Article

Sensory attributes of Cabernet Sauvignon wines made from vines with different water status

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Abstract

The dependence of wine sensory properties on vine water status in Vitis vinifera L., cv. Cabernet Sauvignon was tested. Cabernet Sauvignon vines in the Napa Valley were subjected to three drip irrigation treatments: minimal irrigation (no irrigation added unless the midday leaf water potential dropped below –1.6 MPa), standard irrigation (32 L water/vine/week), and double irrigation (64 L water/vine/week). The minimal irrigation treatment produced midday leaf water potentials that were significantly lower than the other treatments throughout the season. Mean grape yields varied from 15.0 to 21.7 t/ha. Descriptive analysis conducted on the resulting wines demonstrated significant differences in several sensory attributes as per analysis of variance of the ratings. Analysis of variance and principal component analysis showed that the wines made from the minimal irrigation treatment were significantly higher in red/blackberry aroma, jam/cooked berry aroma, dried fruit/raisin aroma, and fruit by mouth than the wines from the irrigated treatments. The standard irrigation treatment wines were rated significantly higher than the minimal irrigation treatment wines in vegetal aroma, bell pepper aroma, black pepper aroma, and astringency. We conclude that vine water deficits lead to wines with more fruity and less vegetal aromas and flavours than vines with high vine water status.

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... Deficit irrigation decreases IBMP content in wines (Chapman et al., 2005;Mendez-Costabel et al., 2014). However, this effect may be, indirect because of an increased bunch shading in fully irrigated vines which are generally more vigorous. ...
... Ageing bouquet typicity was significantly correlated to δ 13 C (Figure 1). Another study found water deficit increased fruity characters in wine and reduced green flavours (Chapman et al., 2005). In this study, the increased fruity character in deficit irrigated vines was attributed to esters, although no aroma compounds were measured. ...
... The wines produced from vines which undergo water deficit, may present a reduction in green aromas (Cabernet-Sauvignon, Merlot, Sauvignon blanc) and contain less (-)-rotundone (Syrah). It is not well established if this effect is direct, or indirect, as mediated by lower vigour and more exposed fruit to sunlight (Chapman et al., 2005;Mendez-Costabel et al., 2014). Wines from water deficit vines are more fruity (Chapman et al., 2005) and contain more C 13 -norisoprenoids (Koundouras et al., 2006;Bindon et al., 2007). ...
Article
Terroir is about the link between wine and its origin. It has long been understood by sensory evaluation that the taste of wine from a given variety can be related to its origins. Specific organoleptic characteristics of wine are influenced by environmental factors such as soil and climate. By deconstructing the effect of measurable soil and climate parameters on grape and wine aroma compounds, the terroir effect on wine typicity can be better understood. Climate influences on vine development and grape ripening are mainly associated with temperature, radiation and rainfall, while soil influences are primarily associated with water availability and nitrogen supply. Significant advances have been made over recent years in understanding wine aromas and their molecular basis and influences of climate and soil on a wide range of molecules responsible for wine aroma expression. This article aims to review these recent research advances to obtain a more comprehensive understanding of how terroir influences wine typicity. The effect of terroir on wine quality and typicity is sometimes considered intangible and difficult to explain on a scientific basis. By combining agronomic, analytical and sensory approaches, however, this review shows that the terroir effect is mediated by measurable factors that can easily be monitored in the vineyard. Assessment of the results compiled by this review allows the suggestion that terroir expression at specific sites might be maximized by choosing appropriate plant material in relation to soil and climate, by acting on manageable parameters like vine water and nitrogen status, or by implementing canopy management to modify microclimate in the bunch zone.
... Moreover, the results displayed in Table 2 indicate that irrigation can be used for modulating wine volatile composition even in a sub-humid region such as Ribeiro, as previously reported for drier climates [33,35]. The previous reports on the effect of irrigation on wine volatile composition offered contrasting results depending on grapevine variety, soil type, climate conditions, and severity and time of occurrence of water stress [12,32,35,[37][38][39]. For instance, Talaverano et al. [39] reported higher concentrations of alcohols, C6 compounds, and volatile phenols in Tempranillo wines from rain-fed vines. ...
... The previous research on white varieties under cool-humid climate conditions showed that aroma descriptors differed according to vine water status [42]. Usually, higher marks have been reported for wines coming from vines suffering from a low-to-moderate water deficit [13,42], although this depended on the grapevine variety, the region of cultivation, and the intensity of the water deficit, as reported for Cabernet Sauvignon [37], Chardonnay [7], Merlot [43], and Riesling [42]. In agreement with these reports, Albariño wines from the rain-fed treatment received significantly higher marks for white and fresh fruit descriptors than wines from the irrigated treatment in the current study (Fig. 2), this reflects the fact that irrigation can be used for modulating fruity notes in wine [44]. ...
... In agreement with these reports, Albariño wines from the rain-fed treatment received significantly higher marks for white and fresh fruit descriptors than wines from the irrigated treatment in the current study (Fig. 2), this reflects the fact that irrigation can be used for modulating fruity notes in wine [44]. In contrast, the absence of water stress induced wines with vegetal character, supporting previous research [37,42,45]. ...
Article
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Volatile composition plays a fundamental role in wine aroma and quality. However, the concentrations of volatiles depend on climate conditions and agricultural practices, such as irrigation. The aim of the current study was to assess the effects of irrigation on the volatile composition and sensory characteristics of wines from Vitis vinifera (L.) cultivar ‘Albariño’ in two zones of NW Spain (Rías Baixas and Ribeiro) during three consecutive years (2012, 2013, and 2014). Irrigation was scheduled by the vine grower in Rías Baixas, whereas it was fixed at 50% of the estimated crop evapotranspiration in Ribeiro. Water was applied in August, mainly, in Rías Baixas and from mid-July to mid-August in Ribeiro. Irrigation significantly altered the concentrations of several volatiles, which differed between zones and years. For instance, wines from the irrigated treatment had lower concentrations of isoamyl acetate, 2-phenylethyl acetate, and ethyl hexanoate than those from the rain-fed treatment in Rías Baixas. In contrast, irrigation increased the concentrations of ethyl hexanoate and ethyl octanoate, while reduced those of free terpenes in wines from Ribeiro. Mainly, these differences between zones were caused by the climate conditions of each region.
... Differences were found in terms of appearance, aroma, flavor, and taste among irrigation treatments. Through use of descriptive analysis, Cabernet sauvignon wines produced from vines of higher water status were determined to have more vegetal and less fruity aromas and flavors than vines with lower water status (Chapman et al., 2005). ...
... Many sensory differences were consistent over many vineyards while some other attributes were site specific or insignificant. The results support other studies that show the dependence of wine sensory attributes on vine water status (Chapman et al., 2005;Matthews et al., 1990). ...
... The more fruit forward wines were those of lower leaf ψ zones (< -1.0 MPa). This is consistent with studies involving red wine cultivars (Chapman et al., 2005;Hakimi and Reynolds, 2010;Ledderhof et al., 2014) and Noble et al. (1995) who found more fruit-driven wines from soils with less water holding capacity and lower water status. Treatments resulting in higher vine water status and soils with more available water produced more vegetative wines. ...
Article
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Aims: Determinants of the terroir effect in Riesling were sought by choosing vine water status as a major factor. It was hypothesized that consistent water status zones could be identified within vineyards, and, differences in wine sensory attributes could be related to vine water status.Methods and results: To test our hypothesis, 10 Riesling vineyards representative of each Ontario Vintners Quality Alliance sub-appellation were selected. Vineyards were delineated using global positioning systems and 75 to 80 sentinel vines were geo-referenced within a sampling grid for data collection. During 2005 to 2007, vine water status measurements [leaf water potential (ψ)] were collected bi-weekly from a subset of these sentinel vines. Vines were categorized into “low” and “high” leaf ψ zones within each vineyard through use of geospatial maps and replicate wines were made from each zone. Wines from similar leaf ψ zones had comparable sensory properties ascertained through sorting tasks and multidimensional scaling (2005, 2006). Descriptive analysis further indicated that water status affected wine sensory profiles, and attributes differed for wines from discrete leaf ψ zones. Multivariate analyses associated specific sensory attributes with wines of different leaf ψ zones. Several attributes differed between leaf ψ zones within multiple vineyard sites despite different growing seasons. Wines produced from vines with leaf ψ >-1.0 MPa had highest vegetal aromas whereas those with leaf ψ <-1.3 MPa were highest in honey, petrol and tropical fruit flavors. Vines under mild water deficit had highest honey, mineral, and petrol and lowest vegetal aromas.Conclusion: Results indicate that water status has a profound impact on sensory characteristics of Riesling wines and that there may be a quality threshold for optimum water status.Significance and impact of the study: These data suggest that vine water status has a substantial impact on the sensory properties of Riesling wines. Variability of leaf ψ within vineyards can lead to wines that differ in their sensory profiles. These findings were consistent among vineyards across the Niagara Peninsula. These strong relationships between leaf ψ and sensory attributes of Riesling suggest that vine water status is a major basis for the terroir effect.
... A great research effort has been devoted to assess the effects of grapevine water status on berry and wine composition, mainly on red varieties under semi-arid environments [39][40][41][42][43][44][45], although recent studies dealt with white varieties [46][47][48]. In general, these studies proved that the timing and intensity of water deficits affected the magnitude of the changes in berry metabolism and in wine color, aroma, and flavor by altering berry size and/or the synthesis of berry compounds. ...
... The beneficial effects of RDI on grapevine can be summarized in (1) improvement of water-use efficiency; (2) reduction of heat stress; and/or (3) delay of grape ripening. Most of the research effort has been focused on red varieties, such as Cabernet Sauvignon, Syrah, Merlot, or Tempranillo [40,41,44,178]. These studies provided contrasting results depending on the grapevine variety considered and local conditions. ...
Article
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Water availability is endangering the production, quality, and economic viability of growing wine grapes worldwide. Climate change projections reveal warming and drying trends for the upcoming decades, constraining the sustainability of viticulture. In this context, a great research effort over the last years has been devoted to understanding the effects of water stress on grapevine performance. Moreover, irrigation scheduling and other management practices have been tested in order to alleviate the deleterious effects of water stress on wine production. The current manuscript provides a comprehensive overview of the advances in the research on optimizing water management in vineyards, including the use of novel technologies (modeling, remote sensing). In addition, methods for assessing vine water status are summarized. Moreover, the manuscript will focus on the interactions between grapevine water status and biotic stressors. Finally, future perspectives for research are provided. These include the performance of multifactorial studies accounting for the interrelations between water availability and other stressors, the development of a cost-effective and easy-to-use tool for assessing vine water status, and the study of less-known cultivars under different soil and climate conditions.
... Several authors have reported the effect of vine water status on grape and wine volatile compounds (Koundouras et al. 2006, Bindon et al. 2007, Qian et al. 2009, Song et al. 2012, Talaverano et al. 2016, Bouzas-Cid et al. 2018. Two studies suggested that, when compared with the standard irrigation of grapevines, deficit irrigation alters several sensory attributes of wine as well as the concentration of the carotenoids and their derivatives in the berries (Chapman et al. 2005, Bindon et al. 2007). Chapman et al. (2005) showed that water deficit influences the physiological parameters of the vine, changes the berry composition, and improves the sensory attributes of wine by increasing fruity aromas and decreasing vegetal aromas, while Bindon et al. (2007) observed that deficit irrigation increased the concentration of some C 13 -norisoprenoids such as β-damascenone and β-ionone in Cabernet Sauvignon grape berries at harvest. ...
... Two studies suggested that, when compared with the standard irrigation of grapevines, deficit irrigation alters several sensory attributes of wine as well as the concentration of the carotenoids and their derivatives in the berries (Chapman et al. 2005, Bindon et al. 2007). Chapman et al. (2005) showed that water deficit influences the physiological parameters of the vine, changes the berry composition, and improves the sensory attributes of wine by increasing fruity aromas and decreasing vegetal aromas, while Bindon et al. (2007) observed that deficit irrigation increased the concentration of some C 13 -norisoprenoids such as β-damascenone and β-ionone in Cabernet Sauvignon grape berries at harvest. ...
Article
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Background and Aims Available soil water is an important factor determining grapevine yield and grape composition. The aim of this study was to determine the impact of water availability on the yield components and the composition of must and wine of Vitis vinifera L. cv. Verdejo. Methods and Results The irrigation strategies [rainfed (R0), drip irrigated at 25% ETo (R25) and 50% ETo (R50) applied weekly from the end of the vegetative main shoot growth until harvest] were imposed on white Verdejo grapevines over three consecutive seasons (2012–2014). The 50% ETo treatment resulted in the highest yield. Increasing water availability also reduced the concentration of volatile phenols in all seasons, and of the C6 compounds in 2014 alone. The highest concentration of five individual volatile compounds was associated with the lowest water availability (R0). Conclusions High water availability increased yield and its components, mainly in the wettest season. Volatile compounds in wine were modified by water regime, with their concentration increased by the most severe deficit irrigation regime (R0). The effect of the year on must and wine composition was greater than the in‐season effects of water availability treatment. Significance of the Study This study has described the effect of soil water availability on yield and its components and the composition of must and wine of Verdejo.
... The higher intensity of fruit aroma and palate attributes in these wines may reflect the higher LAI : yield ratio for these rootstocks. They could also be indicative of a stress effect, however, since in a study involving Cabernet Sauvignon treated with minimal irrigation compared with standard or double irrigation treatments, the wine from the minimal irrigation treatment was significantly higher in red/blackberry aroma and fruit by mouth than the wines from the standard and double irrigation treatments (Chapman et al. 2005). The must TSS from the minimal irrigation treatment in that study was lower (24.1 Brix) than that for the other treatments (25.3 Brix) (Chapman et al. 2005), which further indicates that higher intensity of fruit aroma and on the palate was due to the imposed water stress rather than being linked with riper fruit having higher TSS. ...
... They could also be indicative of a stress effect, however, since in a study involving Cabernet Sauvignon treated with minimal irrigation compared with standard or double irrigation treatments, the wine from the minimal irrigation treatment was significantly higher in red/blackberry aroma and fruit by mouth than the wines from the standard and double irrigation treatments (Chapman et al. 2005). The must TSS from the minimal irrigation treatment in that study was lower (24.1 Brix) than that for the other treatments (25.3 Brix) (Chapman et al. 2005), which further indicates that higher intensity of fruit aroma and on the palate was due to the imposed water stress rather than being linked with riper fruit having higher TSS. In our study, it was notable that for 2013 wines, when controlling for differences in alcohol concentration, some of the significant rootstock effects on sensory attributes were no longer significant. ...
Article
Background and Aims The study compared the viticultural performance and wine sensory attributes of Shiraz grafted on eight rootstocks with a range in vine vigour and grown under drip‐irrigation with moderately saline water. Methods and Results The rootstocks were 140 Ruggeri, 1103 Paulsen, 110 Richter, Ramsey, 101‐14, M5489, M5512 and M6262. Ramsey and 140 Ruggeri had the highest leaf area index and M6262 the lowest. Ramsey had highest yield, followed by 140 Ruggeri > M5489 = 110 Richter > M5512 > 1103 Paulsen = 101‐14 > M6262. Rootstock M6262 had highest wine chloride concentration of 482 and 384 mg/L in 2012 and 2013, respectively, but salty taste and a thickness mouthfeel (viscosity) were significant only in 2012. Wines from the other seven rootstocks had a chloride and sodium concentration under 175 and 40 mg/L, respectively. Colour density was highest in wine from 101‐14 in 2012 and from 101‐14, 1103 Paulsen and M5489 in 2013. A salt tolerance index (STI) for the eight rootstocks was calculated based on yield, leaf area index, grape juice chloride and sodium concentration and wine colour density. Conclusions Rootstock M6262 had lowest STI in both years. M5489 had highest STI in 2013 followed by 110 Richter = M5512 = 101‐14 = 140 Ruggeri. The recognition threshold for salty taste may lie between a chloride concentration in wine of between 384 and 482 mg/L. Significance of the Study The STI, based on five wine grape performance parameters, provides a promising measure of rootstock salt tolerance compared with the traditional parameters of yield and/or capacity for salt exclusion.
... In this way, ETo is related to deficit irrigation, and the influence of elicitation on grape berry aromas has been little studied (Chaves et al., 2010). Thus, Chapman, Roby, Ebeler, Guinard, and Matthews (2005) reported that water deficits in grapevines led to wine with fruitier and less vegetal aromas than those from vines with high water status, in Cabernet Sauvignon variety. These results may match with the observed during the third studied season of the present work, in relation that some terpenoids, C 13 norisoprenoids, esters and benzenoids were improved after MeJ application, while certain C6 compounds decreased by this treatment in grape berries. ...
... These results may match with the observed during the third studied season of the present work, in relation that some terpenoids, C 13 norisoprenoids, esters and benzenoids were improved after MeJ application, while certain C6 compounds decreased by this treatment in grape berries. Chapman et al. (2005) reported that water deficits may have led to a greater flux of carbon through alternative biosynthetic pathways leading to an increase in amino acids (precursors of esters in wines) and in carotenoids (precursors of C 13 norisoprenoids), resulting in a fruitier aroma. Moreover, Bindon, Dry, and Loveys (2007) observed that the deficit irrigation improved the concentration of hydrolytically released C 13 norisoprenoids (β-damascenone, β-ionone and TDN) in Cabernet Sauvignon grape berries at harvest. ...
Article
An alternative to improve grape quality is the elicitor application to the vineyard due its implication to induce defense mechanisms involved in the synthesis of secondary metabolites. There are few studies about the influence of elicitors on grape volatile composition. The aim of this work was to investigate the influence of methyl jasmonate (MeJ) foliar application to Tempranillo grapevines on grape aroma composition over three consecutive vintages. In the first vintage, MeJ treatment improved p-cymene, methyl jasmonate, and hexanal synthesis, and degraded 2-hexen-1-ol acetate, (Z)-3-hexen-1-ol, and n-hexanol. In the second season, the content of several terpenes, β-damascenone, methyl jasmonate, esters, benzenoids and (Z)-3-hexen-1-ol was diminished after MeJ application. In the third vintage, the synthesis of several volatile compounds considered positive contributors for grape aroma was improved by MeJ application. In conclusion, the effect of MeJ foliar application on grape volatile content was mainly dependent on the vintage.
... Several authors have reported the effect of vine water status on grape and wine volatile compounds (Koundouras et al. 2006, Bindon et al. 2007, Qian et al. 2009, Song et al. 2012, Talaverano et al. 2016, Bouzas-Cid et al. 2018. Two studies suggested that, when compared with the standard irrigation of grapevines, deficit irrigation alters several sensory attributes of wine as well as the concentration of the carotenoids and their derivatives in the berries (Chapman et al. 2005, Bindon et al. 2007). Chapman et al. (2005) showed that water deficit influences the physiological parameters of the vine, changes the berry composition, and improves the sensory attributes of wine by increasing fruity aromas and decreasing vegetal aromas, while Bindon et al. (2007) observed that deficit irrigation increased the concentration of some C 13 -norisoprenoids such as β-damascenone and β-ionone in Cabernet Sauvignon grape berries at harvest. ...
... Two studies suggested that, when compared with the standard irrigation of grapevines, deficit irrigation alters several sensory attributes of wine as well as the concentration of the carotenoids and their derivatives in the berries (Chapman et al. 2005, Bindon et al. 2007). Chapman et al. (2005) showed that water deficit influences the physiological parameters of the vine, changes the berry composition, and improves the sensory attributes of wine by increasing fruity aromas and decreasing vegetal aromas, while Bindon et al. (2007) observed that deficit irrigation increased the concentration of some C 13 -norisoprenoids such as β-damascenone and β-ionone in Cabernet Sauvignon grape berries at harvest. ...
Conference Paper
El estado hídrico del viñedo ha sido reconocido como un factor importante que determina la calidad de la uva. El objetivo de este estudio fue conocer el impacto de la disponibilidad del agua la composición volátil de los vinos Verdejo. Las estrategias de riego (secano [R0], riego por goteo al 25 % ETo [R25] y 50 % ETo [R50] aplicadas semanalmente desde el final de la brotación hasta la vendimia), se realizaron en un viñedo de la variedad Verdejo durante tres años consecutivos. Los resultados mostraron que la composición volátil fue modificada por el régimen hídrico aumentando su concentración en el régimen de riego deficitario (R0). El año mostró un mayor efecto que el régimen hídrico sobe la composición del mosto y la composición volátil de los vinos. Este estudio reveló los efectos de las condiciones del agua sobre la composición volátil del vino de cv. Verdejo.
... This defective odor is related to higher IBMP levels originating from grapes and entering wines [24]. Wines made from grapes treated with minimal irrigation are rated significantly lower in terms of vegetal and bell-pepper aroma than those from grapes irrigated under standard conditions [99]. Stress induced by a combination of lateral shoot removal and water deficit (T-3) was conducted to detect the changes in VvOMT. ...
Article
Full-text available
3-Alkyl-2-methoxypyrazines (MPs) contribute to the herbaceous flavor characteristics of wine and are generally considered associated with poor-quality wine. To control the MPs in grapes and wine, an accurate understanding of MP metabolism is needed. This review covers factors affecting people in the perception of MPs. Also, the history of O-methyltransferases is revisited, and the present review discusses the MP biosynthesis, degradation, and biochemical regulation. We propose the existence of a cycle between MPs and 3-alkyl-2-hydropyrazines (HPs), which proceeds via O-(de)methylation steps. This cycle governs the MP contents of wines, which make the cycle the key participant in MP regulation by genes, environmental stimuli, and microbes. In conclusion, a comprehensive metabolic pathway on which the HP–MP cycle is centered is proposed after gaining insight into their metabolism and regulation. Some directions for future studies on MPs are also proposed in this paper.
... C 6 -Alcohols are responsible, to some extent, for the green herbaceous and vegetable aromas in wines, which is a negative quality attribute (González-Barreiro et al., 2015). The correlations between LWP and C 6 -alcohols are in agreement with sensory evaluation of Baconoir (Balint and Reynolds, 2017), Pinot noir (Ledderhof et al., 2014) and Cabernet sauvignon (Chapman et al., 2005) wines, suggesting that vines with higher water status were associated to more herbaceous and vegetal wines. Several studies have documented that irrigation regimes based on different reference evapotranspiration (ET o ) levels modified the vegetal and herbaceous character of wines. ...
Article
Water deficit and iron nutritional deficiency (iron chlorosis) are frequent environmental stresses affecting grapevine production in the Mediterranean area. The objectives of this work were (i) to study the combined effects of both stresses on aromatic profile of Tempranillo grapes, when they act simultaneously in the vineyard, and (ii) to evaluate the feasibility of foliar chlorophyll content at veraison (Chl) to early assess aromatic quality potential of grapes in those conditions. Twenty non-irrigated vineyard subzones (10 m x 10 m each), affected and non-affected by iron chlorosis, were monitored in Ribera del Duero Appellation of Origin (North-Central Spain) during two consecutive seasons. Factorial ANOVA was performed to study the effects of predawn leaf water potential and Chl, both measured at veraison on the must composition parameters and, specifically, on the concentrations of free and bound aromatic compounds in the musts. Water deficit tended to increase color intensity and extractable anthocyanin content of the grapes, whereas the incidence of iron deficiency enhanced total phenolic compound content within subzones with better water status. More water or iron stressed subzones restricted C6-alcohols contents with respect to less stressed. Without significant effects on vine vigor, yield or berry size, the incidence of iron chlorosis increased the concentrations of some specific terpenes, C13-norisoprenoids, volatile acids and volatile phenols. These results showed that low to moderate iron stress can have positive effects on grape aromatic quality, and demonstrated that Chl can be a useful tool in precision viticulture, to map the aromatic potential within rainfed vineyards affected by iron chlorosis.
... Water scarcities in irrigated agricultural regions globally are putting greater pressure on irrigators to maximize its productive use [1]. Extensive irrigation research on grapevines has shown that soil water deficits resulting in vine water stress can lead to reduced leaf gas exchange, accelerated ripening, losses of yield via lowered berry weight, and negatively impact grape composition and wine quality [2][3][4][5][6][7]. These responses are genotype (cultivar)-dependent within the Vitis vinifera L. species; for example, 'Grenache' vines regulated their hydraulic pathway more strongly than 'Chardonnay' in response to water stress [8]. ...
Article
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The evolving spatial and temporal knowledge about vineyard performance through the use of remote sensing offers new perspectives for vine water status studies. This paper describes the application of aerial thermal imaging to evaluate vine water status to improve irrigation scheduling decisions, water use efficiency, and overall winegrape quality in the Coonawarra viticultural region of South Australia. Airborne infrared images were acquired during the 2016 and 2017 growing seasons in the region of Coonawarra, South Australia. Several thermal indices of crop water status (CWSI, Ig, (Tc-Ta)) were calculated that correlated with conventional soil and vine water status measures (Ψpd, Ψs, gs). CWSI and Ig could discriminate between the two cultivars used in this study, Cabernet Sauvignon (CAS) and Shiraz (SHI), as did the conventional water stress measures. The relationship between conventional vine water status measures appeared stronger with CWSI in the warmer and drier season (2016) compared to the cooler and wetter season (2017), where Ig and (Tc-Ta) showed stronger correlations. The study identified CWSI, Ig and (Tc-Ta) to be reliable indicators of vine water status under a variety of environmental conditions. This is the first study to report on high resolution vine water status at a regional scale in Australia using a combination of remote and direct sensing methods. This methodology is promising for aerial surveillance of vine water status across multiple blocks and cultivars to inform irrigation scheduling.
... Wine grapes are often produced in Mediterranean climates characterized by warm and dry summers. In these regions, deficit irrigation can be applied in vineyards to improve water use efficiency, reduce canopy vigour, and affect grape composition when compared to full irrigation (Castellarin, Matthews, Di Gaspero, & Gambetta, 2007;Herrera et al., 2015) and wine aroma by increasing fruity and decreasing vegetal notes (Chapman, Roby, Ebeler, Guinard, & Matthews, 2005;Song, Shellie, Wang, & Qian, 2012). Despite the majority of the studies were conducted considering red grape varieties; recent studies had indicated that deficit irrigation affected grape and wine composition also in white grape varieties (Balint & Reynolds, 2013;Ortega-Heras et al., 2014;Savoi et al., 2016;Trigo-Córdoba, Bouzas-Cid, Orriols-Fernández, & Mirás-Avalos, 2015;Vilanova et al., 2019). ...
... MPa) produced grapes with more fruit flavour, with intense red and blackberry, jam or cooked berry and dried fruit aromas, combined with less astringency, bell pepper and black pepper aromas and vegetable notes, than those wines from irrigated vines [157] . ...
Thesis
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As it happens with other grape varieties, Baga is prone to high productivity and also to rot, due to the production of compact clusters and thin skin berries. The occurrence of some diseases and excessive productivity are frequently associated, and therefore, yield control is an important issue. Fruit thinning and the application of growth regulators do not produce intended effects, revealing inconsistencies, technical difficulties to implement and high costs. Manual cluster thinning is time-consuming and chemical thinning is difficult to control, yielding random results depending on variety, phenological status and dosage of the used chemicals. A three-year study was carried out, testing the production control techniques "early severe leaf removal" (manual and mechanical, MAD and MED, respectively), "Double Maturation Raisonnée" (DMR) and "manual bunch thinning" (MBT). The objective of this work was to compare the effects of MAD, MED, DMR and MBT as methods of yield control and to demonstrate their individual effects on Baga variety, quality of grapes, musts and resulting wines. Using MAD, the first six basal leaves were removed at flowering, while MED was performed using the leaf removal machine in the fruiting zone on both sides of the vine at the same period. MBT was performed at veraison, limiting one bunch per shoot. DMR was performed 15 days before harvest, leaving shoots and bunches hanging on the wires. A randomized complete block design with four replications was used. The results reflected some influence of the different climatic conditions over the effects of each method studied on three harvests. However, some tendencies could be found: the techniques studied decrease vine yield; MAD, MED, DMR and MBT showed successfully lower yields; MAD, MED and DMR showed lower incidence of rot and cluster compactness, as well as some improvements in the composition of the must (something not presented in MBT); the wines produced with DMR and MED presented good sensorial quality, similar or superior to the used commercial References, while wines produced under MAD and MBT conditions presented superior results compared to Control (CTR) but not to the References; MED proved to be a lower-cost alternative to the other methods.
... Managing irrigation allows preservation of the optimal grape characteristics which ensure wine quality (Romero et al. 2019, Lizama et al. 2021. The effect of vine water status on berry and wine sensory traits and aroma precursors have been previously reported (Chapman et al. 2005, Bindon et al. 2007, Koundouras et al. 2009). More recently, the effect of water deficit was investigated on terpenes, including several key compounds that contribute to floral and fruity notes. ...
Article
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Background and Aims: Water deficit modifies the concentration of the aroma compounds of grape berries, but little information is available on the effect of deficits applied at different phenological stages. We evaluated the effect of deficit irrigation on glycosylated volatile organic compounds (VOCs) responsible for the aroma of berries of Sangiovese and Merlot cultivars grafted on 1103P or SO4 rootstocks. Methods and Results: Vines were subjected to either pre-or post-veraison water stress, and berry composition compared against that of fruit of fully irrigated vines. At harvest, a higher concentration of glycosylated VOCs was measured in berries from vines stressed pre-veraison, but while it increased as water deficit increased in Sangiovese, this occurred only at a low or moderate level of stress in Merlot. Post-veraison water stress had a negative or negligible effect on the concentration of glycosylated VOCs in berries at harvest. The rootstock affected the concentration of glycosylated VOCs, particularly in vines stressed pre-veraison, with higher glycosylated VOCs observed for SO4 grafted vines than for 1103P grafted vines. Conclusions: Pre-veraison water deficit enhanced the concentration of berry glycosylated VOCs, while post-veraison deficit did not. The rootstock-scion interaction might amplify the irrigation effect on berry glycosylated VOCs. Significance of the Study: Modifying the timing and volume of irrigation might allow management of berry flavour for improved fruit and wine composition. Irrigation protocols should be tailored for specific cultivar-rootstock combinations.
... Since California, like many other wine-producing regions, is characterized by limited rainfall and high evaporative demand during the growing season, irrigation is critical to ensure vineyard productivity. However, the timing and amount of water available can significantly impact the vine vigor, crop yield, and fruit quality (Chapman et al. 2005;Chaves et al. 2007;Webb et al. 2007). For example, while adequate moisture is needed early in the growing season from bud burst to fruit set to ensure crop yield, moderate water stress is preferred later in the growing season to enhance fruit quality (Lobell et al. 2007;Zarrouka et al. 2012). ...
Article
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Remote sensing-based models are the most viable means of collecting the high-resolution spatially distributed estimates of evaporative water loss needed to manage irrigation and ensure the effective use of limited water resources. However, due to the unique canopy structure and configuration of vineyards, these models may not be able to adequately describe the physical processes driving evapotranspiration from vineyards. Using data collected from 2014 to 2016 as a part of the Grape Remote sensing Atmospheric Profile and Evapotranspiration Experiment (GRAPEX), the twofold objective of this study was to (1) identify the relationship between the roughness parameters, zero-plane displacement height (do) and roughness length for momentum (zo), and local environmental conditions, specifically wind direction and vegetation density and (2) determine the effect of using these relationships on the ability of the remote sensing-based Two-Source Energy Balance (TSEB) model to estimate the sensible (H) and latent (λE) heat fluxes. Although little variation in do was identified during the growing season, a well-defined sigmoidal relationship was observed between zo and wind direction. When the output from a version of the TSEB model incorporating these relationships (TSEBVIN) was compared to output from the standard model (TSEBSTD), there were large changes to the roughness parameters, particularly zo, but only modest changes in the turbulent fluxes. When the output from TSEBVIN was compared to that of a version using a parameterization scheme representing open canopies (TSEBOPN), the mean absolute difference between the estimates of do and zo were 0.44 m and 0.25 m, respectively. While these values represent differences in excess of 45%, the turbulent fluxes differed by just 13 W m⁻² or 10%, on average. The results suggest that the TSEB model is largely insensitive to changes in the roughness parameters for the range in roughness values evaluated in this study. This also suggests that the requirement for highly accurate roughness values has limited utility in the application of the TSEB model in vineyard systems. Since there is no significant advantage to using the more complex TSEBOPN and TSEBVIN models, it is recommended that the standard model be used.
... Recent studies indicated that water deficit affects grape and wine composition [62,63]. Regulated deficit irrigation has been used to improve berry and wine quality [64], increasing the concentration of terpenes by modulating structural and regulatory genes involved in volatile organic compounds biosynthesis [62]. Water deficit early in the season, before veraison, also stimulated increased anthocyanins and phenolic concentrations [65]. ...
Article
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Viticulture and winemaking are important socioeconomic sectors in many European regions. Climate plays a vital role in the terroir of a given wine region, as it strongly controls canopy microclimate, vine growth, vine physiology, yield, and berry composition, which together determine wine attributes and typicity. New challenges are, however, predicted to arise from climate change, as grapevine cultivation is deeply dependent on weather and climate conditions. Changes in viticultural suitability over the last decades, for viticulture in general or the use of specific varieties, have already been reported for many wine regions. Despite spatially heterogeneous impacts, climate change is anticipated to exacerbate these recent trends on suitability for wine production. These shifts may reshape the geographical distribution of wine regions, while wine typicity may also be threatened in most cases. Changing climates will thereby urge for the implementation of timely, suitable, and cost-effective adaptation strategies, which should also be thoroughly planned and tuned to local conditions for an effective risk reduction. Although the potential of the different adaptation options is not yet fully investigated, deserving further research activities, their adoption will be of utmost relevance to maintain the socioeconomic and environmental sustainability of the highly valued viticulture and winemaking sector in Europe.
... Established is high correlation of flavor characteristics and the possibility the categorization and predict the production technology. The papers [4][5][6], examines developing a list of suitable sensory attributes to perform conventional profiles for food quality assessment. Frequently color and flavor of the product are directly related. ...
Conference Paper
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The present paper discusses instrumental tools for analysis, control and automatic classification of foods . As accents in research is the task of increasing instrumental information in defining the quality of food, data fusion from different sensor systems and fusion classifier based on training samples. We demonstrate of the proposed solutions in the classification of commercial citrus drinks.
... As a consequence, mainly in semi-arid terroirs, supplemental irrigation application modifies the chemical composition of the berry, mainly the concentrations of glucose, fructose, organic acid and mineral elements (estebAn et al. 1999), but also anthocyanins and total polyphenols (sipiorA and GrAnDA 1998). Indeed, some studies pointed out that water deficit improved wine sensory attributes due to an increment of fruity aromas (chApMAn et al. 2005, kounDourAs et al. 2006. ...
Article
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Aroma compounds and skin and seed polyphenols are determinants of wine composition. The aim of this study was to determine the effect of different post-verai-son deficit irrigation strategies on volatile profile and the chemical composition of grape skin and seeds in a 'Cab-ernet Sauvignon' vineyard in Valencia (Spain). Besides a non-irrigated regime (rainfed), irrigation treatments consisted of replacing 25, 50 and 75 % of the estimated crop evapotranspiration (ET C). When compared to rain-fed vines, watering during post-veraison at 75 % of the ET C , decreased concentrations of alcohols but increased those of aldehydes such as hexanal, related to herbaceous (non-desirable) aromas in wines. Irrigating at 25 % or 50 % of ET C resulted in similar concentrations of grape volatile compounds than rainfed vines. There was also a general trend in a reduction in skin to flesh ratio as irrigation regime increased. The concentration of skin anthocyanins and tannins increased with water applications , but seed tannins decreased in the most irrigated regimes. This suggests different effects of water stress on skin and seed polyphenol synthesis and accumulation. For the tannin content, water stress provoked higher tannin mean degree polymerization values, which positively affect must astringency. Under the experimental conditions of the present study, watering at 50 % ET C during post-veraison is the recommended irrigation strategy for optimizing grape composition and improving yield in comparison with rainfed vines. K e y w o r d s : aroma compounds; anthocyanins; tannins; Vitis vinifera; water stress.
... Habran et al. (2016) reported that a mild water deficit and moderate N availability affected berry metabolism towards the synthesis of phenolic and aroma compounds. Chapman et al. (2005) and Habran et al. (2016) found that vegetal aroma contributes, especially bell-pepper, is reduced under water deficit whereas fruity aroma descriptors were higher under these conditions. However, this cannot be proven because there was no water stress for the vines, and there were no significant differences detected in tasting. ...
Article
Agroforestry systems (AF) consisting of grapevines and trees, may lead to resource competition for water and nutrients. This study aimed to evaluate the impact of a combined cultivation on water relations, nitrogen nutrition and the resulting wine quality. ¹⁵N-labeled inorganic nitrogen (N) sources were used to quantify net N uptake capacity. N content and δ¹⁵N natural abundance were analysed as integrating parameters of N nutrition. Leaf water potential (ψleaf) was determined to evaluate the water status of grapevines. Wine quality was evaluated by chemical and sensory analyses. In result, AF system reduced leaf water potential and increased net N uptake capacity in grapevines. However, chemical composition and sensory quality of the wine were not significantly affected in the present system consisting of Riesling, Sauvignon Blanc, oak and poplar. Nitrogen availability of grapevines was favourable and water relations were improved, whereas wine quality was similar when grown with trees or without. Trees were able to reduce water and nitrogen losses without negative effects on wine quality. This work provides information on benefits and limits for intercropping of trees and grapevines in terms of performance of grapevines and wine quality compared to traditional vineyard systems.
... Giovanelli and Brenna (2007) stated that climatic conditions, temperatures during ripening and cluster sun exposure are all significant factors that affect levels of varietal aroma compounds in grape berries. Many researchers have demonstrated that various viticulture practices can affect the composition of volatile compounds in grape and wine, such as irrigation treatment (Chapman et al., 2005); cover crops (Xi et al., (Reynolds et al., 1994). Early defoliation is a very innovative viticulture technique used for yield management. ...
Article
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The aim of this two year study was to evaluate effects of basal leaf removal before blooming on volatile composition of Cabernet Sauvignon wines in the Ilok vineyards (eastern Croatia). During two consecutive vintages (2013, 2014), two different treatments of basal leaf removal were applied: removal of 3 and 6 leaves, and control without leaf removal. Volatile compounds of resulting wines were identified and quantified by gas chromatography coupled with mass spectrometry. Organic acids and higher alcohols remained unaffected by treatments of early defoliation wine, except acetic acid and 2-methyl-6-hepten-1-ol. Early leaf removal was affected on six esters concentration only in the 2014 with different outcome. For compounds unaffected by defoliation, vintage was statistically significant source of variability, as the results of multivariate analysis have confirmed. Defoliation treatments in Cabernet Sauvignon wines from eastern continental part of Croatia should be adjusted to the weather condition in growing season.
... The many abiotic stresses that significantly limit the distribution of grapes around the world and reduce crop yield, as is the case of water deficit, can also be used in a positive way to enhance berry flavor and quality characteristics (Chapman et al., 2005). Deficit irrigation with moderate water stress is in fact associated with increased fruit quality, especially for varieties used in wine production (Williams et al., 2009). ...
Article
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Extensive agricultural losses are attributed to heat, often combined with drought. These abiotic stresses occur in the field simultaneously, namely in areas with Mediterranean climate, where grapevine traditionally grows. The available scenarios for climate change suggest anincrease in the frequency of heat waves and severe drought events in summer, also affecting the South of Portugal. In this work we monitored several productionrelated parameters and evaluated the state ofthe oxidative stress response apparatus of two grapevine varieties, Touriga Nacional (TN) and Trincadeira (TR), with and without irrigation, during three field seasons (2010 to 2012). Overall, results point to a high correlation of most yield and stress-associated parameters with the specific characteristics of each variety and to each season rather than the irrigation treatments. In the season with the driest winter, 2012, the lack of irrigation significantly affected yield in TR, while in the two other seasons the impact of the irrigation regime was much lower. In 2012, the yield of TN was affected by environmental conditions of the previous season. Theirrigation treatments significantly affected berry size rather than quality. © 2018, Instituto Nacional de Investigacao Agraria e das Pescas.
... Grape sensory properties such as fruity or herbaceous characters, as well as juiciness, are negatively influenced by elevated temperatures during the growing season, even when all grapes are harvested at similar soluble solids. 28 Besides, Chapman et al. 29 reported that water deficits in grapevines may have led to a greater flux of carbon via alternative biosynthetic pathways, leading to an increase in amino acids (precursors of esters in wines) and in carotenoids (precursors of C 13 -norisoprenoids). Thus, grapevine maturity involves many physiological processes, including translocation, accumulation and metabolism of principal components within the grape berry. ...
Article
Background: Carignan noir is one of the minor and ancient varieties from the Chilean wine scenario, which has had a resurgence due to its rediscovered oenological potential when cultivated under the conditions of the interior dryland area. Under these growing conditions Carignan noir wines stand out as fruit driven and fresh when compared to those coming from other growing areas. On the other hand, it is well known that wine aroma composition depends mainly on variety, viticultural management, and winemaking. Thus, the aim of this work was to study volatile composition of wines from Carignan noir grapes coming from ungrafted and grafted onto País grapevines, in ten sites of the Maule Valley (Chile) during two consecutive vintages. Results: Higher alcohols were the most abundant volatile compounds whereas, ethyl esters and ß-damascenone were the most odoriferous compounds according to their OAV. The dominant factor in Carignan noir wine volatile composition was season, whereas rootstock did not have a significant effect in differentiating the wines. In terms of climate, cold nights during the month prior to harvest correlated with higher linalool, α-terpineol and trans-3-hexen-1-ol content. Biologically effective degree-days index was inversely correlated with isoamyl acetate and 2-phenylethyl acetate content. Huglin's Heliothermal and the Average Mean Temperature of the Warmest Month indexes were inversely correlated with ethyl vanillate, ethyl hexanoate and ethyl octanoate content. Conclusion: Site climate conditions were related to the accumulation of certain wine volatile compounds. This information may be useful for devising new Carignan noir vineyard management strategies in order to improve wine quality or to adjust site selection approaches in order to maximize grape/wine volatile composition according to wine style.
... Water availability is a critical limiting factor in the agricultural industry; therefore, a wide range of new technologies and strategies have been adopted to optimize the agricultural water consumption [1][2][3][4]. Granier et al. [5] argued that the measurements of physiological parameters can provide better information about the whole-plant-level water use with changing atmospheric water demands. For example, the water potential has been used to characterize the plant water stress and to schedule irrigation in vineyards [6][7][8], as well as for nuts trees [9,10], and olive trees [11,12]. ...
Article
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Water stress caused by water scarcity has a negative impact on the wine industry. Several strategies have been implemented for optimizing water application in vineyards. In this regard, midday stem water potential (SWP) and thermal infrared (TIR) imaging for crop water stress index (CWSI) have been used to assess plant water stress on a vine-by-vine basis without considering the spatial variability. Unmanned Aerial Vehicle (UAV)-borne TIR images are used to assess the canopy temperature variability within vineyards that can be related to the vine water status. Nevertheless, when aerial TIR images are captured over canopy, internal shadow canopy pixels cannot be detected, leading to mixed information that negatively impacts the relationship between CWSI and SWP. This study proposes a methodology for automatic coregistration of thermal and multispectral images (ranging between 490 and 900 nm) obtained from a UAV to remove shadow canopy pixels using a modified scale invariant feature transformation (SIFT) computer vision algorithm and Kmeans++ clustering. Our results indicate that our proposed methodology improves the relationship between CWSI and SWP when shadow canopy pixels are removed from a drip-irrigated Cabernet Sauvignon vineyard. In particular, the coefficient of determination (R2) increased from 0.64 to 0.77. In addition, values of the root mean square error (RMSE) and standard error (SE) decreased from 0.2 to 0.1 MPa and 0.24 to 0.16 MPa, respectively. Finally, this study shows that the negative effect of shadow canopy pixels was higher in those vines with water stress compared with well-watered vines.
... Habran et al. (2016) CHAPTER 5: Interaction between grapevines and trees: effects on water relations, nitrogen nutrition, and wine 100 reported that a mild water deficit and moderate N availability affected berry metabolism towards the synthesis of phenolic and aroma compounds. Chapman et al. (2005) and Habran et al. (2016) found that vegetal aroma contributes, especially bellpepper, is reduced under water deficit whereas fruity aroma descriptors were higher under these conditions. However, this can not be proven because there was no water stress for the vines, and there were no significant differences detected in tasting. ...
Thesis
Viticulture and the vinification of vines (Vitis vinifera L.) to wine is an important branch in agriculture world-wide. Berry quality and the associated wine quality are the driving factors here. Nitrogen (N) is the most important plant nutrient for the grapevine. In addition to its influence on vegetative and generative growth, it determines significantly the metabolite composition and the oenological parameters of the grape berry. Nitrogen is present in various forms, such as nitrate, ammonium or amino acid, in the individual plant organs and is used differently by the grapevine. Grapevines are believed to have the ability to assimilate N in various forms, which in turn may affect the quality of berries and the resulting wine. For a better understanding of the effects of N on berry and wine quality, knowledge of which N-form can be assimilated by the vine and the way that this affects oenological parameters and quality-giving metabolites is essential. To this end, several investigations were carried out at various test levels, starting with hydroponic experiments, a pot experiment and a further field experiment, and on the matured wine. The various N-forms of nitrate, ammonium, urea and the amino acids arginine and glutamine were applied, following which the plant-physiological reactions of the grapevine and quality-determining parameters in berry and wine were measured. Furthermore, a metabolite profile with a focus on phenolic components was prepared and a sensory analysis of the wine was performed. The grapevines in the hydroponics and pot experiments were treated with 4 mM total N. The grapevines in the field experiment were fertilized with 60 kg N ha-1, calculated in relation to the block size. The rootstocks SO4 and RU140 showed similar patterns of N assimilation with respect to the N-form but differed significantly with regard to the level of growth and N content among all N-forms. The N-sensitive rootstock SO4 reacted more strongly than the rootstock RU140 and, therefore, SO4 was used for further experiments. This suggests that grapevines are able to assimilate the amino acids glutamine and arginine, as also shown by the enzymatic nitrate reductase activity and the increased abundance of the transcripts of nitrate reductase and nitrite reductase. Nevertheless, the N-forms NO3- and NH4+ were preferentially assimilated. The assimilation under urea treatment was significantly reduced. In addition to the N-form, the amount of N applied had an influence on N assimilation in the grapevine. With increasing amounts, the vegetative and generative growth increased up to a threshold. However, if this threshold was exceeded, both were significantly reduced. If the grapevine is overfertilized, the sink : source ratio changes, which will lead to a change in the biomass production and furthermore to a saturation and storage of N. In addition, competition for assimilates occurs, this alters the N distribution and N availability within the plant and the berries. The N-form has no influence on berry yield. The oenological and chemical parameters of the must and the wine are of enormous importance for product quality. The key components include pH and acidity, which contribute significantly to the organoleptic properties of wine. Both factors are influenced by the N-form and the amount of N offered. As the amount of N increases, the pH increases and the acidity decreases. The N-forms NO3- and urea and, the zero application (without additional N) show the highest influences. The must weight is a defining factor reflecting the berrys maturity and thus the time of harvest. As the amount of N increases, the must weight decreases. On the one hand, an increased N amount leads to lower acidity in the berry, indicating that more sugar is being stored and that the berry is in an advanced stage of maturity. On the other hand, an increased N amount leads to a decreasing must weight, which leads further to a maturation delay. The total phenolic content increases with increasing N amount, but is highest following zero N application. Tentative phenols measured in the metabolite profile are markedly down-regulated after urea treatment and are upregulated with NO3- following NH4+ treatment. This result might arise from reduced N assimilation in the root and thus reduced N availability for the berries. The influence of N on the aroma and sensory aspects of wine is controversial. The individual aroma attributes show both an increase and a decrease in their intensity attributable to N, mainly urea and NO3-. A marked influence between N-treated vines and the zero application is also apparent. However, these contrasting results clearly show that aroma and thus the sensory characteristics of wine can be influenced both positively and negatively. The results of the aroma and sensory evaluation in the agroforestry system underline once again the controversial influence of N on the sensory features of wine; no significant influence was measured. In summary, N has a significant influence on the vegetative and generative growth of the grapevine. The influence of N can be both positive and negative and is in part directly or indirectly linked to wine quality and should therefore not be ignored.
... Water stress is also an important factor that affects volatile organic compounds in grapes and wine. Cabernet Sauvignon produced under low irrigation is more likely to have a stronger red/blackberry aroma, dried fruit/raisin aroma, jam/cooked berry aroma, and mouthfeel than wines that are normally irrigated (Chapman et al. 2005). Ownrooted Merlot vines in which 35% of the estimated crop evapotranspiration requirement has been reached contain more vitispiranes, b-damascenone, guaiacol, 4-methylguaiacol, 4-ethylguaiacol, and 4-vinylguaiacol than well-watered vines (Qian, Fang, and Shellie 2009). ...
Article
Terpenes significantly affect the flavor and quality of grapes and wine. This review summarizes recent research on terpenoids with regard to grape wine. Although, the grapevine terpene synthase gene family is the largest identified, genetic modifications involving terpenes to improve wine flavor have received little attention. Key enzyme modulation alters metabolite production. Over the last decade, the heterologous manipulation of grape glycosidase has been used to alter terpenoids, and cytochrome P450s may affect terpene synthesis. Metabolic and genetic engineering can further modify terpenoid metabolism, while using transgenic grapevines (trait transfer to the plant) could yield more flavorful wine. We also discuss traits involved in wine aroma quality, and the strategies that can be used to improve grapevine breeding technology.
... L'analisi sensoriale di vini prodotti da viti di Cabernet Sauvignon sottoposte a deficit idrico e irrigate ha evidenziato che il deficit idrico influenzava significativamente l'aroma dei vini favorendo lo sviluppo di note aromatiche legate al frutto maturo, come il fruttato, la mora, il lampone, la marmellata, la frutta passita, mentre diminuivano le note legate al frutto non maturo come quelle di vegetale, di erbaceo, di peperone verde, di pepe nero che invece rimanevano percepibili nei vini prodotti da viti irrigate (Chapman et al., 2005). ...
Article
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Grapevine is the most cultivated fruit crop in the world. Its cultivation is devoted to obtain table grapes consumed as fruit, berries to be dried to obtain raisins, and grapes to be transformed in wine. To produce grapes for wine transformation, a recent approach is to manage cultivation to get the best quality. Among environmental factors, water deficit (WD) has been studied by several authors in its capacity to modify quantity and quality of production. In general a moderate WD improves grape quality, while if too severe the deficit impairs maturation and quality. To achieve this improvement, three irrigation strategies have been proposed recently: deficit irrigation (DI), regulated deficit irrigation (RDI), partial root-zone drying (PRD), and all of these have proved to be beneficial in improving grape quality and achieving a better water use efficiency. WD impacts grapevine physiology through several mechanisms: reduction of shoot growth, stomatal closure, photosynthesis reduction , abscisic acid (ABA) synthesis induction in roots and shoots. Photosynthesis is reduced, but initially this is associated with an increase in water use efficiency. Metabolomic and proteomic studies have shown a modification of gene expression and protein abundance/composition under WD: e.g. proline accumulation in leaves underwent a 2-or 3-fold increase, with an activation of both synthesis and degradation genes. In roots, a more intense suberification under WD has been observed, but also a differentiated modification of hydraulic conductivity of roots: some root-stocks increased their conductivity in early WD, while others decreased it, probably as aspects of different adaptive strategies. The reproductive cycle is modified by WD (fig. 1): berry size is reduced, skin : pulp ratio is often increased, primary and secondary metabolisms are modified. Amino acids are increased, sugars are in some cases increased or remains unaffected, titratable acidity is reduced or remain unaffected. Anthocyanin, proanthocyanidin, C13-norisoprenoid, and thiol concentrations are increased, while terpenes and esters are increased or remain unaltered probably depending on other environmental conditions. Secondary metabolites are crucial for grape and wine quality: under WD conditions some of them may improve their quality, thus benefiting the final product. In red cultivars, anthocyanins are generally increased with a moderate-severe WD; this is resulting from a more intense synthesis supported by an increased expression of genes related with anthocyanin synthesis. Proanthocyanidins (tan-nins) synthesis are rarely modified by WD, while stil-benes, nutraceutical components of wine, were observed to be more synthesised under water shortage. Genes codifying for wine aromatic compound precursors are induced in WD berries, and this results in wines with more fruity and less vegetal aroma. Therefore a moderate WD may be a very important and powerful tool to get a better grape and wine quality , together with a more rational water use in viticulture. Introduzione L'Italia è il primo produttore mondiale di uva sia per valore della produzione (3.615.312 US$) che per quantità (8,15 MT) su una superficie adibita a vigneto di 818.000 ha (OIV, statistiche ufficiali aggiornate al 2009, http://www.oiv.org). Di questa produzione, il 16,2 % riguarda uva da tavola, l'83,8% riguarda l'uva da trasformare in vino (Castellucci 2010). Il livello qualitativo delle uve è un fattore centrale nel determinare il valore commerciale delle stesse; per questo negli anni vi è stata un'attenzione sempre crescente nello studiare i fattori determinanti la qua-lità in vigneto. Nelle uve da vino, che sono l'oggetto di questo lavoro, vi sono diversi aspetti che determi-nano la qualità, tra questi quelli che definiscono la così detta qualità tecnologica, legata al grado zucche-rino, al pH, all'acidità titolabile, e quelli che determi-nano la qualità organolettica e salutistica dei vini, che sono legati alla composizione delle uve in metaboliti
... In the vineyard, [41,42] report that this load regulation does not affect vine water status, nor does it favor increases in leaf area, which is why cluster thinning is understood as a tool used to improve grape quality at the expense of a decrease in yield. However, studies conducted by [43,44] have shown that a reduction in yield is not necessarily associated with significant changes in grape quality and that the final effects on wine quality depend on the timing and intensity of harvest crop load regulation [45]. In this regard, although some studies have reported that cluster thinning increases the concentration of sugars and anthocyanins [46,47], others concluded that this effect is slight or non-existent [41,44,48]. ...
Article
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The efficient use of water in the vineyard requires knowledge of the crop's response to irrigation in terms of production and quality and the interaction of the same with the environmental conditions. In this work, the behavior of a trellis system vineyard in cv. Tempranillo, located in the south-west of Spain, was analyzed for three years in relation to different irrigation strategies based on crop evapotranspiration (ETc), and with two levels of crop load established by early cluster thinning. The response of the vineyard to the same irrigation strategy varied depending on the characteristics of the year. The vineyard’s biomass production increased in a linear trend as annual water status improved. However, during pre-veraison, the water status had a more significant impact on the harvest by affecting bud fertility. The increase in individual cluster weight only partially compensated the loss of yield caused by cluster thinning. The year’s characteristics highly conditioned the response to the irrigation treatment and, together with cluster thinning, modified the characteristics of the musts, although the response was varied.
... The volatile aroma compounds in grapes are derived from the oxidation of fatty acids through the lipoxygenase pathway. Although the levels of volatile compounds in ripe grapes depends on variety, they are greatly affected by seasonally specific climate conditions, sunlight, fungal infections, and vineyard practices that include water management, crop thinning, and defoliation [4][5][6][7]. ...
Article
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The aim of this study was to determine the effects of defoliation performed in the Babica red grape variety on the volatile compounds in produced wine. Three treatments were performed during 2017 and 2018: the removal of six leaves before flowering (FL) and at the end of veraison (VER), as well as control (C). Volatile compounds were analyzed using a gas chromatograph coupled to a mass spectrophotometric detector. Results were statistically evaluated by analysis of variance (ANOVA at the p = 0.05 level) and principal component analysis (PCA). Defoliation treatments were affected by the concentration of several compounds, but only in one year. The VER2017 treatment significantly increased the concentration of three aliphatic esters up to 8 C atoms and octanoic acid ethyl ester. The FL2017 treatment increased the concentration of three aliphatic alcohols. The FL2018 treatment has significantly enhanced the concentration ethyl cinnamate but decreased the concentrations of eugenol and dihydro-2-methyl-3(2H)-thiophenone. Both defoliation treatments reduced the concentration of γ-decanolactone in 2017. Aldehydes, monoterpenoles, and monoterpenes remained unaffected by the defoliation treatments. Vintage was found to be the largest source of variability for most volatile compounds under investigation, which was confirmed by PCA. The effect of defoliation in the mild-Mediterranean climate was found to mostly depend on seasonal weather conditions.
... Deficit irrigation has been shown to be associated with increases in the fruity characteristics in Vitis Vinifera L. cv. "Cabernet Sauvignon" wines, as determined sensorially (Chapman et al., 2005). Also, C 13 -norisoprenoids concentration increased in Cabernet Sauvignon grapes by the degradation of carotenoids, in response to water stress and the influence of sunlight in the fruit zone (Bindon et al., 2007). ...
Article
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Irrigation effects in relation to the environmental conditions on grape aromas are still unknown. This study aims to clarify the effects of water regime on the aromatic composition of “Muscat of Alexandria” grapes under the semiarid climate conditions of eastern Spain and over three seasons. The relationships between total volatile composition in free and glycosidically-bound fractions, vine performance, and grape composition were also assessed. The watering treatments studied were: sustained deficit irrigation (SDI) at 50% of the estimated crop evapotranspiration (ETc); early deficit (EDI), where pre-veraison water deficit was imposed; late deficit (LDI), in which a water shortage was applied during post-veraison; and control (C), irrigated at 100% of ETc during the entire season. The effects of water regimes on volatile and glycosidically-bound composition were different between seasons due to the predominant effect of the environmental conditions on aromatic composition. The seasons with the greater yield were associated to a lower grape aromatic composition, however, this effect at the crop level was less pronounced in the most irrigated treatment. In drier seasons, irrigation delayed ripening and increased the terpene concentration of “Muscat of Alexandria” grapes, showing a high treatment and season interaction. Specific water regimes have the potential to buffer the effects of environmental conditions on the aromatic composition of “Muscat of Alexandria” grapes in a semi-arid climate, as the result of the complex relationships between climatic factors, vine performance and grape maturity.
... These findings are in agreement with Kyraleou et al. (2016) who found that seed and skin extracts from grapes of deficit irrigated at 50% ETc were perceived more astringent than those from non-irrigated grapes. Meanwhile, in Cabernet Sauvignon wines, a standard irrigation treatment was rated significantly higher in astringency than the corresponding minimal irrigated wines (Castellarin et al., 2007;Chapman et al., 2005;Kennedy et al., 2002). Nevertheless, it is difficult to determine how the levels of water supply can influence the polymerization of PAs and, consequently, astringency, mainly because the mechanisms by which PAs are polymerized and astringency is produced are still not clear (Dixon et al., 2005;Zhao et al., 2010). ...
Article
Regulated deficit irrigation (RDI) is an agricultural practice that can enhance grapevine berry and wine quality. However, the effects of water deficit on concentration and composition of proanthocyanidins (PAs) and wine astringency are often limited and contrasting. Therefore, the profiles of PAs were investigated in Cabernet Sauvignon grown at 60% (RDI-1), 70% (RDI-2), 80% (RDI-3), and 100% (conventional irrigation, CI) of estimated evapotranspiration in 2016 and 2017. The treatments, replicated three times, were laid out in a randomized block design where any border effects were avoided. Our results showed that compared with CI, grapes grown under RDI had greater total concentrations of phenolic compounds. Skin PAs content increased in response to the RDI, especially in RDI-1 and RDI-2, while the seed PAs content was relatively insensitive to RDI. Hierarchical cluster analysis indicated that higher percentage of galloylation, molecular mass, mean degree of polymerization and the special extension subunits, such as percentage of (–)-epicatechin-3-O-gallate (%ECG) and percentage of (–)-epicatechin (%EC), led to greater astringency intensity in the wine. However, RDI-1 decreased perceived astringency due to the decreased %ECG and %EC of PAs extension subunits, and increased %ECG of PAs terminal subunits. Our study suggests that the irrigation levels at RDI-2 and RDI-3 can significantly influence the PAs compositions and improve wine astringency perception.
... A decrease of titratable acidity in irrigated vines has been previously found [66] as in this study, and this is most likely due to a higher availability and uptake of potassium from the soil. A higher presence of potassium in the berries of irrigated vines may induce a higher salification of must acids [67][68][69][70]. ...
Article
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The present work studied the effect of two consecutive years of regulated deficit irrigation (RDI) compared to rain fed management on the vegetative growth, yield, and quality of ‘Nero d’Avola’ grapes. The trial was conducted separately in two soils (vertisol and entisol) located at the top and bottom hillside of the same vineyard. Vertisol was characterized by greater depth, organic matter, exchangeable K2O, and total N than entisol. RDI was based on an irrigation volume at 25% of estimated crop evapotranspiration (ETc) up to end of veraison and 10% of estimated ETc up to 15 days before harvest. Predawn water potential (PDWP) was used as indicator of plant water status and irrigation timing. No difference in irrigation management was evident between vertisol and entisol. Under Mediterranean climate conditions, RDI was able to enhance grape yield and vegetative growth, especially in vertisol, but it reduced berry titratable acidity and total anthocyanins. ‘Nero d’Avola’ showed to adapt to drought conditions in the open field. Both soil type and irrigation regimes may provide opportunities to obtain different ‘Nero d’Avola’ wine quality and boost typicality.
... Vitis vinifera is a drought-resistant cultivated species, although this is still controversial (Lovisolo et al. 2002, 2010, Padgett-Johnson et al. 2003, Cramer 2010, Zufferey et al. 2011, and has shown high variability in the stomatal responses to drought among cultivars in the so-called iso/anisohydric continuum (Hochberg et al. 2018), among many others. Grapevines used for oenological purposes are frequently produced under controlled deficit irrigation because of its positive effect on berry composition (Roby and Matthews 2004, Chapman et al. 2005, Castellarin et al. 2007, Deluc et al. 2009, Scholasch and Rienth 2019. Contrasting reports have been published concerning the priming effect of drought on subsequent drought events in grapevines. ...
Article
Background and Aims There is evidence that some species can withstand a stress event better when experienced previously. This capacity could help to increase stress tolerance and resilience under recurrent stresses. To test the effect of a previous season drought imprint on the tolerance to a subsequent drought event, we compared the growth and physiological performance of young cv. Cabernet Sauvignon grapevines growing in a semi‐arid zone in Chile. Methods and Results Treatments were single drought (SD; stressed during the second season) and double drought (DD; stressed during the first and second season). During the second season, DD vines budburst earlier, and leaves were smaller. During the drought period, DD showed a higher rate of photosynthesis despite a similar reduction in the stem water potential and stomatal conductance compared to that of SD. Such difference was associated to a higher maximum Rubisco carboxylation rate observed in DD. Conclusions Our results suggest that grapevines exposed to drought are primed for an upcoming second drought event, the priming lasting from one season to the next, involving contrasting growth and physiological performance. Significance of the Study Our study results contribute information to the emerging debate regarding drought‐priming effects on the tolerance of grapevines to recurrent drought events.
... Moreover, wine type i was the most intense in woody and coffee/chocolate characters. This strong discrimination between herbaceous and fruity attributes within wines produced from the same grape variety has been previously reported [34][35][36][37]. In these studies, the authors also indicated that the descriptive profile of Cabernet Sauvignon wines displayed a dichotomy between herbaceous and fruity characteristics. ...
Article
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Grapes, one of the oldest agricultural crops, are cultivated to produce table fruits, dried fruits, juice, and wine. Grapevine variety is composed of clones that share common morphological traits. However, they can differ in minor genetic mutations which often result in not only notorious morphological changes but also in other non-visible sensorial distinctive attributes. In the present work, we identified three Vitis vinifera cv. Pinot noir clones grown under identical field conditions that showed different grape cluster types. Here, sensorial analysis together with non-targeted metabolite profiles by Ultra High performance Liquid Chromatography (UPLC) couples to Ultra High Resolution Mass Spectrometry (FT-ICR-MS) of wines elaborated from the three different grape cluster types was studied with the aim of (i) finding sensorial differences among these three types of wines, and, if there were, (ii) determining the molecular features (metabolites) associated with these sensorial attributes by a multivariate statistical approach.
... C 6 -Alcohols are responsible, to some extent, for the green herbaceous and vegetable aromas in wines, which is a negative quality attribute (González-Barreiro et al., 2015). The correlations between LWP and C 6 -alcohols are in agreement with sensory evaluation of Baconoir (Balint and Reynolds, 2017), Pinot noir (Ledderhof et al., 2014) and Cabernet sauvignon (Chapman et al., 2005) wines, suggesting that vines with higher water status were associated to more herbaceous and vegetal wines. Several studies have documented that irrigation regimes based on different reference evapotranspiration (ET o ) levels modified the vegetal and herbaceous character of wines. ...
Article
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Water deficit and iron nutritional deficiency (iron chlorosis) are frequent environmental stresses affecting grapevine production in the Mediterranean region. The objectives of this work were (i) to study the combined effects of both stresses on aromatic profile of Tempranillo grapes, occurring simultaneously in the vineyard, and (ii) to evaluate the viability of foliar chlorophyll content at veraison (Chl) to early assess aromatic quality potential of grapes in those conditions. Twenty non-irrigated vineyard subzones (10 m × 10 m each), affected and non-affected by iron chlorosis, were monitored in Ribera del Duero Appellation of Origin (North-Central Spain) during two consecutive seasons. Factorial ANOVA was performed to study the effects of predawn leaf water potential and Chl measured at veraison on the must composition parameters and, specifically, on the concentrations of free and bound aromatic compounds. Water deficit tended to increase color intensity and extractable anthocyanin content of the grapes, whereas the incidence of iron deficiency enhanced total phenolic compound content within subzones with better water status. More water or iron stressed subzones restricted C6-alcohols contents than less stressed subzones. Without significant effects on vine vigor, yield or berry size, the incidence of iron chlorosis increased the concentrations of some specific terpenes, C13-norisoprenoids, volatile acids and volatile phenols. These results showed that low to moderate iron stress can have positive effects on grape aromatic quality, and demonstrated that Chl can be a useful tool in precision viticulture to map the aromatic potential within rainfed vineyards affected by iron chlorosis.
... Estos compuestos estan ligados a aromas herbáceos y a la falta de maduración de la uva. Chapman et al. (2005) observó que el deficit hidrico da lugar a vinos más afrutados y con menos notas vegetales frente a vinos prodcedentes de cepas regadas. ...
Conference Paper
Palabras clave: hexacóptero, reflectancia espectral, compuestos C6, viñedo En el presente trabajo se pretende establecer una metodología de identificación de la composición aromática en la uva Mencía, en las fechas previas a la vendimia, empleando una cámara multiespectral embarcada en un hexacóptero, con la que determinar reflectancias en diferentes longitudes de onda, en base a la posibilidad de intercambiar filtros. La parcela de ensayo se encuentra en el ayuntamiento de Saviñao (Lugo), propiedad de la bodega Ponte da Boga. Para la ejecución del trabajo se han llevado a cabo cinco vuelos al mediodía solar desde el 25 agosto de 2017 hasta el 22 de septiembre de 2017, acompañados del muestreo de uva, con 4 repeticiones por tratamiento establecidos en el viñedo: riego y secano, en cada fecha. Para cada muestra se ha determinado la composición aromática por familias de compuestos volátiles. Los resultados preliminares han permitido definir zonas homogéneas de manejo, así como la predominancia de los compuestos C6 en las viñas bajo el tratamiento riego, ligados a aromas herbáceos y a la falta de maduración de la uva. Se requiere realizar combinación entre los valores de reflectancia obtenidos y la composición aromática determinada en laboratorio para obtener una relación que permita substitr el muestreo de uva y el análisis químico tradicional. INTRODUCCIÓN Conocer la variabilidad espacial del viñedo permite definir zonas del mismo con características homogéneas (van Leeuwen et al., 2004), lo que facilita el manejo diferenciado de un viñedo y adaptar una selección de la uva en base a la calidad de la misma en cada una de estas zonas, con el objetivo de elaborar vinos diferenciados. Sin embargo, obtener esta información a través de medidas directas, a partir de la toma de muestras y el análisis químico de aromas, resulta laborioso, costoso y no permite la toma de decisiones en tiempo real, antes de la vendimia. Recientemente, las técnicas de agricultura de precisión han adquirido relevancia para determinar diferentes propiedades/características de grandes extensiones de cultivo. El empleo de vehículos aéreos no tripulados, equipados con cámaras multiespectrales permite obtener información de toda una plantación con una resolución muy precisa que permite el cálculo de índices que permiten integrar la información sobre diferentes aspectos del viñedo, como vigor, estrés hídrico, estado nutricional, etc. (Jackson et al., 1981).
... At the same time, irrigation management is critical to wine grape production (Ojeda et al. 2002;Pellegrino et al. 2005;Acevedo-Opazo et al. 2010;Bellvert et al. 2015). The timing of irrigation and the amount of water applied can strongly impact vine vigor, crop yield, and fruit quality (Chapman et al. 2005;Chaves et al. 2007;Webb et al. 2007). Therefore, to ensure the water resources are used effectively, information regarding vine water requirements at a sub-vineyard scale is needed so that both the timing and amount of water applied to the vines is appropriate (Arno et al. 2009; Communicated by N. Agam. ...
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California is among the largest wine-producing regions in the world. It is also a region with limited water resources. To ensure that scarce water resources are used effectively, the ongoing Grape Remote sensing Atmospheric Profile and Evapotranspiration eXperiment (GRAPEX) project seeks to improve irrigation management within vineyards by providing remote sensing-based tools that can monitor ET across the continuum from sub-vineyard to regional scales. This study, which was conducted as a part of the GRAPEX project, compares the surface fluxes collected over a pair of vineyards separated by approximately 1 km from 2013 to 2017 to better understand the role of environmental conditions in controlling evapotranspiration. A comparison of the meteorological conditions, which include wind speed, wind direction, air temperature, water vapor pressure, and atmospheric pressure, showed there was no statistically meaningful difference in the measurements of these quantities either between the two vineyards or year to year. In contrast, the comparison of the surface fluxes, and in particular the sensible heat (H) and latent heat (λE) fluxes, showed that there were large inter-site and inter-annual differences. On average, during the growing seasons, H differed by 28 W m−2, while λE differed by 32 W m−2. With coefficients of determination (r2) in excess of 0.90, the differences in the surface fluxes can be largely explained by differences in leaf area index (LAI) and soil moisture content. Since these quantities are, in turn, dependent on vineyard management practices, this work highlights the importance of management decisions for ensuring that limited water resources are used effectively.
... Previous research has revealed that higher concentrations of several classes of secondary metabolites, such as anthocyanins and terpenes, will accumulate in grapevine experiencing water deficit (Castellarin et al., 2007;Deluc et al., 2009;Zarrouk et al., 2012;Savoi et al., 2016Savoi et al., , 2017Gambetta et al., 2020). Nevertheless, few reports have addressed how such modifications in grape metabolites can impact final wine composition and flavour, as most studies have mainly focussed on the sensorial analysis of wine (Balint and Reynolds, 2014;Chapman et al., 2005;Herrera et al., 2015;Intrigliolo and Castel, 2008;Ou et al., 2010). For example, in our previous work (Savoi et al., 2016) we showed, for the first time, a significant increase in terpene synthases in white grapes experiencing water deficit, and it would be interesting to know if this can be translated into more terpenes being present in wines. ...
Article
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Aim. We aimed to study the impact of water deficit on the concentration of key flavour and phenolic secondary metabolites of wines. Methods and results. A drought-stress field trial was conducted on Vitis vinifera cv. Merlot and Tocai Friulano for two seasons. Fully irrigated (C) and deficit irrigated (D) grapes were microvinified and the resulting wines were analysed to determine the concentrations of anthocyanins, tannins, and free and glycosidically-bound Volatile Organic Compounds (VOCs). A descriptive sensory test was undertaken on the same wines. Water stressed grapes produced wines with higher concentrations of anthocyanins in Merlot and of free and glycosidically-bound monoterpenes in Tocai Friulano. Both cultivars displayed higher amounts of glycosidically-bound C13-norisoprenoids. Conclusions. Previously observed drought-induced compositional changes to the grapes were transfered to the wines, with an increase in polyphenols and VOCs. However, the timing and the duration of the water stress in the field only heavily impacted the final wine composition with major metabolic modification when the severe water deficit started early (at approximately 40 days after anthesis) and lasted over the entire season until harvest. Significance and impact of the study. This study highlights the positive role of a controlled water deficit on the composition of the wines in terms of secondary metabolites.
... There is a great potential both for monitoring water stress and scheduling irrigation in commercial orchards (Fernández and Cuevas, 2010). Vineyard water status affects vegetative growth, yield, grape composition, and wine sensorial attributes (Ojeda et al., 2002;Chapman et al., 2005;Chaves et al., 2007). Assessing water status and optimizing irrigation are very interesting issues in most winegrowing countries. ...
Article
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Assessing water status and optimizing irrigation is of utmost importance in most winegrowing countries, as the grapevine vegetative growth, yield, and grape quality can be impaired under certain water stress situations. Conventional plant-based methods for water status monitoring are either destructive or time and labor demanding, therefore unsuited to detect the spatial variation of moisten content within a vineyard plot. In this context, this work aims at the development and comprehensive validation of a novel, non-destructive methodology to assess the vineyard water status distribution using on-the-go, contactless, near infrared (NIR) spectroscopy. Likewise, plant water status prediction models were built and intensely validated using the stem water potential (ψs) as gold standard. Predictive models were developed making use of a vast number of measurements, acquired on 15 dates with diverse environmental conditions, at two different spatial scales, on both sides of vertical shoot positioned canopies, over two consecutive seasons. Different cross-validation strategies were also tested and compared. Predictive models built from east-acquired spectra yielded the best performance indicators in both seasons, with determination coefficient of prediction (RP2) ranging from 0.68 to 0.85, and sensitivity (expressed as prediction root mean square error) between 0.131 and 0.190 MPa, regardless the spatial scale. These predictive models were implemented to map the spatial variability of the vineyard water status at two different dates, and provided useful, practical information to help delineating specific irrigation schedules. The performance and the large amount of data that this on-the-go spectral solution provides, facilitates the exploitation of this non-destructive technology to monitor and map the vineyard water status variability with high spatial and temporal resolution, in the context of precision and sustainable viticulture.
Article
Wine encapsulates the expression of multiple inputs – from the vineyard location and environment to viticultural and winemaking practices – collectively known as terroir. Each of these inputs influence a wine's chemical composition and sensory traits, which vary depending on cultivar as well as provenance. These aspects underpin the overall concept of wine typicity, an important notion that enables wine from a delimited geographical area to be differentiated and recognisable in national and international wine markets. Indeed, consumers are increasingly more aware of the significance of regionality and may use this to influence their purchasing decisions. Understanding which sensory attributes represent regional typicity and how these are best conveyed to consumers is therefore important for the prosperity and reputation of producers. As reviewed herein, the sensory typicity of wine can be identified using different types of testing methods, with the most effective being a combination of approaches, such as sorting task in combination with descriptive sensory analysis. Consumer perceptions of regionality and wine typicity are then examined to provide insight into their behaviours. This includes consideration of the importance of origin to perceptions of quality and typicity, in terms of meeting expectations and engaging consumers. Based on the literature reviewed, it is proposed that wine typicity can be defined as a juxtaposition of unique traits that define a class of wines having common aspects of terroir involving biophysical and human dimensions that make the wines recognisable, and in theory, unable to be replicated in another territory.
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Wine grape is usually grown under water deficit conditions that could negatively impact plant reserves, including the organic carbon storage in perennial organs such as woody stems. Assessing the carbohydrate status in woody organs is therefore of interest as it can influence vegetative growth in the successive season. In this study, we aimed to apply an on-solid colour reaction (using Lugol's iodine solution) coupled with reflectance spectroscopy detection to assess the grapevine canes' starch accumulation in response to short drought periods. We used two Vitis vinifera cultivars ('Cabernet Sauvignon' and 'Syrah') that were subjected to three different water conditions (well-watered; early water stress; late water stress) during the growing season as case study. We sampled woody stem tissue during winter rest. The results showed that water stress reduced the starch storage in 'Syrah', especially when imposed late and recovery time was not enough for carbon restoration, while 'Cabernet Sauvignon' was not affected. The results showed that the sensitivity of the method used here is adequate to assess starch accumulation differences due to drought treatments in grapevine canes. Moreover, the analytical approach appears fast, low cost, and promising for future physiological and agronomical research applications.
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Despite Vitis vinifera L. is a drought-tolerant species—rainfed traditionally grown in a very diversity of climates—irrigation has more and more become a usual practice aimed to obtain regular yields along seasons and to control must composition. Results on vineyard irrigation are dependent on the timing, length and intensity of the water deficit. From budbreak to flowering, shoot growth is very sensitive to water stress, while reproductive growth is almost unaffected. Severe water deficit during fruit set can reduce yield by affecting ovary cell multiplication and expansion. During maturation water stress induces yield reduction by limiting berry growth; along this phase must composition is also affected. There is a positive, linear relationship between must sugar content and available water; however, no relationship has been found to either total acidity or pH. Biosynthesis of anthocyanins and fruity aromas is enhanced by water deficit. Usually, wines from moderate irrigation treatments scored the highest. There is a general agreement that severe, long water deficits diminish must quality, leaf area, fertility and yield, and it has a negative carryover effect on the next seasons by limiting wood reserves to be used the following seasons.
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The main purpose of this chapter is to summarize recent developments of grape composition and the dynamic of the evolution of the most important compounds during this process, as well as the different factors that could determine how this evolution occurs. In addition, several key aspects of different methodologies used for the evaluation and quantification of the most important parameters for the monitoring of grape maturation will also be considered.
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The carbon stable isotopic composition, as indicated by the δ¹³C value, of wine ethanol is inherited from berry sugars, but little is known about the variation in sugar δ¹³C values of Japanese grapes relative to overseas grapes. This study found a large variation in sugar δ¹³C values of Chardonnay grapes grown in Japan (−27.2 ± 0.9‰, mean ± standard deviation, n = 33), with sugar δ¹³C values depending on the δ¹³C values and content of monosaccharides. After complete fermentation, the carbon isotope discrimination between berry sugars and wine ethanol was 1.5 ± 0.1‰. Ethanol δ¹³C values and carbon isotope discrimination enabled prediction of sugar δ¹³C values in the original must. Imported wines had higher sugar δ¹³C values than those of wines made from Japanese grapes, suggesting drier overseas viticulture conditions. The determination of sugar δ¹³C values in grape berries provides valuable information for viticulture and wine authentication.
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Prosecco wine is one of the most important products of the Italian oenological landscape. Its production is strictly regulated by several disciplinary. Thus, it is important to verify the quality of the final product, to defend the uniqueness of this wine. This work describes a rapid method to discriminate among varieties of Italian Prosecco wine using the volatile-fraction distribution as an untargeted fingerprint. The volatile profile corresponds to gas-chromatograms obtained in head-space mode. Principal components analysis of chromatograms allows discriminating the Prosecco samples depending on geographical origin, cultivation practices, and wine-making technologies. In particular, conventional vs. biological agriculture and manual vs. mechanical harvesting give well-separated clusters when projected on a scores plot. Influence plots allow evaluating which variables are the most effective to describe the differences between oenological classes, which are declared in the label and coded in the disciplinary of origin denomination. The identification of discriminating molecules in the volatile profile is also performed by Kovats indexes. Thus, possible chemical markers for the classification of Italian Prosecco wines are appointed.
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Wine final color, taste and aroma are closely related to the accumulation of secondary metabolites that may be affected by deficit irrigation applied in viticulture. A two-year study was conducted to assess the different fractions of crop evapotranspiration (ETc) irrigation replacement on wine composition, addressing the analysis of flavonoids and volatiles under context of global warming. Irrigating with 100% ETc (full grapevine demand) enhanced wine hue, antioxidant capacity, and some aromas; however, it came with a diminution of flavonoids and a less stable flavonoid profile. Replacing 25 and 50% ETc in wine grape improved wine color intensity, concentration of flavonoids, and shifted the aromatic profiles. These treatments increased some terpenes and esters which may enhance the desirable aromas for Cabernet Sauvignon, and decreased C6 alcohols related to unpleasant ones. Therefore, despite the warming trends in Mediterranean climates, 100% ETc irrigation would be not advisable to improve or maintain wine quality, and 50% ETc was sufficient.
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Plants are exposed to numerous abiotic stresses. Drought is probably the most important of them and determines crop distribution around the world. Grapevine is considered to be a drought-resilient species, traditionally covering semiarid areas. Moreover, in the case of grapevine, moderate water deficit is known to improve the quality traits of grape berries and subsequently wine composition. However, against the backdrop of climate change, vines are expected to experience sustained water deficits which could be detrimental to both grape quality and yield. The influence of water deficit on two Greek Vitis vinifera L. cultivars, 'Agiorgitiko' and 'Assyrtiko', was investigated during the 2019 and 2020 vintages. Vine physiology measurements in irrigated and non-irrigated plants were performed at three time-points throughout berry development (green berry, veraison and harvest). Berry growth and composition were examined during ripening. According to the results, water deficit resulted in reduced berry size and increased levels of soluble sugars, total phenols and anthocyanins. The expression profile of specific genes, known to control grape color, aroma and flavor was altered by water availability during maturation in a cultivar-specific manner. In agreement with the increased concentration of phenolic compounds due to water deficit, genes of the phenylpropanoid pathway in the red-skinned Agiorgitiko exhibited higher expression levels and earlier up-regulation than in the white Assyrtiko. The expression profile of the other genes during maturation or in response to water deficit was depended on the vintage.
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Merlot is one of the most cultivated cultivars in the world since it easily adapts to different climatic conditions. Leaf removal (LR) is commonly used for red berry varieties but in cold wine-growing areas and nothing has been reported on the effects of LR on Merlot cultivated under Mediterranean climate. The aim of the research is to evaluate the influence of this technique on grape and wine quality as well as wine aroma potential of Merlot cultivated in Sicily. Vines were subjected to LR for two consecutive years, and productivity and chemical parameters were monitored in grapes, whereas chemical composition and volatile aroma compounds, analyzed by gas chromatography mass spectrometry, were monitored in wines. LR positively influenced the plant yield, increased the sugar content and decreased the acidity in grapes at harvest. The wines of the defoliated treatment showed a higher content of total polyphenols and anthocyanins, higher color intensity, and lower color hue. Merlot wines obtained under Mediterranean climate were characterized by a high amount of esters and varietal aromas and the content of most of volatiles were even increased by the LR with positive effects on the aroma potential of Merlot wines. The vintage affected almost all the studied parameters with the warmer and dryer vintage enhancing the LR effects on grapes and wines. This is of great interest in the light of the climate changes towards the global warming and the increasing aridity of the Mediterranean area.
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Quantity and characterization of flavonoids were determined in skins isolated from Vitis vinifera L. cv. Cabernet Sauvignon berries during fruit ripening and at different postveraison water deficits. The per berry amount of anthocyanin, flavonol, and pigment incorporation into proanthocyanidins increased with maturity. The amount of proanthocyanidin extension subunits did not vary with maturity, although the extension subunit composition did. The apparent average degree of polymerization of proanthocyanidins increased with maturity. Incorporation of pigmented material into the proanthocyanidins, together with the apparent increase in average degree of polymerization, suggests that additional terminal subunits, which are not flavan-3-ols, accumulate during fruit ripening. Increased vine water deficit caused small increases in anthocyanins and decreases in flavonols. Red wine flavonoid amounts indicate that postveraison water deficits affect red wine flavonoids primarily by altering berry size and perhaps secondarily by modifying flavonoid biosynthesis.
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An analytical method to determine the volatile components of wines is proposed for studying Merlot noir cultivar clones (181, 182, 343, 347) produced in 1993 and 1994. The substances were 3-isobutyl-2-methoxypyrazine, three norisoprenoid-ketones, free terpenols and the alcohols with six carbon atoms. Wines made from the 1993 harvest contained more 3-isobutyl-2-methoxypyrazine and fewer norisoprenoids-ketones because of the cooler climatic conditions in that year. The wine of clone 182 had higher levels of 3-isobutyl-2-methoxypyrazine for the two harvests.
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The effects of moderate irrigation, compared with non-irrigation, on leaf photosynthesis and transpiration, grape yield, and quality parameters, were studied over ten years in two Spanish cultivars (Tempranillo and Manto Negro) of field-grown grapevines ( Vitis vinifera L.). The aim was to increase our knowledge of the relationships between water availability, canopy water losses, photosynthesis, and fruit yield and quality. A second aim was to analyse some of the mechanisms of photosynthetic down-regulation under drought, such as the capacity for RuBP regeneration and Rubisco activity. Moderate irrigation improved plant water status, leaf photosynthesis and transpiration. Considering the results over ten years, soil water availability (estimated as pre-dawn leaf water potential, Ψ<sub>PD</sub>) largely determined leaf photosynthesis and leaf transpiration. Decreased photosynthesis was due to both stomatal and non-stomatal factors. The latter were related to decayed electron transport rate and reduced RuBP regeneration capacity, but not to decreased Rubisco activity. Moderate irrigation also improved grape yield, although this effect was much larger in Tempranillo than in Manto Negro. Moreover, the correlation between photosynthesis and grape yield was significant in Tempranillo, but not in Manto Negro. In contrast, the correlation between Ψ<sub>PD</sub> and several parameters reflecting fruit quality (such as soluble solids and total polyphenol content) was significant only in Manto Negro. These results suggest that there is a close link between water availability and grape yield, mostly through water stress effects on photosynthesis. Drought effects on grape quality are linked to water availability but not to photosynthesis or yield.
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The influence of naturally occurring and added methoxypyrazines on wine aroma was assessed by sensory evaluation. Addition of 2-methoxy-3-(2-methylpropyl)pyrazine or 2-methoxy-3-(1-methylethyl)pyrazine, at 1 ng/L and 2 ng/L, respectively, significantly influenced the aroma of a methoxypyrazine-free white wine. Ranking of samples prepared by addition of 2-methoxy-3-(2-methylpropyl)pyrazine (0-32 ng/L) to the methoxypyrazine-free wine showed that the compound contributed significantly to vegetative aroma at 8 ng/L or above. A range of commercial Sauvignon blanc wines was assessed by scoring for vegetative varietal aroma intensity and methoxypyrazine aroma intensity. Comparison with the naturally occurring methoxypyrazine concentration showed that wines of high (> 26 ng/L) and low (< 12 ng/L) methoxypyrazine concentration were clearly distinguished on the basis of vegetative varietal aroma or methoxypyrazine aroma. It is concluded that methoxypyrazines do contribute to the characteristic vegetative aroma of Sauvignon blanc wines.
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A protein precipitation assay was used to separately monitor tannin concentrations in skins and seeds of three red Vitis vinifera winegrape varieties: Cabernet Sauvignon, Syrah and Pinot noir. In 1998, seeds of Cabernet Sauvignon berries showed highest values before veraison, after which the seed tannin per berry declined and remained fairly constant during the four weeks before harvest. In 1999, the decline in seed tannin was slower but reached nearly the same value by harvest as in 1998. In 1998 and 1999, the skin tannin per berry changed little in Cabernet Sauvignon, and in both years the amount of tannin in skins and in seeds was nearly equal on a per berry basis by harvest. Syrah exhibited a pattern similar to Cabernet Sauvignon except that there was nearly three times as much seed tannin per berry as skin tannin. Results with seeds of Pinot noir in 1998 were problematic because of variation observed among replicate samples. Nevertheless, as with Cabernet Sauvignon, the amounts of tannin in seeds and skins of Pinot noir were practically the same at harvest. In 1999, tannin concentrations were measured in commercial wines made from vineyards that were monitored for tannin concentrations in the fruit. There was no relationship between the total tannin per berry and the amount of tannin in the resulting wine among the three varieties studied. Seed tannin per seed varied only 40% among the three varieties, but seed tannin per berry was different by 235%. Thus, the major factor contributing to the difference in total seed tannin per berry among the three varieties was the number of seeds per berry, rather than the amount of tannin per seed.
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