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1.
以栽培于广西地区2 个圆叶葡萄品种‘Noble’和‘Carlos’为实验材料,以真葡萄品种‘赤霞珠’和‘雷司令’为对照,使用超高效液相色谱-串联三重四极杆飞行时间质谱,分析其种子发育过程中多酚组成和积累特性。结果表明:在4种葡萄发育过程的种子样品中共检测到106种多酚,包括48种鞣花酸及前体物、24种黄酮醇、20种羟基苯甲酸、9种黄烷-3-醇、3种芪类和2种羟基肉桂酸。鞣花酸及前体物(主要是前体物)和黄烷-3-醇(主要是没食子酰化体和单体)分别是圆叶葡萄和真葡萄种子中最主要的多酚类型,但其含量在不同年份和品种间具有较大差异。前体物含量在圆叶葡萄‘Noble’幼果期种子中较高,然后逐渐下降,完全转色后再次上升;‘Carlos’则在浆果转色前种子中含量较高,随后略有下降。黄烷-3-醇在真葡萄‘雷司令’种子中2013年随着浆果发育含量显著升高,转色时含量达到最高,随后有所下降,2014年不受发育期的影响;‘赤霞珠’则分别在2013年幼果期和2014年果实完熟时的种子中含量最高。 相似文献
2.
The effects of exogenous abscisic acid (ABA) on phenolic characteristics of grapes and wines were investigated in Vitis vinifera cvs. Merlot and Cabernet Sauvignon. Exogenous ABA treatment at veraison significantly improved phenolic contents, mainly anthocyanins and flavonols, and antioxidant properties of the grape skins, but had no effects on total phenolics and antioxidant activities in the seeds or on basic fruit qualities. The wines made from ABA-treated grapes were also consequently enhanced in total phenolics, anthocyanins, flavonols and antioxidant activities. The proportions of methylated anthocyanins in the skins and acylated anthocyanins and derived pigments in the wines were decreased to some degree by exogenous ABA treatment. No distinct relationships were observed between ABA concentrations and phenolic characteristics, and the effects were observed even with 200 mg/L ABA. The results revealed that exogenous ABA applied at veraison offered opportunities to improve phenolic contents and nutritional values of grape skins and wines. 相似文献
3.
Changes of the polyphenolic content, including total phenolics (TP), total flavonoids (TF), and total flavan-3-ols (TF3-ols) determined by spectrophotometric methods, have been studied in Macedonian white wines from Vitis vinifera L. cv, Smederevka and Chardonnay, obtained under different vinifications and analyzed during 16 months of aging in bottles. Winemaking treatments for both varieties included an addition of two doses of SO2 (50 and 100 mg/L) and two commercial yeasts for fermentation, Vinalco and Levuline, both Saccharomyces cerevisiae species, in order to study the influence of SO2 and yeasts on the phenolic content of the wines. Comparing the two varieties, Chardonnay wines contained higher levels of total phenolics, flavonoids, and flavan-3-ols, probably as a result of the cultivar differences. Sulfur dioxide protected the phenolic oxidation, resulting in higher phenolic content in the wines with higher SO2 dose, while the yeast did not show significant influence on the total phenolics. During aging, the TP, TF, and TF3-ols in the wines from both varieties decreased significantly up to the second month of storage and remained stable till the sixth month. The Student–Newman–Keuls test has been applied to ascertain possible significant differences between the studied wines, and a principal component analysis has been employed, showing separation and grouping of the wines according to the cultivar and time of aging. 相似文献
4.
以天津蓟州区栽培的"美乐"和"赤霞珠"葡萄为试验品种,分别在其始熟期的初、中和末期3个阶段利用外源脱落酸(200 mg/L)处理果实,采用分光光度法测定葡萄和葡萄酒中酚类总含量和抗氧化活性,利用液质联用技术分析花色苷的含量和组成.研究结果表明:始熟期的外源脱落酸处理对成熟果实的质量、可溶性固形物、可滴定酸和pH值,以及葡萄籽的酚类含量和抗氧化活性没有显著影响,但对葡萄皮和葡萄酒的酚类物质含量和活性具有显著影响.在始熟期中期(30% ~50%果实转色)以前,对果实喷施外源脱落酸可以显著提高葡萄皮和葡萄酒的酚类总含量、花色苷总含量和抗氧化活性.始熟期外源脱落酸处理使"美乐"和"赤霞珠"果实的酚类总含量分别提高了14% ~39%和73% ~172%,花色苷总含量和抗氧化活性分别提高了18% ~143%和88% ~178%;外源脱落酸处理使葡萄酒的3个指标(酚类总含量、花色苷总含量和抗氧化活性)分别提高了17% ~69%、18% ~36%和21% ~46%,而这些影响可以有效改善葡萄酒的感官品质和营养价值.外源脱落酸处理时期的精准控制可以提高酿酒葡萄及葡萄酒中酚类物质含量及抗氧化作用,进而提高葡萄酒品质和营养价值. 相似文献
5.
Cabernet-Sauvignon and Merlot skin and seed extracts from Bordeaux grapes were investigated to determine both grape variety and vintage effect on phenolic composition. The total content of polyphenols and tannins in Merlot seeds was higher than that of Cabernet-Sauvignon allowing to discriminate the varieties. HPLC analyses underlined significant differences in the absolute concentration of proanthocyanidins amongst the two varieties and in their composition: mean degree of polymerisation (mDP) and percentage of galloylation of seed extracts were good indicators of grape variety. The vintage effect on the phenolic composition was confirmed for 2009 in comparison to previous vintages. Low values of mDP and concentrations of proanthocyanidins and anthocyanins were found in 2009 seeds and skins. The climatic conditions of 2009 (high rainfall before flowering followed by a strong hydric stress during berries development until ripening) let us hypothesise a lower activation of flavonoid pathway. 相似文献
6.
利用高效液相色谱-质谱联用(HPLC-MS)技术研究西拉葡萄果实成熟过程中果皮内非花色苷酚类物质的变化.结果表明:在葡萄成熟过程中共检测到27种非花色苷酚类物质,其中黄酮醇类物质舍量最高,黄烷-3-醇类次之.各类非花色苷酚类的含量在转色开始逐渐上升,到转色后1~2周达到最大值,随后缓慢下降;采摘前2周,除了酚酸类物质含量趋于稳定、白藜芦醇含量下降之外,其它非花色苷酚类物质含量再次升高. 相似文献
7.
Analysis of tannins in seeds and skins of Shiraz grapes throughout berry development 总被引:2,自引:0,他引:2
MARK O. DOWNEY JOHN S. HARVEY SIMON P. ROBINSON 《Australian Journal of Grape and Wine Research》2003,9(1):15-27
The flavan-3-ol and proanthocyanidin composition of both seeds and skin of Vitis vinifera L. cv. Shiraz grapes was determined by reversed-phase HPLC after acetone extraction and acid-catalysis in the presence of excess phloroglucinol. Samples were taken at weekly intervals from fruit-set until commercial harvest. The main period of proanthocyanidin accumulation in grape seeds occurred immediately after fruit-set with maximum levels observed around veraison. Over two seasons there was variation in both the timing and content of proanthocyanidins in seeds. In skin, proanthocyanidin accumulation occurred from fruit set until 1–2 weeks after veraison. Proanthocyanidin subunit composition was different in seeds and skin and changed during berry development but the mean degree of polymerisation of the tannin polymers in skins was higher than in the seeds at all stages of berry development. Proanthocyanidin levels in both seeds and skin decreased between veraison and harvest. Additional proanthocyanidin subunits were released when the residues remaining after acetone extraction were subjected to direct acid-catalysis in the presence of phloroglucinol. In the seeds, these accounted for much of the post-veraison decrease, but not in grape skin. At harvest, 75% of extractable berry proanthocyanidin was in the seeds. Accumulation of proanthocyanidins in the seeds appears to be independent of that in the skins, but in both tissues synthesis occurs early in berry development and maximum levels are reached around veraison. 相似文献
8.
Violeta Ivanova Ágnes Dörnyei László Márk Borimir Vojnoski Trajće Stafilov Marina Stefova Ferenc Kilár 《Food chemistry》2011
Macedonian Vranec wines were analysed by HPLC coupled with DAD and MS detections and by spectrophotometric methods. ESI-IT MS and MS–MS methods with alternating ionisation polarity were used for identification of the phenolic compounds. Both, nonflavonoids (stilbens, hydroxybenzoic and hydroxycinnamic acids and derivatives) and flavonoids (flavonols, flavan-3-ols and anthocyanins) were detected in the samples. Vranec wines were produced under different fermentation conditions: maceration time of 3, 6 and 10 days, two doses of SO2 (30 and 70 mg l−1) and two yeasts for fermentation, in order to examine their effects on the extraction of phenolic compounds from grapes into the wine. 相似文献
9.
Milan N. Mitić Jean-Marc Souquet Mirjana V. Obradović Snežana S. Mitić 《Food science and biotechnology》2012,21(6):1619-1626
Three table grapes and 4 wine grapes collected from a southern Serbian vineyard were evaluated and compared for their antioxidant properties and phenolic profile. Among the varieties tested, ‘Cabernet Sauvignon’ contained the highest total phenolic content with 173.6 mg/100 g of fresh weight. Also, the total flavonoid and antocyanin content of ‘Cabernet Sauvignon’ was significantly higher from the other. ‘Cabernet Sauvignon’ and ‘Merlot’ had the strongest DPPH· radicals scavenging activity (1,318.6 and 1,282.0 μmol Trolox equivalent/100 g, respectively). ‘Cabernet Sauvignon’, ‘Merlot’, ‘Prokupac’, ‘Vranac’, ‘Muscat Hamburg’, and ‘Ribier’ grape varieties were found to be rich in malvidin-3-O-glucoside, while ‘Cardinal’ grape variety was found to be rich in peonidin-3-O-glucoside. The following compounds were also identified and quantified using HPLC-DAD: 2 flavan-3-ols and 4 hydroxycinnamic acids in all grape samples. The results suggested that phytochemicals in the selected table and wine grapes have potent antioxidant activities in correlation with phenolic content. 相似文献
10.
The effect of bunch shading on berry development and flavonoid accumulation in Shiraz grapes 总被引:2,自引:1,他引:2
MARK O. DOWNEY JOHN S. HARVEY SIMON P. ROBINSON 《Australian Journal of Grape and Wine Research》2004,10(1):55-73
Opaque boxes were applied to bunches of Shiraz grapes prior to flowering to determine the effect of sunlight on berry development and accumulation of flavonoids. The boxes were designed to maintain airflow while excluding light and thus to minimise changes in temperature and humidity. There was no significant effect of shading on sugar accumulation and in two of the three seasons studied there was no effect on berry weight. Chlorophyll concentration was much lower in the shaded fruit, which appeared pale yellow until veraison. The fruit coloured normally in the shaded bunches and in two of the three seasons there was no significant change in anthocyanin content. Expression of the gene encoding UDP-glucose flavonoid-3-O-glucosyl transferase (UFGT), a key gene in anthocyanin synthesis, increased after veraison and was similar in both shaded and exposed fruit. Anthocyanin composition was altered in the shaded fruit, which had a greater proportion of the dioxygenated anthocyanins, the glucosides of cyanidin and peonidin. Shading had no significant effect on the levels of condensed tannins in the skin or seeds of ripe fruit. Shading significantly reduced the levels of flavonols in the grape skin. In the exposed fruit, flavonol concentration was highest around flowering then declined as the berries grew, but there was an increase in flavonols per berry during ripening. When the boxes were applied before flowering, shaded fruit had much lower levels of flavonols throughout berry development and at harvest the level of flavonols were less than 10% of that in exposed fruit. A gene encoding flavonol synthase (FLS) was expressed at flowering and during ripening in exposed grapes but its expression was greatly reduced in shaded fruit. The results indicate that shading had little effect on berry development and ripening, including accumulation of anthocyanins and tannins, but significantly decreased flavonol synthesis. 相似文献
11.
Synthesis of flavonols and expression of flavonol synthase genes in the developing grape berries of Shiraz and Chardonnay (Vitis vinifera L.) 总被引:1,自引:0,他引:1
MARK O. DOWNEY JOHN S. HARVEY SIMON P. ROBINSON 《Australian Journal of Grape and Wine Research》2003,9(2):110-121
Flavonols were determined in Shiraz and Chardonnay grapes throughout berry development. The predominant flavonols were quercetin-3-glycosides with trace amounts of kaempferol-3-glycosides detected in Shiraz flowers but not in developing berries. Flavonols were present in the skin of ripening grapes but were not detected in seeds or flesh. Flavonols were also present in buds, tendrils, inflorescences, anthers and leaves. The concentration of flavonols in flowers (mg/g fresh weight) was high and decreased between flowering and berry set then remained relatively constant through berry development. The total amount of flavonols in berries (mg/berry) was low until pre-veraison then increased during berry development, particularly before veraison, the onset of ripening, in Chardonnay and during ripening in Shiraz. Two cDNA fragments with homology to genes encoding the enzyme flavonol synthase (FLS) were isolated from Shiraz flowers. In the overlapping region of the two cDNAs, they had 80% sequence identity at the nucleotide level and both had high homology to FLS genes from other plants. VvFLS1 was expressed in leaves, tendrils, pedicels, buds and inflorescences as well as in developing grapes. Expression was highest between flowering and fruit set then declined, increasing again during ripening coincident with the increase in flavonols per berry. Expression of VvFLS2 was much lower than for VvFLS1 and did not change during berry development. The results indicate that two distinct periods of flavonol synthesis occur in grapes, the first around flowering and the second during ripening of the developing berries. 相似文献
12.
E. BOIDO M. GARCÍA‐MARINO E. DELLACASSA F. CARRAU J.C. RIVAS‐GONZALO M.T. ESCRIBANO‐BAILÓN 《Australian Journal of Grape and Wine Research》2011,17(3):383-393
Background and Aims: Changes in different polyphenol families during grape ripening and vinification were determined in Tannat grapes. This was done to establish a polyphenol profile for Tannat grapes during ripening and for young wines. Methods and Results: We demonstrated, by high‐performance liquid chromatography with diode array detection and mass spectrometry (HPLC‐DAD‐MS) analysis, that the content of flavan‐3‐ols in Tannat seeds was higher than that reported for a large number of other grape varieties analysed. Forty per cent of the total flavan‐3‐ols in seeds were galloylated compounds, whereas the flavan‐3‐ol profile in skins was characterised by the absence of galloylated forms. Prodelphinidins in skins ranged between 30 and 35% with very low values for epigallocatechin. Epicatechin gallate was not detected in Tannat wine and galloylated forms represented a low percentage of total flavan‐3‐ols. Tannat grapes had very high concentrations of anthocyanins in skins with levels increasing during ripening. Eleven phenolic acids were identified in Tannat grape skins and wines, but only gallic and protocatechuic acids were found in the seeds. Conclusions: Tannat wines were shown to have one of the highest levels of phenolic compounds reported for vinifera grape varieties. The profiles for different polyphenol families present in Tannat grapes (skins and seeds) and wines were determined. Significance of the Study: The results presented will help to better understand the phenolic winemaking potential of this variety and its functional properties within food chemistry. 相似文献
13.
Ana Ortega‐Regules Inmaculada Romero‐Cascales Jose M Lpez‐Roca Jose M Ros‐García Encarna Gmez‐Plaza 《Journal of the science of food and agriculture》2006,86(10):1460-1467
The anthocyanin content and fingerprint of four different Vitis vinifera L. varieties (Cabernet Sauvignon, Merlot, Syrah and Monastrell), the last grown in two different locations, were studied during three growing seasons to determine how seasonal conditions and location affect the content of berry anthocyanins and their relative percentages. Important differences in the content of anthocyanins were detected among varieties—Monastrell grapes from one of the locations presenting the highest anthocyanin content—when expressed as µg g?1 of skin. However, due to the large berry size of Monastrell grapes, when the results were expressed as mg kg?1 of berry, Cabernet Sauvignon and Syrah grapes presented the highest concentration. Significant differences were found as regards growing season, the concentration of anthocyanins being lowest in 2003, the warmest year. As regards the relative percentage of the different anthocyanins, substantial differences were found between varieties, but again, the results were also influenced by the year under study. When the percentages of anthocyanins were used as variables in a discriminant analysis, a 100% correct classification of the four different varieties was obtained. Moreover, to check the suitability of this tool for classifying varieties, data referring to the anthocyanin percentages of the four varieties grown in very different agroecological conditions and at different ripening stages were tested with the model we have built, 89% of correct classification being achieved. Copyright © 2006 Society of Chemical Industry 相似文献
14.
Sergio Navarro Maela León Luis Roca-Pérez Rafael Boluda Lorenzo García-Ferriz Pedro Pérez-Bermúdez Isabel Gavidia 《Food chemistry》2008
We present characterisation data for two Spanish autochthonous grapevines, Bobal and Crujidera, in comparison with the well-known cultivars Tempranillo and Cabernet Sauvignon. Microsatellite markers were used for the molecular characterisation of Crujidera grapevines. Leaf macronutrient contents of the four cultivars were evaluated, as well as their changes at different vine developmental stages, and veraison was seen as the most suitable time to evaluate the nutritional status. Quantitative changes in some physiological parameters and the phenolic composition of the four grape varieties were measured during the last month of ripening. Polyphenols, tannins and anthocyanins increased with grape maturation, although the accumulation of these phenolic compounds and their patterns of evolution varied considerably with the cultivar. The biosynthetic potential of these grapes to produce resveratrol largely depended on the grape variety, with a remarkably high content found in Bobal berry skins. 相似文献
15.
三种红色酿酒葡萄品种果实酚类物质比较 总被引:1,自引:0,他引:1
为了综合评价酿酒葡萄品种特性,以酿酒葡萄美乐、品丽珠、赤霞珠为研究对象,采用比色法测定果实不同部位酚类物质含量,并对结果进行主成分分析。结果表明,赤霞珠葡萄果皮中总酚、单宁、黄烷醇、花色苷含量分别为28.82 mg/g、23.15 mg/g、41.19 mg/g、9.25 mg/g,均显著高于美乐和品丽珠(P<0.05);赤霞珠葡萄种子中总酚、单宁、总类黄酮分别为14.56 mg/g、5.74 mg/g、2.32 mg/g,显著高于品丽珠(P<0.05)。主成分分析结果表明,赤霞珠葡萄酚类物质在第一主成分和第二主成分综合得分为82.27分,为酚类物质含量丰富的品种。 相似文献
16.
Crupi P Coletta A Anna Milella R Perniola R Gasparro M Genghi R Antonacci D 《Journal of food science》2012,77(2):C174-C181
Flavonoids present in skin extracts of red seedless table grape varieties Summer Royal, Autumn Royal, and Crimson, and white seedless varieties Carati and Thompson were analyzed by HPLC-DAD-MS, in 3 y of study (2006 to 2008). The anthocyanins, delphinidin-3-O-glucoside, cyanidin-3-O-glucoside, petunidin-3-O-glucoside (with their corresponding p-coumaroyl derivatives), peonidin-3-O-glucoside, and malvidin-3-O-glucoside (with their corresponding acetyl, caffeoyl, and p-coumaroyl derivatives) were found. In addition the flavonols quercetin-3-O-glucuronide, quercetin-3-O-rutinoside, quercetin-3-O-glucoside, kaempferol-3-O-glucoside, kaempferol-3-O-galactoside, and the flavan-3-ols procyanidin B1, procyanidin B2, and catechin were also detected. Anthocyanins were the main flavonoids in red grapes ranging from 24 (Crimson) to 500 (Summer Royal) mg/kg fresh weight of grapes; consistent levels of flavonols and flavan-3-ols were also quantified in all varieties. To determine the effective climatic influence on flavonoids content in field conditions, viticultural practices have been developed, that could exclude the effects of direct solar radiation from confounding the assessment of those related to thermal conditions alone. A strong positive correlation was determined between flavonoids and temperature data that seem to be responsible for the difference of these metabolites along the years; furthermore, it has been possible to define a linear relationship (R(2) = 0.6871, P = 0.0057) between thermal amplitude and total flavonoids values in the red grapes. PRACTICAL APPLICATION: Grapes are economically the most important fruit species in the world and approximately 30% of its production is used as fresh fruit. Because of the very important role of flavonoids in food quality as well as their health-promoting properties, and considering that our experiments were performed along 3 consecutive years, gathered results in this research are quite promising to give a useful information on the flavonoid contents and their evolution in 5 seedless table grapes that are widespread in Mediterranean regions but also in California and South America, and are grown in a viticultural climate (Apulia, South Italy) very close to some regions of Spain, Turkey, Tunisia, and Israel. 相似文献
17.
果实粒径对‘美乐’和‘蛇龙珠’葡萄果实品质的影响 总被引:2,自引:0,他引:2
果实粒径普遍被认为是影响果实品质的一项重要指标。本实验以宁夏玉泉营地区的‘美乐’和‘蛇龙珠’葡萄为实验材料,将‘美乐’果粒分为大于14 mm(大果粒)、12~14 mm(中等果粒)、小于12 mm(小果粒)3 个粒径等级;将‘蛇龙珠’果粒分为大于15 mm(大果粒)、14~15 mm(中等果粒)、小于14 mm(小果粒)3 个粒径等级,连续两年测定不同粒径葡萄的可溶性固形物质量分数、可滴定酸质量浓度、花色苷单体含量以及单体酚含量。结果表明:连续两年两个葡萄品种均表现为中等果粒所占比例较高;2014年‘美乐’和‘蛇龙珠’葡萄果实的可溶性固形物质量分数随粒径的增大而降低,而2015年均表现为中等果粒较高;连续两年葡萄的种/果质量比和单果粒种子数均随粒径的减小而降低;2014、2015年酚类物质含量在‘美乐’中表现为小果粒和中等果粒较高,‘蛇龙珠’则为大果粒和中等果粒较高;‘美乐’中等果粒葡萄的花色苷单体总量最高,‘蛇龙珠’果实的花色苷单体含量受年份影响较大;单体酚总量以及黄酮醇类物质总量在‘美乐’葡萄中表现为在中等果粒中较高,‘蛇龙珠’葡萄则表现为在大果粒中较高。结论:中等果粒的‘美乐’葡萄和大果粒的‘蛇龙珠’葡萄酚类物质含量较高。 相似文献
18.
Chamber drying under controlled temperature and humidity conditions of the red grape varieties Merlot and Tempranillo grown in Andalusia (Spain), and the fortification and maceration of the musts in the presence of skin from both types of grapes, to obtain sweet red wines, has been studied. Changes in colour and in monomeric and polymeric phenols during the vinification process were examined. Chamber drying increased the sugar content to about 31.4 °Brix within 48 h in Merlot grapes and 72 h in Tempranillo grapes. This drying process also causes skin rupture, facilitating the access of phenolic compounds to the pulp. The resulting musts exhibited slight browning and increased red hues, due to a high concentration of anthocyanins; maceration in the presence of grape skins for 24 h provided the best results. The end-product contained highly acceptable tannin, colour and phenolic compounds for marketing as a high quality sweet red wine, in comparison with other commercial sweet red wines. 相似文献
19.
Maja Dimitrovska Mirjana Bocevska Darko Dimitrovski Michael Murkovic 《European Food Research and Technology》2011,232(4):591-600
The anthocyanin composition of red grape varieties Vranec, Cabernet Sauvignon, Merlot and Pinot Noir was determined analyzing
the skin extracts of the grape berries. The relative content of the identified anthocyanins was calculated and the obtained
anthocyanic profiles were compared in terms of acylation and anthocyanidin distribution. The predominant anthocyanin in all
varieties was malvidin-3-glucoside ranging from 35.8% in Cabernet Sauvignon to 67.1% in Pinot Noir. Vranec variety was characterized
by high proportions of coumaroyl derivatives (22%) and peonidins (13%). The most pronounced difference among the studied grape
cultivars was the relative amount of acetate derivatives accounting 35% in Cabernet Sauvignon, 22% in Merlot and 9% in Vranec.
Different relationships among the anthocyanin groups of compounds were calculated and considered as parameters for differentiation
of the cultivars. The relationship between coumarates and acetates in Vranec was significantly higher compared with Merlot
and Cabernet Sauvignon with obtained values of 2.37 versus 0.63 and 0.56, respectively. Moreover, the ratio between delphinidins
and peonidins allows clear discrimination between the studied grape cultivars showing the greatest difference. 相似文献
20.
Renee T. Threlfall Justin R. Morris Luke R. Howard Cindi R. Brownmiller Teresa L. Walker 《Journal of food science》2005,70(3):S167-S171
ABSTRACT: The effects of hot and cold (nonheated) pressing on yield, quality components, and nutraceutical content of juice, grapes, and press fractions (seeds and skins) from Black Beauty ( Vitis rotundifolia ) and Sunbelt ( Vitis labruscana L.) grape cultivars were evaluated. Heating the must before pressing increased juice yield, titratable acidity, red color, brown/yellow pigments, and darkness and decreased the press fraction yield and juice pH in both cultivars. Sunbelt juice from the heated must had the highest yield (786 L/metric ton), red color, brown/yellow pigments, and darkness. Black Beauty nonheated must had the largest press fraction (43%) but the lowest red color, brown/yellow pigments, and darkness in the juice. The juice generally had less total phenolics, total anthocyanins, and oxygen radical absorbance capacity (ORAC) than the whole grapes. The juice from heated Black Beauty and Sunbelt musts had the highest total phenolics (1354 and 1937 mg/L, respectively) and anthocyanins (414 and 513 mg/L, respectively). Although the data for seeds and skins are on a dry basis, the press fractions had higher levels of phenolics and ORAC than the whole grapes and juice. The dried seeds had more phenolics and less anthocyanins than the skins. The highest total phenolic level (95338 mg/kg) equivalents and ORAC level (1100 μmol trolox/g) was in Black Beauty seeds from nonheated must. The skins of nonheated Sunbelt had the highest anthocyanins (11889 mg/kg). Because the press fractions of both cultivars had high ORAC values and total phenolic levels, products with nutraceutical benefits could be developed. 相似文献