Wine Grape Varieties Research Articles

The influence of climate on varietal similarities across countries

AbstractIn recent decades, vignerons have focused more on the world's mainstream varieties than on differentiating their varietal mix. This has led countries to become more similar to each other in their mix of winegrape varieties and more varietally concentrated. What are the drivers of those changes? In this study, we focus on one of those drivers, that is, climate similarities. We estimate statistical models to quantify the potential influence of 16 climate variables on varietal similarities across countries, as well as on how their varietal mixes have become more or less similar since 2000. The results indicate not only that countries with more similar climates have more similar varietal mixes but also that in recent years countries with more similar climates have become even more similar in their mixes. This, however, does not necessarily mean that vignerons have been planting the varieties that are better adapted to their climates.Core Ideas Wine‐producing countries have become more similar and concentrated in their mix of winegrape varieties. This similarity extends particularly among countries sharing similar climatic conditions. In recent years, countries with similar climates have continued to converge in their winegrape varietal mixes. Nevertheless, vignerons have not necessarily been planting varieties that are better suited to their climates.

Exploring the Interplay of Bud Load and Pruning Type in Shaping ‘Xinomavro’ (Vitis vinifera L.) Vine Growth, Yield, and Berry Composition

‘Xinomavro’ (V. vinifera L.) is an important native red wine grape variety in Northern Greece, particularly in PDO (protected designation of origin) regions. Despite its significance, there is limited research on the effects of pruning type and severity on ‘Xinomavro’ vine physiology, yield, and berry quality across diverse environmental conditions. This study aimed to address this knowledge gap and provide growers with crucial information for optimizing vineyard management practices. The study was conducted over two consecutive years (2016 and 2017) in a vineyard in Thessaloniki, Northern Greece. Four treatments (B12: 12 buds on 6 spurs, B24: 24 buds on 12 spurs, M12: 12 buds on 2 canes, and M24: 24 buds on 4 canes) combining two bud load levels (12 or 24 count nodes) and two pruning types (short spurs or long canes) were applied to ‘Xinomavro’ vines in a complete block randomized design. The vine water status, gas exchange, canopy characteristics, yield components, and berry composition were measured. Bud load and pruning type significantly influenced vine canopy development, microclimate, and yield components. Short pruning with high bud load (B24) resulted in denser canopies and higher yields, whereas cane pruning (M12 and M24) led to more open canopies and improved berry quality indicators. Treatment effects on berry composition were inconsistent across years but showed a tendency for higher anthocyanin and total phenol content in cane-pruned vines. This study demonstrates that pruning type (short or long fruiting units) may have a greater impact on vine growth, yield, and berry composition than bud load alone in ‘Xinomavro’ vines. Cane pruning appears to be a more effective strategy for achieving vine balance and potentially improving grape quality under given experimental conditions.

Seed morphometrics unravels the evolutionary history of grapevine in France.

The cultivation of grapevines has spanned millennia, leading to thousands of varieties through exchanges, mutations, and crosses between genotypes, as well probably as gene flow from wild populations. These varieties are typically categorized by regional origin and primary use, either for wine production or fruit consumption. France, within the Western European group, hosts many of the world's renowned wine grape varieties. However, the historical development of cultivated grapevines in France and in the world remains poorly understood. This study applies morphometry on 19,377 charred and waterlogged archaeological grape pips to investigate the evolutionary history of grapevine in France over the last 10,000 years. The study compares seed outlines and lengths, corrected for taphonomic distortions, with a reference collection of 80 wild and 466 modern domestic grapevine accessions. Findings reveal a shift from wild grapevine exploitation to the expansion of domestic varieties around 600-500 BCE, coinciding with Mediterranean cultural influences and the introduction of eastern grape types. The identification of the East-Table group, a group of varieties of eastern origin for fruit consumption, indicates that grapes were also grown for food, especially in Mediterranean regions and near urban areas, alongside wine production. Early French viticulture featured a notable presence of Western European wine-type grapevines. The abundance of pips with wild-like morphology suggests early cultivation involved plants at an initial domestication stage and gene flow between introduced and wild grapevines. As viticulture spread northward, wild and Eastern morphotypes declined, leading to the dominance of Western European wine types in inner France during the Middle Ages.

Yeast Diversity in Wine Grapes from Japanese Vineyards and Enological Traits of Indigenous Saccharomyces cerevisiae Strains.

Japan has numerous vineyards with distinct geographical and climatic conditions. To the best of our knowledge, there is no comprehensive analysis of the diversity of yeasts associated with wine grapes from Japan. This study aimed to determine yeast diversity in wine grapes from four wine-producing regions in Japan and to evaluate the physicochemical characteristics of wines produced with indigenous Saccharomyces cerevisiae strains isolated from two regions. A total of 2648 strains were isolated from nine wine grape samples. MALDI-TOF MS and 26S rDNA sequence analyses revealed that the strains belonged to 21 non-Saccharomyces yeasts and 1 Saccharomyces yeast (S. cerevisiae). Non-Saccharomyces yeasts were found in high quantities and were highly distributed among the wine grape samples. Differences in the distribution of the identified yeast species were noted among the different wine grape varieties and regions. Indigenous S. cerevisiae strains of different genotypes from different regions exhibit distinct physiological traits. Our findings are expected to enhance our understanding of the local yeasts associated with Japanese vineyards and contribute to obtaining cultures that can provide region-specific organoleptic characteristics to local wines produced in Japan.

Xylem Vessel Size Is Related to Grapevine Susceptibility to Phaeomoniella chlamydospora

Grapevine trunk diseases are a threat to table- and grape-wine cultivation worldwide. Phaeomoniella chlamydospora (Pch) is a vascular fungus recognized as one of the most important pathogens associated with grapevine trunk diseases. The relationships between xylem vessel features and Pch susceptibility of 10 table- and 17 wine-grape genotypes, as well as 3 rootstocks, were investigated by image analysis of 50 µm cross-sections and artificial Pch inoculation on one-year-old vine cuttings. Vessels were grouped in the diameter classes 1–30, 31–60, 61–90, 91–120, and >120 µm. Among the table-grape varieties, ‘Sable’, ‘Timco’, and ‘Red Globe’ showed higher densities of large vessels (>120 μm) than ‘Italia’, ‘Sugar Crisp’, and ‘Sugraone’. Among the wine-grape varieties, ‘Minutolo’, ‘Montepulciano’, ‘Primitivo’ CDTa19, and ‘Verdeca’ showed higher densities of large vessels than ‘Aglianico’, ‘Nero di Troia’, ‘Sangiovese’, and ‘Susumaniello’. In the rootstocks, the vessel diameters were 50.8, 54.0, and 60.9 μm for ‘34 E.M.’, ‘140 Ruggieri’, and ‘1103 Paulsen’, in that order. For table-grape varieties, Pch was re-isolated from 13.3% for ‘Sugar Crisp’ and ‘Sugraone’ cuttings up to 93.3% for ‘Timco’. For wine-grape varieties, Pch re-isolation ranged from 51.1% (‘Bombino nero’, ‘Negroamaro’ D15, and ‘Sangiovese’) to 81.1% (‘Montepulciano’), while for the rootstocks, the values were from 33 to 51%. A principal component analysis (PCA) revealed a positive correlation between the frequencies of large vessels and Pch re-isolation. In addition, in wine grapes and rootstocks, higher Pch re-isolation frequencies in the lateral parts of cuttings were correlated (r = 0.79) to a higher frequency of large vessels. The results highlight relationships between grapevine xylem vessel sizes and susceptibility to P. chlamydospora that are worthy of further research.

Unlocking the secrets of intraspecific hybrids (Vitis vinifera L.) cold hardiness: A comprehensive study of genetic factors and trait correlations

Challenges arise in global viticulture due to low temperatures. To ensure the sustainable and high-quality development of the wine industry, it is essential to breed wine grape varieties that are not only of high quality but also possess cold hardiness. Intraspecific recurrent selection in Vitis vinifera can enhance cold hardiness while maintaining fruit quality. In this study, we used ‘Ecolly ’as an intermediary grape variety for crossing with ‘Cabernet Sauvignon’, ‘Marselan’, and ‘Dunkelfelder’, including three reciprocal crosses and a total of 1,657 intraspecific hybrids. We characterized the cold hardiness of these intraspecific hybrids and analyzed the genetic aspects of cold hardiness, ultimately identifying excellent strains with cold hardiness. Parameters like mean high-temperature exotherm (mHTE), mean low-temperature exotherm (mLTE), bound/free water ratio, water loss ratio in vitro, frost damage grades, and overall performance displayed partially normal distributions. In intraspecific hybrids, there was a maternal advantage in traits related to bound/free water ratio and water loss ratio. Some hybrid populations exhibited values for mHTE, mLTE, and water loss ratio that were lower than the low parent's values, while bound/free water ratio showed values higher than the high parent's values. Among the 1,657 intraspecific hybrids, 52 strains could bud under stress at −18 °C, and seven of these strains excelled in three important cold hardiness measures. Our study revealed that cold hardiness in V. vinifera is influenced by multiple genes and is a quantitative trait. Intraspecific hybridization can produce a small number of superior strains with enhanced cold hardiness.

Drivers of Environmental Sustainability in the Wine Industry: A Life Cycle Assessment Approach

The primary aim of this study is to conduct a comprehensive review of the existing literature to identify the most relevant environmental variables and other factors influencing the life cycle assessment of the wine industry. This research seeks to determine whether the type of wine significantly impacts the carbon footprint and to highlight the importance of production strategies over wine typology or grape variety in reducing greenhouse gas emissions. This review encompasses an extensive analysis of previous studies on the environmental impact of wine production. This method involves synthesizing findings from life cycle inventory assessments to identify key variables contributing to greenhouse gas emissions. This analysis also considers regional variations and the effectiveness of different production strategies in mitigating environmental impacts. This review indicates that wine typology (red or white) and grape variety are less significant in determining the carbon footprint than the production strategies employed. It identifies specific variables that contribute substantially to greenhouse gas emissions in wine production. The analysis highlights the need for standardized assessment methods to ensure accurate determination of influential factors in reducing emissions. This study concludes that achieving environmental sustainability in the wine industry requires a balanced approach that integrates environmental, economic, and social aspects. It emphasizes the necessity of developing standardized and universal strategies for assessing wine sustainability. The application of artificial intelligence is proposed as a crucial tool for improving data gathering, trend analysis, and formulating customized sustainability strategies for different wine regions. Addressing the challenges of sustainability in the wine industry is imperative for environmental preservation and the wellbeing of future generations.

Aromatic Characterisation of Moscato Giallo by GC-MS/MS and Validation of Stable Isotopic Ratio Analysis of the Major Volatile Compounds.

Among the Moscato grapes, Moscato Giallo is a winegrape variety characterised by a high content of free and glycosylated monoterpenoids, which gives wines very intense notes of ripe fruit and flowers. The aromatic bouquet of Moscato Giallo is strongly influenced by the high concentration of linalool, geraniol, linalool oxides, limonene, α-terpineol, citronellol, hotrienol, diendiols, trans/cis-8-hydroxy linalool, geranic acid and myrcene, that give citrus, rose, and peach notes. Except for quali-quantitative analysis, no investigations regarding the isotopic values of the target volatile compounds in grapes and wines are documented in the literature. Nevertheless, the analysis of the stable isotope ratio represents a modern and powerful tool used by the laboratories responsible for official consumer protection, for food quality and genuineness assessment. To this aim, the aromatic compounds extracted from grapes and wine were analysed both by GC-MS/MS, to define the aroma profiles, and by GC-C/Py-IRMS, for a preliminary isotope compound-specific investigation. Seventeen samples of Moscato Giallo grapes were collected during the harvest season in 2021 from two Italian regions renowned for the cultivation of this aromatic variety, Trentino Alto Adige and Veneto, and the corresponding wines were produced at micro-winery scale. The GC-MS/MS analysis confirmed the presence of the typical terpenoids both in glycosylated and free forms, responsible for the characteristic aroma of the Moscato Giallo variety, while the compound-specific isotope ratio analysis allowed us to determine the carbon (δ13C) and hydrogen (δ2H) isotopic signatures of the major volatile compounds for the first time.

Authenticity Markers of Aged Red Wines from Aglianico, Uva di Troia, Negroamaro and Primitivo Grapes.

The wide ampelographic treasure of Italian wine grape varieties is driving research towards suitable approaches for the varietal authenticity control of wine. In this paper, Aglianico, Negroamaro, Primitivo and Uva di Troia red wines, which were produced experimentally by single-grape winemaking from non-aromatic grapes native to southern Italy, were analyzed with respect to berry markers, namely anthocyanins, hydroxycinnamic acids (HPLC-DAD), shikimic acid (HPLC-UV) and glycosidic aroma precursors (GC-MS). The study confirms that, just as for the berries, useful varietal authenticity markers for red wine, even after aging, turn out to be hydroxycinnamic acids, relative amounts of acylated forms of anthocyanins, and shikimic acid, together with some grape glycosidic precursors from terpenes and C13- norisoprenoids. Principal Component Analysis was used as a valuable tool to highlight the results.

Chemical and sensory profile of nonconventional white wines from two different grape clones

AbstractThe present study aimed to characterize chemical and sensorial composition of Goethe wines from Goethe Grape's Valley Geographical Indication, Brazil. The wine samples were made from Goethe Clássica grape and its spontaneous clone, Goethe Primo, grown in two different micro‐regions located in the GI territory (2022 and 2023 vintages). Samples were produced by microvinification process and evaluated for classic oenological parameters, antioxidant activity, total polyphenol, organic acids, and sensory descriptive analysis. The results demonstrated that Goethe Clássica wines presented highest browning index, total acidity, antioxidant activity, and total phenolic content in both consecutive vintages. Moreover, in both vintages, the major organic acid in all Goethe wines was malic acid. The wine sensory analysis allowed the accomplishment of the sensorial attributes and its intensities previously unknown in the literature. The overall data afford new insights related to the impact of grape's genetic differences on wine sensorial and chemical characteristics.Practical ApplicationsThis research supports evidence for the relationship between chemical and sensory properties of wine and the sensorial differences in wines due to grape clonal variation. Moreover, the present study detailed the chemical and sensory profiles of wines derived from two different Goethe grape clones, a variety considered nonconventional for winemakers. Overall, the results of this research might be beneficial not only for the producers who are exploring novel or less prevalent wine grape varieties but also to the beverage industry more comprehension through genetic differences influencing wine quality and sensory perceptions.

Genetic Potential of Grapevine in Türkiye

Grape cultivation and viticulture, have been practiced since ancient times and make grape one of the oldest cultivated fruit species in the world, holding an important place in the social and economic structure of Eastern and Western civilizations in every period. It was determined as a result of archaeological excavations that the origin of Anatolian viticulture dates back to 3500 B.C. Two of the eight gene centers determined by Vavilov in the distribution of plant gene centers around the world (Near East and Mediterranean) intersect on the territory of Türkiye. Our country has a very rich vine genetic potential, both for wild vine (Vitis vinifera ssp. sylvestris) and cultivated vine (V. vinifera ssp. sativa), which means that Türkiye is the homeland of grapes. Due to its geographical location, Türkiye has ecological conditions that can be considered ideal for the cultivation of table and wine grape varieties. On the basis of research in the field of viticulture, the protection of existing genetic resources and ensuring sustainability should be prioritized. Plant genetic resources are strategic resources for sustainable plant production and are critical to maintaining food security today and in the future. Studies have been carried out by many researchers from the past to the present regarding the identification of grapevine genetic resources available in our country. Studies on determining our grapevine genetic resources started with ampelographic studies and continued with the use of biochemical markers, and today they are continued with the use of DNA markers. In this review, our grapevine genetic resources and their importance are described.

MultiFuseYOLO: Redefining Wine Grape Variety Recognition through Multisource Information Fusion.

Based on the current research on the wine grape variety recognition task, it has been found that traditional deep learning models relying only on a single feature (e.g., fruit or leaf) for classification can face great challenges, especially when there is a high degree of similarity between varieties. In order to effectively distinguish these similar varieties, this study proposes a multisource information fusion method, which is centered on the SynthDiscrim algorithm, aiming to achieve a more comprehensive and accurate wine grape variety recognition. First, this study optimizes and improves the YOLOV7 model and proposes a novel target detection and recognition model called WineYOLO-RAFusion, which significantly improves the fruit localization precision and recognition compared with YOLOV5, YOLOX, and YOLOV7, which are traditional deep learning models. Secondly, building upon the WineYOLO-RAFusion model, this study incorporated the method of multisource information fusion into the model, ultimately forming the MultiFuseYOLO model. Experiments demonstrated that MultiFuseYOLO significantly outperformed other commonly used models in terms of precision, recall, and F1 score, reaching 0.854, 0.815, and 0.833, respectively. Moreover, the method improved the precision of the hard to distinguish Chardonnay and Sauvignon Blanc varieties, which increased the precision from 0.512 to 0.813 for Chardonnay and from 0.533 to 0.775 for Sauvignon Blanc. In conclusion, the MultiFuseYOLO model offers a reliable and comprehensive solution to the task of wine grape variety identification, especially in terms of distinguishing visually similar varieties and realizing high-precision identifications.

A variety-specific analysis of climate change effects on California winegrapes

California contains a broad geography over which climate conditions can be suitable for cultivating multiple varieties of winegrapes. However, climate change is projected to make winegrape cultivation more challenging across many of California’s winegrowing regions. In order to understand the potential effects of climate change on winegrapes, this study models variety-specific phenology for six winegrape varieties and quantifies the change in phenology and viticulturally-important agroclimate metrics over 12 of California’s American Viticultural Areas (AVAs) by the mid-21st century. Results show more rapid development for winegrapes with earlier budburst, flowering, veraison, and maturation across all varieties and AVAs. Cabernet Sauvignon shows the greatest change in phenology timing, while Chardonnay shows the least change. Likewise, the West Sonoma Coast AVA shows the greatest average change in phenology timing across varieties and development stages and Lodi AVA shows the least. Projected changes in agroclimatic metrics include an additional month of potentially damaging heat days (above 35 °C) in some AVAs, and decreases in frost days. These results have implications for numerous factors related to viticultural production, including water resources management and crop yield and quality, and underscore the need for California winegrape growers to improve their resilience to climate change by adopting strategies such as increasing soil health and water use efficiency and selecting cultivars suited for future climate conditions. By conducting climate effects analyses at the variety-specific and AVA scale, important information is provided to the winegrowing industry at a resolution that can support decision-making towards resilience.

Genome editing of a recalcitrant wine grape genotype by lipofectamine-mediated delivery of CRISPR/Cas9 ribonucleoproteins to protoplasts.

The main bottleneck in the application of biotechnological breeding methods to woody species is due to the in vitro regeneration recalcitrance shown by several genotypes. On the other side, woody species, especially grapevine (Vitis vinifera L.), use most of the pesticides and other expensive inputs in agriculture, making the development of efficient approaches of genetic improvement absolutely urgent. Genome editing is an extremely promising technique particularly for wine grape genotypes, as it allows to modify the desired gene in a single step, preserving all the quality traits selected and appreciated in elite varieties. A genome editing and regeneration protocol for the production of transgene-free grapevine plants, exploiting the lipofectamine-mediated direct delivery of CRISPR-Cas9 ribonucleoproteins (RNPs) to target the phytoene desaturase gene, is reported. We focused on Nebbiolo (V. vinifera), an extremely in vitro recalcitrant wine genotypeused to produce outstanding wines, such as Barolo and Barbaresco. The use of the PEG-mediated editing method available in literature and employed for highly embryogenic grapevine genotypes did not allow the proper embryo development in the recalcitrant Nebbiolo. Lipofectamines, on the contrary, did not have a negative impact on protoplast viability and plant regeneration, leading to the obtainment of fully developed edited plants after about 5 months from the transfection. Our work represents one of the first examples of lipofectamine use for delivering editing reagents in plant protoplasts. The important result achieved for the wine grape genotype breeding could be extended to other important wine grape varieties and recalcitrant woody species.

ЭНОКАРПОЛОГИЧЕСКОЕ ИССЛЕДОВАНИЕ ГРОЗДЕЙ И ЯГОД НЕКОТОРЫХ АБОРИГЕННЫХ И ИНТРОДУЦИРОВАННЫХ СТОЛОВЫХ И ТЕХНИЧЕСКИХ СОРТОВ ВИНОГРАДА, ВЫРАЩИВАЕМЫХ В УСЛОВИЯХ АБШЕРОНА

The article presents the results of studying the enocarpological characteristics of bunches and berries of local and introduced table and wine grape varieties cultivated in the Absheron region. In the course of the studies, it was found that indicators such as bunch weight, stem weight, skin and pulp residue, juice yield, and the amount of solid residue varied over a wide range depending on the grape variety; in particular, large, medium and small bunches were observed. During the research, it was found that such table and technical grape varieties as Tuya-tish, wild form 2, Alphonse Lavallee, Nagshebi, Digah kechimemesi, Gyozel uzum, Ganjavi, Digah gorasy, Ag Kharji, Uzun salkhym, according to enocarpological indicators (bunch weight, stem weight, skin and pulp residue, juice yield, percentage of seeds in the berry, weight of 100 seeds, solid residue) were noticeably different from other varieties. In the studied table grape varieties, the enocarpological parameters varied over wide ranges, the average weight of the bunch was 210.0-974.0 g, the weight of the stem concerning the total weight of the bunch was 0.7-9.6%, the residue of the skin and pulp was 18.0-40.0 %, juice yield – 51.0-72.7 %, seeds – 2.4-10.8 %, amount of solid residue – 27.3-49 %, and weight of 100 seeds – 2.7-14.0 g. In wine grape varieties, these indicators differed from table varieties. They were estimated as follows: bunch weight 178.7-548.0 g, stem weight concerning the total weight of the bunch – 1.8-6.5 %, the skin and pulp residue – 14.7-31.6 %, juice yield – 64.1-76.2 %, seeds – 2.7-7.4 %, amount of solid residue – 23.8-43.0 %. The highest weight of the bunch, stem, remaining skin and pulp, number of seeds, weight of 100 seeds, and the lowest juice yield were noted in table varieties; for wine grape varieties, this ratio was the opposite. Key words: GRAPE VARIETIES, LOCAL VARIETIES, ENOCARPOLOGICAL INDICATORS, BUNCH, BERRIES

Effect of indoor dehydration on the chemical composition of Marselan grapes in Heyang of China.

Marselan is a red wine grape variety with great brewing prospects. The aim of this study was to investigate the effect of postharvest indoor dehydration on the quality of Marselan grapes. For two consecutive years, the harvested grapes were dehydrated naturally indoors (24-28°C). Fresh grapes were used as a control, and dehydrated samples were taken every 7 days during the period of dehydration until ending at day 28. Dehydration treatment increased degrees Brix, reducing sugars, glycerol, and malic acid. On day 7, there was an increase in protocatechuic acid, p-coumaric acid, and total tannin of 26.00%-27.73%, 11.43%-52.52%, and 39.74%-70.45%, respectively. With increasing dehydration time, total phenols, total flavonoids and total flavanols in the skins were decreased by 17.05%-38.13%, 24.32%-57.38%, and 17.05%-59.48%, respectively, with an increase in pH, citric acid, and ascorbic acid contents of grape juice by 7.66%-21.43%, 100%-137.50%, and 61.29%-258.82%, respectively. On day 21, the esters were increased by 1.10-1.75 factors. Partial least square-discriminant analysis result of volatile compounds showed that ethyl acetate, 1-propanol, 1-propanol, 2-methyl-, 1-hexanol, and 1-butanol, 3-methyl- were the predominant characteristic flavor compounds during dehydration of Marselan grapes. The effect of indoor dehydration on Marselan grape quality offered application value for China's later dehydration wine production.

Site-Directed Mutagenesis of VvCYP76F14 (Cytochrome P450) Unveils Its Potential for Selection in Wine Grape Varieties Linked to the Development of Wine Bouquet.

Bouquet is a fascinating wine characteristic that serves as an indicator of wine quality, developing during the aging process. The multifunctional monoterpenol oxidase VvCYP76F14 in wine grapes sequentially catalyzes three reactions to produce (E)-8-carboxylinalool, a crucial precursor for wine bouquet. Previous studies indicated that the activity of VvCYP76F14 derived from different wine grape varieties did not correlate with the amino acid sequence differences. In this study, 54 wine grape varieties were categorized into neutral, aromatic, and full-bodied types based on the sequence differences of VvCYP76F14, closely correlated with the content of wine lactone precursors. Computer modeling and molecular docking analysis of the full-bodied CYP76F14 revealed 17, 19, and 18 amino acid residues in the VvCYP76F14-linalool, VvCYP76F14-(E)-8-hydroxylinalool, and VvCYP76F14-(E)-8-oxolinalool complexes, respectively. Site-directed mutagenesis and in vitro enzyme activity analysis confirmed the substitutions of the key amino acid residues in neutral and aromatic varieties. Notably, the D299 mutation of VvCYP76F14 resulted in the complete loss of (E)-8-oxolinalool and (E)-8-carboxylinalool activities, aligning with the undetectable levels of (E)-8-oxolinalool and (E)-8-carboxylinalool in "Yantai 2-3-37", which harbors the D299T substitution. Favorably, VvCYP76F14 could serve as a cost-effective fingerprint marker for screening superior hybrid offspring with the desired levels of wine lactone precursors.

Pilot Scale Continuous Pulsed Electric Fields Treatments for Vinification and Stabilization of Arinto and Moscatel Graúdo (Vitis vinifera L.) White Grape Varieties: Effects on Sensory and Physico-Chemical Quality of Wines

Pulsed electric field (PEF) processing of white grapes (Arinto, Moscatel Graúdo also known as Moscatel de Setúbal) before pressing for must extraction (1.2 and 1.6 kV/cm) and before bottling for finished wine physical stabilization (10 kV/cm) was implemented in a pilot-scale winery to produce about 540 L of wine for each variety. PEF was applied at these two different stages of wine production, and its effects on the sensory and physico-chemical quality of the wines were investigated. The sensory triangle tests revealed no significant change in both wine varieties’ colour, odour, and taste with PEF extraction and PEF stabilization treatments. However, for colour coordinates assessed with a spectrophotometer, a significant increase in CIE b* colour coordinate was registered for PEF-extracted Arinto and Moscatel wine samples, showing a development of a more intense yellow colour. Concerning physico-chemical quality parameters, the PEF extraction increased both wine varieties’ turbidity and pH, although total acidity was not affected. The total phenols also increased in Arinto with extraction. The second PEF treatment applied for wine stabilization did not affect any of the quality parameters, except total phenols, which decreased in Moscatel wine. The results encourage the application of PEF in the wineries at different stages of vinification of white wine grape varieties.

Periodic Determination of Physical and Physiological Responses to High Temperature Stress in cv. Narince Grapes

Stress is a condition that affects or even inhibits growth, development and metabolism in plants. The type of stress, duration of application and severity also affect plants significantly. In this study, the weekly responses of Narince, a wine grape variety, to high temperature stress (HTS) in in vitro conditions were followed and stress was applied in two different periods, for 12 and 18 hours at 40°C. Some growth development (viability, fresh shoot weight, dry shoot weight, number of leaves, shoot length), physiological (ion flow and relative water content (RWC)) and biochemical (malondialdehyde (MDA)) analyses were done, with weekly follow-ups after the applications. In addition, the damage was graded visually. At the end of the application of both stresses, the percentage viability rate started to decrease. This rate decreased more slowly during HTS for 12 hours, while a faster decrease was observed in HTS for 18 hours. The number of healthy plants to be evaluated could not be reached after the fourth week. Growth and development parameters – fresh shoot weight (g), dry shoot weight (g) and shoot length (mm) – decreased after both stress applications, and these values were found to be statistically significant. After 12 hours of HTS application, the highest MDA value was determined at 0.274 nmol in the sixth week, while the lowest MDA value was determined in the first week, at 0.137 nmol. After 18 hours of HTS application, the highest MDA value was determined in the fourth week, at 0.263 nmol, while the lowest MDA value of 0.103 nmol was determined in the first week.

Influence of filtration treatments on grapevine DNA traceability in wine

Wine authentication through grapevine DNA traceability could be affected by wine technological processing treatments. In this study, filtration treatments including depth filter treatment using kieselguhr, perlite and membrane filtration using different types and pore sizes (0.22 and 0.45 μm) were applied on ‘Nebbiolo’ wine at an experimental scale. We used ‘Nebbiolo’ because it is an important Italian winegrape variety used to produce high-quality wines. Phenolic composition and color properties of the treated wines were examined using spectrophotometric and HPLC methods, while grapevine DNA traceability was evaluated using PCR based assays. The filtration treatments, as expected, significantly decreased turbidity compared to the unfiltered control, although total phenolics, total flavonoids and total non-flavonoids were not significantly affected. A significant reduction of acetylated anthocyanins by 6.1%–43.3% was observed in filtered wines, which could account for the reduced in total anthocyanins and color intensity of these wines. Grapevine DNA was significantly reduced in filtered wine by 37.2%–99.7%, with the reduction rate depending mainly on the properties of filter material. Polyvinylidene difluoride (PVDF) membranes with a pore size of 0.22 μm showed highest reduction of grapevine DNA in wine, resulting in the failure of TaqMan® single nucleotide polymorphisms (SNPs)-based assays used to detect grape DNA in wines.