1 under solvolytic conditions furnished another novel compound that we refer to as vescalene (21), in addition to the known (-)-vescalin (18). Of pharmacological importance is the fact that most of these found-in-wine water-soluble ellagitannin derivatives are much more potent than etoposide (VP-16) at inhibiting top2-mediated DNA decatenation in vitro (top2=topoisomerase II)). The known (-)-vescalin (18) and the novel vescalene (21) fully inhibited top2 at 10 microM concentration!
Chemistry 12/2005; 11(22):6503-13. · 5.93 Impact Factor
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ABSTRACT: Oxygen is one of the most important factors determining the aging potential of bottled wine, and oxygen diffusion into bottled wine is extremely dependent on the sealing effectiveness of the closure. A nondestructive colorimetric method was developed to measure oxygen diffusion from 1 to 9.8 mg/L during the postbottling period. This method was used to study oxygen diffusion through different closures available on the market. After 365 days of horizontal storage, only the control bottle was impermeable to atmospheric oxygen; all other closures exhibited variable rates of oxygen diffusion, which were much greater in the first month than in the following months. It was shown that the rate of diffusion was clearly influenced by the type of closure material used.
Journal of Agricultural and Food Chemistry 10/2005; 53(18):6967-73. · 2.82 Impact Factor
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ABSTRACT: (+)-Catechin reaction with two aldehydes (acetaldehyde and glyoxylic acid) was studied in winelike model solution. The two aldehydes were reacted either individually or together with (+)-catechin and in molar excess. The reactions were followed by HLPC-UV and HPLC-ESI/MS to monitor (+)-catechin disappearance as well as dimer and polymer appearance. In all reactions a reaction order of close to 1 for (+)-catechin disappearance was observed. (+)-Catechin disappearance was slower in the presence of acetaldehyde (t(1/2) = 6.7 +/- 0.2 h) compared to glyoxylic acid (t(1/2) = 2.3 +/- 0.2 h). When the two aldehydes were reacted together, (+)-catechin disappearance was faster (t(1/2) = 2.2 +/- 0.5 h). When aldehydes were reacted separately, the dimer appearance was independent of the type of aldehyde used but the ethyl-bridged dimer disappearance was slower with acetaldehyde. When aldehydes were reacted together, the dimer appearance changed. Ethyl-bridged dimers appeared before carboxymethine-bridged dimers, and their disappearance occurred earlier. Copolymers containing both ethyl and carboxymethine bridges were also observed.
Journal of Agricultural and Food Chemistry 10/2005; 53(19):7552-8. · 2.82 Impact Factor
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Angewandte Chemie International Edition 01/2004; 42(48):6012-4. · 13.45 Impact Factor
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ABSTRACT: The (+)-catechin−acetaldehyde condensation was studied as a model for tannin polymerization and precipitation in red wines. It was shown by using LSIMS that reaction products are catechin polymers with CH−CH3 bridges at two reaction sites. Before the end of monomer conversion into polymers there is an aggregation followed by a phase separation. Particle mean diameter was measured by dynamic light scattering directly in reaction medium. Comparison between particle and polymer sizes showed that polymers aggregate into colloidal intermediates before a large polymerization degree is reached. These particles then coagulate further, which leads to polymer precipitation. This colloidal behavior is explained by hydrophobic forces since aggregates and precipitate redissolve in ethanol. Keywords: Tannin; wine aging; colloid; catechin; acetaldehyde
04/1997;
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ABSTRACT: The effect of three different maceration times (3, 6, and 10 days) on the anthocyanin composition of Boğazkere and Öküzgözü red wines produced in Turkey was studied. A high-performance liquid chromatographic method coupled with diode-array detection was used to identify and quantify anthocyanin compounds of the wines. Fourteen different anthocyanin compounds were detected in Boğazkere wines while the Öküzgözü wines had thirteen compounds. It was observed that the concentration of anthocyanin compounds of the Boğazkere wines was much higher compared to the Öküzgözü wines. Malvidin-3-glucoside and its acylated esters were the major anthocyanins in both wines. It was observed that the amount of the total anthocyanin compounds in both wines increased to the maximum value within 6 days of the skin maceration time.
Journal of Food Engineering. 77(4):1012-1017.
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ABSTRACT: A method to measure specific β(1,3)-glucanase activity in wines has been developed, and is based on the measurement of the kinetics of glucose release in the presence of laminarin (a β(1,3)-glucan from Laminaria digitata). The reaction time and substrate amount have been optimised to allow for measurements in wine conditions. The optimised method has been used to measure the efficiency of a commercial enzyme preparation in wines in relation to filterability. The results indicate that despite the inhibition of wine constituents, β-glucanase activities were present in all wines after enzyme addition. The filterability of the wines significantly increased after enzyme addition as measured by a standardised procedure (Vmax index).
Enzyme and Microbial Technology 34(6):537-543. · 2.37 Impact Factor
