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Abstract: Galicia (the north-western corner of Spain) is a Spanish region with several old-traditional winegrowing areas. Vitis vinifera L. cv. Mencía is one of the most often used to produce quality red wines but the tendency of the world wine-making market is to reward the production of wines that have particular and differentiated characteristics. In Galicia, there are other red cultivars such as Gran Negro which were not exploited for their potential to produce quality red wines. Dynamics of anthocyanin and flavonol accumulation in Gran Negro berries were studied separately in two different positions within the cluster (tips and shoulders) during 30days before harvest to assess the existence of different polyphenol quality in both positions and as a consequence, red wines with different qualities. Dynamics of anthocyanins over ripening confirmed that anthocyanins presented upward trends (from 1510 to 1727mg/kg in tips; and from 1532 to 1728mg/kg in shoulders) but dynamics of flavonols confirmed that maximum values were reached and stabilised thirty days before harvest (from 45 to 39mg/kg in tips; and from 49 to 45mg/kg in shoulders). No differences were observed in anthocyanin and flavonol contents collected from tips and shoulders which indicates that is not necessary to harvest them separately. The results from Gran Negro were compared with those of Brancellao and Mouratón. [Copyright &y& Elsevier]

Natural sweet wines are mainly characterised by their high sugar concentration which can be achieved by over-ripening of grapes and/or a previous process of grape dehydration. Although the quality of these sweet wines is determined essentially by aroma compounds, few reports on phenolic compounds and colour of sweet wines have been published. Phenolic composition and colour of natural sweet wines are described now in this review from two points of view: influence of drying or dehydration process on colour and phenolic composition of grapes for producing natural sweet wines; and also, influence of grape sugar process on colour and phenolic composition of their respective sweet wines. Grapes and wines are simultaneously grouped according to the dehydration -on or -off-vine. The grape drying process should be studied in greater depth to know mechanisms involving phenolic compounds that directly affect the colour, stability and ageing of natural sweet wines. [Copyright &y& Elsevier]

Abstract: The opportunity for obtaining different wines from the same variety cultivated in the same vineyard is becoming of increasing importance. This is why some wine cellars have started to assay the separation of the tips and shoulders berries of the clusters of a specific variety with this objective. In this work, the study is focused on berries of Mouratón (Vitis vinifera L.) to investigate if, in the latter stages of ripening, differences exist in the probable alcoholic degree, total acidity of the must, as well as in the aromatic composition of skin and flesh of berries coming from the tips and shoulders of the clusters. Gas chromatography coupled to mass spectrometry (GC–MS) was used to determine the aromatic composition. The obtained results showed that there was not variability for the probable alcoholic degree and total acidity between the tips and shoulders, whereas there was variability for their aromatic composition during ripening. These results are promising for those wine cellars that are considering the separation of berries from tips and shoulders of the clusters for the elaboration of different quality wines. [Copyright &y& Elsevier]

Abstract: Cyazofamid, famoxadone, mandipropamid and valifenalate are new fungicides recently proposed to control downy mildew (Plasmopara viticola) in vines. In this study, three of them were applied in an experimental vineyard producing white grapes (Vitis vinifera cv. Godello) as commercial formulations: Mildicut (2.5% cyazofamid), Equation Pro (22.5% famoxadone+30% cymoxanil) and IR-5885 (6% valifenalate+60% mancozeb), meanwhile mandipropamid was directly applied as an active substance. The last treatments to control this disease were made out under critical agricultural practices, without obeying the preharvest interval. Besides the above products, the control of powdery mildew (Erisiphe necator) and grey mould (Botrytis cinerea) was made by employing standard commercial formulations. Once treated white grapes were harvested, the fate of all these fungicides from vine to wine was studied. Residues of cyazofamid, famoxadone and valifenalate in grapes were higher than their EU MRL, except for mandipropamid. The white wine-making process allowed the dissipation of fungicide residues in high percentages (ca. 95%), except for valifenalate that remained in wine at 32%. [ABSTRACT FROM AUTHOR]

Grapes from Vitis vinifera var. Tempranillo and Graciano of La Rioja (North Central Spain) were vinified after addition of two fungicides (mepanipyrim and fenhexamid) at concentrations corresponding to their MRLs. These fungicides are commonly used in the vine growing to control botrytis disease. The fungicide effect throughout winemaking on the volatile composition and aroma profile of the final wines was evaluated, together with the level of fungicide residues in the final wines that were found to be safe for consumers. Concentrations of C 13 -norisoprenoids in Graciano wines obtained after the addition of both active substances showed the greatest variations with respect to control wine; whereas the concentration of volatile compounds in Tempranillo wines were seemingly unaffected by the presence of fungicide residues. On the other hand, the aroma profile of monovarietal red wines was evaluated by using odorant series which included volatile compounds with similar odour descriptors. In this sense, supplementation with the antifungals seemed to increase the OAV for the ripe fruit series with respect to the control wines in Graciano wines. [ABSTRACT FROM AUTHOR]

Abstract: Sweet wines are traditionally elaborated in Galicia (the N.W. corner of Spain). The denomination of origin (DO) Valdeorras, one of the five DOs in Galicia, wants to promote the production and marketing of new sweets wines. The first one is made with dried red grapes Vitis vinifera L. Garnacha Tintorera (GNSW); this cultivar is a teinturier cultivar which has excellent potential to produce wines from raisined grapes. The second one, a fortified sweet wine aged in oak barrels (GFSW). Additionally a dry young wine (GBW) was produced from the same variety. Their aroma profiles and chromatic characteristics (determined by simple spectrophotometric methods) have been previously established. Now, proanthocyanidins, flava-3-ol monomers, anthocyanins, phenolic acids, flavonols and resveratrol were determined by HPLC, for the same three wines. The highest concentration of total proanthocyanidins (PAs) was evaluated in the GBW (525mgL−1), which was about 2-fold the concentration in the GNSW (236mgL−1) and about more 10-fold the concentration in the GFSW (44mgL−1). No apparent difference in the aDP (mean degree of polymerisation) was observed for the GBW (1.9) and the GNSW (2.1), whereas a slightly lower value was obtained for the GFSW (1.5). Total anthocyanin concentration was described as follow as GBW: 390mgL−1 ≫GNSW: 57mgL−1 >GFSW: 25mgL−1, which indicates that sweet wines were polymerised in great extent. Only vitisin A and B were found the main concentration in GFSW when compared to GBW by the ageing process. In sweet wines, phenolic acids (hydroxybenzoic and hydroxycinnamic acids) and flavonols were lowest when compared to GBW and resveratrol not was found in sweet wines. [Copyright &y& Elsevier]

Abstract: The postharvest dehydration is one of the most important steps in obtaining a high quality naturally sweet wine and it can play an important role in modulating the production and the release of volatile compounds. However, only a few studies have analysed the changes in the free and bound volatile compounds of grapes throughout the process. In this work, GC–MS was applied to determine the aromatic composition of Garnacha Tintorera grapes subjected to off-vine dehydration or raisining at several points during the process. The total water loss in 83days was about 62% and the sugar concentration rose from 225 to 464g/L. Within the free volatile compounds, isoamyl alcohols, benzaldehyde and guaiacol registered the largest increase above the concentration effect due to water loss; while within the bound volatile compounds were isoamyl alcohols, ethyl vanillate and benzoic acid. The aromatic profile of the raisins obtained were mainly caramelised, floral, phenolic and burned. [Copyright &y& Elsevier]

Abstract: Within the framework of a more and more competitive market, the opportunity to obtain different wines from the same variety cultivated in the same vineyard is becoming of increasing importance. In this study the presence of aroma compounds in Gran Negro (Vitis vinifera L.) grapes was investigated in order to obtain its aroma potential fingerprint taking into consideration the separation of apical (tips) and basal (shoulders) berries of the clusters. In the final stages of maturation, differences were searched in the probable alcohol content, total acidity of the must, as well as in the aromatic composition of skin and flesh from shoulder and cluster tip berries. A GC–MS method was used to determine the aromatic composition. The obtained results showed that there was variability for their aromatic composition. These results are promising for those wine cellars that are considering the separation of berries from tips and shoulders of the clusters for the elaboration of wines with different qualities. For the berries from the tips of the clusters, aromatic alcohols and volatile phenols were mainly found in the flesh (15 and 2 times higher than in the skin, respectively); whereas aldehydes and C6 alcohols were mainly in the skin (4 and 3 times higher than in the flesh, respectively). For this reason, it could be recommended to separate berry skin before enzymatic maceration of the berry flesh must. For the berries from the shoulders of the clusters, the group of volatile phenols showed 2 times more concentration in the skin than in the flesh; it could be recommended to maintain berry skin during enzymatic maceration of the must. Overall, the tips showed a 40% lower level of C6 alcohols (contributing to herbaceous nuances). These results from Gran Negro were compared with those of Brancellao and Mouratón cultivars. [Copyright &y& Elsevier]

Abstract: In this study the presence of aroma compounds in grapes of Brancellao (Vitis vinifera L.) was investigated in order to obtain its aroma potential fingerprint. It is well known that differences exist in aromatic compounds amongst grapevine varieties at ripening stages. Within the framework of an increasingly competitive market, the chance of obtaining different wines from vines of the same variety grown at the same vineyard is becoming of increasing importance. This can be done through the managing of the vineyard, but also some wineries have assayed the separation of the tip and shoulder berries of the clusters of a specific variety with this objective. In this work it is evaluated that, in the final stages of maturation, differences exist in the probable alcoholic degree, total acidity of the must, as well as in the aromatic composition of skin and flesh of berries coming from the tips and shoulders of the clusters. Gas chromatography coupled to mass spectrometry (GC–MS) was used to determine the aromatic composition, in the skin and flesh of each sample, either tip or shoulder berries from the clusters. The obtained results showed that there was not variability for the probable alcoholic degree and total acidity between the shoulders and tips, whereas there was variability for their aromatic composition. For the berries from the tips of the clusters most of volatiles were found in the flesh (except aldehydes) and spicy and floral nuances (with the only exception of β-ionone) were in higher proportions. For the berries from the shoulders of the clusters, most of volatiles were found in the skin (monoterpenes, norisoprenoids, aldehydes, and C6 alcohols), where the flesh was slightly richer in aromatic alcohols, volatile phenols and pantolactone; β-ionone and herbaceous nuances were in higher proportions. These results are promising for those wineries that are considering the chance of separating berries from tips and shoulders of the clusters for the elaboration of different quality wines. [Copyright &y& Elsevier]

Abstract: Cyazofamid, famoxadone, mandipropamid and valifenalate, four new fungicides for controlling downy mildew in vine, were applied to an experimental vineyard producing Vitis vinifera white grapes of the Godello variety. Following harvest, the grapes were subjected to single vinification runs. The odour activity values (OAVs) for the Godello white wines obtained were estimated with a view to assessing potential alterations of their aroma composition by effect of the phytosanitary treatments. Several fatty acids, their esters and acetates were formed during the winemaking process in high levels and could be expected to strongly influence the aroma of the wines by introducing floral, fruity and spicy nuances. The concentrations of six compounds (2-phenylethyl acetate, ethyl butanoate, ethyl octanoate, 4-vinylguaiacol, 3-methylbutanoic acid and methionol) were found to suffice with a view to discriminating between wines from grapes treated with fungicides under Critical Agricultural Practices (CAP) and under Good Agricultural Practices (GAP). [Copyright &y& Elsevier]

Abstract: Tebuconazole is a triazole fungicide used in the treatment of diseases of vinification grapes. In this work, Mencía red grapes harvested in Valdeorras (Ourense, NW Spain) were used in three vinification experiments performed in an experimental cellar. Experiment A was conducted on uncontaminated crushed, destemmed grapes and involved inoculation with commercially available yeasts at the beginning of alcoholic fermentation. In experiments B and C, crushed, destemmed grapes were spiked with a pure standard of tebuconazole and inoculated with commercial yeasts (experiment B) or endogenous yeasts (experiment C). The main volatile compounds responsible for the aroma composition of the resulting wines were determined in order to evaluate the influence of tebuconazole residues on the outcome of the winemaking process. Terpene and higher-alcohol concentrations were essentially similar in the three wines; by contrast, C6-alcohol, ester and aldehyde concentrations differed significantly between them. [ABSTRACT FROM AUTHOR]

Abstract: The removal of tebuconazole residues during the winemaking process, applied initially to red must elaborated from Mencía variety grapes from A.O.C. Valdeorrras (Ourense, N.W. Spain), was studied. Analytical determination of tebuconazole residues in grapes, musts and wines were perfomed by gas chromatography equipped with an ion trap mass spectrometry detector (GC–ITMS). Tebuconazole is retained on the solid matter (cakes and lees) and clarification agent. The eliminated percentage of tebuconazole in the final wine is 86%. The influence of this fungicide on the fermentative activity of Saccharomyces cerevisiae yeast and the Oenococcus oeni was also studied through in vitro assays. Liquid chromatography equipped with triple quadrupole mass spectrometer (LC–MS/MS) was used to determine tebuconazole residues in synthetic must and wine used for in vitro assays. No effect on the alcoholic or malolactic fermentation was observed; and no degradation of tebuconazole originated by these microorganisms was registered. [Copyright &y& Elsevier]

Abstract: The agronomic utility of a solid waste, waste bentonite (WB), from wine companies was assessed. In this sense, the natural characteristics of the waste were measured, followed by the monitoring of its effects on the adsorption/desorption behaviour of three quaternary herbicides in acid soils after the addition of increasing levels of waste. This was done with the intention of studying the effect of the added organic matter on their adsorption. The high content in C (294gkg−1), N (28gkg−1), P (584mgkg−1) and K (108gkg−1) of WB turned it into an appropriate amendment to increase soil fertility, solving at the same time its disposal. WB also reduced the potential Cu phytotoxicity due to a change in Cu distribution towards less soluble fractions. The adsorption of the herbicides paraquat, diquat and difenzoquat by acid soils amended with different ratios of WB was measured. In all cases, Langmuir equation was fitted to the data. Paraquat (PQ) and diquat (DQ) were adsorbed and retained more strongly than difenzoquat (DFQ) in the acid soil studied. However, the lowest retention of DFQ in an acid soil can be increased by amendment with organic matter through a solid waste from wineries, and it is enough for duplicate retention a dosage rate of 10t/ha. Anyway, detritivores ecology can still be affected. Detritivores are the organisms that consume organic material, and in doing so contribute to decomposition and the recycling of nutrients. The term can also be applied to certain bottom-feeders in wet environments, which play a crucial role in benthic ecosystems, forming essential food chains and participating in the nitrogen cycle. [Copyright &y& Elsevier]

Abstract: Various analytical methods based on the HPLC-DAD technique were used to determine 38 phenolic compounds in red wines. While anthocyanins and hydroxycinnamic acids were determined by direct injection of wine samples, hydroxybenzoic acids, catechins, procyanidins and flavonols required an analytical pretreatment involving liquid–liquid partitioning with ethyl ether followed by solid-phase extraction on C18 mini-columns. The proposed analytical methods were used to establish the phenol composition of Mencía and Brancellao, two varietal young red wines, and its influence on colour stability during storage in bottles for one year. At the end of malolactic fermentation, Mencía wine was found to contain much greater amounts of anthocyan pigments than was Brancellao wine. This resulted in a higher colour density but a weaker hue in Mencía wine than in Brancellao wine. Phenolic compounds evolved similarly in both wines during storage; changes in such compounds involved a decrease in the levels of monomeric anthocyanins, phenolic acids, epicatechin and flavonols, and an increase in those of procyanidins. The absence of a relationship between the changes in colour density and monomeric anthocyanins in both wines suggests that copigmentation and polymerization with other phenolic compounds (viz. phenolic acids, catechins and/or flavonols) prevail over degradation of the pigments. [Copyright &y& Elsevier]

A solid-phase microextraction (SPME) followed by a gas chromatographic–mass spectrometric (GC–MS) determination has been developed and validated for the determination of cyprodinil and fludioxonil in white wine samples. Extraction parameters such as the selection of SPME coating, the effect of the temperature, the effect of the headspace volume and the salt addition were studied and optimized, together with GC–MS analytical conditions. The divinylbenzene–Carboxen–polydimethylsiloxane (DVB–CAR–PDMS) fiber was the most appropriate for the determination of the two pesticides in wine. The quality parameters of the proposed method demonstrated a good precision (RSD about 5%), with detection limits of 0.1 and 0.2 μg/l for cyprodinil and fludioxonil, respectively. Fifteen commercial white wine samples produced in Rı´as Baixas area in Galicia (N.W. Spain) were analyzed with the SPME–GC–MS procedure. Some of the commercial wines (75%) presented the two pesticides in concentrations ranging from 0.9 to 28.6 μg/l. In conclusion, SPME–GC–MS has a great potential for fungicide determination in wines. [Copyright &y& Elsevier]