Phenolic compounds are important quality indicators of wine. Their composition in wine is determined by various factors, including grape variety, terroir, viticultural practices and oenological practices. There is very little extraction of colour compounds and, generally, very little phenolic content is expected and desired during traditional sparkling wine (TSW) vinification. Since phenolics are thought to reduce ageing capacity (Zoecklein, 2002), and are linked to browning in TSW (Ibern-Gomez et al., 2000), winemakers try to keep phenolic concentrations low throughout winemaking. This study investigated the effect of grape temperature at pressing on the phenolic extraction in Methode Cap Classique (MCC) wines and the evolution of the phenolics throughout winemaking. MCC wines were made by the traditional method over two vintages (2014 and 2015) using Chardonnay and Pinot Noir grapes harvested from two regions (Robertson and Darling) and stored at 0°C, 10°C, 25°C and 30°C. MCCs made from grapes stored at lower temperatures (0°C and 10°C) were found to have lower total phenolic content, colour intensity and total hydroxycinnamates than wines made from grapes stored at higher temperatures (25°C and 30°C). This shows that there was greater phenolic extraction at higher temperatures. No changes in the phenolic content were observed throughout winemaking.
酚类化合物是葡萄酒重要的品质指标。它们在葡萄酒中的成分是由各种因素决定的，包括葡萄品种、风土、葡萄栽培方法和酿酒方法。在传统的起泡酒(TSW)酿造过程中，很少提取颜色化合物，通常很少提取酚类物质。由于酚类物质被认为会降低陈酿能力(Zoecklein, 2002)，并与TSW中的褐变有关(Ibern-Gomez等人，2000)，酿酒师试图在整个酿酒过程中保持低浓度的酚类物质。本研究考察了葡萄压榨温度对经典法(method Cap Classique, MCC)葡萄酒中酚类物质提取的影响，以及酚类物质在酿酒过程中的演变。MCC葡萄酒采用传统方法在两个年份(2014年和2015年)中酿造，使用来自两个地区(罗伯逊和达令)的霞多丽和黑皮诺葡萄，并在0°C, 10°C, 25°C和30°C的温度下储存。用低温(0°C和10°C)储存的葡萄酿制的MCCs比高温(25°C和30°C)储存的葡萄酿制的葡萄酒具有更低的总酚含量、颜色强度和总羟基肉桂酸。这表明在较高的温度下，酚类物质的提取率较高。在整个酿酒过程中，没有观察到酚含量的变化。
{"title":"The Effect of Grape Temperature at Pressing on Phenolic Extraction and Evolution in Méthode Cap Classique Wines Throughout Winemaking","authors":"M. Mafata, A. Buica, W. D. Toit, F. Jaarsveld","doi":"10.21548/39-1-2621","DOIUrl":"https://doi.org/10.21548/39-1-2621","url":null,"abstract":"Phenolic compounds are important quality indicators of wine. Their composition in wine is determined by various factors, including grape variety, terroir, viticultural practices and oenological practices. There is very little extraction of colour compounds and, generally, very little phenolic content is expected and desired during traditional sparkling wine (TSW) vinification. Since phenolics are thought to reduce ageing capacity (Zoecklein, 2002), and are linked to browning in TSW (Ibern-Gomez et al., 2000), winemakers try to keep phenolic concentrations low throughout winemaking. This study investigated the effect of grape temperature at pressing on the phenolic extraction in Methode Cap Classique (MCC) wines and the evolution of the phenolics throughout winemaking. MCC wines were made by the traditional method over two vintages (2014 and 2015) using Chardonnay and Pinot Noir grapes harvested from two regions (Robertson and Darling) and stored at 0°C, 10°C, 25°C and 30°C. MCCs made from grapes stored at lower temperatures (0°C and 10°C) were found to have lower total phenolic content, colour intensity and total hydroxycinnamates than wines made from grapes stored at higher temperatures (25°C and 30°C). This shows that there was greater phenolic extraction at higher temperatures. No changes in the phenolic content were observed throughout winemaking.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"141-148"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-2621","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44077607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Chidi, M. Mafata, N. Z. Notshokovu, F. Jaarsveld
Maintaining the chemical composition of a wine is essential for the wine industry. Although the sugar-acid balance of a wine is of primary sensory importance, individual acids and oenological parameters are equally important. The main focus of this study was to investigate the impact of grape temperature at harvest, on the oenological volatile acidity (VA), titratable acidity (TA), pH and alcohol levels and organic acid (citric, malic, pyruvic and succinic) characteristics of Methode Cap Classique (MCC) wines during winemaking, produced from grape cultivars obtained from two regions. Chardonnay and Pinot noir grapes were obtained from Robertson (warmer) and Elgin (cooler) regions and were subjected to different temperature treatments, i.e. 0, 10, 25 and 30 o C before further processing, including pressing, primary fermentation, blending, tirage, secondary fermentation, riddling and disgorging. Grape temperature was mostly responsible for a significantly higher pH of Robertson (0 and 10oC) and lower pH (0oC) of Elgin post-tirage wines. Chardonnay base wines from both regions that were vinified from grapes at lower temperatures (0 and 10 o C) were richer in malic- and succinic acid, while Pinot noir wines from both regions were characterised by higher malic-, citric- and pyruvic acid. Pyruvic acid was only detected after the secondary fermentations in wines from both regions. To our knowledge, this study is the first to investigate the influence of grape temperature on the oenological and organic acid characteristics of MCC wines in different regions, and throughout different production stages.
保持葡萄酒的化学成分对葡萄酒工业至关重要。尽管葡萄酒的糖酸平衡具有首要的感官重要性，但单个酸和酿酒参数同样重要。本研究的主要重点是研究葡萄收获时的温度对两个地区的葡萄品种生产的Methode Cap Classique（MCC）葡萄酒在酿酒过程中的酿酒挥发性酸度（VA）、可滴定酸度（TA）、pH和酒精水平以及有机酸（柠檬酸、苹果酸、丙酮酸和琥珀酸）特性的影响。霞多丽和黑皮诺葡萄来自Robertson（温暖）和Elgin（凉爽）地区，在进一步加工之前，分别经过不同的温度处理，即0、10、25和30°C，包括压榨、一次发酵、混合、提拉奇、二次发酵、去壳和吐出。葡萄温度是Robertson葡萄酒pH值显著升高（0和10℃）和Elgin葡萄酒pH值较低（0℃）的主要原因。这两个地区的霞多丽基酒都是在较低的温度（0和10摄氏度）下用葡萄酿造的，其苹果酸和琥珀酸含量较高，而这两个区域的黑皮诺葡萄酒的特点是苹果酸、柠檬酸和丙酮酸含量较高。只有在两个地区的葡萄酒经过二次发酵后才检测到丙酮酸。据我们所知，本研究首次调查了不同地区和不同生产阶段葡萄温度对MCC葡萄酒的酿酒学和有机酸特性的影响。
{"title":"Impact of grape temperature at pressing on organic acids and oenological characteristics of Méthode Cap Classique wines","authors":"B. Chidi, M. Mafata, N. Z. Notshokovu, F. Jaarsveld","doi":"10.21548/39-1-2467","DOIUrl":"https://doi.org/10.21548/39-1-2467","url":null,"abstract":"Maintaining the chemical composition of a wine is essential for the wine industry. Although the sugar-acid balance of a wine is of primary sensory importance, individual acids and oenological parameters are equally important. The main focus of this study was to investigate the impact of grape temperature at harvest, on the oenological volatile acidity (VA), titratable acidity (TA), pH and alcohol levels and organic acid (citric, malic, pyruvic and succinic) characteristics of Methode Cap Classique (MCC) wines during winemaking, produced from grape cultivars obtained from two regions. Chardonnay and Pinot noir grapes were obtained from Robertson (warmer) and Elgin (cooler) regions and were subjected to different temperature treatments, i.e. 0, 10, 25 and 30 o C before further processing, including pressing, primary fermentation, blending, tirage, secondary fermentation, riddling and disgorging. Grape temperature was mostly responsible for a significantly higher pH of Robertson (0 and 10oC) and lower pH (0oC) of Elgin post-tirage wines. Chardonnay base wines from both regions that were vinified from grapes at lower temperatures (0 and 10 o C) were richer in malic- and succinic acid, while Pinot noir wines from both regions were characterised by higher malic-, citric- and pyruvic acid. Pyruvic acid was only detected after the secondary fermentations in wines from both regions. To our knowledge, this study is the first to investigate the influence of grape temperature on the oenological and organic acid characteristics of MCC wines in different regions, and throughout different production stages.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"106-115"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-2467","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47405408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Mafata, A. Buica, W. D. Toit, Valeria Panzeri, F. Jaarsveld
The production process of South African bottle-fermented sparkling wine, the Methode Cap Classique (MCC), follows the traditional French method (methode champenoise), although each cellar has its own unique additions to the method. South African winemakers use different techniques and blends to achieve their award-winning MCCs, but there have not been many scientific investigations of the science behind these wines. This project is one of the first scientific studies on MCC. MCC wines were made using Chardonnay and Pinot Noir grapes harvested over two vintages (2014 and 2015) from two regions (Robertson and Darling) and stored at 0°C, 10°C, 25°C and 30°C before processing. The study was aimed at investigating the effect of grape storage temperature on the sensory characteristics of MCCs. The aroma and taste of the final nine-month old MCCs were evaluated, with each region analysed separately. The study showed a grouping of the MCCs according to temperature treatments for both vintages. There were vintage differences in terms of the attributes cited and the frequency of citations. Based on the frequency of citation, the MCCs made 2014 from grapes stored at 0°C and 10°C were described by the judges as having a fruity, fresh and crisp aroma, whilst those made from grapes stored at 25°C and 30°C were described as having oxidised fruit, volatile acidity and solvent-like aromas. The judges perceived less oxidation and volatile acidity (VA) (in terms of the frequency of citation) in the aroma of the 2015 MCCs, although treatments at higher temperatures were still associated with less desirable attributes compared to treatments at lower temperature. This study shown that the temperature of the grape at the time of processing has a significant effect on the aroma of MCCs aged nine months, and not so much of an effect on the taste.
{"title":"The Effect of Grape Temperature on the Sensory Perception of Méthode Cap Classique Wines","authors":"M. Mafata, A. Buica, W. D. Toit, Valeria Panzeri, F. Jaarsveld","doi":"10.21548/39-1-2620","DOIUrl":"https://doi.org/10.21548/39-1-2620","url":null,"abstract":"The production process of South African bottle-fermented sparkling wine, the Methode Cap Classique (MCC), follows the traditional French method (methode champenoise), although each cellar has its own unique additions to the method. South African winemakers use different techniques and blends to achieve their award-winning MCCs, but there have not been many scientific investigations of the science behind these wines. This project is one of the first scientific studies on MCC. MCC wines were made using Chardonnay and Pinot Noir grapes harvested over two vintages (2014 and 2015) from two regions (Robertson and Darling) and stored at 0°C, 10°C, 25°C and 30°C before processing. The study was aimed at investigating the effect of grape storage temperature on the sensory characteristics of MCCs. The aroma and taste of the final nine-month old MCCs were evaluated, with each region analysed separately. The study showed a grouping of the MCCs according to temperature treatments for both vintages. There were vintage differences in terms of the attributes cited and the frequency of citations. Based on the frequency of citation, the MCCs made 2014 from grapes stored at 0°C and 10°C were described by the judges as having a fruity, fresh and crisp aroma, whilst those made from grapes stored at 25°C and 30°C were described as having oxidised fruit, volatile acidity and solvent-like aromas. The judges perceived less oxidation and volatile acidity (VA) (in terms of the frequency of citation) in the aroma of the 2015 MCCs, although treatments at higher temperatures were still associated with less desirable attributes compared to treatments at lower temperature. This study shown that the temperature of the grape at the time of processing has a significant effect on the aroma of MCCs aged nine months, and not so much of an effect on the taste.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"132-140"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-2620","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47112875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Simone, G. Montevecchi, F. Masino, S. Imazio, C. Bignami, A. Antonelli
Malvasia odorosissima is an aromatic grapevine (Vitis vinifera L., 1753) variety that is often confused with Malvasia di Candia aromatica (Vitis vinifera L., 1753), despite the genetic information now available on the pedigree and genetic relationships linking the two varieties. In an effort to offer a contribution to fill this gap, also from an aromatic point of view, free and glycosylated aroma compounds were determined using the SPE extraction method, followed by GC-MS analysis in two consecutive vintages. The results have for the first time provided the aromatic characterisation of Malvasia odorosissima. Geraniol and its derivatives were the most abundant set of volatiles. In contrast to Malvasia di Candia aromatica and the other aromatic varieties, Malvasia odorosissima showed a very small amount of glycosylated volatiles, thus expressing its aromatic potential almost completely. The abundance of free terpenoids in the aromatic profile of Malvasia odorosissima, even higher than in Malvasia di Candia aromatica, is a main feature for the oenological exploitation of this variety, which is on the brink of extinction. In addition, the presence of rose oxides, found solely in Malvasia odorosissima, renders its aromatic profile more similar to that of White Muscat. This result is consistent with the parent-offspring relationship linking the two varieties that was recently ascertained.
Malvasia odorosissima是一种芳香葡萄品种(Vitis vinifera L.， 1753)，经常与Malvasia di Candia aromatica (Vitis vinifera L.， 1753)混淆，尽管现在有关于两个品种的系谱和遗传关系的遗传信息。为了填补这一空白，也从芳香的角度出发，用SPE萃取法测定了游离和糖基化的芳香化合物，然后用GC-MS分析了两个连续的年份。这一结果首次提供了马来香的芳香特征。香叶醇及其衍生物是最丰富的挥发物。与甘蔗渣和其他芳香品种相比，臭甘蔗渣的糖基化挥发物含量极低，几乎完全表达了其芳香潜力。Malvasia odorosissima芳香谱中游离萜类化合物的丰度甚至高于Malvasia di Candia aromatica，这是该濒临灭绝品种酿酒开发的主要特征。此外，玫瑰氧化物的存在，只在Malvasia odorosissima中发现，使其芳香剖面更类似于白色马斯喀特。这一结果与最近确定的两个品种的亲代关系是一致的。
{"title":"Aromatic characterisation of Malvasia odorosissima grapevines and comparison with Malvasia di Candia aromatica","authors":"G. Simone, G. Montevecchi, F. Masino, S. Imazio, C. Bignami, A. Antonelli","doi":"10.21548/39-1-2458","DOIUrl":"https://doi.org/10.21548/39-1-2458","url":null,"abstract":"Malvasia odorosissima is an aromatic grapevine (Vitis vinifera L., 1753) variety that is often confused with Malvasia di Candia aromatica (Vitis vinifera L., 1753), despite the genetic information now available on the pedigree and genetic relationships linking the two varieties. In an effort to offer a contribution to fill this gap, also from an aromatic point of view, free and glycosylated aroma compounds were determined using the SPE extraction method, followed by GC-MS analysis in two consecutive vintages. The results have for the first time provided the aromatic characterisation of Malvasia odorosissima. Geraniol and its derivatives were the most abundant set of volatiles. In contrast to Malvasia di Candia aromatica and the other aromatic varieties, Malvasia odorosissima showed a very small amount of glycosylated volatiles, thus expressing its aromatic potential almost completely. The abundance of free terpenoids in the aromatic profile of Malvasia odorosissima, even higher than in Malvasia di Candia aromatica, is a main feature for the oenological exploitation of this variety, which is on the brink of extinction. In addition, the presence of rose oxides, found solely in Malvasia odorosissima, renders its aromatic profile more similar to that of White Muscat. This result is consistent with the parent-offspring relationship linking the two varieties that was recently ascertained.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"77-88"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-2458","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43779344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. S. Espíndola, J. A. Camargo, E. Pringles, M. Battistella
Raisin grapes are potentially more profitable than wine grapes in San Juan, Argentina, although the traditional system of grape drying requires an extensive use of costly labour. Production costs might be reduced by adopting the dry-on-vine (DOV) raisin-making system, but the feasibility of DOV in Argentina has not been assessed, and neither have the costs and pruning schemes. Thus we determined drying time and yields, estimated wages per hectare, and determined the influence of pruning severity on Flame Seedless raisin grapes. A completely random design with six treatments and six replicates was used in the 2013 to 2016 seasons. The treatments comprised differences in the nodes per cane, nodes per vine, distribution of nodes, and sugar content. Descriptive statistics and variance analysis were calculated for fresh fruit weight, dry fruit weight, drying ratio and drying time. The leaf area and its relationship with dried fruit weight also were calculated. These data were processed with the Infostat program. The DOV system demands between 11 and 31 additional days during the drying period and reduces labour costs by between 38% and 64% compared to the traditional system. Long pruning with the same load of buds is better. Furthermore, the DOV system is not associated with a lower production and thus appears to be a financially sustainable alternative to traditional production systems for Flame Seedless raisin grape producers in Argentina.
{"title":"Effect of Pruning Severity on Yield, Drying Time and Wages in Flame Seedless Dry-on-vine and Traditional Raisin Production Systems in Argentina","authors":"R. S. Espíndola, J. A. Camargo, E. Pringles, M. Battistella","doi":"10.21548/39-1-1549","DOIUrl":"https://doi.org/10.21548/39-1-1549","url":null,"abstract":"Raisin grapes are potentially more profitable than wine grapes in San Juan, Argentina, although the traditional system of grape drying requires an extensive use of costly labour. Production costs might be reduced by adopting the dry-on-vine (DOV) raisin-making system, but the feasibility of DOV in Argentina has not been assessed, and neither have the costs and pruning schemes. Thus we determined drying time and yields, estimated wages per hectare, and determined the influence of pruning severity on Flame Seedless raisin grapes. A completely random design with six treatments and six replicates was used in the 2013 to 2016 seasons. The treatments comprised differences in the nodes per cane, nodes per vine, distribution of nodes, and sugar content. Descriptive statistics and variance analysis were calculated for fresh fruit weight, dry fruit weight, drying ratio and drying time. The leaf area and its relationship with dried fruit weight also were calculated. These data were processed with the Infostat program. The DOV system demands between 11 and 31 additional days during the drying period and reduces labour costs by between 38% and 64% compared to the traditional system. Long pruning with the same load of buds is better. Furthermore, the DOV system is not associated with a lower production and thus appears to be a financially sustainable alternative to traditional production systems for Flame Seedless raisin grape producers in Argentina.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"21-26"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-1549","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49161208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cultivar identification by ampelography is often difficult and is sensitive to environmental conditions, thus it can be problematic to distinguish between closely related cultivars. DNA fingerprinting offers an alternative method that is not influenced by the environment and is relatively easy to perform. However, discriminating between closely related individuals can be problematic if inadequate or insufficient markers are used. Following the estimation of null allele frequencies, an initial set of 35 microsatellite markers was reduced to 20 to generate unique DNA fingerprints for the majority of 111 different grape cultivars and breeding lines. Molecular evidence was utilised to evaluate the accuracy of the reported pedigrees for several cultivars bred in South Africa (SA). The use of markers linked to known downy mildew and powdery mildew resistance loci (Rpv3 and Ren3) provided information regarding the frequency of these resistance loci in the breeding material analysed.
{"title":"Microsatellite-based DNA fingerprinting of selected grapevine cultivars","authors":"C. V. Heerden, P. Burger, R. Prins","doi":"10.21548/39-1-2053","DOIUrl":"https://doi.org/10.21548/39-1-2053","url":null,"abstract":"Cultivar identification by ampelography is often difficult and is sensitive to environmental conditions, thus it can be problematic to distinguish between closely related cultivars. DNA fingerprinting offers an alternative method that is not influenced by the environment and is relatively easy to perform. However, discriminating between closely related individuals can be problematic if inadequate or insufficient markers are used. Following the estimation of null allele frequencies, an initial set of 35 microsatellite markers was reduced to 20 to generate unique DNA fingerprints for the majority of 111 different grape cultivars and breeding lines. Molecular evidence was utilised to evaluate the accuracy of the reported pedigrees for several cultivars bred in South Africa (SA). The use of markers linked to known downy mildew and powdery mildew resistance loci (Rpv3 and Ren3) provided information regarding the frequency of these resistance loci in the breeding material analysed.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"58-66"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-2053","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41782365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
development of Cabernet Sauvignon grapes during two consecutive seasons (2011 to 2012) in the northwest of China was evaluated. The applied training systems include the modified vertical shoot positioned (M-VSP); the fan training system with two trunks (F-TT); and the fan training system with multiple trunks (F-MT). The results show that the pattern of flavan-3-ol accumulation was similar for the three training systems in both vintages, with flavan-3-ols being the highest around veraison, before declining as harvest approaches. Compared to the 2011 vintage, the dry vintage of 2012 had a greater accumulation of total flavan-3-ols and individual flavan-3-ol monomers, including (+)-catechin (C), (-)-epicatechin (EC) and (-)-epicatechin-3-O-gallate (ECG). With regard to the effect of training systems, M-VSP contributed to a significantly higher content of total flavan-3-ols, while the percentage of ECG was lower for M-VSP. As for the three flavan-3-ol units (terminal subunits, extension subunits and monomers), the 2012 vintage was more likely to accumulate extension subunits and monomers, and the effect of training system on these three flavan-3-ols units varied between the different vintages. Meanwhile, the proportion of ECG in terminal subunits and of C in extension subunits was higher in 2012, whereas the training system of F-TT had a higher percentage of ECG in extension subunits in both vintages. In addition, the effect of vintage on the composition of flavan-3-ols in harvested grape seeds was more obvious than that of the training system.
{"title":"Effect of Training Systems on Accumulation of Flavan-3-ols in Cabernet Sauvignon Grape Seeds at the North Foot of Mt. Tianshan","authors":"Yunjun Liu, J. Yan, Qiang Li, J. Wang, Ying Shi","doi":"10.21548/39-1-1579","DOIUrl":"https://doi.org/10.21548/39-1-1579","url":null,"abstract":"development of Cabernet Sauvignon grapes during two consecutive seasons (2011 to 2012) in the northwest of China was evaluated. The applied training systems include the modified vertical shoot positioned (M-VSP); the fan training system with two trunks (F-TT); and the fan training system with multiple trunks (F-MT). The results show that the pattern of flavan-3-ol accumulation was similar for the three training systems in both vintages, with flavan-3-ols being the highest around veraison, before declining as harvest approaches. Compared to the 2011 vintage, the dry vintage of 2012 had a greater accumulation of total flavan-3-ols and individual flavan-3-ol monomers, including (+)-catechin (C), (-)-epicatechin (EC) and (-)-epicatechin-3-O-gallate (ECG). With regard to the effect of training systems, M-VSP contributed to a significantly higher content of total flavan-3-ols, while the percentage of ECG was lower for M-VSP. As for the three flavan-3-ol units (terminal subunits, extension subunits and monomers), the 2012 vintage was more likely to accumulate extension subunits and monomers, and the effect of training system on these three flavan-3-ols units varied between the different vintages. Meanwhile, the proportion of ECG in terminal subunits and of C in extension subunits was higher in 2012, whereas the training system of F-TT had a higher percentage of ECG in extension subunits in both vintages. In addition, the effect of vintage on the composition of flavan-3-ols in harvested grape seeds was more obvious than that of the training system.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"35-46"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-1579","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44067694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anthocyanins and tannins are very important chemical compounds in the grape berry and the corresponding wine, as they greatly influence the colour, taste and maturation potential of the wine, as well as offer numerous health benefits. This review tries to establish the origin of anthocyanins and tannins by looking at metabolic pathways and attempting to establish a link between photosynthesis and the flavonoid biosynthetic pathway, the translocation thereof from leaves to berries, different methods to extract anthocyanins and tannins from wine and, in the end, the different analytical methods that can be used to analyse for anthocyanins and tannins.
{"title":"Tannins and Anthocyanins: From Their Origin to Wine Analysis – A Review","authors":"A. Nel","doi":"10.21548/39-1-1503","DOIUrl":"https://doi.org/10.21548/39-1-1503","url":null,"abstract":"Anthocyanins and tannins are very important chemical compounds in the grape berry and the corresponding wine, as they greatly influence the colour, taste and maturation potential of the wine, as well as offer numerous health benefits. This review tries to establish the origin of anthocyanins and tannins by looking at metabolic pathways and attempting to establish a link between photosynthesis and the flavonoid biosynthetic pathway, the translocation thereof from leaves to berries, different methods to extract anthocyanins and tannins from wine and, in the end, the different analytical methods that can be used to analyse for anthocyanins and tannins.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"1-20"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-1503","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48453620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Maturano, M. C. Nally, M. Assof, M. Toro, L. Figueroa, V. Jofré, F. Vazquez
The free aromatic composition of must from Pedro Gimenez grapes, grown in San Juan, Argentina, was characterised. Samples from the vintages of 2008 and 2009 were analysed by gas chromatography–mass spectrometry–solid phase microextraction (GC–MS–SPME). Higher alcohols, terpenes, C13-norisoprenoids, esters, aldehydes and ketones were quantified. The calculation of the odour activity values (OAVs) revealed that β-damascenone, α-ionone, β-linalool, geraniol, ethyl butanoate, hexanoate and octanoate were the most prevalent aroma-active compounds of the grape variety. However, the remaining 42 aromatic compounds that registered OAVs less than 1 could potentially contribute to the flavour of Pedro Gimenez grapes. The measured monoterpene levels indicate that the Pedro Gimenez grape can be considered a neutral variety. This is the first report describing the main potential free aroma contributors of Pedro Gimenez grapes in two consecutive years.
{"title":"Free Volatile Compounds of cv. Pedro Giménez (Vitis vinifera L.) White Grape Must Grown in San Juan, Argentina","authors":"Y. Maturano, M. C. Nally, M. Assof, M. Toro, L. Figueroa, V. Jofré, F. Vazquez","doi":"10.21548/39-1-1565","DOIUrl":"https://doi.org/10.21548/39-1-1565","url":null,"abstract":"The free aromatic composition of must from Pedro Gimenez grapes, grown in San Juan, Argentina, was characterised. Samples from the vintages of 2008 and 2009 were analysed by gas chromatography–mass spectrometry–solid phase microextraction (GC–MS–SPME). Higher alcohols, terpenes, C13-norisoprenoids, esters, aldehydes and ketones were quantified. The calculation of the odour activity values (OAVs) revealed that β-damascenone, α-ionone, β-linalool, geraniol, ethyl butanoate, hexanoate and octanoate were the most prevalent aroma-active compounds of the grape variety. However, the remaining 42 aromatic compounds that registered OAVs less than 1 could potentially contribute to the flavour of Pedro Gimenez grapes. The measured monoterpene levels indicate that the Pedro Gimenez grape can be considered a neutral variety. This is the first report describing the main potential free aroma contributors of Pedro Gimenez grapes in two consecutive years.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"27-34"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48726940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Kuchen, F. Vazquez, M. Mestre, M. Toro, Y. Maturano
The pre-fermentative cold soak (CS) is proposed so as to extract and stabilise polyphenolic compounds in wines. CS is applied empirically to Cabernet Sauvignon in Cuyo, Argentina; however, there is poor scientific background on this technique. The aim was analyse the effect of cold soak time on colour parameters such as total polyphenols, total anthocyanins, tannins, colour and polymerisation indexes. Moreover, Saccharomyces and non-Saccharomyces populations were studied to evaluate their impact on colour. Cabernet Sauvignon must (Pedernal, San Juan) was distributed into four vessels: CONTROL (CT): simultaneous maceration and alcoholic fermentation (AF) with commercial yeast D254; T1: CS for two days; T2: CS for five days; and T3: CS for seven days. T1, T2 and T3 were maintained at 4 ± 1°C during CS. They were later inoculated with D254 (AF: 22 ± 1°C). The total polyphenol index (TPI), total anthocyanins (TA) and tannins were quantified during CS and AF. The colour index (CI) and polymerisation index (PI) were determined at the end of AF. The total yeast populations of Saccharomyces and non-Saccharomyces were quantified during CS and AF. The highest values of TA, tannins, TPI and PI were obtained by CT. This treatment also registered the highest total yeast population and the highest total yeast death. The highest CI was observed in T3. When Saccharomyces was found at the end of CS (T1 and T2), it dominated the alcoholic fermentation in the early stages (not observed in CT and T3). The use of the pre-fermentative CS technique in Cabernet Sauvignon wines is promising for young wines due to the increased colour obtained.
{"title":"Influence of Cold Maceration Time on Chromatic and Microbiological Characteristics of Cabernet Sauvignon Wines","authors":"B. Kuchen, F. Vazquez, M. Mestre, M. Toro, Y. Maturano","doi":"10.21548/39-1-2460","DOIUrl":"https://doi.org/10.21548/39-1-2460","url":null,"abstract":"The pre-fermentative cold soak (CS) is proposed so as to extract and stabilise polyphenolic compounds in wines. CS is applied empirically to Cabernet Sauvignon in Cuyo, Argentina; however, there is poor scientific background on this technique. The aim was analyse the effect of cold soak time on colour parameters such as total polyphenols, total anthocyanins, tannins, colour and polymerisation indexes. Moreover, Saccharomyces and non-Saccharomyces populations were studied to evaluate their impact on colour. Cabernet Sauvignon must (Pedernal, San Juan) was distributed into four vessels: CONTROL (CT): simultaneous maceration and alcoholic fermentation (AF) with commercial yeast D254; T1: CS for two days; T2: CS for five days; and T3: CS for seven days. T1, T2 and T3 were maintained at 4 ± 1°C during CS. They were later inoculated with D254 (AF: 22 ± 1°C). The total polyphenol index (TPI), total anthocyanins (TA) and tannins were quantified during CS and AF. The colour index (CI) and polymerisation index (PI) were determined at the end of AF. The total yeast populations of Saccharomyces and non-Saccharomyces were quantified during CS and AF. The highest values of TA, tannins, TPI and PI were obtained by CT. This treatment also registered the highest total yeast population and the highest total yeast death. The highest CI was observed in T3. When Saccharomyces was found at the end of CS (T1 and T2), it dominated the alcoholic fermentation in the early stages (not observed in CT and T3). The use of the pre-fermentative CS technique in Cabernet Sauvignon wines is promising for young wines due to the increased colour obtained.","PeriodicalId":21894,"journal":{"name":"South African Journal of Enology and Viticulture","volume":"39 1","pages":"89-99"},"PeriodicalIF":1.3,"publicationDate":"2018-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.21548/39-1-2460","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47802246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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