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1.
The amounts of myricetin, quercetin, and kaempferol were analyzed in 16 red and 2 white berry and grape wines after acid hydrolysis using an RP-HPLC method with diode array detection. The red berry wines analyzed were made mainly from black currant, crowberry, and bog whortleberry, i.e., berries rich in flavonols. The red grape wines were made mainly from Cabernet Sauvignon or Merlot grapes in several countries. The white wines studied were gooseberry and white currant wines and Chardonnay and Riesling wines. The amount of myricetin ranged from 3.8 to 22.6 mg L(-1) in red berry wines and from 0 to 14.6 mg L(-1) in red grape wines. The amount of quercetin was from 2.2 to 24.3 mg L(-1) red berry wines and from <1.2 to 19.4 mg L(-1) in red grape wines. Low levels of kaempferol were found in all red berry wines and in 9 red grape wines. The total concentration of these flavonols was from 6 to 46 mg L(-1) (mean 20 mg L(-1)) in red berry wines and from 4 to 31 mg L(-1) (mean 15 mg L(-1)) in red grape wines. Small amounts of quercetin were found in white currant and gooseberry wines, whereas no flavonols were detected in white grape wines. These results demonstrate that the contents of flavonols in red  相似文献   

2.
Phenolics from grapes and wines can play a role against oxidation and development of atherosclerosis. Levels of phenolics, major catechins [(+)-catechin, (-)-epicatechin, procyanidin dimers B1, B2, B3, and B4], phenolic acids (gallic acid and caffeic acid), caftaric acid, malvidin-3-glucoside, peonidin-3-glucoside, and cyanidin-3-glucoside were quantified by HPLC with UV detection for 54 French varietal commercial wines taken from southern France to study the antioxidant capacity and the daily dietary intake of these compounds for the French population. The highest antioxidant capacity was obtained with red wines and ranged from 12.8 mmol/L (Grenache) to 25.2 mmol/L (Pinot Noir). For white wines, Chardonnay enriched in phenolics by special wine-making was found to have an antioxidant capacity of 13.8 mmol/L, comparable to red wine values. For red wines classified by vintages (1996-1999) antioxidant capacities were approximately 20 mmol/L and then decreased to 13.4 mmol/L for vintages 1995-1991. Sweet white wines have 1.7 times more antioxidant capacity (3.2 mmol/L) than dry white wines (1.91 mmol/L). On the basis of a still significant French wine consumption of 180 mL/day/person, the current daily intake of catechins (monomers and dimers B1, B2, B3, and B4) averaged 5 (dry white wine), 4.36 (sweet white wines), 7.70 (rosé wines), 31.98 (red wines), and 66.94 (dry white wine enriched in phenolic) mg/day/resident for the French population. Red wine, and particularly Pinot Noir, Egiodola, Syrah, Cabernet Sauvignon, and Merlot varieties, or Chardonnay enriched in phenolics during wine-making for white varieties contribute to a very significant catechin dietary intake.  相似文献   

3.
The 2-methoxy-3-isobutylpyrazine content in grapes and red wines was assayed by stable isotope dilution gas chromatography-mass spectrometry, following vapor extraction and purification on a cation resin microcolumn. The threshold beyond which the green bell pepper character is marked in wines has been determined. From a comparison of the 2-methoxy-3-isobutylpyrazine concentrations of 50 red Bordeaux and Loire wines from different vintages and grape varieties (Cabernet Sauvignon, Cabernet franc, and Merlot) with the intensity of the green bell pepper character as perceived on tasting, the threshold value was estimated to be 15 ng/L. Statistical analysis of the 2-methoxy-3-isobutylpyrazine concentrations of 89 red Bordeaux wines showed that Cabernet wines were more commonly affected by this vegetative character. Changes in the 2-methoxy-3-isobutylpyrazine concentration as the grapes ripen are affected by the environmental and cultural conditions (soil, climate, training system, etc.). A very good correlation was shown between the breakdown of malic acid and 2-methoxy-3-isobutylpyrazine as the grapes ripened, irrespective of grape variety, type of soil, or weather conditions.  相似文献   

4.
Grapes and wines are now known to constitute a rich source of phenolics such as stilbenes and flavonoids. These compounds have been shown to have cancer chemopreventive activity and potential beneficial effects on cardiovascular diseases thanks to their antioxidant and antiplatelet properties. However, because little is known about African wines and their phenolic compositions, we investigated wine samples from North Africa. A three-step method was used for the fractionation of the Merlot variety wine: column chromatography followed by centrifugal partition chromatography and reversed-phase semipreparative high-performance liquid chromatography (HPLC). Six polyphenolic compounds of the Merlot variety (from Algeria) were isolated and identified by NMR spectroscopy, five of which are known (trans-resveratrol, trans-piceid, trans-epsilon-viniferin, pallidol, and astilbin) and one that is reported for the first time in wine, (+)-hopeaphenol, a stilbene tetramer. Furthermore, these molecules were quantified in 10 commercial wines from North Africa by means of an analytical HPLC system coupled with diode array detection. Differences in concentrations were found ranging in mg/L from 4.6 to 45 (trans-piceid), 0.66 to 3.45 (trans-resveratrol), 0.2 to 1.2 (trans-epsilon-viniferin), 0.2 to 9.2 (pallidol), 0.3 to 3.8 (hopeaphenol), and 10.8 to 24.22 (astilbin). Such a high level of pallidol and astilbin has never been recorded in wine. North African wines may contribute to a significant proportion of dietary intake of stilbene and astilbin, which may have health benefits.  相似文献   

5.
The sensory properties of wine are influenced by the chemical composition of the grapes used to produce them. Identification of grape and wine chemical markers associated with the attributes perceived by the consumer of the wine will enable better prediction of the potential of a parcel of grapes to produce wine of a certain flavor. This study explores the relationships between Cabernet Sauvignon grape volatile composition and wine volatile profiles with the sensory properties of wines. Twenty grape samples were obtained from nine vineyard sites across three vintages and wines vinified from these parcels using controlled winemaking methods. The volatile composition of the grapes were analyzed by SBSE-GCMS, the wines were analyzed by SPME-GCMS, and these data sets were compared to that obtained from the sensory analysis of the wines. Statistical treatment of the data to account for vintage and region effects allowed underlying relationships to be seen between wine sensory attributes and wine or grape volatile components. The observed associations between grape or wine volatile compounds and wine sensory attributes has revealed target compounds and pathways whose levels may reflect the biochemical effects on grape composition by differing growth conditions during berry development and ripening. The compounds identified in this study may be useful grape or wine markers for potential wine sensory characteristics.  相似文献   

6.
Preliminary investigations revealed that the proximity of Eucalyptus trees to grapevines can directly influence the concentration of the aroma compound 1,8-cineole present in the corresponding red wines. For two different vineyards, the closer the grapevines were to the trees, the greater was the amount of 1,8-cineole in the wines elaborated from those grapes. This led us to carry out further studies to quantify the levels of 1,8-cineole found in grape berries, leaves, and stems at set distances from Eucalyptus trees over multiple vintages. Generally, the highest concentration of 1,8-cineole was found in the grapevine leaves, followed by grape stems and then grapes. In each sample type, we observed greater concentrations of 1,8-cineole in samples closer to the trees. Various fermentation treatments carried out with Shiraz grapes showed that matter other than grapes (MOG, e.g., Eucalyptus or grape leaves) could contribute significant amounts of 1,8-cineole to the finished wines. These studies confirmed that vineyard position and winemaking conditions can determine the 1,8-cineole concentration in red wine. The fermentation study also showed for the first time that the concentration of rotundone in red wine can be strongly influenced by grapevine leaves and stems in the ferment.  相似文献   

7.
The production pattern for ochratoxin A in grapes inoculated with Aspergillus carbonarius and changes in its concentration during raisining of Merlot, Syrah, Tempranillo, and Cabernet Sauvignon red grapes and Pedro Ximenez white grape were studied. Grapes were chamber-dried under controlled temperature and humidity conditions, with and without dipping pretreatments in alkaline emulsions of olive oil or ethyl oleate. Based on the results for the grapes that developed the fungus (Merlot and Pedro Ximenez), a temperature of 50 °C in the absence of dipping stopped ochratoxin A production and even degraded part of the toxin already formed. Both dipping pretreatments facilitated removal of the toxin and led to its virtually complete disappearance. However, dipping in the ethyl oleate emulsion caused substantial changes in the sensory characters of the musts obtained from the raisins, so it should be avoided to ensure the expected quality in the sweet wines elaborated from them.  相似文献   

8.
The chemical compound 2-furanmethanethiol (2FM), with a strong roast coffee aroma, has been identified in sweet white wines made from the Petit manseng grape variety, and in certain red Bordeaux wines (made from the Merlot, Cabernet franc, and Cabernet sauvignon grape varieties). This was done by extracting specific volatile thiols using p-hydroxymercuribenzoate. The 2FM has also been found in toasted oak used in barrel-making. All the Petit manseng sweet white wines and some of the red Bordeaux wines analyzed contained between a few ng/L and several dozen ng/L of 2FM. Taking into account its very low perception threshold (0.4 ng/L in a model hydro alcoholic environment), 2FM could therefore contribute to the roast coffee aroma of certain wines.  相似文献   

9.
In the present work, the aroma profiles of wines elaborated from sound and sour rot-infected grapes as raw material have been studied by sensory analysis, gas chromatography-olfactometry (GC-O), and gas chromatography-mass spectrometry (GC-MS), with the aim of determining the odor volatiles most likely associated with this disease. The effect of sour rot was tested in monovarietal wines produced with the Portuguese red grape variety Trincadeira and in blends of Cabernet Sauvignon and sour rotten Trincadeira grapes. Wines produced from damaged berries exhibited clear honey-like notes not evoked by healthy samples. Ethyl phenylacetate (EPhA) and phenylacetic acid (PAA), both exhibiting sweet honey-like aromas, emerged as key aroma compounds of sour rotten wines. Their levels were 1 order of magnitude above those found in controls and reached 304 and 1668 μg L(-1) of EPhA and PAA, respectively, well above the corresponding odor thresholds. Levels of γ-nonalactone also increased by a factor 3 in sour rot samples. Results also suggest that sour rot exerts a great effect on the secondary metabolism of yeast, decreasing the levels of volatiles related to fatty acids and amino acid synthesis. The highest levels of γ-decalactone of up to 405 μg L(-1) were also found in all of the samples, suggesting that this could be a relevant aroma compound in Trincadeira wine aroma.  相似文献   

10.
Piceid, the major resveratrol derivative in grape juices   总被引:6,自引:0,他引:6  
The levels of trans-piceid, cis-piceid, trans-resveratrol, and cis-resveratrol have been measured in 36 grape juices using an HPLC system with spectral analysis of eluting peaks. The piceid (glucosides) were the major component in the grape juices. In red grape juices the average concentrations were 3.38 mg/L for trans-piceid, 0.79 mg/L for cis-piceid, 0.50 mg/L for trans-resveratrol, and 0.06 mg/L for cis-resveratrol. In white grape juices the levels were, on average, 0.18 mg/L for trans-piceid, 0.26 mg/L for cis-piceid, and 0.05 mg/L for trans-resveratrol, and cis-resveratrol was not detected in any sample. Levels of total resveratrol (trans- and cis-resveratrol and -piceid) found in red and in white grape juices are similar to those described in Spanish red and white wines. Due to their resveratrol content, as well as other phenolics, grape juices may have a beneficial health effect of interest to those who cannot drink wine.  相似文献   

11.
The phenolic composition of wine depends on, among other factors, the grapes used to make it. In this sense, knowledge of the chemical composition of grapes and its association with the resulting wines is an important tool to determine if there is a relationship between the phenolic composition of grapes and the price that these wines obtain in the market. For this purpose, grape skins and seeds from the cultivar Cabernet Sauvignon from the central region of Chile, in 2009 and 2010 vintages from two ripening points, were subjected to chemical and phenolic analyses, as were the wines made from these grapes. Grapes and the corresponding wines from three retail price wine categories, U.S. $6-8, U.S. $28-30, and U.S. $150-160, were evaluated. No differences were found across the price categories in the chemical analysis of grapes. Berry skins and wines from the higher price categories presented a higher concentration only of total tannins, and the differences in their concentrations were only among the different fractions of proanthocyanidins in the skins, seeds, and wines; there were no differences in their proportions. A seasonal effect influenced the concentrations of certain compounds in grapes and led to a decrease in the concentration of total phenols, total tannins, and total anthocyanins between sampling dates as harvesting moved toward the common commercial grape harvest in Chilean viticulture.  相似文献   

12.
To detect adulteration of wine, it has been proposed that the ratio of acetylated to p-coumaroylated conjugates of nine characteristic anthocyanins can be used to determine whether a wine is derived from Cabernet Sauvignon or hybrid grapes. If the ratio is >3, then a wine is classified as being derived from Cabernet Sauvignon grapes. This test has significant commercial implications as it is being used to decide whether Cabernet Sauvignon-labeled wines are genuine and can be imported into Germany. To assess whether this is a valid approach, 24 wines were analyzed, 4 of which were made from hybrids and 20 from Cabernet Sauvignon, with vintages ranging from 1993 to 2000. Only 13 of the Cabernet Sauvignon wines contained all nine of the "characteristic" anthocyanins, and the ratio of acetylated to p-coumaroylated derivatives varied from 1.2 to 6.5. It is evident that the use of the anthocyanin ratio method is flawed and that examination of the whole anthocyanin profile and/or investigation of the proportion of monoglucoside and acetylated anthocyanins is a better approach to distinguish between hybrid and Cabernet Sauvignon wines.  相似文献   

13.
The effect of oxygen on the levels of glutathione, an important antioxidant, in must and wine was studied using a novel LC-MSMS method for the analysis of reduced and oxidized glutathione. This study found that the storage of grape juice at high SO2 and ascorbic acid levels at -20 degrees C did not lead to a decrease in reduced glutathione levels. The effect of varying the oxygen levels in South African white grape juices, which included a reductive treatment (less than 0.3 mg/L dissolved O2 added), a control treatment (between 1.0 and 1.5 mg/L dissolved O2 added), and an oxidative treatment (3.5-4 mg/ L dissolved O2 added, without SO2) on reduced glutathione levels in the juice and resulting wine was also investigated. A custom build press was used to press whole bunches of two different Sauvignon Blanc and Colombard grapes. Alcoholic fermentation and oxygen additions to the must led to lower reduced glutathione levels in the wine. Reduced glutathione levels were only significantly higher in the wine made from reductive juice that had the highest initial reduced glutathione levels in the grapes.  相似文献   

14.
The enantiomeric distribution of 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (3MHA) in Vitis vinifera wines was determined by combining two techniques: specific purification of volatile thiols from the wines using p-hydroxymercuribenzoate and separation of the chiral molecules by gas-phase chromatography on a cyclodextrin capillary column. The R and S enantiomer ratios of these two thiols in dry white Sauvignon blanc and Semillon wines are approximately 30:70 for A3MH and 50:50 for 3MH. However, in sweet white wines made from grapes affected by "noble rot" due to the development of Botrytis cinerea on ripe grapes, the proportion of the R and S forms of 3MH is in the vicinity of 30:70. During alcoholic fermentation, a change in the ratio of the two enantiomers of 3MH in dry white wines was observed. At the beginning of fermentation (around density 1.08), the S form represented over 60%; then, at lower density, as fermentation proceeded, the enatiomeric ratio approached 50:50. The ratio of the two 3MHA enantiomers remained constant throughout fermentation. On the contrary, the distribution of the two 3MH enantiomers changed very little during fermentation of the botrytized sweet wines. The perception thresholds for the R and S forms of 3MH in hydroalcoholic model solution are similar (50 and 60 ng/L). These two enantiomers have quite different aromas: The R form is fruitier, with a zesty aroma reminiscent of grapefruit, while the S form smells more of passion fruit. The perception thresholds of the R and S enantiomers of 3MHA are slightly different (9 and 2.5 ng/L). The less odoriferous R form is reminiscent of passion fruit, while the S form has a more herbaceous odor of boxwood.  相似文献   

15.
Lower antioxidant activity in white wines in comparison to red wines lies in the low grape-skin-derived polyphenol content. This paper reports the analysis of the antioxidant capacities of white wine samples obtained along two different processing procedures directed to enrich the wine with polyphenols. White wine samples derived from whole squeezed grapes stored for increasing periods of time (up to 18 h) contained increasing concentrations of polyphenols (from 0.35 to 0.55 mmol/L) and, in parallel, exhibited increased capacity to scavenge free radicals and to inhibit copper ion-induced low-density lipoprotein (LDL) oxidation. However, addition of increasing concentrations of alcohol (up to 18%) to the whole squeezed grapes remarkably augmented the extraction of grape skin polyphenols into the wine up to 1.25 mmol/L, resulting in an increased capacity of the wine to scavenge free radicals and to inhibit LDL oxidation, to an extent similar to that of red wine. The extent of LDL oxidation inhibition was directly related to the wine polyphenolic content (r = 0.986). It is concluded that processing white wine by imposing a short period of grape skin contact in the presence of alcohol leads to extraction of grape skin polyphenols and produces polyphenol-rich white wine with antioxidant characteristics similar to those of red wine.  相似文献   

16.
Antioxidant capacity, as measured by oxygen radical absorbance capacity (ORAC(PE)), total phenolic, total and individual anthocyanins, and proanthocyanidin fraction contents were evaluated in red and white wines from grapes. A comparison in terms of antioxidant capacity is made with nontraditional wines made from highbush blueberry. Blueberries are among fruits that are best recognized for their potential health benefits. In red wines, total oligomeric proanthocyanidin content, including catechins, was substantially higher (177.18 +/- 96.06 mg/L) than that in white wines (8.75 +/- 4.53 mg/L). A relative high correlation in red wines was found between ORAC(PE) values and malvidin compounds (r = 0.75, P < 0.10), and proanthocyanidins (r = 0.87, P < 0.05). In white wines, a significant correlation was found between the trimeric proanthocyanidin fraction and peroxyl radical scavenging values (r = 0.86, P < 0.10). A moderate drink (1 drink per day, about 140 mL) of red wine, or white wine, or wine made from highbush blueberry corresponds to an intake of 2.04 +/- 0.81 mmol of TE, 0.47 +/- 0.15 mmol of TE, and 2.42 +/- 0.88 mmol of TE of ORAC(PE)/day, respectively.  相似文献   

17.
A sensitive and selective analytical method for the simultaneous separation and quantitative determination of proline and free monosaccharides in wine samples by high-performance anion-exchange chromatography coupled with pulsed amperometric detection is described. Under optimized experimental conditions, a complete separation was obtained in less than 30 min, using an isocratic elution with 10 mM NaOH and 1 mM Ba(OAc)(2). No postcolumn addition of strong bases to the eluent for enhancing detection sensitivity was needed. Upon 25-fold sample dilution and purification to avoid interference of tannins, pigments, and phenolic compounds, the fingerprinting of common monosaccharides (i.e., arabinose, glucose, fructose, galactose, and xylose) and proline in wines, musts, and vinegars can be easily accomplished. The method allows high recovery and satisfies the necessary requirements for accuracy, repeatability, and sensitivity. Values obtained for proline content ranged from 470 to 1190 mg/L in "Aglianico" red wines (mean value, 870 +/- 192 mg/L, n = 21) and from 168 to 286 mg/L in white wines (mean value, 208 +/- 32 mg/L, n = 11). Lower levels were found in musts of red and white grapes, 550 and 87 mg/L, respectively. The lowest content of proline, ca. 10 mg/L, was found both in white and red vinegars.  相似文献   

18.
The monomeric, oligomeric, and polymeric flavan-3-ol composition of wines, grape seeds, and skins from Vitis vinifera L. cv. Graciano, Tempranillo, and Cabernet Sauvignon has been studied using (1) fractionation by polyamide column chromatography followed by HPLC/ESI-MS analysis, (2) fractionation on C(18) Sep-Pak cartridges followed by reaction with vanillin and acid-catalyzed degradation in the presence of toluene-alpha-thiol (thiolysis). The content of monomers ((+)-catechin and (-)-epicatechin), procyanidin dimers (B3, B1, B4, and B2), trimers (T2 and C1), and dimer gallates (B2-3-O-gallate, B2-3'-O-gallate, and B1-3-O-gallate) ranged from 76.93 to 133.18 mg/L in wines, from 2.30 to 8.21 mg/g in grape seeds, and from 0.14 to 0.38 mg/g in grape skins. In wines, the polymeric fraction represented 77-84% of total flavan-3-ols and showed a mean degree of polymerization (mDP) value of 6.3-13.0. In grapes, the polymeric fraction represented 75-81% of total flavan-3-ols in seeds and 94-98% in skins and showed mDP values of 6.4-7.3 in seeds and 33.8-85.7 in skins. All the monomeric flavan-3-ols and oligomeric procyanidins found in wines were also present in seeds, although differences in their relative abundances were seen. The skin polymeric proanthocyanidins participated in the equilibration of the wine polymeric proanthocyanidin fraction, especially contributing to the polymer subunit composition and mDP.  相似文献   

19.
(1)H NMR spectroscopy was used to investigate the metabolic differences in wines produced from different grape varieties and different regions. A significant separation among wines from Campbell Early, Cabernet Sauvignon, and Shiraz grapes was observed using principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). The metabolites contributing to the separation were assigned to be 2,3-butanediol, lactate, acetate, proline, succinate, malate, glycerol, tartarate, glucose, and phenolic compounds by PCA and PLS-DA loading plots. Wines produced from Cabernet Sauvignon grapes harvested in the continental areas of Australia, France, and California were also separated. PLS-DA loading plots revealed that the level of proline in Californian Cabernet Sauvignon wines was higher than that in Australian and French Cabernet Sauvignon, Australian Shiraz, and Korean Campbell Early wines, showing that the chemical composition of the grape berries varies with the variety and growing area. This study highlights the applicability of NMR-based metabolomics with multivariate statistical data sets in determining wine quality and product origin.  相似文献   

20.
Dissipation of the fungicide spiroxamine in grapes of two vine varieties, Roditis and Cabernet Sauvignon, exposed to field treatments was evaluated. Vines of a grape vineyard located in central Greece were sprayed once or twice with a commercial formulation of the fungicide at 30 g a.i./hL. Residues in grapes, must, and wine were determined by gas chromatography/IT-MS after extraction with cyclohexane-dichloromethane (9:1), with a limit of quantitation 0.02 mg/kg in grapes and 0.012 mg/kg in wine. Under field conditions, spiroxamine dissipation on grapes was faster during the first 2 weeks and then slower to the sixth week. About 7 days after application, half of the initial spiroxamine concentration remained on the grapes; the respective proportion at 42 days was about 10%. At 14 and 35 days, residues were lower than 0.44 and 0.22 mg/kg, respectively, values below the maximum residue levels set by the European Union (1 mg/kg). Spiroxamine residues transferred from grapes into the must and through the vinification process into the wine were also studied. Mean transfer factors of 0.26 and 0.55 were found from grapes into wine for the wines obtained without maceration and with maceration, respectively. Residues in wine, prepared from grapes with a spiroxamine content of 0.11-0.20 mg/kg, varied from <0.026 to 0.09 mg/kg. Spiroxamine diastereomer B was found to dissipate slower than diastereomer A in the field as well as during the vinification process.  相似文献   

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