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BACKGROUND: Genetic breeding is essential to develop grapevine genotypes adapted to warm climates and resistant to pathogens. Traditionally cultivated Vitis vinifera is susceptible to biotic and abiotic stresses. Winemakers and consumers, however, perceive wines from non‐vinifera or hybrid cultivars as inferior. In this study, sensory analyses and comprehensive metabolite profiling by targeted and untargeted approaches were used to investigate the oenological potential of wines from grapes of genotypes developed throughout four breeding cycles to improve climate adaptation, sugar contents and berry color. RESULTS: Novel genotypes had higher yields and the wines exhibited increased contents of polyphenols, including anthocyanins. Volatile monoterpenes in the wines decreased throughout breeding cycles in the absence of selective pressure. Polyphenol contents were higher in intermediate wines, with hydroxytyrosol contents reaching up to three times reported values. Mouthfeel attributes astringency, leafy taste, flavor and body, and persistency showed significant correlation with untargeted features. Supervised model‐based analyses of the metabolome effectively discriminate wines from distinct genetic origins. CONCLUSION: Taken together, the results demonstrate the potential of novel grapevine genotypes to a more sustainable viticulture and quality wine production in warm climates. Comprehensive metabolite profiling of the wines reveals that genotype clustering is dependent on the chemical class and that traits not submitted to selective pressure are also altered by breeding. Supervised multivariate models were effective to predict the genetic origin of the wines based on the metabolic profile, indicating the potential of the technique to identify biomarkers for wines from sustainable genotypes. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

AbstractGrapes are renowned for their health-promoting properties due to polyphenols, particularly anthocyanins in red grapes and flavonols in white grapes. This study evaluated the total antioxidant capacities (TAC) of specific grape varieties (Sultaniye, Chardonnay, Shiraz, Carignan, Alicante Bouschet, and Merlot) using the CUPRAC (CUPric Reducing Antioxidant Capacity) and ABTS/HRP (2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)/horseradish peroxidase) methods. Additionally, total phenolic, flavonoid, and anthocyanin contents were determined via Folin Ciocalteu, AlCl3/NaNO2, and pH differential methods. Primary phenolic compounds were identified with High-Performance Liquid Chromatography-Photodiode Array (HPLC-PDA). TAC values of the grape juices (mmol Trolox L−1) ranked as Alicante > Shiraz > Sultaniye > Carignan > Merlot > Chardonnay by CUPRAC, and Shiraz > Alicante > Merlot > Carignan ≥ Sultaniye >  Chardonnay by ABTS/HRP and for skin extracts (mmol Trolox g−1), Carignan > Alicante > Shiraz > Merlot > Chardonnay > Sultaniye by CUPRAC, and Carignan > Shiraz > Alicante > Merlot > Chardonnay >  Sultaniye by ABTS/HRP. The study demonstrated a strong correlation between phenolic composition and TAC values in grape samples, with anthocyanins as the predominant family contributing significantly to TAC. Varietal and intra-fruit differences in specific phenolic compounds were found to account for variations in observed TAC levels. Specifically, grape skin samples showed a more robust correlation between antioxidant capacity and total phenolic content (r = 0.986) than grape juices (r = 0.777). These findings underscore the considerable variation in antioxidant potential among grape varieties and emphasize the critical role of phenolic composition in the health-related benefits of grape consumption. [ABSTRACT FROM AUTHOR]

Potassium (K) is essential for the development of grapevines (Vitis vinifera), accumulating into berries during maturation. Elevated K has been associated with high sugar and low acidity in juice. Characterising the accumulation patterns of K and other components in pericarps treated with various experimental factors may indicate potential regulators of berry K levels. A soil fertiliser trial using nutrient solutions with two K supply rates was conducted on potted Shiraz vines during berry ripening. Doubled-K supply increased L-malic acid content in the early-ripening phase, and increased K and magnesium concentrations in the late-ripening phase. Doubled-K supply reduced the ratio of K to sodium in later ripening phases, suggesting that the accumulation of K relative to sodium was limited in more mature berries supplied with extra K. Pericarp water percentage, sugar, K and ATP were correlated in both treatments, indicating links between hydration, solute transport and energy in maturing berries. In a separate rootstock trial over the two growing seasons, Shiraz scions grafted onto 420-A rootstock produced berries with lower K concentration and content than those grafted onto Ramsey or Ruggeri-140 rootstocks and own-rooted vines. This study demonstrated that the K supply and berry ripening phase impacted the berry K level. Increased potassium (K) concentration in grape (Vitis vinifera) berries is associated with loss of acidity and high sugar content in juice. This study demonstrated that the K supply to Shiraz and berry ripening phase could impact the berry attributes and chemical composition at harvest, associated with the linkages between water, sugar, K and ATP. From this study, we suggest that grape berry maturation and composition management may be beneficial. [ABSTRACT FROM AUTHOR]

Garnacha variety is one of the most important red Mediterranean grape cultivars grown in the world. However, it may not reach optimum chromatic characteristics in warm climates such as Andalusia (Southern Spain). This study analyses the impact of the application of microwaves over the crushed grapes (MW) at laboratory scale over two vintages on the characteristics of Garnacha wines elaborated from grapes cultivated in a warm climate as an additional procedure to traditional red winemaking (CT) to obtain highly coloured wines. Oenological and colour parameters were measured to determine the effects of this treatment on wines throughout the winemaking process. Overall, wines made by MW had a higher phenolic content and colour intensity. The analysis of the detailed composition of the wine showed that the treatment with microwaves before the alcoholic fermentation leads to important differences in its colour properties. Thus, the treatment with microwaves induced easily perceptible changes in CIELab coordinates (lower L* and higher a* and C*ab values than CT). Additionally, it also showed to be significantly effective to increase the extraction of phenolic compounds from grape solids into grape juice, both globally (total polyphenol index and Folin–Ciocalteu index), and particularly regarding flavanols and flavonols content. Most of the above-mentioned significant differences remained with ageing. The reported results are promising and the treatment with microwaves in the optimized conditions seems a feasible auxiliary alternative in warm climates, where wines produced from some red grape cultivars often show suboptimal colour characteristics. [ABSTRACT FROM AUTHOR]

Comparative measurements of four Vitis vinifera cultivars were undertaken to assess assimilation tolerance to the high growth temperatures currently pervading Australian and other wine growing regions. The cultivars, cvs. Chardonnay, Merlot, Semillon, and Shiraz, were all grown in common growth conditions, and an hypothesis promulgated genotypic variation in assimilation and in the leaf temperature dependency. Assimilation responses to varying light intensity and to varying chloroplast CO2 at a range of leaf temperatures (15–45°C) were measured in leaves of each cultivar in mid‐summer. Light response curves revealed marked genotype differences in maximum assimilation, but temperature effects also varied. Semillon leaves were most sensitive to temperature, with marked and steep differences in assimilation at different temperatures while Chardonnay and Merlot were least sensitive, with relatively flat responses. There were also marked cultivar differences in response to CO2 and significant effects of leaf temperature. CO2‐saturated assimilation varied markedly, with Semillon and Merlot leaves most responsive to temperature, although there were differences in optimum temperatures and maximum rates. Chardonnay leaves remained least tolerant, with lowest rates of assimilation across most temperatures. Assimilation at 45°C also separated the cultivars and two cultivars had higher rates than at 15°C while Chardonnay and Merlot leaves had higher rates at 15°C. There were no cultivar differences in the temperature dependency of Ribulose 1,5‐bisphosphate (RuBP) carboxylation, but Semillon had a much steeper temperature dependency on RuBP regeneration than the other cultivars. All these responses confirmed the hypothesis and concluded the high‐temperature tolerance of Semillon and Shiraz and the poor adaptability of Chardonnay and possibly Merlot to perform in the current high‐temperature growth conditions. [ABSTRACT FROM AUTHOR]

Screening for drought performance among novel fungi-tolerant grapevine genotypes is a key point to consider in semiarid regions where water scarcity is a common problem during fruit ripening period. It is therefore important to evaluate the genotypes' responses at the level of carbon metabolism and water demand, under water deficit conditions. This study aimed to characterize leaf and plant water use efficiency (respectively named WUEi and WUEpl) of novel INRAE fungi-tolerant genotypes (including LowSugarBerry (LSB) genotypes), under mild and high-water deficit (WD) and to decipher the photosynthetic parameters leading to higher WUEi. For this purpose, experiments were conducted on potted plants during one season using a phenotyping platform. Two stabilized soil moisture capacity (SMC) conditions, corresponding to mild (SMC 0.6) and high (SMC 0.3) WD, were imposed from the onset of berry ripening until the physiological ripeness stage, which was defined as the point at which fruits reach their maximum solutes and water content. At the whole plant level, all genotypes increased WUEpl under high WD. The highest WUEpl was reached for 3176N, which displayed both a high rate of non-structural carbon accumulation in fruits due to high fruit-to-leaf ratio and low plant transpiration because of low total leaf area. However, when normalizing the fruit-to-leaf ratio among the genotypes, G14 reached the highest normalized WUEpl_n under high WD. At the leaf level, WUEi also increased under high WD, with the highest value attained for G14 and 3176N and the lowest value for Syrah. The higher WUEi values for all genotypes compared to Syrah were associated to higher levels of photosynthesis and changes in light-harvesting efficiency parameters (FCO2, qP and qN), while no clear trend was apparent when considering the photosynthetic biochemical parameters (Vcmax, Jmax). Finally, a positive correlation between leaf and plant WUE was observed regardless of genotypes. This study allowed us to classify grapevine genotypes based on their grapes primary metabolite accumulation and water consumption during the critical sugar-loading period. Additionally, the study highlighted the potential drought adaptation mechanism of the LSB genotypes. [ABSTRACT FROM AUTHOR]

Grape-associated microbial community is influenced by a combination of viticultural, climatic, pedological and anthropological factors, collectively known as terroir. Therefore, grapes of the same cultivar grown in different areas can be appreciated for their distinctive biogeographic characteristics. In our previous study, we showed that the phenotypic response of Aglianico and Cabernet grapevines from Molise and Sicily regions is significantly influenced by the prevailing pedoclimatic conditions, particularly soil physical properties. However, the scale at which microbial communities differ could be important in clarifying the concept of terroir, including whether it is linked to the grape variety present in a particular vineyard. To explore this further, in the research presented here, a comparative study on the fungal communities inhabiting the berry surfaces of Cabernet and Aglianico cultivars was conducted on different vineyards located in Southern Italy (Molise, Sicily and Campania regions, the first two of which had been involved in our previous study) by using high-throughput sequencing (HTS) and multivariate data analysis. The descriptive approach through relative abundance analysis showed the most abundant phyla (Ascomycota, Basidiomycota, and Chytridiomycota), families (Cladosporiaceae, Saccotheciaceae, Pleosporaceae, Saccharomycodaceae, Sporidiobolaceae, Didymellaceae, Filobasidiaceae, Bulleribasidiaceae, and Saccharomycetaceae) and genera (Cladosporium, Aureobasidium, Alternaria, Stemphylium and Filobasidium) detected on grape berries. The multivariate data analysis performed by using different packages (phyloseq, Vegan, mixOmics, microbiomeMarker and ggplot2) highlighted that the variable "vineyard location" significantly affect the fungal community, while the variable "grape variety" has no significant effect. Thus, some taxa are found to be part of specific vineyard ecosystems rather than specific grape varieties, giving additional information on the microbial contribution to wine quality, thanks to the presence of fermentative yeasts or, conversely, to the involvement in negative or detrimental roles, due to the presence of grape-deriving fungi implied in the spoilage of wine or in grapevine pathogenesis. In this connection, the main functions of core taxa fungi, whose role in the vineyard environment is still poorly understood, are also described. [ABSTRACT FROM AUTHOR]

Varietal volatile compounds are characteristic of each variety of grapes and come from the skins of the grapes. This work focuses on the development of a methodology for the analysis of free compounds in grapes from Trincadeira, Cabernet Sauvignon, Syrah, Castelão and Tinta Barroca from the 2021 and 2022 harvests, using HS-SPME-GC × GC-TOFMS. To achieve this purpose, a previous optimization step of sample preparation was implemented, with the optimized conditions being 4 g of grapes, 2 g of NaCl, and 2 mL of H2O. The extraction conditions were also optimized, and it was observed that performing the extraction for 40 min at 60 °C was the best for identifying more varietal compounds. The fiber used was a triple fiber of carboxen/divinylbenzene/polydimethylsiloxane (CAR/DVB/PDMS). In addition to the sample preparation, the analytical conditions were also optimized, enabling the adequate separation of analytes. Using the optimized methodology, it was possible to identify fifty-two free volatile compounds, including seventeen monoterpenes, twenty-eight sesquiterpenes, and seven C13-norisoprenoids. It was observed that in 2021, more free varietal volatile compounds were identifiable compared to 2022. According to the results obtained through a linear discriminant analysis (LDA), the differences in volatile varietal signature are observed both among different grape varieties and across different years. [ABSTRACT FROM AUTHOR]

Climate change modifies the base climate of the wine regions and, with it, the structure of their traditional types of wine production, imposing measures to adapt, mitigate, or capitalize on the newly emerging conditions. In order to assess the impact of climate change and establish the appropriate adaptation measures for each wine region, regional and local studies are needed, which allow knowledge of their current climate profile. The aim of this research was to identify the changes that appeared as an effect of climate change in the initial climate profile and the initial structure of the traditional types of wine production of Bordeaux (France), Loire Valley (France), Rhine-Main-Nahe (Germany), La Rioja (Spain) and Cotnari (Romania) wine regions, and also in climate suitability for wine production of the Sussex area from the UK. The study uses multi-year averages for the 1951–1990 and 1991–2010 time periods of reference bioclimatic indices for viticulture, namely the Average Temperature of the Growing Season (AvGST), the Huglin Index (HI), and the Oenoclimatic Aptitude Index (IAOe). The results of this research reveal significant changes in climate suitability for wine production of the studied wine regions: in the Bordeaux wine region, climate change led to the appearance of conditions for the cultivation of the Mediterranean climate varieties Grenache, Syrah, and Carignan; in the cool climate wine regions Rhine-Main-Nahe and Cotnari, traditional producers of white wines, the climate has also become suitable for the cultivation of Pinot noir and Cabernet franc varieties, and implicitly for the production of red wines; in all studied wine regions, the classes of climate suitability for viticulture shifted higher in altitude, as is the case of the La Rioja region, where, in the recent period, the grapevine can be grown up to 922.9 m asl, higher by 206.2 m compared to the 1951–1990 time period; in the low area of each wine region, one or even two new climate suitability classes for wine grape growing appeared. The shifts revealed by this research generate solid conclusions regarding the effect of climatic change on the viticultural potential of geographical areas, namely: in the context of climate change, the altitude of the wine region has a major influence on the evolution of the local viticulture potential; a higher topography allows a better adaptation of the wine region to climate change; low-elevation wine regions are more vulnerable to climate changes, especially the further south they are located; as an effect of climate change, conditions appear in the wine regions for the cultivation of new grapevine varieties and the production of new types of wine. [ABSTRACT FROM AUTHOR]

The flavanol composition of red wine, stemming from grape skins and seeds, is a determinant factor of its quality. It has been proposed that the wine flavanol structure depends on the grape cultivar but with skin-derived flavanols prevailing in traditional red winemaking from mature grapes. However, this has not been confirmed for many cultivars. This study analysed the flavanol composition in grapes, wines, and pomace of Syrah, Marselan, and Tannat, Vitis vinifera cultivars known for their potential to yield tannic wines. Across two vintages, 20 wines were produced through traditional winemaking. Flavanols were analysed by HPLC–MS/MS before and after acid-catalysed depolymerisation of proanthocyanidins. Grapes of different ripeness were considered as vineyard with different agronomical characteristics. Nevertheless, each cultivar exhibited a characteristic flavanol composition in both grapes and wines. Notably, all Marselan wines had high proportions of seed-derived flavanols (high proportions of monomers, dimers and low of prodelphinidins), from grapes with high skin flavanol content. In contrast, Tannat and Syrah wines had high proportions of skin-derived flavanols, irrespective of the corresponding seed flavanol levels in grapes. Flavanol extractability from skins mainly regulated wine composition, being unusually low in Marselan, rising with ripeness in Syrah, and consistently high in Tannat, masking the high seed flavanol contents of its grapes. Therefore, wines with high proportions of seed-derived flavanols can be obtained from fermentative macerations of ripe grapes. Pomaces were found to be a rich source of flavanols, primarily from seeds where they largely remain unextractable. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of different fermentation maceration periods on the physicochemical, chromatic, and phenolic composition of wines made from the 'Bordô' vine. This work was carried out at the Fruit Growing Laboratory of the Federal Institute of Santa Catarina - Canoinhas Campus, in 2022. The 'Bordô' grape was harvested from a commercial vineyard, totaling five treatments consisting of different fermentation maceration periods: 02, 04, 06, 08 and 10 days. The wine was bottled in July 2022, after malolactic fermentation had finished, and the wines were evaluated ten days later. The analyses were carried out in triplicate, evaluating relative density, pH, total acidity, color intensity, color tone and total polyphenols. The data was submitted to analysis of variance and the means were compared using the Tukey test. The fermentation maceration period did not influence the color tone, total titratable acidity, relative density, and pH of the wines. In terms of total polyphenol content and color intensity, there was an increase in these variables as a function of the length of fermentation maceration. Therefore, the length of fermentation maceration influences the color and phenolic composition of wines made from the 'Bordô' grape. [ABSTRACT FROM AUTHOR]

Due to global warming and the effects associated with it, the wine industry is facing important challenges during the winemaking process and the production of high-quality wines. In this study, mistelas and naturally sweet wines were produced with the 'Pedro Ximénez' grapevine cultivar, overripened by sun drying and fermented with and without the presence of grape skins. Some oenological parameters related to alcoholic fermentation and low-molecular-weight polyphenols and furans were considered. Naturally sweet wines with skins presence showed a higher value of viable biomass than those with grape skins absence. However, in terms of density and ethanol production, sweet wines with grape skins absence presented lower and higher values, respectively, than the other elaborations. No significant differences in the organic acids and low-molecular-weight polyphenols and furans contents, with respect to the presence or absence of grape skins, were observed. In this sense, this research proves that the production of sweet wines from sun-dried grapes with the presence/absence of grape skins during alcoholic fermentation could be a possible choice in areas where agro-climatic conditions make it possible. [ABSTRACT FROM AUTHOR]

Background and Aims Drought events have devasting impacts on grape berry production. The aim of this study was to investigate berry growth in the context of leaf stomatal closure under progressive drought stress. Methods Potted grapevine plants (varieties 'Syrah' and 'Cabernet Sauvignon') were evaluated at pre-verasion (30–45 d after anthesis, DAA) and post-veraison (90–107 DAA). Berry diameter, berry absolute growth rate (AGR), leaf stomatal conductance (G s) at midday, plant water potential at predawn and midday (ΨPD and ΨMD, respectively), and soil relative water content were measured repeatedly. The ΨPD-threshold of 90 % loss in stomatal conductance (G s10, i.e. complete stomatal closure) was determined. Data were related to plant dehydration phases I, II and III with corresponding boundaries Θ1 and Θ2, using the water potential curve method. Key Results At pre-veraison, berry AGR declined together with leaf G s in response to soil drying in both varieties. Berry AGR transitioned from positive to negative (shrinkage) values when leaf G s approached zero. The G s10-threshold was −0.81 MPa in 'Syrah' and −0.74 MPa in 'Cabernet Sauvignon' and was linked to boundary Θ1. At post-veraison, berry AGR was negligible and negative AGR values were not intensified by increasing drought stress in either variety. Conclusion Leaf complete stomatal closure under progressive drought stress coincides with cessation of berry growth followed by shrinkage at pre-veraison (growth stage 1). [ABSTRACT FROM AUTHOR]

Wine quality depends on grape quality, which is affected by many factors such as edaphic, climatic and genetic, i.e., cultivar and rootstock. Rootstocks have been selected in worldwide viticulture to confer to vines some adaptation to several types of soil conditions in vineyards, but this adaptation may affect vine physiology and consequently may affect the chemical compounds of grapes, especially their phenolic compounds. Thus, this study compares the chemical composition of grapes and wines, and the sensory profile of wines from vines of the cv. Syrah grafted on two rootstocks, 5C and Gravesac, grown under a biodynamical management system. The results showed higher skin total phenols and skin total tannins in grapes from 5C rootstock. In the resulting wines, the same results were observed. The multivariate analysis demonstrated that the 5C wines presented a higher relationship with all the families of the low-molecular-weight phenolic compounds, while the Gravesac wines showed a strong relationship with acetylated and p-coumaroylated anthocyanins. The sensory analysis showed that the 5C wines presented more color intensity, more astringency and more meaty aromas compared with the Gravesac wines. The results proved that it was possible to obtain grapes and wines of different qualities depending on the rootstocks used under the same climatic and agronomical condition. [ABSTRACT FROM AUTHOR]

The use of rootstocks in modern viticulture is a common practice to avoid the impact of phylloxera and nematodes on vineyards. However, the use of rootstocks affects the metabolic processes of the plant, including the assimilation of water and ions from the soil. In Mexico, as in other grapegrowing countries, the use of rootstocks has become widespread to protect vineyards against harmful microorganisms. Nevertheless, little is known about the impact of rootstock use on the physiology of vine varieties. Therefore, this study aimed to evaluate the effect of rootstocks 110-R, 101-14, 1103-P, and 3309-C on the assimilation of nitrogen, phosphorus, sodium, copper, iron, manganese, and zinc in Merlot, Shiraz, and Cabernet Sauvignon vines from Chihuahua, Mexico. The nitrogen concentration did not vary in relation to the rootstock used or the variety grown. In addition, the concentration of N in vine leaves decreased over time. This is the result of the mobilization of ions to storage areas during the period of foliar senescence. On the other hand, the concentration of phosphorus, sodium, copper, iron, and zinc in the leaves of the varieties and rootstocks studied did not present significant differences. Nonetheless, the concentration of Mn in Merlot leaves was 30% higher in vines with rootstock 1103-P compared to vines with rootstock 3309-C. In this study, it was shown that rootstock impacts ion assimilation in wine grape varieties. [ABSTRACT FROM AUTHOR]

Minirhizotron tubes were installed to monitor root growth dynamics of mature Shiraz grapevines in a rootstock trial established in the hot climate Riverina region of New South Wales, Australia. The vertical root distribution and seasonal root growth dynamics of Shiraz on own-roots and Shiraz grafted on the rootstocks Ramsey, 140 Ruggeri and Schwarzmann was studied for five seasons across a seven-year period to a depth of 60 cm. New root production was significantly influenced by genotype, soil depth, season, growth stage and year. Soil moisture and soil temperature were monitored at 10, 30 and 60 cm in the last two seasons. Soil moisture at 30 cm and soil temperature at all three depths were significant predictors of root growth. New root numbers were significantly higher in 140 Ruggeri than the other rootstocks. To the depth studied, 140 Ruggeri roots were evenly distributed from the topsoil down, whereas the majority of roots of Schwarzmann and Shiraz were located at intermediate depths in the 10–40 cm ad 20–40 cm zones respectively, while Ramsey roots were found at 20 cm or below. Depending on genotype, root growth occurred across several phenological stages but tended to peak at flowering. In some years we observed root growth in early and late winter at rates exceeding that of autumn, and this was associated with warmer temperatures during this period. In general, the seasonal dynamics of root growth attributes were found to be influenced by abiotic factors, but mainly determined by genotype. The insights gained from this study can help us better understand the interplay between rootstock, environment, and management, and predict how different rootstock genotypes may perform under changing climatic conditions. [ABSTRACT FROM AUTHOR]

Cluster thinning was performed on vines of the Syrah variety eight days before the véraison (CTBV) and after the completion of the véraison (CTAV) in the 2019 and 2021 vegetation periods. The differences in physiological and chemical properties between the grapes were investigated to which cluster thinning was applied at two different times and those without cluster thinning. According to the research results, CTBV was more effective in the berry fresh weight, dry weight, berry volume, skin weight, skin surface, cluster width, cluster length, cluster weight, and cluster volume parameters than CTAV. Likewise, the levels of total phenolic compounds, total anthocyanins, and antioxidant capacity increased by 9%, 27%, and 30%, respectively, compared to the control group without cluster thinning. Among the phenolic compounds, trans-resveratrol showed the highest increase of 38%, and petunidin-3-glucoside increased the most (12%) among anthocyanins. [ABSTRACT FROM AUTHOR]

BACKGROUND: The wine sector is constantly evolving, in order to adapt to consumer tastes. The organoleptic characteristics in wines are the main factors to obtain quality wines. Proanthocyanidins (PAs) are responsible in an important way for positive aspects in quality wines, such as body and color stability in red wines, but they are also responsible for sensory characteristics that can be negative for their quality when found in excessive concentrations. One strategy to improve grapevines and wines is to obtain new varieties, so our research institute has been selecting some of them from direct crosses between Monastrell and other considered premium varieties such as Cabernet Sauvignon and Syrah. RESULTS: A quantitative analysis in grapes, seeds and wines was carried out during three consecutive seasons (2018, 2019 and 2020) in order to characterize PAs composition and concentration in the following new varieties: MC80 (Monastrell × Cabernet Sauvignon), MC98, MC4, MC18 and MS10 (Monastrell × Syrah). Other aspect to study was the extraction capacity of the different new varieties of PAs during maceration process into must/wine. CONCLUSION: In general, the results showed higher concentrations in PAs in most crosses for the three seasons studied compared to Monastrell variety. It was remarkable that a higher concentration of epigallocatechin was found in most of the wines elaborated with the crosses, being a positive aspect from an organoleptic point of view, since this compound provides softness to the wines. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A number of publications deal with the influence of global warming on the chemical composition and sensory properties of grapes and wines. High-temperature values shorten the time needed for grape harvesting. All parts of the berries cannot reach full ripeness and the sugar concentration in the grapes increases. The acidity of the grapes often decreases, which is accompanied by an undesirable increase in pH. All this leads to harvesting the grapes before the berries have reached their full technological maturity, which refers mainly to the skin and the seeds. The insufficient ripeness of the grapes affects the chemical composition and the quality of the wine. The wine does not have the required color intensity. With a long maceration, there is a risk of increased extraction of bitter tannins. In this situation, oenologists must apply the technological procedure used in conditions of incompletely ripened grapes, or wait for the grapes to fully ripen and then apply technological procedures to reduce alcohol content and pH. Thus, the variability of the climate from year to year affects the quality of the grapes and consequently the quality of the wine. [ABSTRACT FROM AUTHOR]

This is the first viral metagenomic analysis of grapevine conducted in Mexico. During the summer of 2021, 48 plants displaying virus-like symptoms were sampled in Queretaro, an important grapevine-producing area of Mexico, and analyzed for the presence of viruses via high-throughput sequencing (HTS). The results of HTS were verified by real-time RT-PCR following a standardized testing scheme (Protocol 2010). Fourteen different viruses were identified, including grapevine asteroid mosaic-associated virus (GAMaV), grapevine Cabernet Sauvignon reovirus (GCSV), grapevine fanleaf virus (GFLV), grapevine fleck virus (GFkV), grapevine Pinot gris virus (GPGV), grapevine red globe virus (GRGV), grapevine rupestris stem pitting-associated virus (GRSPaV), grapevine rupestris vein feathering virus (GRVFV), grapevine Syrah virus 1 (GSyV-1), grapevine virus B (GVB), and grapevine leafroll-associated viruses 1, 2, 3, 4 (GLRaV1, 2, 3, 4). Additionally, divergent variants of GLRaV4 and GFkV, and a novel Enamovirus-like virus were discovered. This is the first report of GAMaV, GCSV, GLRaV4, GPGV, GRGV, GRVFV, and GSyV-1 infecting grapevines in Mexico; the impact of these pathogens on production is unknown. [ABSTRACT FROM AUTHOR]

Crossbreeding programs allow the selection of new genotypes with better agronomic and oenological properties for the production of quality wine, and allow the development of a more sustainable form of viticulture. This paper describes the white genotype 'Calblanque', and the red genotypes 'Calnegre', 'Gebas' and 'Myrtia', the first wine grape varieties registered by the Instituto Murciano de Investigación y Desarollo Agrario y Medioambiental (IMIDA) as commercial varieties after confirming the winemaking quality of their grapes in a semi-arid climate with high temperatures. These new varieties have recently been authorized for winemaking in the Region of Murcia. 'Calblanque', 'Calnegre' and 'Gebas' were obtained from crosses between 'Monastrell' and 'Cabernet Sauvignon', and 'Myrtia' from crosses between 'Monastrell' and 'Syrah'. The red genotypes were selected for their phenolic quality—which was very superior to that of the parentals—and for their different harvest dates that allow a staggered harvest and their cultivation in different areas. 'Calblanque' was selected for its good balance of acidity and aromatic profile. The attributes of these new varieties could allow their better adaptation to the effects of climate change on grape and wine quality in warm areas. [ABSTRACT FROM AUTHOR]

The disruptive effect exerted by high-power ultrasound (US) on grape cell walls is established as the reason behind the chromatic, aromatic and mouthfeel improvement that this treatment causes in red wines. Given the biochemical differences that exist between the cell walls of different grape varieties, this paper investigates whether the effect of the application of US in a winery may vary according to the grape variety treated. Wines were elaborated with Monastrell, Syrah and Cabernet Sauvignon grapes, applying a sonication treatment to the crushed grapes using industrial-scale equipment. The results showed a clear varietal effect. The wines made with sonicated Syrah and Cabernet Sauvignon grapes showed an important increase in the values of color intensity and concentration of phenolic compounds, and these increases were higher than those observed when sonication was applied to Monastrell crushed grapes, whereas Monastrell wines presented the highest concentration in different families of polysaccharides. These findings correlate with the differences in the composition and structure of their cell walls since those of Monastrell grapes presented biochemical characteristics associated with a greater rigidity and firmness of the structures. [ABSTRACT FROM AUTHOR]

Wine producers perform early wine quality prediction based on berry morphology, the taste of the berry and the measurement of basic chemical parameters. Incorporating analysis on grape and wine volatiles could potentially achieve a more accurate prediction of wine quality, but forming these models requires careful selection of grapes, controlled fermentations, and standardised quality assessment. Here, we present 3 models for the prediction of quality in Shiraz wine. Modelling was performed by general regression analysis with 4-fold cross-validation: Model 1 (R2 = 99.97% and 4-foldR2 = 97.61%) for prediction of wine quality from wine volatiles, Model 2 (R2 = 99.89% and 4-foldR2 = 98.42%) for early prediction of wine quality from free-bound and glycosidically bound grape volatiles, and Model 3 (R2 = 91.62% and 4-foldR2 = 80.21%) for the prediction of wine quality from free grape volatiles only. The accuracy of these models presents an advancement in the early prediction of wine quality and provides a valuable tool to assist grape growers and winemakers to support the understanding of quality in the vineyard to better direct scarce resources. [ABSTRACT FROM AUTHOR]

Adaptation strategies in the wine sector consist of the use of cultural techniques to limit damages caused by climate change, using, among other resources, varieties better adapted to the scenarios of abiotic stress exacerbation, namely water and thermal stress, as well as those more tolerant to heatwaves. With the intention to determine the aromatic characterization of ten monovarietal wines produced from cultivars with high productive performance in a global warming scenario ('Petit Verdot', 'Marselan', 'Merlot', 'Touriga Franca', 'Syrah', 'Vinhão', 'Bobal', 'Preto Martinho', 'Trincadeira', and 'Alicante Bouschet'), grown in Esporão vineyard (Alentejo, Portugal) and submitted to deficit irrigation (Ks ± 0.5), their aromatic character has been analyzed. Each grape variety was vinified at a small scale, in duplicate, and the wines were evaluated by a sensory panel, which rated several sensory attributes (visual, olfactory, and gustatory). Sensory analysis revealed a discrete appreciation for the monovarietal wines tasted, showing a differentiation at the olfactory level that was not too marked, although present, between the samples. The free volatile compounds were analysed using gas chromatography-olfactometry (GC-O), identified using a gas chromatography-mass spectrometry (GC-MS) technique and semi-quantified using the gas chromatography-flame ionization detector (GC-FID) technique. Based on the interpolation of the results of the various statistical analyses carried out, 49 probable odor active compounds (pOACs) were identified and based on the odor activity values (OAVs), 24 of them were recognized as odor active compounds (OACs) originated mainly during the fermentation processes. An aromatic characterization of the varieties has been proposed. [ABSTRACT FROM AUTHOR]

Background and Aims. Shiraz (Syrah) is a dark-skinned cultivar of the wine grape Vitis vinifera that forms the basis of some of the world's most iconic wines. Worldwide, Shiraz is the fourth most planted grapevine cultivar; however, it represents the most planted cultivar in Australia. Given the importance of Shiraz to worldwide wine production, this study aimed to produce a reference genome for this cultivar while investigating the unique genetic variants and ancestral origins of this iconic variety. Methods and Results. Long-read ONT data were selected to produce a highly contiguous genome assembly for Shiraz. Phylogenetic reconstruction using high-quality genome assemblies for wine grape cultivars provided further support of a kinship between Shiraz and Pinot Noir. Harnessing long-read data, transposable element insertions potentially affecting gene function were characterized in Shiraz and assessed relative to other cultivars. This revealed a heterogenous landscape of transposon insertion points across cultivars and uncovered a specific combination of allelic variants at the VviTPS24 terpene synthase locus. Conclusions. This establishment of a Shiraz genome provides a detailed view of the genetics that underpin this cultivar, including the discovery of a specific combination of VviTPS24 variants, which when combined with appropriate environmental triggers may allow Shiraz to produce high levels of rotundone, the aroma compound responsible for the distinctive peppery characteristics of this cultivar. Significance of the Study. The availability of a reference genome for Shiraz expands the pool of genomes available for wine grapes while providing a foundation resource for whole-genome studies involving this iconic cultivar, including intracultivar variant identification and transcriptomic studies using a matching reference genome. [ABSTRACT FROM AUTHOR]

Background and Aims. Shiraz disease (SD) is a viral disease associated with Grapevine virus A that causes significant yield loss in economically important grape cultivars in Australia such as Shiraz and Merlot. Current diagnostic methods are time-consuming and costly. This study evaluates an alternative methodology using visible remote sensing imagery to detect SD in Shiraz grapevines. Methods and Results. High-resolution visible remote sensing images were captured of Shiraz grapevines in two South Australian viticultural regions over two seasons. The projected leaf area (PLA) of individual grapevines was estimated from the images. Virus-infected vines had significantly lower PLA than healthy vines in the early season but fewer difference after veraison. The lower PLA was only observed in grapevines coinfected with grapevine leafroll-associated viruses (GLRaVs) and Grapevine virus A (GVA). Shiraz vines infected with either GLRaVs or GVA had similar PLA to healthy vines. Conclusions. High-resolution RGB remote sensing technology has the potential to rapidly estimate SD infection in Shiraz grapevines. Our observations of shoot devigouration only in coinfected vines calls into question the etiology of SD. Further validation of the PLA technique incorporating different regions, seasons, cultivars, and combinations of viruses is needed for improving the robustness of the method. Significance of the Study. This preliminary study presents a new rapid and low-cost surveillance method to estimate SD infections in Shiraz vineyards, which could significantly lower the cost for growers who conduct on-ground SD visual assessments or lab-based tissue testing at the vineyard scale. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects of cluster thinning and severe shoot trimming on berry and wine composition and wine sensory characteristics of Merlot variety, in the context of climate change challenges related to grapevine ripening and the corresponding high alcohol content in wine. In two seasons, two different crop sizes were obtained via cluster thinning and combined in a two-factorial design with severe shoot trimming (SST) and its respective high canopy control (HC). In both seasons, cluster thinning (CT) resulted in higher Brix in grape juice and higher alcohol in wine than full crop size (FC), whereas SST obtained lower values than HC. Total anthocyanins and phenolics in wine were increased by CT, whereas SST had no any significant effect on wine's phenolic content. Several sensory characteristics of wine were positively affected by CT in both seasons, including aroma intensity, wine body and overall wine quality, whereas SST wines were in one season characterized by increased perception of vegetal aroma, acidity and bitterness, and decreased perception of body, persistency and taste balance. Our results demonstrate that practices which affect the leaf area to fruit ratio have a major impact on wine sensorial characteristics, concluding that their choice should be based on the desired wine style. [ABSTRACT FROM AUTHOR]

Water kefir grains cannot grow in milk. Therefore, the aim of this study was to investigate whether water kefir grains can show activity in demineralized whey, an environment containing lactose as a carbon source. The physicochemical, microbiological and sensory properties of water kefir prepared from demineralized whey containing 2% and 5% lactose and raisins or grape juice from two grape varieties (Dimrit and Shiraz) were investigated. It was found that the protein content of the water kefir increased significantly (p < 0.05), especially when grape juice was added. The total soluble solids and viscosity of the samples with grape addition increased significantly (p < 0.05). Total phenolic content and antioxidant capacity increased significantly with grape addition (p < 0.05), with the effect of Shiraz grape being more pronounced. In general, it was found that the content of K, P, Na, Ca and Mg was higher in the samples with grape addition. The sensory properties of water kefir made from dWhey with 2% lactose and grape juice were better. It was also confirmed that viability of water kefir microbiota is better in water kefir drink made from dWhey with 2% lactose due to higher pH value in comparison to dWhey with 5% lactose. [ABSTRACT FROM AUTHOR]

Rootstock can significantly alter the concentration of methoxypyrazines (MPs) in the bunch stem (rachis) of Vitis vinifera L. cv. Cabernet Sauvignon and Shiraz, which has implications for winemaking and wine style. The distribution of MPs across the rachis is an important consideration, but such information was not available. This study aimed to address this research question by comparing MP concentrations in different rachis components throughout grape maturation and in the absence of ambient light. Shiraz and Cabernet Sauvignon bunches were sampled throughout development, segmented into four components (peduncle, top rachis, bottom rachis, and pedicel), and 3-isobutyl-2-methoxypyrazine (IBMP) was quantified in each. For both cultivars, IBMP showed a negative correlation with grape maturity, with concentrations in pedicel at harvest being significantly higher than other rachis components. Additionally, light exclusion significantly increased IBMP concentrations in all rachis segments. The concentration of IBMP varied significantly between different rachis components. The greatest concentrations were measured in the pedicel, which also contributed the largest proportion among the components to total rachis by weight. Due to elevated IBMP concentrations in rachis and the difficulties in excluding matter other than grape from a fermentor, the presence of pedicel during fermentation could produce Shiraz and Cabernet Sauvignon wines with higher concentrations of MPs, thereby potentially increasing vegetal sensory characteristics. [ABSTRACT FROM AUTHOR]

The quality of wine grapes and wine depends on their content of phenolic compounds. Under commercial conditions, the phenolic maturity of grapes is mostly achieved by applying abscisic acid analogues. Some Ca forms represent a cost-effective alternative for these compounds. In this study, 'Shiraz' vines (veraison of 90%) were sprayed with CaCO3-rich residues from the cement industry (4.26 g of Ca per L). Fruit from treated and untreated vines was harvested 45 days after CaCO3 spraying and evaluated for quality. The fruit was vinified, and the obtained wines were bottled and stored in darkness for 15 months at 20 °C. Wines were evaluated for quality after storage. The evaluation of grape and wine quality included the content of phenolic compounds and antioxidant capacity. The treatment with CaCO3 did not affect the ripening rate of grapes. However, the treatment improved the fruit yield as well as the color development, the content of phenolic compounds, and antioxidant capacity of grapes and wine. The treatment favored especially the accumulation of malvidin-3-O-glucoside, pelargonidin-3-O-glucoside, caftaric acid, caffeic acid, trans-cinnamic acid, quercetin, catechin, epicatechin, resveratrol, and the procyanidins B1 and B2. Wine made with treated fruit was of higher quality than that of control fruit. [ABSTRACT FROM AUTHOR]

Fungal pathogens involved in grapevine trunk diseases (GTDs) may infect grapevines throughout their lifetime, from nursery to vineyard, via open wounds in stems, canes or roots. In vineyards, pruning wound protection products (PWPPs) offer the best means to reduce the chance of infection by GTD fungi. However, PWPPs may affect non-target microorganisms that comprise the natural endophytic mycobiome residing in treated canes, disrupting microbial homeostasis and indirectly influencing grapevine health. Using DNA metabarcoding, we characterized the endophytic mycobiome of one-year-old canes of cultivars Cabernet Sauvignon and Syrah in two vineyards in Portugal and Italy and assessed the impact of established and novel PWPPs on the fungal communities of treated canes. Our results reveal a large fungal diversity (176 taxa), and we report multiple genera never detected before in grapevine wood (e.g., Symmetrospora and Akenomyces). We found differences in mycobiome beta diversity when comparing vineyards (p = 0.01) but not cultivars (p > 0.05). When examining PWPP-treated canes, we detected cultivar- and vineyard-dependent alterations in both alpha and beta diversity. In addition, numerous fungal taxa were over- or under-represented when compared to control canes. Among them, Epicoccum sp., a beneficial genus with biological control potential, was negatively affected by selected PWPPs. This study demonstrates that PWPPs induce alterations in the fungal communities of grapevines, requiring an urgent evaluation of their direct and indirect effects on plants health with consideration of factors such as climatic conditions and yearly variations, in order to better advise viticulturists and policy makers. [ABSTRACT FROM AUTHOR]

Azerbaijan is one of the ancient wine-growing country, and it is famous by its rich assortment of local grapes. Historically, in our country well-known brand wines have been prepared from aboriginal red grape varieties. Among them, we can mention branded Kurdamir kagoru, Shamakhi kagoru, Madasa and Khindogni natural wines, etc. wines made from such autochthonous grape varieties won the favor of consumers with their unique physical-chemical and organoleptic characteristics. In line with it, in recent years, to the country introduced a number of valuable grape varieties such as Merlot, Cabernet Sauvignon, Syrah and others. It is actually relevant comparative evaluation of such varieties cultivated in local conditions, including red ones. During the ripening of the studied grape varieties, the amount of sugars ranged between 197 and 265 g/dm³, titratable acids from 4.5 to 7.7 g/dm³, and active acidity between 3.08 and 3.61. The mass concentration of sugars in the Xindogni grape variety was 197 g/dm³ on average. The varieties were in ascending order of the mass concentration of sugars: Madrasa 222 g/dm³, Cabernet-Sauvignon 226 g/dm³, Merlot 240 g/dm³, and Shirvanshahi 265 g/dm³ . One of the important indicators determining the quality of raw materials is known to be the sugar-acid potential, in other words, a glucoacidometric index (GAI). In the studied varieties, the GAI varied from 3.0 to 5.7. This index was higher in the Shirvanshahi variety (5.7), medium in Madrasa (4.9) and Cabernet Sauvignon (4.8), and lower in the Xindogni (3.0) and Merlot (3.1) grape varieties. Delphinidin, cyanidin, peonidin, and malvidin anthocyanidins were found in skin hydrolysates. The amount of resveratrol in the skin, seed, and leaf was 0.75-8.25mg/kg, 0.31-5.7mg/kg, and 0.01- 0.25mg/kg, respectively, depending on varieties and years. Local grape varieties had a noticeable level of aromatic alcohol content and were not at all inferior to the famous Cabernet Sauvignon grape variety. Aromatic alcohols such as β-phenylethanol, β-phenoxyethanol, and phenylcarbinol were among the compounds of importance for Kagortype wines. A comparison of their quantity showed that the amount of these compounds in the Madrasa grape variety was more than in the other two grape varieties. [ABSTRACT FROM AUTHOR]

Climatic factors play a key role in determining the suitability of a given region for specific cultivars and wine types and the responses of individual grapevine cultivars to climate are of utmost importance for activity planning and decision making in viticulture. The study investigated the effect of climate conditions from 2006 till 2018 on the performance of cv. Syrah cultivated in two vineyards in Lebanon; Kanafar (at 1,020 m.a.s.l) and Mansoura (at 850 m.a.s.l). Cluster analysis based on climate indicators divided years into two clusters; in Kanafar (cluster 1: 2006-2015, cluster 2: 2016-2018) and in Mansoura (cluster 1: 2006 to 2008, cluster 2: 2009 to 2018). Solar radiation (May-June) and average wind speed (July-August-September) were the most influential predictors in Kanafar and Mansoura, respectively. In Kanafar, average yield and weight of 200 berries decreased by 21% and 22.7 g respectively in cluster 2, but in Mansoura only average yield increased by 3.7% in cluster 2. Total soluble solids and titratable acidity were not significantly affected by the shift in climate conditions at both vineyards, however total anthocyanin potential was significantly lower in Kanafar (by 114.2 mg kg-1) and higher in Mansoura (by 353.4 mg kg-1) in cluster 2. Total polyphenolic richness was only affected in Kanafar (reduction by 42 mg GAE g-1 in cluster 2). Syrah performance was more negatively affected by the changing climate conditions at Kanafar rather than Mansoura vineyards and it seems to better adapt to climate conditions of Mansoura overcoming the shift in climate that occurred after 2008 there. [ABSTRACT FROM AUTHOR]

BACKGROUND: In todays' society, the rapid development of the wine industry and the improvement of peoples' living standards make people pay more and more attention to wine grape quality. OBJECTIVE: To evaluate the wine grape varieties in Northeast Chinas' grape growing regions for better wine grape quality, we evaluated the quality of different varieties of wine grapes. METHODS: The grape varieties 'Hassan' 'Zuoshaner' 'Beibinghong' 'Zuoyouhong' 'Beta' 'Shuanghong' 'Zijingganlu' 'Cabernet Sauvignon' and 'Syrah' were planted in the grape growing area of Jilin, Northeast China, were used as the subjects of this study. The grape berries were analyzed and tested for morphological indicators, basic physicochemical indicators, color, and phenolic and aromatic composition. RESULTS: According to lab results, 'Hassan' contained the highest amount of total phenolics; 'Zuoyouhong' had the highest solids and total sugar content; 'Shuanghong' had the most elevated total acid and anthocyanin content; 'Zijngganlu' had the highest tannin content and acid fixation ratio; Seventy-one volatile compounds were detected in nine grape varieties. CONCLUSIONS: Each of the nine grape varieties has a distinctive flavor, and because of this, grape processing products with regional flavors can be created. The same offer valuable data for future scientific grape resource collection, conservation, and exploitation. [ABSTRACT FROM AUTHOR]

Shiraz disease (SD) is an economically important virus-associated disease that can significantly reduce yield in sensitive grapevine varieties and has so far only been reported in South Africa and Australia. In this study, RT-PCR and metagenomic high-throughput sequencing was used to study the virome of symptomatic and asymptomatic grapevines within vineyards affected by SD and located in South Australia. Results showed that grapevine virus A (GVA) phylogroup II variants were strongly associated with SD symptoms in Shiraz grapevines that also had mixed infections of viruses including combinations of grapevine leafroll-associated virus 3 (GLRaV-3) and grapevine leafroll-associated virus 4 strains 5, 6 and 9 (GLRaV-4/5, GLRaV-4/6, GLRaV-4/9). GVA phylogroup III variants, on the other hand, were present in both symptomatic and asymptomatic grapevines, suggesting no or decreased virulence of these strains. Similarly, only GVA phylogroup I variants were found in heritage Shiraz grapevines affected by mild leafroll disease, along with GLRaV-1, suggesting this phylogroup may not be associated with SD. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated that the application of ultrasounds to crushed grapes improves the chromatic and sensory characteristics of the resulting wines by facilitating the extractability of compounds from grapes to the must-wine. The objective of this work was to determine whether the application of ultrasounds to grapes of different maturity levels or different sanitary status leads to the same positive outcome as regards chromatic characteristics, phenolic and aroma compounds as well as sensory properties. The results showed that, independent of grape ripening or sanitary status, the application of ultrasounds to Syrah crushed grapes leads to wines with better chromatic characteristics at the moment of bottling, increasing colour intensity, total phenol content and tannin concentration up to 12%, 18% and 43%, respectively, in the wines from less ripen grapes and 13%, 23% and 30% in the wine from partially rotten grapes. The concentration of volatile compounds was less affected by sonication than the chromatic characteristics, with small decreases in the main families of volatile compounds, although the sensory analysis showed clear differences between control wines and those made from sonicated grapes, which were generally preferred and score higher for most of the sensory parameters evaluated. [ABSTRACT FROM AUTHOR]

Spectroscopy is a widely used technique that can contribute to food quality assessment in a simple and inexpensive way. Especially in grape production, the visible and near infrared (VNIR) and the short-wave infrared (SWIR) regions are of great interest, and they may be utilized for both fruit monitoring and quality control at all stages of maturity. The aim of this work was the quantitative estimation of the wine grape ripeness, for four different grape varieties, by using a highly accurate contact probe spectrometer that covers the entire VNIR–SWIR spectrum (350–2500 nm). The four varieties under examination were Chardonnay, Malagouzia, Sauvignon-Blanc, and Syrah and all the samples were collected over the 2020 and 2021 harvest and pre-harvest phenological stages (corresponding to stages 81 through 89 of the BBCH scale) from the vineyard of Ktima Gerovassiliou located in Northern Greece. All measurements were performed in situ and a refractometer was used to measure the total soluble solids content (°Brix) of the grapes, providing the ground truth data. After the development of the grape spectra library, four different machine learning algorithms, namely Partial Least Squares regression (PLS), Random Forest regression, Support Vector Regression (SVR), and Convolutional Neural Networks (CNN), coupled with several pre-treatment methods were applied for the prediction of the °Brix content from the VNIR–SWIR hyperspectral data. The performance of the different models was evaluated using a cross-validation strategy with three metrics, namely the coefficient of the determination ( R 2 ), the root mean square error (RMSE), and the ratio of performance to interquartile distance (RPIQ). High accuracy was achieved for Malagouzia, Sauvignon-Blanc, and Syrah from the best models developed using the CNN learning algorithm ( R 2 > 0.8 , RPIQ ≥ 4 ), while a good fit was attained for the Chardonnay variety from SVR ( R 2 = 0.63 , RMSE = 2.10 , RPIQ = 2.24 ), proving that by using a portable spectrometer the in situ estimation of the wine grape maturity could be provided. The proposed methodology could be a valuable tool for wine producers making real-time decisions on harvest time and with a non-destructive way. [ABSTRACT FROM AUTHOR]

The influence of terroir in determining wine sensory properties is supported by the specific grape microbiome and metabolome, which provide distinct regional wine characteristics. In this work, the metabolic composition of grapes, must and wine of the Syrah grape variety cultivated on two sites in the same region was investigated. Concomitantly, a sensorial analysis of the produced wines was performed. Ultra-high-resolution liquid chromatography coupled with tandem mass spectrometry (UHPLC-Q-ToF-MS/MS) was applied to identify grape and wine metabolites. Untargeted metabolomics was used to identify putative biomarkers for terroir differentiation. More than 40 compounds were identified, including 28 phenolic compounds and 15 organic acids. The intensity evolution of the analyzed chemical compounds showed similar behavior during the fermentation process in both terroirs. However, the metabolic analysis of the grape, must and wine samples enabled the identification of an anthocyanin, chrysanthemin, as a putative biomarker of terroir 1. The overall sensorial quality of the wines was also evaluated, and according to the hitherto reported results, the wines from site 1 scored better than the wines from site 2. The results highlight the potential of metabolomics to assess grape and wine quality, as well as terroir association. [ABSTRACT FROM AUTHOR]

Syrah decline, first identified in Southern France in the 1990s, has become a major concern in the global grape and wine industry. This disease mainly affects Syrah (Shiraz) grapevines. Characteristic symptoms include the bright and uniform reddening of leaves throughout the canopy in late summer or early fall; the appearance of abnormalities on the trunk, mainly at the graft union (swelling, pits, grooves, and necrosis); and a reduction in vine vigor, yield and berry quality. Diseased vines may die a few years after disease onset. Damages to the vine are even more pronounced in cool climate regions such as Ontario (Canada), where the affected vines are subjected to very cold and prolonged winters, leading to large numbers of vine deaths. Despite the extensive efforts of the global grape research community over the past few decades, the etiology of this disease remains unclear. In this study, we conducted extensive analyses of viruses in declining Syrah vines identified in commercial vineyards in the Niagara region (Ontario, Canada) through high-throughput sequencing, PCR, RT-PCR and the profiling of genetic variants of select viruses. Multiple viruses and viral strains, as well as three viroids, were identified. However, an unequivocal causal relationship cannot be established between Syrah decline and any of these viruses, although the possibility that certain virus or genetic variants, or both in combination, may contribute to the disease cannot be excluded. Gleaning all information that is available to date, we feel that the traditional approach and an insistence on finding a single cause for such a complex disorder in a woody perennial fruit crop involving grafting will prove to be futile. We hope that this study offers new conceptual perspectives on the etiology of this economically important but enigmatic disease complex that affects the global grape and wine industry. [ABSTRACT FROM AUTHOR]

Simple Summary: In this paper the phenolic composition of Syrah and Chardonnay grape pomaces was studied to assess their antioxidant and prooxidant properties, and their effect on melanoma cancer cells. The phenolic composition of Syrah and Chardonnay grape pomaces was studied to assess their antioxidant and prooxidant properties. Polyphenols were extracted by a "green" hydroalcoholic solvent (ethanol/water 1:1 v/v), and a detailed chemical and electrochemical characterization of the phenolic compounds was performed. The antioxidant and prooxidant capacity of the pomace was first studied by cyclic voltammetry (CV) and other reference analytical assays, then with biological tests on B16F10 metastatic melanoma cancer cells. Electrochemical data showed that, when a +0.5 V potential was applied, a low to moderate antioxidant capacity was observed. MTT test showed an increasing viability of melanoma cells, after treatments at low concentration (up to 100 μg/mL) and for a short time (6 h), but when cells were treated with higher doses of extract (≥250 μg/mL for 12/24 h), their viability decreased from 25 to 50% vs. control, depending on treatment time, dose, and extract origin. A stronger prooxidant activity resulted when 250 μg/mL of extract was combined with non-toxic doses of H2O2; this activity was correlated with the presence of copper in the extracts. This study shows the potential of winemaking by-products and suggests the opportunity to exploit them for the production of cosmeceuticals, or for combined therapies with approved anticancer drugs. [ABSTRACT FROM AUTHOR]

One of the biggest problems with the use of traditional fining agents is that some of them present allergenic characteristics or are not suitable for vegan consumers due to their animal origin. An alternative to these traditional proteinaceous agents could be cell walls from grape pulp. This material could be used to modify the final phenolic concentration of a wine due to its affinity for phenolic compounds. In this study, the ability of freeze-dried grape pulp fiber, rich in pulp cell walls, to act as a fining agent was analyzed in wines from three different varieties: Cabernet Sauvignon, Syrah, and Monastrell. After the use of this material, the wine chromatic characteristics and total tannin concentration were analyzed by spectrophotometric and chromatographic techniques. In addition, the wines were contaminated with ochratoxin A and histamine to check whether this material could also be a tool for removing these wine contaminants. The pulp fiber presented a high capacity to retain phenolic compounds, especially tannins; however, there were differences depending on the studied wine. The largest reduction in tannin concentration after fining was observed when this material was used in Cabernet Sauvignon wines (23%), whereas for Monastrell wines the reduction was lower (18.3%) and even lower for Syrah wines (14.3%). This fining agent also reduced the anthocyanin concentration of the three red wines, although to a lesser extent than the reduction observed for tannins. A really interesting result was that the addition of this fining agent reduced the concentration of ochratoxin A by 50% in all the studied wines. [ABSTRACT FROM AUTHOR]

BACKGROUND: Vitis vinifera L. cv. Syrah grapevines in most Chinese viticulture regions generally have compact clusters that increase the susceptibility to diseases and inhibit coloration of the inner berries. Gibberellic acid (GA3) is a plant growth regulator that is widely used during grape cultivation to elongate the rachis, control fruit set, and decrease cluster compactness. In this study, Syrah grapevines were treated with GA3 before flowering in 2019 and 2020 to determine the optimal GA3 treatment concentrations and times for decreasing bunch compactness, while minimizing the negative effects on the wine grape cluster weight. RESULTS: Pre‐flowering GA3 applications at 3, 5, and 7 mg L−1, especially treatment at 20 days before flowering, decreased Syrah grape bunch compactness by decreasing the fruit set rate and promoting bunch elongation, with minimal adverse effects on the healthy grape cluster weight in both years. The 7 mg L−1 GA3 treatment at 20 days before flowering significantly increased reducing sugar, total phenolic, tannin, and total anthocyanin contents of Syrah grape berries in 2019 and 2020. Moreover, high‐performance liquid chromatography–electrospray ionization–tandem mass spectrometry, hierarchical cluster, and principal component analysis results indicated GA3 applications before flowering (3, 5, and 7 mg L−1) significantly affected the accumulation of different anthocyanins in Syrah grape berries. Notably, the application of 7 mg L−1 GA3 at 20 days before flowering resulted in the highest anthocyanin content. CONCLUSION: Pre‐flowering gibberellin application can decrease bunch compactness and improve the quality of Syrah grape berries. These findings reflect the potential utility of gibberellin treatments for decreasing cluster compactness and increasing the quality of wine grapes. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Precision viticulture employs various sensors for assessing nondestructively key parameters in vineyards. One of the most promising technologies for this purpose is the laser scanner sensor. Laser scanner uses the LiDAR (Light Detection And Ranging) method for the calculation of the distance from the sensor. However, the number of cultivation operations affects the credibility of sensors such as the laser scanner. The main aim of this study was to assess a laser scanner sensor at different measurement settings for estimating pruning wood parameters on two wine grape cultivars (Sauvignon Blanc and Syrah) that received different numbers of farming interventions. The experiment was conducted in the two vineyards situated in the same farm for two successive years (2014 and 2015). The results indicated that the use of a laser scanner in the Syrah vineyard presented more accurate results (r = 0.966 in 2014 and r = 0.806 in 2015) when compared to the Sauvignon Blanc one (r = 0.839 in 2014 and r = 0.607 in 2015) regarding pruning wood parameters estimation. Different measurement settings and weather conditions had different effects on the accuracy of the sensor. It can be concluded that the laser scanner is a very helpful sensor for estimating pruning wood parameters in vineyards. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spatial variation at different altitudes presented different microclimate zones. • PCA model characterized physicochemical composition and phenolic compounds of grape. • MA, TTC, TPC, TA, TAC and skin thickness separated grape quality at various altitudes. • SEM model identified the ST, DIF and DayAT affecting grape quality difference. With the increasing threat of global warming, the cultivation of wine grapes in high-altitude with cool-temperature climates has become a viable option. However, the precise mechanism of environmental factors regulating grape quality remains unclear. Therefore, principal component analysis (PCA) was utilized to evaluate the quality of wine grape (Cabernet Sauvignon) in six high-altitude wine regions (1987, 2076, 2181, 2300, 2430, 2540 m). Structural equation modeling (SEM) was applied for the first time to identify the environmental contribution to grape quality. The wine grape quality existed spatial variation in basic physical attributes (BP), basic chemical compositions (BC), phenolic compounds (PC) and individual phenols. The PCA models (variance > 85 %) well separate wine grapes from the six altitudes into three groups according to scores. The score of grapes at 2300 m was significantly high (3.83), and the grapes of 2540 m showed a significantly low score (1.46). Subsequently, the malic acid, total tannin, total phenol, titratable acid, total anthocyanin, and skin thickness were the main differing indexes. SEM model characterized the relational network of differing indexes and microclimatic factors, which showed that temperature and extreme air temperature had a greater direct effect on differing indexes than light, with great contributions from soil temperature (0.98**), day-night temperature difference (0.825*), and day air temperature (0.789**). Our findings provided a theoretical basis for grape cultivation management in high-altitude regions and demonstrated that the SEM model is a useful tool for exploring the relationship between climate and fruit quality. [ABSTRACT FROM AUTHOR]

Grape-based brandies are one of the most popular alcoholic beverages in the world. The most popular one, Cognac, comes from the Charentes region of Southwest France, and it is mostly produced from the grape variety 'Ugni Blanc'. However, wines destined for the elaboration of wine spirits also come from different white grape varieties; 'Colombard', 'Folle Blanche', 'Montils', and 'Semillon'. In this study, the possibility of using the red grape varieties 'Cabernet Sauvignon' and 'Syrah' was investigated with an emphasis on the change of volatile compounds during the production process. During production, some specific volatile compounds such as 2-hexenal, 3-octanone, isopropyl myristate, ethyl palmitate, ethyl oleate, phenethyl acetate, 1-hexanol, and β-damascenone could be attributed to the primary aroma generated from the grape varieties. During the vinification and fermentation process, the development of ethyl hexanoate, ethyl octanoate, 3-methylbutanol, acetic acid, and octanoic acid occurred. Finally, 3-methylbutanol and predominant esters, ethyl hexanoate, ethyl octanoate, ethyl decanoate, and ethyl laurate, were generated during the distillation and maturation process. The composition and concentration of determined predominant esters in produced brandies suggest that both brandies have volatile profiles comparable to some of the world's most popular brandies. [ABSTRACT FROM AUTHOR]

While there is evidence of consumers' interest in wine sustainability, acceptance of innovations in wine production is not guaranteed. The current study addresses this issue by analyzing consumers' acceptance of fungus-resistant grape (FRG) wines, a sustainable innovation that can substantially reduce the need for chemical inputs in viticulture. To do so, by means of an online survey including large samples of regular wine drinkers in Italy (N = 752), the UK (N = 858) and the USA (N = 856), the study compares individuals' preferences for conventional wines with preferences for FRG wines. The study also explores whether FRG wine acceptance is influenced by informal or formal purchase occasion, by different types of information regarding the product, and by individual attitudinal characteristics. The findings show a general acceptance of FRG wines among consumers. In particular, consumers' preferences for FRG wines on formal occasions are not significantly different from their preferences for conventional wine, whereas on informal occasions, consumers prefer FRG wines over conventional wines. Regarding the impact of information on participant choice, participants informed about the potential effects of FRG on sensory wine characteristics had lower preferences for FRG wines than those who read an information script regarding crop biodiversity. Last, individuals' sustainability concerns and food technology neophobia had positive and negative influences on FRG acceptance, respectively. Overall, this research provides wineries, nurseries and policy-makers with important insights concerning the market potential of FRG wines in three key markets. [ABSTRACT FROM AUTHOR]

Grapevine (Vitis vinifera L.) is a plant containing many phenolic compounds, mostly distributed in the peel, pulp, and seeds. This study evaluates the centesimal composition and bioactive compounds in Shiraz grape (Vitis vinifera) peels using spectrophotometric and UHPLC techniques and develops different formulations of compound powders from the peels and arrowroot using conventional drying technology. The results demonstrate that Shiraz grape skin contains significant amounts of insoluble fiber (15.3%), phenolics (157.09 ± 6.96-149.11 ± 9.27 mg GAE g-1), and flavonoids (0.75 ± 0.50-2.00 ± 0.50 mg QE g-1), with excellent antioxidant capacity observed in the alcoholic extracts. The phenolic content in the developed powdered compounds ranged from 128.32 to 139.70 mg GAE g-1. In general, the compounds showed good antioxidant capacity (IC50 = 0.17 to 0.19 μg mL-1). According to the chromatographic evaluation, it was possible to quantify gallic acid, catechin, and epicatechin, the latter of which was found in the largest quantities in the six formulations. The EV5 formulation was the most efficient in terms of phenolic compounds and protein amounts. This formulation's composition and low cost could make it viable for use in the food industry. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The aim of the present study is to apply a mathematical approach (correlation and factor analysis) to assess the similarity and remoteness of the impact of climate indicators in some clones of Syrah variety. Their grouping is based on phenological, and technological indicators. Temperatures during the individual experimental years have a dominant influence on the quality of grapes in the individual clones included in the study. As a result of analysis, correlations were established between phenological indicators like follow: sap, bud burst, first leaf separation, flowering, fruit set, veraison, ripeness and technological ones - average mass per bunch, normal and undeveloped berries, percent of clusters and damaged berries, average bunch size (width and length). The phenological indicators - sap flow, flowering and fruit set "pea size" and technological - undeveloped berries, damaged berries have high factor weights in the first component, which is a summary of these indicators, with the highest relative weight in the vines grouping. [ABSTRACT FROM AUTHOR]

The present study sought to characterize the microparticles obtained from the co‐encapsulation of anthocyanins extracted from red grape skins and α‐tocopherol via spray drying. Briefly, grape skin extract was homogenized with gum arabic, Tween 80, and different concentrations of α‐tocopherol. Anthocyanin content, antioxidant activity, total phenolic content, α‐tocopherol concentration, color, hygroscopicity, morphology, and the Fourier transform infrared spectroscopy (FTIR) results of each treatment were analyzed. The highest concentration of α‐tocopherol led to the highest total phenolic content, and the lowest hygroscopicity and anthocyanin content. Intermediate concentrations of α‐tocopherol resulted in an increased incidence of microparticles with smooth surface and elevated antioxidant activity. The FTIR spectra verified the efficacy of the process, showing characteristic bands of the co‐encapsulated compounds. Overall, α‐tocopherol concentrations between 1.5% and 2.0% (w/w) led to good powder properties (hygroscopicity, total phenolic content and antioxidant activity), generating further research interest to evaluate the use of α‐tocopherol in foods. Practical applications: The development of products containing bioactive compounds that offer benefits to human health have gained a lot of attention. In this study, the co‐encapsulation of anthocyanins extracted from grape skin and α‐tocopherol by spray drying proved to be interesting as an interaction occurred between compounds, which enables the attainment of an added‐value natural product, representing an innovation in the food sector. [ABSTRACT FROM AUTHOR]