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BACKGROUND: The influences of abscisic acid (ABA) applications on precursors and gene expression in 3‐alkyl‐2‐methoxypyrazines (MPs) biosynthetic pathway, MPs concentration and sensory evaluation of its derived peculiar odors in Cabernet Sauvignon grapes and wines were investigated. At the vineyard, ABA solution with 25, 100 and 400 mg L−1 (AT1, AT2 and AT3, respectively) and an aqueous solution (control) were sprayed three times from veraison to pre‐harvest. RESULTS: Higher concentration ABA applications (AT2 and AT3) in grapes could significantly reduce MPs concentration and its derived peculiar odors in grapes and wines compared to a lower concentration ABA application (AT1) and control, with AT2 application having the strongest effect. The changes in MPs were mainly a result of the downregulated expression of VvOMTs genes at higher concentration ABA applications, independent of the levels of their potential precursors. CONCLUSION: The present study reveals that ABA application had the potential to decrease production of MPs in Cabernet Sauvignon grapes and wines, and this result provides reference values for the removal of unpleasant vegetable odors from Cabernet Sauvignon wines in production. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Viticulture has adapted foliar applications of biostimulants as a tool to improve crop quality. Recently, nanotechnology has been incorporated as a strategy to reduce the loss of biostimulants and treat nutrient deficiencies. Therefore, the present study aimed to investigate the effect of foliar applications of amorphous calcium phosphate nanoparticles (ACP) doped with methyl jasmonate (ACP‐MeJA) and urea (ACP‐Ur), individually or together (ACP‐MeJA+Ur), on the content of volatile compounds in ‘Tempranillo’ grapes, compared to the conventional application of MeJA and Ur, individually or in combination (MeJA+Ur).The results showed that nanoparticle treatments reduced the total C6 compounds and some carbonyl compounds in the grape musts. This is of novel interest because their presence at high levels is undesirable to quality. In addition, some aroma‐positive compounds such as nerol, neral, geranyl acetone, β‐cyclocitral, β‐ionone, 2‐phenylethanal and 2‐phenylethanol increased, despite applying MeJA and Ur at a lower dose.Consequently, although few differences in grape volatile composition were detected, nanotechnology could be an option for improving the aromatic quality of grapes, at the same time as reducing the required doses of biostimulants and generating more sustainable agricultural practices. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Flavonoids are vital for the development of high‐quality grapes and wine, and manganese deficiency decreases grape berry coloration. However, the effects and underlying mechanisms of action of manganese sulfate on grape metabolic profiles have not been adequately researched. In this study, three concentrations of manganese sulfate solutions, 0.5 μmol·L−1 (low, L), 5 μmol·L−1 (middle, M – the standard manganese concentration of Hoagland nutrient solution, control), and 1000 μmol·L−1 (high, H), were applied to the 'Cabernet Sauvignon' grapevine (Vitis vinifera L.) to explore the effect on berry composition. RESULTS: Manganese application improved manganese concentration effectively in grape organs. Furthermore, the concentrations of malvidin 3‐O‐(6‐O‐acetyl)‐glucoside, malvidin 3‐O‐glucoside, malvidin‐trans‐3‐O‐(6‐O‐p‐coumaryl)‐glucoside, and peonidin 3‐O‐(6‐O‐acetyl)‐glucoside increased significantly under H treatment. Weighted gene co‐expression network analysis (WGCNA) revealed that the structural genes (VvDFR, VvUFGT, and VvOMT) of flavonoid biosynthesis were upregulated under H treatment, and their transcription levels correlated positively with malvidin‐ and peonidin‐derived anthocyanin concentrations. CONCLUSIONS: This study suggested that manganese application regulates berry transcriptional and flavonoid metabolic profiles, providing a theoretical basis for improving the color of red grapes and wines. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Grapevine red blotch virus (GRBV) is a recently discovered virus and a major concern for the wine industry. Prior research indicated that GRBV delays grape ripening by reducing °Brix and anthocyanin concentrations in grapes from infected vines, resulting in higher ethanol concentrations in wines made from healthy fruit compared to diseased vines, which have an impact on sensory properties. In this study, infected fruit (Vitis vinifera L. Merlot) was sequentially harvested (in 2016 and 2017) and chaptalized (in 2017) to ameliorate the impact of GRBV on grape and final wine composition. RESULTS: Chemical parameters including phenolic and volatile profiles of grapes and their subsequent wines were measured. Sensory properties were determined by descriptive analyses. Results demonstrated that GRBV decreased sugar accumulation and anthocyanin synthesis in grapes. Wines from GRBV grapes harvested at later ripening stage produced wines that were more similar chemically and sensorially to wines made from healthy fruit than to wines made from GRBV fruit harvested earlier. CONCLUSION: A longer hang time of GRBV grapes is a potential strategy to mitigate the impacts of GRBV. However, chaptalization of diseased fruit must was inefficient at increasing similarities to wines made from healthy fruit. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Melatonin is an endogenous free radical scavenger with antioxidant activity that preserves the commercial value of postharvest fruits and delays fruit senescence. To explore the effect of exogenous melatonin on antioxidants and aroma volatile compounds of grapes (Vitis labrusca × vinifera 'Kyoho'), the grapes were treated with distilled water (control), 50 μmol L−1 of melatonin (M50), and 100 μmol L−1 of melatonin (M100) for 30 min and were then stored at 4 °C for 25 days. RESULTS: Exogenous melatonin decreased the rachis browning index, the decay development, the weight loss rate, the berry abscission rate, and the respiration rate, promoted the accumulation of total phenolics and total flavonoids, and delayed the reduction of anthocyanins and total soluble solids. In volatile compounds, the accumulation of esters, aldehydes, and alcohols in grapes was promoted, and the terpenes content was reduced by exogenous melatonin. CONCLUSION: Exogenous melatonin had potentially positive effects on the postharvest life and quality maintenance of grapes. These findings provide theoretical support for the application of melatonin in grape storage and preservation. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Official stable isotope databases, based on the analysis of (D/H)I ethanol, (D/H)II ethanol, δ13Cethanol and δ18Owater of wine, are an indispensable tool for establishing the limits beyond which the mislabeling or the addition of sugar and/or water in wine production can be detected. The present study investigates, for the first time, whether the use of hybrid varieties instead of European Vitis vinifera for wine production can have an impact on the stable isotope ratios. RESULTS: The analyses were performed by isotope ratio mass spectrometry and site‐specific natural isotope fractionation by nuclear magnetic resonance, in accordance with the official methods of the International Organization of Grapes and Wine. The comparison shows the tendency of some stable isotope ratios of hybrid varieties, in particular (D/H)I, to deviate from the regional averages of the V. vinifera samples. Notably, Baron, Monarch and Regent showed significantly different values at one of the two sampling sites. Particularly high δ13C values characterize Helios compared to other hybrid varieties. CONCLUSION: For the first time, and from an isotopic point of view, the present study investigates the wine obtained from hybrid varieties, showing that further attention should be paid to their interpretation, on the basis of the database established according to the European Regulation 2018/273. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND The grape volatile fraction determines to a great extent its aroma, which is one of the most important characteristics influencing wine quality and consumer preferences. Grapevine downy mildew (GDM) is one of the most important and devastating diseases of grapevines worldwide. In this study, the impact on the volatile composition of cv. Verdicchio grapes of classical copper formulations, was compared to that of alternative products. Thus, 11 treatments were foliar applied throughout one grapevine cycle. RESULTS: Most of the volatile compounds present in the grapes were not affected by the treatments used in order to prevent GDM. In the case of the total C13 norisoprenoids, some differences were found between grapes untreated control and those applied with the grapefruit seed extract. Moreover, the content of alcohols was smaller in grapes from Bordeaux mixture treatment and higher in the samples from chitosan application. CONCLUSION: Therefore, from the qualitative point of view of the berry, treatment with tested products alternative to copper is recommended, which minimize the environmental and health problems that this heavy metal brings to the soil and in the winery, since it means that their applications did not affect the grape aroma. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND In monsoonal climates, grape anthocyanin and proanthocyanidin (PA) accumulations are unsatisfactory for producing optimal wine. Agronomical practices are often considered to be effective means for regulating fruit components. However, there is a lack of quantitative information on the effects of deficit irrigation (DI), basal leaf removal (LR) or their combination of deficit irrigation and leaf removal (DILR) on the characteristics of anthocyanin and PA compositions and their implications on the resulting wine quality. In this study, the dynamics of grape anthocyanin and PA accumulation were investigated in DI, LR and DILR during grape ripening, and the resulting wine profile was assessed. RESULTS: The contents of reducing sugar and total anthocyanins in Cabernet Sauvignon berries were significantly increased by DI, LR and DILR, while titratable acidity, total flavan‐3‐ols and tannins levels were generally decreased. Notably, the levels of 3′5′‐substituted anthocyanins, such as malvidin and its derivatives significantly increased, and 3′‐substituted anthocyanins decreased in both grape and wine under DI and DILR strategies. Skin PAs were sensitive to water deficits, whereas they were insensitive to LR. In resulting wine, PAs content and the proportion of 3′‐hydroxylated PAs, such as (+)‐catechin, (−)‐epicatechin and (−)‐epicatechin‐3‐O‐gallate units were significantly decreased under DI and DILR, while molecular mass and the proportion of 3′5′‐hydroxylated units of PAs were increased in response to DILR. CONCLUSION: The DILR was the most favorable for the repartitioning of anthocyanin and PA metabolites, and promoted the accumulation of tri‐substituted forms contributing a higher color intensity, mouthfeel persistence, structure, and astringency of wine. This information provides an important strategy for modulating the anthocyanin and PA compositions by agricultural practices and achieving the desired quality of grapes and wines in monsoonal climates. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND Although the grape berries are deliberated as a non‐climacteric fruit, ethylene seems to be involved in grape berry ripening. However, the precise role of ethylene in regulating the ripening of non‐climacteric fruits is poorly understood. RESULTS: Exogenous ethephon (ETH) can stimulate the concentration of internal ethylene and accelerate the accumulation of anthocyanins in berries of 'Fujiminori', including malvidin‐, delphinidin‐, and petunidin‐derivatives (3′,4′,5′‐trihydroxylated anthocyanins) and cyanidin‐derivatives (3′,4′‐dihydroxylated anthocyanins). The content of 3′,4′,5′‐trihydroxylated anthocyanins was extremely higher than 3′,4′‐dihydroxylated anthocyanins, and ethylene did not affect the composition of anthocyanins in grape. Furthermore, we observed the expression of anthocyanin structural and regulatory genes as well as ethylene biosynthesis and response genes in response to ETH treatment. The anthocyanins accumulation is significantly associated with increased expression of anthocyanin structural (VvPAL, Vv4CH, VvCHS, VvCHI, VvF3H, and VvUFGT) and regulatory genes (VvMYBA1, VvMYBA2, and VvMYBA3), which persisted over the 12 days. In addition, exogenous ETH affected the endogenous ethylene biosynthesis (VvACO2 and VvACO4) and the downstream ethylene regulatory network (VvERS1, VvETR2, VvCTR1, and VvERF005). CONCLUSIONS: These findings bring new insights into the physiological and molecular function of ethylene during berry development and ripening in grapes. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Filamentous fungi are the main contamination agent in the viticultural sector. Use of synthetic fungicides is the regular answer to these contaminations. Nevertheless, because of several problems associated with the use of synthetic compounds, the industry demands new and safer methods. In the present work, the biopreservation potential of four lactic acid bacteria (LAB) strains was studied against the principal grape contaminant fungi. RESULTS: Agar diffusion test evidenced that all four culture‐free supernatant (CFS) had antifungal properties against all tested fungi. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) test values evidenced that media fermented by the Lactobacillus plantarum E3 and Lactobacillus plantarum E4 strains showed the highest antifungal activity, resulting in an MFC from 6.3 to 100 g L−1. Analysis of CFS evidenced the presence of different antifungal compounds, such as lactic acid, phenyllactic acid and pyrazines. In tests on red grapes, an average reduction of 1.32 log10 of the spores per gram of fruit was achieved by all CFS in grapes inoculated with Aspergillus ochraceus and by 0.94 log10 for L. plantarum E3 CFS against Botrytis cinerea. CONCLUSION: The antifungal activity of the fermented CFS by L. plantarum E3 reduced the growth of B. cinerea and A. ochraceus in grapes, which are the main contaminant and main producer of ochratoxin A in these crops, respectively. Therefore, based on the results obtained in this work, use of the strain L. plantarum E3 could be an interesting option for the biopreservation of grapes. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND The importance of monoterpenes in grape and wine aroma has compelled researchers to focus on developing methods to increase their abundance. Recent research has revealed that exogenous elicitors can increase the contents of these compounds. This study determined the effects of methyl jasmonate (MeJA) preharvest treatments on the monoterpene profiles of Muscat Hamburg grapes and wine. RESULTS: A total of 27 monoterpenes were identified for Muscat Hamburg grapes and wine. The contents of most of the monoterpenes (free and glycosylated forms) in the grapes and wine increased in response to MeJA. An analysis of the expression of the genes in the terpenoid biosynthesis pathway indicated that the related biosynthetic pathways were activated by MeJA. The transcript levels of some genes were consistent with monoterpene production, including VviCSLinNer, VviGwbOciF, VviPNRLin, VviGT14 and VviUGT85A1L1. The developmental expression patterns of the VviPP2B1 and VviMYB24 transcription factor genes were positively correlated with monoterpene accumulation in ripening grapes. CONCLUSIONS: Our results suggest that MeJA may be useful for improving the aroma quality of grapes and wines. [ABSTRACT FROM AUTHOR]

BACKGROUND: Anthocyanins, a major flavonoid class, determine the color and quality of wine. Recent research revealed that basal leaf removal can increase the content of these compounds. This study determined the effects of basal leaf removal on the anthocyanin profiles of Cabernet Sauvignon grapes. RESULTS: The effects of basal leaf removal on anthocyanin composition in Cabernet Sauvignon grapes were investigated over two growing seasons. Leaf removal at 5% veraison (VB6) and at 100% veraison (VC6) was compared with a control. Reducing sugar and total anthocyanin contents in the leaf removal group were significantly higher than in the control group at harvest for both vintages. Leaf removal increased the content of individual anthocyanins and significantly improved the malvidin‐3‐O‐glucoside (Mv‐3‐glc), peonidin‐3‐O‐glucoside (Pn‐3‐glc), and malvidin‐3‐O‐(6‐acetyl)‐glucoside (Mv‐3‐acglc) content of the VB6 group. At harvest, VB6 treatment increased the transcript abundance of structural and regulator genes in the anthocyanin pathway, especially VvF3′5′H, VvLDOX, and VvDFR. CONCLUSIONS: Our results suggest that leaf removal at 5% veraison may be useful for improving the anthocyanin content in grapes. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Aspergillus carbonarius has been identified as one of the main fungi that produce ochratoxin A (OTA) in grapes. This nephrotoxic mycotoxin has been legislated against in several countries and is a major concern for viticulture. Knowledge of resistance to, or susceptibility to, colonization by A. carbonarius may be useful in selecting the most promising cultivars for organic agriculture and could help in preventing fungal contamination in vineyards. This study aimed to evaluate the colonization potential and the capacity to produce OTA by A. carbonarius in Vitis vinifera, V. labrusca, and hybrid grapes. The correlation between OTA levels and grape berry characteristics was also analyzed. RESULTS: The OTA content was only strongly correlated with the thickness and hardness of the grape skins. The correlation between OTA levels and these parameters was negative (grapes with the least thickness and hardness had the highest OTA levels). Vitis vinifera grapes were more susceptible to A. carbonarius than V. labrusca and hybrid grapes at both 25 and 4 °C. Chardonnay (V. vinifera) grapes showed the highest levels of OTA, followed by Merlot, Cabernet Sauvignon, Tannat, and Moscato Branco. Italia grapes were the exceptions among V. vinifera cultivars, since they showed similar thickness, hardness, and fungal resistance as the V. labrusca and hybrid grapes. CONCLUSION: The highest resistance to A. carbonarius was observed in the following grapes: hybrids (BRS Lorena and BRS Violeta), V. labrusca (Isabel and Bordo), and V. vinifera (Italia). These cultivars can be prioritized in the implementation of organic viticulture. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Nitrogen is involved in the winemaking process from grapevine growth to wine fermentation, and its precise utilization in vineyards can regulate grape and wine quality. Foliar nitrogen application during veraison (FNAV) could prevent nitrogen deficiency in grape and must in nitrogen‐deficient vineyards. Moreover, FNAV also could improve certain flavor components of grape and wine, but little attention has been paid to FNAV. Therefore, this paper mainly reviews the difficulties encountered in current applications of nitrogen in vineyards and wineries, and the advantages of FNAV over the addition of nitrogen in soil and wineries. And it discusses that FNAV can increase yeast‐assimilable nitrogen and phenolics, and scarcely affect volatile components of grape (must and wine), and points out the existing problems including the core issue and then puts forward future research directions. This information may indicate future directions for research, and provide a reference for viticulturists and winemakers on the precise application of nitrogen on grapevine and must to further improve grape and wine quality in nitrogen‐deficient vineyards. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The quality of wine is highly dependent on the quality of berries. Development of berries is influenced by the type and ratio of different nitrogen supplies in the soil. To understand the impact of varying sources and levels of nitrate and ammonium on sucrose and nitrogen metabolism of Vitis vinifera cv. Cabernet Sauvignon, we tested nutrient solutions with four NO3−‐N:NH4+‐N ratios (100:0, 75:25, 50:50, 0:100) through the root system. RESULTS: The form and quantity of nitrogen affected berries and leaves with source–sink relationships. Soluble sugar levels were significantly higher in plants treated with mixed nitrogen sources (75:25 and 50:50) compared to single nitrogen sources (100:0 and 0:100). In particular, treating plants with mixed nitrogen source at a 75:25 ratio resulted in 22% higher fructose levels in berries compared to the 50:50 treatment. In addition, mixed nitrogen treatments resulted in significantly higher amino acid levels and protein content. Mixed nitrogen substrates also increased the expression of enzymes involved in both nitrogen and sucrose metabolism. CONCLUSION: Plants did not maximize the nitrogen supply when single form nitrogen was provided, and the mixed nitrogen substrates consistently increased the amount of available carbon and nitrogen in the berries and leaves. We found that NO3−-N:NH4+‐N ratio of 75:25 was the optimum formula for improving nitrogen and sucrose metabolism, and reducing the competition between nitrogen and sucrose. By examining the nutrient utilization of plants cultivated with different nitrogen forms, the present study provides insights into improving cultivation and production practices. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Background: Water deficit and iron deficiency (iron chlorosis) are common environmental stresses that affect grapevine production in the Mediterranean area. Studies on the impact of both stresses, when they act simultaneously, are rare. The main objective of this investigation was to evaluate the combined effects of the incidence of iron chlorosis and the vine water status on quality of Tempranillo wine. For this, 20 non‐irrigated vineyard subzones (10 m × 10 m each), from non‐affected to moderately affected by iron chlorosis, were monitored in the Ribera del Duero area (north‐central Spain) during two consecutive seasons. Results: Factorial analyses of variance were performed to study the effects of predawn leaf water potential and foliar chlorophyll content, both measured at veraison, on chemical and sensory characteristics of wine. With an impact much greater than water status, the incidence of iron stress decreased pH of the wine and enhanced sensory attributes as tonality, layer intensity, flavour intensity, and persistence in the mouth. There were increases in red colour, astringency, and persistence of the wine associated with chlorosis, although they might be restricted in water‐deficit conditions. Conclusion: The results have demonstrated that mild to moderate iron stress can have positive effects on chemical and sensory attributes of Tempranillo wine. Measurements of foliar chlorophyll content at veraison could be very useful to map quality potential in rainfed vineyards affected by iron deficiency. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Grapevine red blotch virus (GRBV) is a recently discovered DNA virus, which was demonstrated to be responsible for grapevine red blotch disease (GRBD). Its presence has been confirmed in the United States, Canada, Mexico, and South Korea in white and red Vitis vinifera cultivars, including Chardonnay. It has been shown that the three‐cornered alfalfa treehopper (Spissistilus festinus) was able to both acquire the GRBV from a grapevine infected and transmit it to healthy grapevines in glasshouse conditions. Studies found that GRBD impacts fruit price, grapevine physiology, and grape berry composition and metabolism in red cultivars. This study evaluated the impact of GRBD on V. vinifera L. Chardonnay grape and wine composition and sensory properties from one vineyard during the 2014, 2015 and 2016 seasons. RESULTS: Grapes from symptomatic red blotch diseased grapevines were lower in total soluble solids, flavan‐3‐ol, and total phenolic content, and higher in flavonol content when compared to grapes from healthy grapevines. Wines made with grapes from symptomatic grapevines resulted mostly in lower ethanol content and higher pH when compared to wines made from healthy grapevines. Analysis of volatile compounds and descriptive analysis demonstrated that GRBD can impact wine style by altering aroma, flavor, and mouthfeel attributes. CONCLUSIONS: The impacts of GRBD on grape composition directly influenced wine chemistry. The decreased ethanol content impacted not only the levels of volatile compounds but the sensory perception during descriptive analysis. The extent of GRBD impact on the grape composition and wine composition and sensory attributes varied between seasons. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Essential oils (EOs) are volatile natural compounds produced by plant secondary metabolism, and some of them exhibit antimicrobial activity. The objective of the present study was to determine the chemical composition the EOs of Eucalyptus staigeriana and Eucalyptus globulus, and their effect in vitro and in vivo against Botrytis cinerea and Colletotrichum acutatum, the most important fungal rot diseases of grapes. Moreover, grapes collected from field experiments were used to evaluate the impact of the alternative control on the alcoholic fermentation and wine composition. RESULTS: The major compound of E. staigeriana EO were citral 30.91% (19.74% geranial, 11.17% neral), 1.8‐cineole (24.59%) and limonene (19.47%), while 1.8‐cineole represented 68.26% of E. globulus EO. The two EOs showed in vitro antifungal activity against both pathogens. Eucalyptus staigeriana EO exhibited the highest activity inhibiting mycelial growth (MG) and conidial germination at 0.5 μL mL−1. Moreover, this EO was able to reduce the incidence and severity of grey rot caused by B. cinerea and the severity of ripe rot caused by C. acutatum The alternative control did not significantly influence alcoholic fermentation, the physicochemical characteristics, and the volatile composition of wines. CONCLUSION: These results are promising and indicate that E. staigeriana EO might be further investigated as a natural alternative for the control of fungal rots on wine grapes. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Raisin is a popular snack and a common constituent of many foods owing to its good flavor and nutritional value. Conventional drying of grapes can be a slow and energy‐consuming process as their waxy surface hinders efficient moisture migration. A drying pretreatment that disrupts the waxy cuticle is usually applied to increase the drying rate. RESULTS: The application of an atmospheric‐pressure air plasma jet to the grape surface could effectively enhance the drying kinetics and decrease the drying time by more than 20%. Through etching of the waxy cuticle, the air plasma jet optimally improves the quality of the final product. Although the surface hydrophilicity was increased by 40%, the physical appearance, color, and texture of plasma‐treated raisins were similar to the product from untreated control and chemical‐treated groups. A more than twofold increase in the total phenolic content and antioxidant capacity was observed when compared to other experimental groups. CONCLUSIONS: The results indicate that atmospheric plasma could be a better option than using chemicals to pretreat grapes before drying since it leaves no toxic residue, while successfully preserving the product quality. This work shows the great potential for the application of atmospheric air plasma in the drying of food materials. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Soil and climate are among the most determining factors for the composition of grapes. Among the compounds present in grapes, anthocyanins mainly determine their organoleptic and health‐related properties. The purpose of this work was to study the influence of three different soils on the anthocyanin content of Tempranillo grapes (Vitis vinifera L.) from 2016 and 2017 vintages. The soils of the vineyards were classified as Fluventic Haploxerepts (FH), Typic Calcixerepts (TC) and Petrocalcic Palexerolls (PP). RESULTS: Non‐acylated anthocyanins, and those derived from malvidin and peonidin, were the most abundant in grapes, regardless of soil type and year. During the wetter season (2016), the grapes with the highest concentration of total anthocyanins and several of the major anthocyanins were those from TC and PP soils, in which nitrogen availability was lower than that in FH soil. However, during the drier season (2017), no significant differences were observed, although trends similar to those seen in the 2016 season were recognized. Principal component analysis showed a good separation of samples according to the two seasons and to the three soils in each season. CONCLUSION: In vineyards that resemble each other closely and that are located in a unique mesoclimatic area where similar plant material is used and similar managements practices are applied, soil characteristics, which condition water holding capacity and nitrogen availability for the vines, in conjunction with seasonal conditions, were the factors that predominantly determined the anthocyanin composition in grapes. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Drying is one of the traditional methods used for the conservation of fruits. In recent years, different methods have been developed to obtain higher quality products. Chamber‐drying methods with hot air at controlled temperature are reliable and easy to use. The effect of piercing the structure of grape berries on their drying time was studied experimentally during convective drying within a temperature range of 30–50 °C. Experimental moisture loss results were fitted to different mathematical models, evaluated for goodness of fit by comparing their respective R2, χ2, and root mean square error. RESULTS: The Midilli et al. model provided a better prediction to describe the drying of whole grapes than the other models evaluated. However, punched grapes showed a better fit for the two‐term model at 30 and 40 °C, and the approximation of diffusion model at 50 °C. The values of effective moisture diffusivity fluctuated between 8.04 × 10−12 and 7.31 × 10−11 m2 s−1. Activation energy was 56.49 and 54.43 kJ mol−1 for whole and punched grapes, respectively. All the drying processes produced an increase of total phenolic compounds and antioxidant activity in grapes, these increases being higher in whole grape drying. CONCLUSION: The drying of punched grapes was faster and the activation energy higher than with drying of whole grapes; however, whole grapes presented more total phenolic compounds and antioxidant activity. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: In wine production, temperature control is important and cooling techniques are frequently used to cool down grape must. Grape compound extraction is facilitated by enzymatic cell wall disassembly. Accordingly, our hypothesis is that the use of an alternating temperature could favor enzyme activity and thus berry compound extraction. RESULTS: White wine grapes (cvs 'Falanghina' and 'Fiano') were kept at 4 °C or at an alternating temperature (4 and 20 °C with a 6‐h interval) for 24 h. During the cooling treatment, berry skin resistance, berry firmness and native enzymes from the cell wall were analyzed; sugars, total acidity, malic acid and polyphenols were also measured. In 'Falanghina', α‐d‐glucosidase, β‐d‐galactosidase and pectinmethylesterase increased in grape berry kept at an alternating temperature, and the berry firmness decreased and the polyphenol content was greater than in the other sample. In 'Fiano', polygalacturonase and pectinmethylesterase were responsable for berry softening and, overall, with an alternating temperature, the activity was higher and, consequently, sugars and polyphenol contents were higher. CONCLUSION: Instead of just cooling wine grape, a 24‐h cycle of low and high temperature on wine grape after harvest could be used to increase cell wall enzyme activity and, consequently, decrease the berry firmness, favouring an increase in sugars and polyphenol contents. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Aspergillus is a diverse genus of fungi with high economic and social impact. Various species that belong to section Nigri (black aspergilli) are common agents of grape spoilage and potent producers of ochratoxin A (OTA), a mycotoxin associated with various nephrotoxic and immunotoxic effects in humans. Black aspergilli are difficult to classify following only phenotypic criteria; thus chemotaxonomic and molecular methods are employed in parallel with phenotypic ones for species characterization. These approaches, though accurate and replicable, require more than one individual step and are to a certain extent laborious when a rapid identification of these species is required. RESULTS: The aim of this study was to develop a high‐resolution melting polymerase chain reaction (HRM‐PCR) assay as a rapid method for identification of Aspergillus spp. section Nigri isolates and their detection in grape samples. Melt curve analysis of amplicons originating from the internal transcribed spacer 2 (ITS2) ribosomal region generated species‐specific HRM curve profiles, enabling the accurate differentiation of the analyzed genotypes. Furthermore, the assay was able to identify A. carbonarius, A. tubingensis, A. niger, A. ibericus and A. japonicus in grape samples artificially inoculated with conidia of these fungi. CONCLUSION: To our knowledge this is the first report on the development of an HRM‐PCR assay for the identification of black Aspergillus species in grape samples. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: The physiological and metabolic processes involved with grapevine growth and production are influenced by key macro‐ and micronutrients. Potassium is an essential plant nutrient that affects growth and fruit quality. In this study, the impact of foliar spraying of potassium sulfate (K2SO4) on qualitative characteristics of grape berries was evaluated in the cultivar 'Rasha', a commonly cultivated cultivar in Kurdistan province of Iran. Leaves of the fully grown vines were sprayed with each of the 1.5 and 3 g L−1 K2SO4 solutions once (1 month after petal senescence) and twice (15 days after first spraying). The control plants were sprayed with distilled water. Various biochemical contents and enzyme activities on the ripe berries were analyzed. RESULTS: Significant increases in anthocyanin, total protein content, and antioxidant enzyme activities were observed in the berries treated twice with 3 g L−1 K2SO4. Concentrations of total carbohydrate, phenol, and antioxidant activity in berries sprayed with K2SO4 were higher than in the controls. We observed a strong correlation between antioxidant activity and different phenolic compounds. CONCLUSION: These findings suggest that K2SO4 treatment influences biosynthesis of phenolic compounds and antioxidant enzymes. Thus, treatment by K2SO4 could improve nutritional and qualitative attributes of grape. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Grape withering is a process used to produce reinforced wines and raisins. Dehydration is usually carried out postharvest by keeping ripe grapes in special warehouses in controlled conditions of temperature, relative humidity (RH) and air flow. Alternatively, grape clusters can be left on the vines after the canes have been pruned. In general, dehydration increases stilbenes in grape, but there are few studies on the effects of on‐vine withering. The stilbene profiles of Raboso Piave grape during postharvest and on‐vine dehydration were studied here. RESULTS: High‐resolution mass spectrometry (MS) was used to identify 19 stilbenes, including resveratrol monomers, dimers (viniferins), oligomers and glucoside derivatives. The two dehydration methods generally had different effects on the above nutraceuticals in grape. The samples kept in warehouses revealed significant increases in Z‐ω‐viniferin, E‐ϵ‐viniferin, δ‐viniferin and another resveratrol dimer which were not observed in the plants. Trans‐Resveratrol increased significantly only in samples dehydrated in the warehouse at 21 °C and 60–70% RH. CONCLUSION: The findings increase knowledge of stilbene composition in grapes subjected to withering on‐vine. The choice of dehydration method affects the contents of these nutraceuticals in the grape and consequently in wines. Reasonably, it could also affect other secondary metabolites important for wine quality. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Monastrell is a red grape cultivar adapted to the dry environmental conditions of Murcia, SE Spain. Its berries seem to be characterized by a rigid cell wall structure, which could make difficult the winemaking process. Cabernet Sauvignon cultivar is used to complement Monastrell wines in this region owing to its high phenolic content with high extractability. This study explores the skin cell wall composition of grapes from plants resulting from intraspecific crosses of Vitis vinifera cultivars Monastrell × Cabernet Sauvignon. Moreover, the morphology of the cell wall material ( CWM) from some representative samples was visualized by transmission optical microscopy. RESULTS The total sugar content of CWM from nine out of ten genotypes of the progeny was lower than that from Monastrell. Seven out of ten genotypes showed lower phenolic content than Cabernet Sauvignon. The CWM from nine out of ten hybrids presented lower protein content than that from Monastrell. CONCLUSION This study confirms that skin cell walls from Monastrell × Cabernet Sauvignon hybrid grapes presented major differences in composition compared with their parents. These data could help in the development of new cultivars adapted to the dry conditions of SE Spain and with a cell wall composition favouring extractability. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The residue concentrations and dissipation rate of a new oxathiapiprolin fungicide in grapes and soil were investigated to provide an evaluation for the safe use of oxathiapiprolin in grapes. Pesticide residue was extracted by acetonitrile, then purified by solid-phase extraction with an Envi-Carb cartridge and determined by ultrahigh-performance liquid chromatography-tandem mass spectrometry. RESULTS The fortified recoveries ranged from 85.2% to 99.0%, with relative standard deviations of 1.7-4.5%. The limit of quantitation for oxathiapiprolin in grapes and soil was 0.002 mg kg−1. The mean initial deposits of oxathiapiprolin in grapes were 0.345-0.565 mg kg−1, with half-lives of 8.6-9.2 days. The mean initial deposits of oxathiapiprolin in soil were 0.078-0.273 mg kg−1, with half-lives of 7.6-12.0 days. The oxathiapiprolin residue in grapes and soil was 0.002-0.022 mg kg−1 and 0.002-0.123 mg kg−1 when sampling 14 days after application, respectively. CONCLUSION The residue in the grapes was less than 0.01 mg kg−1 when sampling 28 days after application, which suggested that the application rate of 20 mg a.i. kg−1 for this fungicide should be used to ensure that treated grapes can be considered safe for humans to consume when sampling 28 days after the final application. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Environmental factors have been acknowledged to greatly influence grape and wine aromas. Among them, the effect of altitude on grape aroma compounds has scarcely been debated in literature available to date. In the present study, we investigated the influence of altitude on grape composition and aroma evolution during ripening of Vitis vinifera L. cultivar Glera grown in Conegliano-Valdobbiadene DOCG area (Italy). RESULTS The site at highest altitude (380 m above sea level) was warmer than the lowest site (200 m above sea level) and, even with differences in temperature in the range 1.5-2 °C, the impact of the cultivation site on grape ripening and aroma accumulation and preservation was significant. The lowest site demonstrated slower grape ripening, and grapes at harvest accumulated lower amounts of all of the main classes of aroma compounds typical of the Glera variety. Wines produced from the highest site were preferred in tasting trials for their more patent floral notes and elegance. CONCLUSION Altitude strongly influences grape ripening evolution and flavour accumulation in the Glera grape, and this result accounts for the different styles in the sparkling wines subsequently produced. Moreover, the present study shows that aroma compound biosynthesis, particularly that of benzenoides, starts before véraison in Glera. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The interest in producing wines preferred by consumers increases the need for improving practices to modify grape and wine composition. The aim of this study was to assess the impacts of three different canopy management measures, (1) early leaf removal in the cluster zone, (2) removal of young leaves above the second pair of wires and (3) Double Maturation Raisonnée, on the yield and chemical composition of 'Istrian Malvasia' grape and wine. RESULTS Double Maturation Raisonnée had a significantly greater impact on phenolic compounds, while the highest soluble solids (24.3 and 23.5 °Brix) and titratable acidity (7.0 and 7.1 g L−1) were measured at early leaf removal. Leaf removal at véraison caused an unexpected augmentation of flavonols in the berry skin. Early leaf removal resulted in significantly lower extracts of wine. Nevertheless, they reached the highest mark (16.5 out of 20.0 points) in sensory evaluation compared with leaf removal at véraison and Double Maturation Raisonnée (15.0 points) and control (16.0 points). CONCLUSION Leaf removal at véraison and Double Maturation Raisonnée improved the phenolic composition of wine, producing a full-bodied wine. On the other hand, early leaf removal significantly augmented the yield and titratable acidity, hydroxycinnamic acids and flavanols of wine, which might have led to a fresher but less-bodied wine. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: The anthocyanin and tannin concentration and composition of Vitis vinifera L. cv. Sangiovese berries were investigated from post-veraison to harvest. Exhaustive extraction with methanol and acetone was performed to determine the total flavonoid concentration, while amodel hydroalcoholic solutionwas used to prepare extracts representing thewinemaking process. The aim of this study was to improve the knowledge of the phenolic maturity of Sangiovese grape. RESULTS: The total anthocyanin concentration increased during ripening, but the quantity of extractable anthocyanins increased more rapidly than the total. The total skin tannin concentration declined from post-veraison to harvest, whereas the extractable portion increased, with little difference in the composition of the fractions. Both the total and extractable seed tannin concentration diminished rapidly just after veraison, and only small fluctuations were detected until harvest. CONCLUSION: These results indicate that the extractability of anthocyanins and skin tannins increases during ripening, whereas there is no clear trend for seed tannins during the same period. This is the first survey to study the behavior of phenolic compounds during different steps of ripening of Sangiovese grape. [ABSTRACT FROM AUTHOR]

BACKGROUND: The gastrointestinal tract (GI) is constantly exposed to reactive species released by the GI tract itself, and those present in food and beverages. Phenolic compounds may help in protecting the GI tract against damage produced by the reactive species. In this paper we have analyzed the effects of a grape seed proanthocyanidin extract (GSPE) on reactive oxygen species (ROS) production in two different intestinal cell types: the absorptive cell line Caco-2 and the enteroendocrine cell line STC-1. RESULTS: We show that GSPE prevents tert-butylhydroperoxide-induced oxidative stress in both cell lines, and that the effects are dose and time dependent. We have also analyzed whether GSPE has any in vivo effect, and found that 25mgkg-1 body weight cannot counteract the increase in intestinal ROS induced by the cafeteria diet. However, an acute (1 h) treatment of 1 g GSPE kg-1 body weight reduced ROS in fasted animals and also decreased ROS induction by food. These effects were found only after a short-term treatment. Furthermore, we have compared the in vitro GSPE effects with those of another proanthocyanidin-rich extract from cupuassu seeds,though it has compounds with different structures. Cupuassu extract also shows antioxidant effects in both cell types, which suggests different mechanisms from those of GSPE. CONCLUSION: Natural proanthocyanidin-rich extracts have an antioxidant effect in the GI tract, acting on absorptive cells and enterohormone-secreting cells, although the effects depend on the dose and period of treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND Fourteen vineyards from two different agro-climatic regions in Spain were sampled in two consecutive years in order to determinate the grape mycobiota and diversity indexes with the final aim to define the potential mycotoxigenic species from both regions and their relationship. RESULTS The most common fungal genera encountered were Aspergillus (30.0%) , Alternaria (53.2%) , Cladosporium (11.9%) and Penicillium (2.9%) . Black aspergilli presence in the hotter region (south) was significantly higher ( P < 0.05) than in the northeast in both years. Among black aspergilli, A. tubingensis seemed to be the better adapted species to environmental conditions, while A. carbonarius was the main potentially ochratoxigenic species in both regions and years, owing to the most relevant percentage of ochratoxigenic isolates. Ochratoxin A ( OTA)-positive musts were only detected from southern vineyards, although contamination was always lower than 0.1 µg L−1. Finally, none of black aspergilli tested produced fumonisins ( FBs) on Czapek yeast extract agar ( CYA), while 63% of A. niger tested produced FB2 when inoculated on CYA20S, reaching 100% of isolates from the south. CONCLUSION Climate change scenarios in southern Europe point to an increase in temperature and drought. This could promote particularly adapted species such as A. niger, decreasing OTA risk, but this could lead to an increase in FB2 presence. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Cardiovascular disease is a leading cause of death globally. Many cardiovascular risk factors can be modified through lifestyle modification, including dietary patterns that emphasize daily consumption of a variety of fruits and vegetables. Recent observational and clinical studies suggest that flavonoids, especially those abundant in grapes and other berries, may be associated with health benefits, particularly cardiovascular benefits. Human clinical data support cardioprotective benefits of grapes through inhibition of platelet aggregation, decreased low-density lipoprotein ( LDL) oxidation, reduction in oxidative stress and improvements in endothelial function. Emerging evidence suggests that grapes may also have a favorable effect on blood lipids, decrease inflammation and reduce blood pressure in certain populations. Studies to date have shown that berries can have a beneficial effect on reducing LDL oxidation. Limited data suggest that berries may have a favorable effect on endothelial health and blood pressure. This review summarizes the current literature on human clinical studies examining the cardioprotective benefits of grapes and berries. Collectively, these data support the recommendation to incorporate products made with grapes and other berries into a heart-healthy diet. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The effects of two different operations in the vineyard (basal leaf plucking and head trimming) on the synthesis of aromatic precursors in the grape and their impact on wine aroma have been studied and compared with a control sample. The study was carried out over two consecutive years with four different varieties. Glycosidic precursors were analysed in grapes and volatile compounds were studied in the wines. ANOVA studies were performed to study the effect of the vintage, variety and treatment for each of the compounds released from their precursors. RESULTS Regarding treatment, the highest values in the concentration of free aroma compounds were achieved in the leaf plucking grapes, except for Chardonnay. Significant and positive correlations between aromatic precursors of terpenes present in grapes and their released form in wines were found for all varieties. For norisoprenoids, significant and positive correlations were exclusively found for Chardonnay and for phenols and vanillins in the year 2010 the correlations were high in three of the four varieties studied. CONCLUSION In the assays of the 2 years, more precursors were synthesised in Merlot, Gewurztraminer and Tempranillo grapes if the vineyards were plucked. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Grape brandy is a spirit drink produced by wine distillation and is matured in wooden casks. According to legislation, it can be characterised by the geographical area where the grapes were produced, the grape variety used and the selected distillation and ageing techniques. Distillation increases ethanol concentration and aromatic constituents which are already present in grapes or are developed during fermentation and distillation. During maturation in wooden casks, compounds that contribute to the aroma and taste are extracted from the wood. Hence the spirit acquires the desired softer mouth feel, aromatic complexity and overall quality. Different methods of analysis are used in order to pursuit this process by analysing volatile and non-volatile substances and correlate composition with quality. Analysis can also be useful in identification of brandy safety, potential adulterations, provenance and differentiation from other spirits drinks. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND The antioxidative effects of the traditional grape-based beverage, hardaliye, were investigated with a 40-day randomized controlled clinical trial on 89 healthy adults. Subjects were randomly divided into three groups: high hardaliye ( HH), low hardaliye ( LH) and control group. HH and LH groups consumed 500 mL and 250 mL hardaliye per day, respectively, and the control group did not consume any hardaliye. Dien conjugate ( DC), malondialdehyde ( MDA), vitamin C, total antioxidant capacity ( TAC) and homocysteine concentrations were measured in fasting blood samples collected at baseline and after intervention. RESULTS Significant decreases in DC, MDA and homocysteine concentrations were observed in HH and LH groups ( P < 0.001) after intervention, whereas the control group showed no change. The reduction in homocysteine was significantly different between HH and LH groups ( P < 0.001), except for DC and MDA. TAC and vitamin C were slightly increased; however, the change was not statistically significant. CONCLUSION Dietary supplementation with hardaliye affect the MDA, DC and homocysteine levels in blood, possibly due to the presence of antioxidant compounds. Dose response was only observed for homocysteine. Further studies need to be performed to assess the effects on antioxidant capacity. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND Sample freezing is frequently used in oenological laboratories as a compromise solution to increase the number of samples that can be analysed, despite the fact that some grape characteristics are known to change after frozen storage. However, freezing is usually performed using standard freezers, which provide a slow freezing. The aim of this work was to evaluate whether blast freezing would decrease the impact of standard freezing on grape composition. RESULTS Grape quality parameters were assessed in fresh and in frozen stored samples that had been frozen using three different procedures: standard freezing and blast freezing using either a blast freezer or an ultra-freezer. The implications of frozen storage in grape samples reported in earlier research were observed for the three freezing methods evaluated. Although blast freezing improved repeatability for the most problematic parameters (tartaric acidity, TarA; total phenolics, TP), the improvement was not important from a practical point of view. However, TarA and TP were relatively repeatable among the three freezing procedures, which suggests that freezing had an effect on these parameters independently of the method used . According to our results, the salification potential of the must is probably implied in the changes observed for TarA, whereas for TP the precipitation of protoanthocyanins after association with cell wall material is hypothesized to cause the lack of repeatability between fresh and frozen grapes. CONCLUSIONS Blast freezing would not imply a great improvement if implemented in oenological laboratories, at least for the parameters included in this study. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]