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This study is an investigation of the impact of volatile phenols (VPs) released from burning wood during wildfires on grape composition and the resulting wines. Baseline levels of VPs in grapes and sensory differences between smoke-impacted wines and non-smoke-impacted wines were determined. The differences were related to different levels of smoke taint marker compounds in different wine matrices, using modified descriptive analysis (DA), multivariate statistics, gas chromatography mass spectrometry (GC-MS) and liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ-MS) of the free and total VPs, and individual bound glycosides, respectively. Across two DA panels, Cabernet Sauvignon, Cabernet Franc, Petite Verdot, Merlot, Syrah, Malbec, and Zinfandel wines made from grape originating from different areas in California were evaluated. The results show sensory differences between highly smoke-impacted and non-impacted wines with wines made from highly smoke-impacted grapes characterized as smoky, barbeque, medicinal, and having a retro-nasal ashtray character. Low smoke-impact wines based on free and total VP concentrations were not significantly different from the non-impacted wines when rated through descriptive analysis. The amount of smoke exposure was the largest contributor to smoke impact determined by sensory evaluation, but the different wine matrices from different locations and varietals also played an important role in determining the level of perceived smoke impact. The results of this study will contribute to our understanding of smoke impact and how it influences wine characteristics by relating smoke marker indicator compounds to wine sensory attributes. [ABSTRACT FROM AUTHOR]

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]

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]

Background: In Sicilian calcareous soils, red wines often display unripeness and bitterness features. To enhance wine quality, we employed the 'sur lies élevage' technique, involving prolonged contact of dead yeast cells with the wine to favor the extraction of yeast cellular components through cell lysis. The 7 month treatment utilized two types of Chardonnay lies: fresh and previously matured. To overcome challenges in retrieving lies from red winemaking, we have recovered the lies from a white winemaking. Additionally, the lies underwent a preliminary passage on a red wine to minimize color adsorption on yeast cell walls. Results: The sur lies treatment effectively reduced astringency, bitterness, and brown pigment in wines, with partial removal of red color. It successfully eliminated quercetin aglycone and induced remarkable changes in the aromatic profile, showing increased ethyl esters and relative fatty acids. Sensory evaluations revealed sur lies‐treated wines had fruitier and more complex characteristics compared to untreated wines. Matured lies had a greater impact on enhancing fruitiness than fresh lies. Conclusions: The treatments mitigated the unripeness and bitterness of studied wines. Sur lies treatment improved the aromatic profile, leading to fruitier and more complex notes, enhancing overall sensory quality. Matured lies showed greater efficacy in elevating fruitiness than fresh lies. These findings highlight the value of the sur lies technique in enhancing the quality and sensory attributes of Nero d'Avola and Syrah wines from Sicilian calcareous soils. © 2023 Society of Chemical Industry. [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]

A comparative technological study of wines from four seedless coloured hybrid vine forms-30/2, 30/3, 30/10, 31/9 and the varieties-Syrah clone 174, Sangiovese, Marselan and Regent. It was found that on the content of trans-resveratrol, quercetin and antioxidant activity of wine, all studied hybrid forms are superior to Sangiovese and inferior to Syrah-clone 174. With a high degree of balance and stability of environmental conditions of the varieties are Syrah-clone 174, Marselan and Regent, and of the hybrid forms-30/10 and 30/2. Various representatives of the volatile aromatic composition have been identified in the studied wines, belonging to the groups of higher alcohols, esters and terpenes, acetaldehyde and methanol. The total quantitative presence of volatile compounds is higher in the wines of the hybrid forms compared to those of the control varieties. The content of sugars and acids in grapes, and alcohol and sugars in wine in hybrid forms and varieties does not differ significantly. The amounts of extract, titratable acids, anthocyanins are higher in hybrid forms. The highest amount of total phenols is observed in the wine of 30/10-3295.66 mg/dm³, and the lowest in Sangiovese-2060.91 mg/dm3 . With the highest organoleptic evaluation is the wine from Syrah clone 174-86.0, and from the seedless coloured hybrid forms are 30/10-83.0 and 30/3-80.0. It is possible through staged sexual hybridization to create seedless coloured varieties suitable for the production of quality wines, characterized by high taste characteristics, nutritional and medicinal value. [ABSTRACT FROM AUTHOR]

During the period 2020-2022, an experiment was conducted in the experimental vineyard of the Agricultural University - Plovdiv, and four clones of the wine variety Syrah, numbered 100, 174, 470 and 524, grafted on the SO4 rootstock were selected as the study object. During the "pea size" phase, the green pruning operation – bunch thinning was applied. The shoots growth starts from the vegetation phase "first leaf appearance" and ends at the "veraison". The average duration is about 100 days, covering the period of May, June and July. It was found that the vine shoots from a clone 470 reached the greatest average length, V3 - 285, 265, 290 cm and V7 - 359, 336, and 380 cm, and those from a clone 100 were distinguished by the weakest growth, V1 - 197, 203 and 205 cm and V5 - 240, 228 and 245 cm. Differences were proven between the variants, both in the non-reduced (V1, V2, V3, and V4) and in those with reduced yields (V5, V6, V7, and V8), as after reducing the number of bunches, the length of the shoots was longer - high in all vines from the used Syrah clones. This study provides information on the relationship between the applied green pruning operation (bunch thinning) during the growing season and its effects on the vegetative growth. Balancing the vines bud load by controlling yield during the growing season is a preferred viticultural practice for increasing the grape quality. [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]

Wine flavour is a critical driver of customer impression of quality associated with liking the wine and tendency to repurchase. However, winemaker and expert assessments poorly reflect customer impressions of wine flavour, and currently, available predictive capabilities are limited. This study developed predictive models for customer perceptions of Shiraz wine flavour, utilising the proportion of customer wine reviews mentioning a descriptor as the indicative measure to be predicted. To achieve this, two strategies were explored, which involved polynomial regression sourcing input terms from either: (1) volatile profiles directly, or (2) odour intensity (OI) values, produced via transformation of the volatile profiles using modified vector modelling (MVM). Neither strategy significantly outperformed the other (P = 0.834), however across the two strategies, a subset of 18 models from the 169 models generated had very good predictive potential (10-fold R² > 90%). The 18 models presented herein provide a novel capacity for winemakers to predict customer perceptions of their Shiraz wine prior to market launch, to guide a marketing strategy to maximise customer satisfaction and thereby product success. [ABSTRACT FROM AUTHOR]

Background and Aims. Vineyard performance is impacted by water availability including the amount and seasonality of rainfall, evapotranspiration, and irrigation volume. We benchmarked water-limited yield potential (Yw), calculated yield gaps as the difference between Yw and actual yield, and explored the underlying environmental and management causes of these gaps. Methods and Results. The yield and its components in two sections of 24 Shiraz vineyards were monitored during three vintages in the Barossa zone (GI). The frequency distribution of yield was L-shaped, with half the vineyards below 5.2 t·ha−1, and an extended tail of the distribution that reached 24.9 t·ha−1. The seasonal ratio of actual crop evapotranspiration and reference evapotranspiration was below 0.48 in 85% of cases, with a maximum of 0.65, highlighting a substantial water deficit in these vineyards. A boundary function relating actual yield and seasonal rainfall was fitted to quantify Yw. Yield gaps increased with an increasing vine water deficit, as quantified by the carbon isotope composition of the fruit. The yield gap was smaller with higher rainfall before budburst, putatively favouring early-season vegetative growth and allocation to reproduction, and with higher rainfall between flowering and veraison, putatively favouring fruit set and berry growth. The gap was larger with higher rainfall and lower radiation between budburst and flowering. The yield gap increased linearly with vine age between 6 and 33 yr at a rate of 0.3 t·ha−1·yr−1. The correlation between yield gap and yield components ranked bunch weight ≈ berries per bunch > bunch number > berry weight; the minimum to close the yield gap was 185,000 bunches ha−1, 105 g bunch−1, 108 berries bunch−1, and 1.1 g berry−1. Conclusions. Water deficit and vine age were major causes of yield gaps. Irrigation during winter and spring provides an opportunity to improve productivity. The cost of dealing with older, less productive vines needs to be weighed against the rate of increase in yield gap with vine age. Significance of the Study. A boundary function to estimate water-limited yield potential returned viticulturally meaningful yield gaps and highlighted potential targets to improve vineyard productivity. [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 is a product obtained through fermentation process, the trans-resveratrol is a polyphenol derived from grapes and a natural antioxidant that passes into wine. The trans-resveratrol is a rare compound with the highest content in the red wine and a positive physiological effect on human organism. The present study was conducted in three years period from 2020 until 2022 at the Agricultural university-Plovdiv experimental vineyard, located near the village of Brestnik. Four Syrah wine variety clones were included and eight experimental wines have been made during the experimental period. In all tested wines, the presence of trans-resveratrol was detected but its amount was higher in clone 524 (V4) with non-reduced yield (3.35, 4.36, 7.02 mg/L), and in clone 100 (V5) with reduced yield (5.24, 3.75, 7.23 mg/L). Reducing the bunch numbers at the “pea size” stage did not significantly influence the content of trans-resveratrol. The wine antioxidant properties were directly affected by the clone and the grape harvest and was under the terroir influence. In today's conditions of overproduction and increased competition, the results of this study provide a valuable economic information and expand the portfolio of wineries. [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]

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]

Color is a major quality trait of rosé wines due to their packaging in clear glass bottles. This color is due to the presence of phenolic pigments extracted from grapes to wines and products of reactions taking place during the wine-making process. This study focuses on changes occurring during the alcoholic fermentation of Syrah, Grenache and Cinsault musts, which were conducted at laboratory (250 mL) and pilot (100 L) scales. The color and phenolic composition of the musts and wines were analyzed using UV-visible spectrophotometry, and metabolomics fingerprints were acquired by ultra-high performance liquid chromatography−high-resolution mass spectrometry. Untargeted metabolomics data highlighted markers of fermentation stage (must or wine) and markers related to the grape variety (e.g., anthocyanins in Syrah, hydroxycinnamates and tryptophan derivatives in Grenache, norisoprenoids released during fermentation in Cinsault). Cinsault wines contained higher molecular weight compounds possibly resulting from the oxidation of phenolics, which may contribute to their high absorbance values. [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]

Flavour scalping in wine is a well-known phenomenon that is defined as the sorption of flavour compounds on wine closures. While the impact of closure type was the object of several studies, no research has addressed the impact of wine closure permeability on flavour scalping. For that purpose, the adsorption of volatile sulphur compounds (VSCs) on four micro-agglomerated wine cork closures was investigated by soaking them in model and Shiraz wines for 7 days. From a kinetic point of view, most of the VSCs were quickly scalped after 1 h of soaking, and this effect increased after 6 h until reaching a plateau. Most importantly, no significant impact of the closure on the kinetics and adsorption rates of the VSCs was found. As to the quantitative aspects, VSC sorption on closures accounted for 1% to 5% of the initial VSCs present in the wines only, meaning that the impact was negligible under oenological conditions. [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]

Grenache wines from the Central Coast of California were subjected to different alcoholic fermentation temperature regimes (Cold, Cold/Hot, Hot) and cap management protocols, namely, punch down (PD), or no punch down (No PD), to determine the effect of these practices on the color, aroma, and the retronasal and mouthfeel sensory characteristics of the resulting wines. Descriptive analysis (n = 8, line scale rating 0–15) results indicated that the combination of a hot fermentation temperature and no punch downs led to a significantly higher intensity in perceived color saturation (7.89) and purple hue (8.62). A two-way analysis of variance (ANOVA) showed that cap management was significantly more impactful on the perception of orthonasal aromas than fermentation temperature. The reduction aroma was significantly higher in No PD wines (5.02) compared to PD wines (3.50), while rose and hot aromas had significantly higher intensity perception for PD wines (5.18, 6.80) than for No PD wines (6.80, 6.14). Conversely, analysis of selected volatile compounds indicated that fermentation temperature was more impactful than cap management regime. Cold/Hot wines had higher concentrations of important esters such as ethyl hexanoate (650 µg/L) and isoamyl acetate (992 µg/L). Cold wines had a higher concentration of β-damascenone (0.719 µg/L). TCATA evaluation (n = 8) indicated that Cold/Hot PD wines had a significantly higher citation proportion of fruit flavor (1.0) and velvet astringency perception (0.80) without significant reduction flavors. Finally, the present study represents a contribution with the main volatile compounds (e.g., β-damascenone and esters in the Cold and Cold/Hot fermented wines, respectively; hexanol in PD wines, which may be potentially responsible for a hot mouthfeel), and sensory characteristics (red fruit, tropical fruit, white pepper, and rose) of Grenache wines grown in the Mediterranean climate of the Central Coast of California. [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]

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]

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]

Background and Objectives: Staphylococcus aureus is responsible for the majority of food poisoning all around the world. Nasal carriers of S. aureus and foodstuffs need for handling are important sources and vehicles to transmit this pathogen to ready-to-eat foods. According to hygienic standards, confectioners should not be contaminated with S. aureus. This study aimed to detect nasal carriers and creamy pastries contaminated with enterotoxigenic S. aureus in confectioneries of Shiraz, Iran. Materials and Methods: From the confectioneries of Shiraz city, 27 places in the north, south, center, west, and east areas were selected randomly then 100 creamy pastries samples and 117 nasal swabs were collected. Bacteriological and biochemical tests were performed to isolate S. aureus. The polymerase chain reaction (PCR) test was used to identify the virulence and enterotoxins genes of the S. aureus isolates. Agar disk diffusion was performed to find out the antibiotic resistance of the isolates. Results: Results revealed that 16.24 and 33 percent of workers and creamy pastries were contaminated with S. aureus respectively. Also, 100%, 37%, 58%, and 6% of nasal samples harbored femA, mecA, sea, and sec genes respectively. According to the results 97%, 70%, 54.5%, and 6% of creamy pastries isolates harbored femA, mecA, sea, and sec genes respectively. No isolate carried seb and sed genes. The results also showed that 41.5% of nasals and 5.5% of creamy pastry isolates harbored both sea and sec genes. The sea was the most common enterotoxin gene observed in nasal and creamy pastries. The results of the antimicrobial resistance test showed that 68.42% of nasal and 48.48% of creamy pastry isolates were resistant to cefocxitn (FOX) respectively. Both nasal (89%) and creamy pastry (82%) isolates presented the highest resistance to penicillin (P) and the most sensitivity to trimethoprim-sulphamethoxazole (SXT) (94%). Most of the isolates were sensitive to erythromycin (E), aztreonam (AZM), tetracycline (TE), trimethoprim (TMP), and ciprofloxacin (CP). Isolates of S. aureus harboring multi-enterotoxin genes were resistant to more antibiotics than others. Conclusion: The presence of enterotoxigenic S. aureus in the workers' nasal samples and creamy pastries of Shiraz confectioneries was high which is a potential public health hazard. [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]

BACKGROUND: Proanthocyanidins (PAs) are phenolic compounds present in skins and seeds of wine grapes and have great implications for plant physiology and wine quality. There are several strategies to increase PA concentration, such as application of elicitors methyl jasmonate (MeJ) and benzothiadiazole (BTH), compounds that can stimulate defence responses like phenolic compound biosynthesis in wine grapes, which have been applied mainly at veraison (beginning of ripening). We recently evaluated the application of MeJ and BTH on Vitis vinifera cv. Monastrell grapes during veraison and mid‐ripening (3 weeks after veraison). Grapes treated at mid‐ripening showed higher anthocyanin concentrations than those at veraison. In this trial, over two seasons, we evaluated whether time of application (veraison or mid‐ripening) of MeJ and BTH on 'Monastrell' grapes is a determining factor in the biosynthesis and composition of PAs in grapes and their subsequent release into wines. RESULTS: Application of elicitors at different ripening times produced significant differences in the PAs of 'Monastrell' grapes, since those treated at mid‐ripening recorded a higher PAs concentration in skin and seeds, and then in the wines produced, compared to grapes treated at veraison. CONCLUSION: Results suggest that despite different environmental conditions endured in each of the two seasons evaluated, application of elicitors at mid‐ripening of Monastrell grapes could be used to harvest grapes with higher PA concentration, increasing the functional value of the wines, without altering their organoleptic quality. © 2022 Society of Chemical Industry. [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]

Dyslipidemia is considered a risk factor for the development of insulin resistance and cardiovascular diseases, such as left ventricular hypertrophy and remodeling of the arterial wall. Resveratrol, present in grapes, has been studied as a possible mediator of cardiovascular protection. The present study aimed to evaluate the effect of red wine from the Merlot grape (Vitis vinifera L.) on dyslipidemia and its involvement in male mice, knockout for the LDL receptor gene (LDLR-/-). The mice were divided into 4 experimental groups: Group S received standard rodent food; Group SV received standard feed for rodents and wine; Group HL received high fat diet; Group HLV received hyperlipidic food and wine orally for 60 days. All animals received water and food ad libitum during this period. After this period, they remained fasting and were then anesthetized. Blood was collected for serum analysis of triglycerides, total cholesterol, and its fractions (HDL and VLDL), C-reactive protein, glucose, and insulin to compare the data. Morphometric and histological analyzes of the left ventricle and abdominal aorta were also performed. It was found that Merlot red wine has antidyslipidemic effects on genetic dyslipidemia, associated with food, partially preventing insulin resistance, hyperinsulinemia and increased CRP; as well as cardiovascular effect, partially preventing LVH and arterial remodeling. [ABSTRACT FROM AUTHOR]

• Grape total anthocyanins decrease with increasing Tmin before veraison. • Grape extractable anthocyanins decrease with increasing Tmin and Tmax during ripening. • Increasing Tmin and Tmax during ripening decrease flavonols and total polyphenols. • Water availability decrease total anthocyanins but favour their extractability. • Flavonol content is not significantly affected by water availability. In view of the increase in temperature observed in recent years and its projection, there is a great concern about its effects on grape quality, especially in warm areas. This research aims to contribute to this knowledge by assessing the effect of temperature and water availability along the growing cycle on grape quality and in particular on the phenolic compounds and their extractability. The research was carried out in a commercial vineyard in La Mancha Designation of Origen (Spain) planted with Merlot. Edaphoclimatic characteristics and the grape composition at maturity were evaluated for several years in the period 2007–2017. An increase in temperature decreased the content of phenolic compounds, while higher water availability contributed to increase their levels in the grapes. Total anthocyanin content was mainly affected by minimum temperature before veraison while extractable anthocyanin, flavonols and total polyphenols were affected by both maximum and minimum temperature during ripening. Higher water availability decreased the concentration of anthocyanins but favoured their extractability, while flavonols were not significantly affected by water availability. Thus, phenolic ripening can be affected by changes in temperature and water distribution throughout the growing cycle, but due to the opposite sign of their effect they may be partially balanced. The projected warmer conditions can affect phenolic composition of Merlot and therefore quality of the wines made with such variety. In order to maintain grape quality, strategies to reduce heat stress should be adopted, and irrigation doses and timing should be adapted not only in the ripening period but also in the period prior to veraison. [ABSTRACT FROM AUTHOR]

Anthocyanins are phenolic compounds that provide colour to young red wines following extraction from grape skins, and their reaction kinetics are not well understood as they exist within a complex pH-dependent multistate system. For commercial wineries to best control anthocyanin colour expression that is a major determinant for red wine quality, there is a critical need for behaviours of all pH-dependent monomeric and self-associated anthocyanins to be considered together. In response, the current study employed mathematical and experimental techniques to reveal kinetic and steady-state behaviours of all species of a model anthocyanin, malvidin-3-O-β-D-glucopyranoside (M3G), within three Shiraz red wines throughout fermentation. Investigator-developed models represented the following: (i) acid–base reactions that form red, purple, and blue anthocyanin monomers; (ii) hydration reactions that result in monomeric colour loss; and (iii.) physical self-association interactions that temporally stabilise anthocyanin colour. Simulations were validated experimentally using high-performance liquid chromatography with diode array detector (HPLC–DAD) and colourimetric analysis of wine samples. Moreover, a unique predictive modelling framework was developed that takes in measured values for anthocyanin concentration, pH, and temperature at the onset of fermentation, and output data describing corresponding wine colour expression and stability characteristics that would arise after fermentation has progressed. Results of the current study elucidate complex reaction kinetics occurring between anthocyanin species under dynamic red wine conditions and provide meaningful predictions for future wine colour and shelf-life characteristics. Outputs may be used to inform key winemaking decisions influencing red wine quality and to optimise the use of winery resources throughout the fermentation process. [ABSTRACT FROM AUTHOR]

A spatial sampling design determines where sample locations are placed in a study area so that population parameters can be estimated with good precision. Spatially balanced designs draw samples with good spatial spread and provide precise results for commonly used estimators when surveying natural resources. In this article, we propose a new sampling strategy that incorporates ranking information from nearby locations into a spatially balanced sample. If the population exhibits spatial trends, our simple local ranking strategy can improve the precision of commonly used estimators. Numerical results on several test populations with different spatial structures show that local ranking can improve the performance of a spatially balanced design. To show that local ranking is simple and effective in practice, we provide an example application for the health and productivity assessment of a Shiraz vineyard in South Australia. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

It is widely recognized that wine aroma critically influences wine quality, yet the extent to which volatile compound composition in wine determines wine quality has proven difficult to define, beyond the negative influence of taint compounds. While some relationships between concentration of volatile aroma compounds and wine quality have been made, this has been usually based on single molecules, in laboratory wines and without reference to experienced wine panels. Here, we collected and analysed 157 commercial Shiraz wines from a competitive show over 2 years. We found significant (P <.05) correlations between specific volatiles and the panel's wine quality scores. However, these correlations were not always consistent between years. We could not explain medals given to wine entries solely based on multivariate analysis of their composite volatile composition. Here, we suggest that aroma determination in judging wine quality does not completely explain the assessment of wine, and appearance (colour, clarity) and taste may be more influential factors. There are considerable practical difficulties in establishing a convincing wine quality prediction model based on analysis of volatile compounds alone. [ABSTRACT FROM AUTHOR]

Excessive consumption of synthetic food dyes by children may raise concerns about their health. These dyes may aggravate the hyperactivity symptoms and exacerbate asthma in sensitive children. The purpose of this study was to determine the presence of sunset yellow and quinoline yellow dyes, as well as tartrazine in dairy‐free fruit ice cream, freeze pop, jelly, and candy. Additionally, we evaluated the amount of two food dyes consumed by children. To do so, a total of 150 food samples, including 20 dairy‐free fruit ice creams, 25 freeze pops, 57 jelly products, and 48 types of candy were randomly selected from stores in Shiraz, Iran. Then, using the high‐performance liquid chromatography (HPLC) method and an ultraviolet (UV) detector, we measured the amounts of sunset yellow and quinoline yellow dyes and identified the use of tartrazine. Also, the per capita consumption (grams per day) of the mentioned foods was calculated using a checklist in two groups of male and female primary schoolchildren aged 6–9 years and 10–13 years in Shiraz, Iran. According to the results, 11 (7.33%) samples contained only tartrazine and 107 (71.33%) samples contained quinoline yellow and sunset yellow synthetic dyes. In addition, of 107 samples that used quinoline yellow and sunset yellow, 102 (95.33%) contained unauthorized tartrazine. Only seven (6.54%) samples contained exceedingly high concentrations of authorized quinoline yellow and sunset yellow synthetic dyes. However, the exposure assessment showed that the intake of quinoline yellow and sunset yellow was at average levels and the 95th percentile in both age groups was less than the associated acceptable daily intake (ADI). For synthetic dyes, the target hazard quotient (THQ) and hazard index (HI) were less than one, indicating that ingestion of these two dyes via food products does not pose a risk to children's overall health. [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]

Vine undergoes seasonal changes repeated annually in a certain sequence. In the spring time, the shoots’ development and inflorescences begin, flowering occurs, and in the summer the berry size increases, after the grapes and shoots ripen. This period of active life is called the growing season. The main phenological stages duration: bud burst, first leaf appearance, first inflorescens appearance, flowering, bunch clossure and technological maturity (veraison) differ for each variety (clone). The length of the growing season for each variety is directly related to the vineyard location, air and soil temperature, soil moisture and management practices. This study aims to compare the main phenological stages and determine the differences between clones from the Syrah variety, regarding the influence of air temperature. [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]