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Aroma is an identifying characteristic of wines and is of crucial importance for the consumer appreciation. Among all odour-active compounds, some key molecules appear only after ageing and give a strong contribution to both identity and added value of the wine bottle. Methyl salicylate (MeSA) is an odorant which usually appears after ageing and could provide an increase in fruity aromas and freshness. This odour-active ester can be found mainly bound to one or more carbohydrates, forming a glycoside. In wines, the hydrolysis of glycosides contributes to the aroma evolution of wine. In our previous works, MeSA was found in relevant content, both in bound and free form, in some genetically related Italian varieties such as Trebbiano di Lugana, Trebbiano di Soave (both employed in the production of Lugana wines), and Verdicchio. In this research, a straightforward filter-and-shot LC-MS/MS method was used for the determination of 7 different MeSA glycosides in 246 samples representative of 18 different monovarietal Italian white wines. MeSA glycosides were found in relevant concentrations in Verdicchio and Lugana wines, whereas they were determined for the first time in all others. Results were in accordance with the literature since Lugana and Verdicchio emerged for the total amount of glycosides, together with Erbaluce, whose richness was not known to date. This trend was observed for all analytes, with stronger intensity, especially in MeSA–glucoside, MeSA–gentiobioside and MeSA–violutoside. The triglycosylated form was not detected in any case. The same trend was also observed for the free form, whose value was not above the olfactory threshold for any sample. MeSA in all its forms also showed a qualitative trend, with MeSA - glucoside and MeSA–primeveroside emphasised in richer cultivars with also a characteristic pattern. The knowledge of the concentration of MeSA glycosides could be considered a potential predictor of the potential evolution of white wines towards balsamic-like nuances.

Astringency is an essential sensory attribute of red wine closely related to the saliva precipitation upon contact with the wine. In this study a data matrix of 52 physico-chemical parameters was used to predict the Saliva Precipitation Index (SPI) in 110 Italian mono-varietal red wines using partial least squares regression (PLSr) with variable selection by Variable Importance for Projection (VIP) and the significance of regression coefficients. The final PLSr model, evaluated using a test data set, had 3 components and yielded an R2test of 0.630 and an RMSEtest of 0.994, with 19 independent variables whose regression coefficients were all significant at p

This work aimed to investigate the occurrence of different monoterpenoids and norisoprenoids in 10 monovarietal Italian red wines (Aglianico, Cannonau, Corvina, Montepulciano, Nebbiolo, Nerello, Primitivo, Raboso, Sangiovese and Teroldego) from 12 regions across Italy. The wines were produced in their terroirs following the oenological practices and legislation of the respective appellation. Data showed that different wine varietals were characterised by peculiar profiles of monoterpenoids and norisoprenoids. Montepulciano and Cannonau wines showed highest levels of nerol, terpinolene, α-terpineol, limonene and of the norisoprenoids β-damascenone, α-ionone, TPB, TDN and vitispirane. Aglianico, Corvina, Nebbiolo and Primitivo were characterised by relatively high levels of linear monoterpene alcohols such as linalool and geraniol. Sangiovese samples from Tuscany could be differentiated from those of Romagna, with the former characterised by a higher content of α-terpinene and the latter of γ-terpinene. The monoterpene 1,4-cineole was present in Montepulciano, Raboso and Sangiovese at potentially relevant olfactory levels, its occurrence associated with higher content of terpinen-1-ol acting as a potential precursor under wine acid conditions.

While red wine phenolics have been extensively studied, polysaccharides and proteins have not received the same level of attention, especially when considering Italian wines. In this study, for the first time, quantitative and qualitative data on the macromolecular (proteins and polysaccharides) and tannin composition of 110 monovarietal red wines from 11 of the most important Italian grape varieties are reported. The winemaking did not include any filtration, oak contact, fining treatments, or ageing on yeast lees. Results highlighted a great inter- and intra- varietal diversity. The protein content ranged between 0 and 159 mg/L, polysaccharides between 211 and 1081 mg/L and total tannins between 171 and 3746 mg/L, with averages of 41 mg/L, 497 mg/L and 1687 mg/L, respectively. Six varieties with protein content representative of the variability observed were selected and submitted to electrophoresis. Within each variety, the SDS-PAGE mobility of protein-tannin complexes was similar but showed two distinct patterns for wines of different varieties (higher mobility for Corvina, Teroldego and Raboso Piave, lower mobility for Nebbiolo, Aglianico, Cannonau), suggesting that the Italian monovarietal wines can be diverse also in their colloidal-forming structures. This can be explained by looking at the different percentages of protein-reactive tannins (TBSA) on the total tannin content (TMCP), which is a varietal characteristic.

(1) Torymus sinensis, the biocontrol agent of the Asian chestnut gall wasp Dryocosmus kuriphilus, is univoltine, but in NW Italy a small percentage of individuals exhibits a prolonged diapause, mainly as late instar larva. (2) In 2020, the diapause was investigated to evaluate its trend over the years. Due to the low survival rate of diapausing T. sinensis adults, the seasonal variation in the galls’ toughness was evaluated, thus assuming that dry galls over time can negatively affect emergence. The window of vulnerability of the gall wasp galls was also evaluated in controlled conditions. (3) The results showed that the average number of second year T. sinensis emerging per 100 cells was 0.41 ± 0.05, and dead adults accounted for 4.1 ± 0.23 per 100 cells. Gall toughness resulted in lower values for galls collected in May and June, and then gradually increased over time. In general, no difference was detected in the wall toughness of galls formed during the previous year when compared to current-year dry galls. Oviposition was recorded on all the tested galls collected in May and June, and no difference in the number of oviposition events was detected. Conversely, no oviposition was observed in July. Comparing the number of oviposition events by T. sinensis and the gall toughness, a negative correlation was found (R2 = −0.99). (4) The present findings contribute descriptive information on this gall’s structural traits, and the influence on gall wasp management is also discussed.

The study of the psychological effects of social media use on adolescents’ adjustment has long been the focus of psychological research, but results are still inconclusive. In particular, there is a lack of research on the positive and negative developmental outcomes and on possible moderating variables, especially concerning early adolescence. To fill these gaps in literature, the present study longitudinally investigated the relationships between social media use, depressive symptoms, affective well-being and life satisfaction, as well as the moderating role of emotional self-efficacy and gender. The study involved 336 Italian early adolescents (mean age = 13, sd = 0.3; 48% girls) who completed an anonymous self-report questionnaire twice within a year. Main results showed that higher social media use was related to higher depressive symptoms, lower affective well-being and lower life satisfaction among girls with lower emotional self-efficacy. Conversely, high social media use was related to higher affective well-being and higher life satisfaction for girls with higher emotional self-efficacy. Results are discussed in relation to their implications for risk prevention and health promotion among early adolescents. In particular, our results suggest that promoting emotional self-efficacy can be very helpful in making the use of social media an opportunity for well-being and life satisfaction rather than a developmental risk.

Berry texture and berry skin mechanical properties are traits with high agronomic relevance, because they are related to quality parameters and marketing requirements of wine, table, and raisin grapes. Searching for QTLs linked to berry texture, a F1 population of 152 individuals and their parents were used in this study. These F1 plants were obtained crossing ‘Raboso Veronese’, a seeded black wine grape cultivar and ‘Sultanina’, a seedless white grape variety, especially used for raisins. Density flotation was applied for berry sorting improving the management of many and highly variable genotypes, irrespective to the quantification of specific molecules classes. Berries were evaluated for technological ripeness parameters and mechanical properties. Texture parameters were taken as raw data and as data normalized on berry dimensions, i.e. berry diameter or surface or volume. SSR molecular markers were used to produce a genetic map and a major, strong QTL for berry texture was found on chromosome 18 with traits related to berry ‘firmness’ showing a phenotypical explained variance higher than 60%, and traits related to berry resilience, springiness and cohesiveness showing a variance higher than 50%. Surprisingly, this QTL showed to be associated with SSR markers linked to VvAGL11, the main gene linked to seedlessness. VvAGL11 expression and co-expression profiling during grape ripening was evaluated using available information; this data suggested a role for this gene on the texture of a ripe berry.

Anthocyanins are extracted from grape skins during maceration and are responsible for the red colour of wine. Their contribution to in-mouth sensations is mainly related to their interactions with condensed tannins, which are largely responsible for wine astringency and mouthfeel-related features. Recently, the influence of several groups of polyphenols, together with other relevant non-phenolic wine constituents,was investigated in terms of their ability to modify the sensory perception of condensed tannins. The aim of this study was to investigate the influence of three acylation groups of anthocyanins (glucoside, acetylglucoside, and p-coumaroylglucoside) extracted from grape skins on in-mouth related features. An extract of total anthocyanins and their individual fractions were tasted using different sensory approaches (triangle test, check-all-that apply and descriptive analysis) and compared to polyphenols extracted from grape skins and seeds. The investigated sensations were overall astringency and astringency sub-qualities, which were divided into two groups: sensation during tasting (in-mouth, particulates) and sensation after expectoration (surface smoothness). Bitterness was also studied. Anthocyanin fractions were added to skin and seed extracts and tasted as mixtures to find out if anthocyanins modify in-mouth perception. Although the anthocyanin fractions showed a low sensory impact, total anthocyanins and the glucoside fraction were perceived at the concentration ranges found in wines (400 mg/L), and they were found to influence astringency intensity and soft astringency sub-qualities, such as “velvety” and “chalky”. The addition of glucoside anthocyanin (400 mg/L) to skin and seed extract (1000 mg/L) modified in-mouth perception; in particular, seed extract was perceived as being more astringent and was characterised by harsher astringency sub-qualities (surface smoothness and particulates). In contrast, the addition of glucoside anthocyanin to the skin extract led to lower surface smoothness, although the intensity of overall astringency was unchanged. These results confirm that the presence of anthocyanins can modify the perception of in-mouth sensations and interact to different extents with other polyphenols, thus leading to the modification of the intensity of astringency and its sub-qualities.

Viticulture is a cropping system in which treatment against fungal diseases (in particular powdery and downy mildews) can be extremely frequent. Accordingly, a reduction in antimicrobial treatments and the application of environmentally-friendly compounds are becoming increasingly important for a more sustainable viticulture. In addition to their effect against pathogens, the impact of these products on the quality of the grapes is very important for the oenological industries, but unfortunately at present few data are available. We evaluated the effect of the application of biocontrol products and resistance inducers in the vineyard on the mechanical properties, microbial ecology, technological and phenolic maturity of Vitis vinifera “Nebbiolo” grapes at harvest. The yield and vigor of vines were not influenced by the treatments, nor were the production of primary and secondary metabolites. However, the active ingredients influenced the mechanical properties of the skin (hardness and thickness). A significant hardening of the skin was detected when laminarin and chito-oligosaccharides were used, and sulfur induced a thickening of the skin with potential consequences for wine quality. Furthermore, the yeast community present on grape berries was influenced by the treatments. The abundance of Aureobasidium pullulans, the dominant species on the grape berry, changed in response to the compounds used. In addition, Alternaria sp. was reduced in some treatments with a potentially positive effect on the quality and the safety of the grapes. This study provides an overview of the effect of biocontrol products and resistance inducers on microbial ecology and “Nebbiolo” grape quality, contributing to the establishment of more sustainable and effective defense strategies in viticulture.

Aim: In this work, seven strains of Starmerella bacillaris were analysed for their ability to release polysaccharides during alcoholic fermentation (AF), both in single-strain and in sequential AF together with Saccharomyces cerevisiae. Methods and Results: A synthetic polysaccharide-free must was used to characterise the mannoproteins (MPs) released. The MPs were quantified, characterised in terms of carbohydrate composition, and tested to assess their ability to reduce protein and tartrate instabilities and their ability to affect the foaming properties of wine. Conclusions: All the tested strains in sequential AF increased the total MPs production. Moreover, the strains affected the MPs properties in different ways regarding tartaric and protein stabilities. The MPs released in sequential AF by some S. bacillaris strains showed a significant effect on protein stabilisation and tartaric stability. An effect on the foamability was found for MPs obtained in single-strain AFs of S. bacillaris. Significance and impact of the study: An improvement in wine stability can be achieved using the sequential AF.

The chemical composition of Romanian table grape varieties was determined to evaluate their phenolic and aroma profiles because they are factors useful for the variety characterization and consumer acceptance. Two white table grapes (‘Aromat de Iaşi’ and ‘Timpuriu de Cluj’) and two red table grapes (‘Napoca’ and ‘Someşan’) were studied. The phenolic composition of berry skins and seeds was determined using spectrophotometric methods. The profile of anthocyanins and hydroxycinnamoyl tartaric acids (HCTs), and the content of trans-resveratrol were determined in the skins using high-performance liquid chromatographic (HPLC) methods. Free volatile compounds were quantified by gas chromatography/mass spectrometry (GC/MS). A different phenolic and aromatic composition was found in the varieties studied. Among white grapes, ‘Aromat de Iaşi’ stands out for the great number of aroma compounds, and ‘Timpuriu de Cluj’ showed high contents of polyphenols, particularly oligomeric flavanols in skins and seeds (1,171 and 1,189 mg kg-1, respectively) and total skin HCTs (181.6 mg kg-1). The red variety ‘Napoca’ had high contents of total anthocyanins (380 mg kg-1) and total skin HCTs (183.2 mg kg-1), and it is characterized by high percentages of acylated anthocyanin derivatives (28.5%) and trans-caffeoyltartaric acid forms (58.8%). ‘Someşan’ grapes showed high contents of free volatile compounds, particularly of 1-hexanol, (Z)-3-hexen-1-ol and (E)-2-hexenoic acid (167.0, 59.4 and 167.0 µg kg-1). These results may contribute to the knowledge of Romanian table grapes perspective and to a better exploitation of these varieties.

In winemaking, oenological tannins are used to preserve wine colour by enhancing the antioxidant activity, taking part in copigmentation, and forming polymeric pigments with anthocyanins. As a novel processing aid, in this study, a biosurfactant extract was evaluated as a solubilizing and stabilizing agent of anthocyanins in red wine. The biosurfactant extract under evaluation was obtained from a fermented residual stream of the corn milling industry named corn steep liquor (CSL). Two red winegrape varieties (Vitis vinifera L. cv. Aglianico and Cabernet sauvignon) were studied for anthocyanin content and profile, and colour traits, during simulated skin maceration for 7 days at 25 °C, as well as polymerization and copigmentation at the end of maceration. A model wine solution was used as a control, which was added either with the CSL biosurfactant or with four different oenological tannins (from grape skin, grape seed, quebracho, and acacia). The results showed that CSL biosurfactant addition improved the colour properties of skin extracts by the formation of more stable compounds mainly through copigmentation interactions. These preliminary results highlighted that the effectiveness of CSL biosurfactant is variety-dependent; however, there is no significant protection of individual anthocyanin compounds as observed for delphinidin and petunidin forms using quebracho tannin.

The aim of this study was to evaluate the influence of paper bagging of grape bunches on the morphological, mechanical, and chemical characteristics of berries of three table grapes varieties as an environmentally-friendly technique for protecting clusters from biotic and abiotic agents. Clusters of Italia, Autumn Royal, and Regal Seedless grape cultivars were bagged and compared to a not-bagged control. Air temperature inside and outside the bags was monitored. Bunch weight and length, number of berries per bunch, berry longitudinal and transversal diameter, berry mass, number of seeds per berry (normal in size and aborted), soluble solid content, titratable acidity, and skin color by CIEL*a*b* parameters were determined on four points of each berry. Berries were evaluated using texture analysis, and the main texture profile analysis parameters were compared. The air temperatures around not-bagged clusters were slightly higher than inside the bags. In all the cultivars under evaluation, bagged bunches were heavier compared with not-bagged ones. In Autumn Royal and Regal Seedless, these differences were mainly owing to the higher number of berries and higher berry weight of the bagged bunches. Regarding mechanical properties, in seedless varieties, the bagging treatment increased berry hardness (related to the berry firmness) and decreased berry cohesiveness and resilience, whereas an opposite behavior was found in cv. Italia. Berry skin break force was lower in the bagging treatment in all the analyzed varieties, indicating a softer and easier-to-chew berry skin. The findings demonstrate that the bagging technique affected the three variety parameters to different extents. The main differences were found in the seedless varieties in terms of berry size and bunch characteristics. For all varieties, bagged bunches achieved the quality level required by the market, confirming the suitability of this technique. However, the bag industry is proposing many different bag types (differing in material, shape, color, and closing system); therefore, further studies are needed to obtain more complete and exhaustive technical information.

A dehydration experiment was carried out on Vitis vinifera L. cv Muscat of Alexandria (synonym Zibibbo) following the process for the production of renowned special dessert wines produced on Pantelleria island (Sicily, Italy). Harvested berries were pre-treated in a sodium hydroxide dipping solution (45 g/L, dipped for 185 s, 25 °C) to accelerate the drying process, rinsed, and dehydrated in simulated conditions (relative humidity 30%, 30 °C temperature, air speed 0.9 m/s). Three dehydration levels were achieved, corresponding to “Passolata”, “Bionda”, and “Malaga” stages (35%, 50%, and 65% of weight loss, respectively) of the Pantelleria denomination of origin (DOC). Grape skin mechanical properties, technological parameters, phenolics, and aroma profile varied considerably during dehydration. The most important aroma compounds for their olfactory impact, such as linalool, geraniol, nerol, and citronellol, especially in glycosylated forms, significantly increased in dried grapes compared to fresh ones, even if aroma profile modification occurred. A decrease in break skin force could have induced higher release of flavonoids. The findings showed relevant changes, allowing winemakers to better select the ratio of fresh and dehydrated grapes in the function of the final desired wine.

Ozone has been recently recognized as an efficient sanitizing agent in wine industry because of its powerful oxidizing properties. Furthermore, postharvest treatments of grapes with ozone can stimulate defense responses by synthetizing secondary metabolites against oxidative stress. In this study, the effect of postharvest short-term ozone treatments was assessed for the first time on free and glycosylated volatile organic compounds (VOCs) of winegrapes. Two different ozone concentrations (30 and 60 μL/L) and exposure times (24 and 48 h) were investigated just after treatment (fresh grapes) and after partial dehydration up to 20% weight loss (withered grapes). The study was carried out on Moscato bianco winegrapes (Vitis vinifera L.) due to the importance of terpenes in white aromatic cultivars to produce high quality wines. The results obtained showed that short-term ozone treatment caused a significant decrease in total contents of free VOCs in fresh grapes, mainly due to terpenes. Among them, linalool, geraniol, and nerol are the major aromatic markers of Moscato bianco grapes. Ozone entailed a significant decrease of free linalool contents in fresh grapes, the less stressful ozone treatment showing the smaller linalool degradation. However, the stronger and longer ozone treatment induced the synthesis of this compound probably in response to higher abiotic stress. Instead, significant changes were not observed in geraniol and nerol contents in fresh grapes. This last ozone treatment also reduced the loss of free linalool by water loss in withered grapes even though total VOCs and terpenes remained relatively stable. Furthermore, ozone seems to promote the synthesis of free (+)-4-carene and 4-terpineol in withered grapes under certain treatment conditions. Regarding glycosylated compounds, total VOCs and terpenes were less sensitive to ozone. Our findings highlight that ozone can be used as sanitizing agent in aromatic grape varieties prior to winemaking without affecting sharply the aromatic profile of fresh grapes and even improving it in withered grapes.

Since the end of the last century, many works have been carried out to verify the effect of controlled oxygen intake on the chemical and organoleptic characteristics of red wines. In spite of the large number of studies on this subject, oxygen remains a cutting-edge research topic in oenology. Oxygen consumption leads to complex and not univocal changes in wine composition, sometimes positive such as color stabilization, softening of mouthfeel, increase of aroma complexity. However, the variability of these effects, which depend both on the oxygenation conditions and the composition of the wine, require more efforts in this research field to effectively manage wine oxygen exposure. The present study is focused on the evolution of the chemical composition of four different Nebbiolo wines, each of them added with 4 different doses of oxygen (7, 14, 21, and 28 mg/L total intake) during the first month of storage. In this perspective, the evolution over time of wine color and polyphenols was studied. Acetaldehyde, glyceraldehyde and glyoxylic acid were quantified by HPLC. These compounds can play a role in wine aging creating condensed colored and stable products involving anthocyanins with or without tannins. Moreover, some volatile aldehydes correlated with oxidized olfactory notes, including methional and (E)-2-alkenals, have been quantified by GC-MS. Overall, during storage a decrease of color intensity, total and free anthocyanins and an increase in polymeric pigments (in particular the contribution to the red color of pigments not-bleachable by SO2 or dTAT%) and some minor aldehydes was observed. Nevertheless, the differences in color parameters between the samples with different doses of oxygen were modest. These evidences were in contrast with an evident and detectable increase of free acetaldehyde content at increasing doses of oxygen measured after 60 days of storage. The effect of oxygen on color and production of SO2 non-bleachable pigments during aging varies with wine composition, with Nebbiolo wines appearing not very reactive in this respect, probably due to their low content in anthocyanins and high content in tannins.

We analyzed the relation between the assessment of grape berry skin thickness by means of histology sections and instrumental mechanical properties measurements. Berry skin of Vitis vinifera L. cultivar Corvina vineyards from Valpolicella Valpantena zone (Verona, Italy) were tested, evidencing a strong correlation between the two thickness determination methods. The middle or equatorial berry skin portion was found to be the less variable in instrumental skin thickness determination. In addition, unlike other studies, no correlation between the skin thickness and cell layers number was found.

Plant proteins have been proposed as an alternative to animal-origin proteins in the wine industry because they are allergen-free and vegan-friendly. The aim of this study was to evaluate the effectiveness of plant proteins as fining agents on red wines with different phenolic composition. Two formulations for commercially available vegetal proteins (potato and pea origin) were assessed at two doses to modulate the fining treatment to the wine phenolic profile. The results evidenced that fining agents derived from plants have different levels of effectiveness on the removal of phenolic compounds depending on the origin, the formulation used, dose applied, and also wine characteristics. On Nebbiolo wine, the study was particularly significant due to its phenolic composition. One pea-based fining agent had an effect comparable to gelatin (animal origin) on the removal of polymeric flavanols with a minor loss of anthocyanins and therefore better preserving the wine color in terms of intensity and hue. For Primitivo, Montepulciano, and Syrah wines, even though there was a formulation-dependent effect, vegetal proteins gave more balanced reductions in terms of target phenolic compounds contributing to astringency and color perception.

Aims: Fourier Transform-Near Infrared (FT-NIR) spectrum and instrumental texture parameters were assessed as total phenol content and extractability predictors in intact grape seeds. Methods and results:The study was carried out on Cabernet-Sauvignon seeds from grapes harvested at six different advanced physiological stages throughout ripening and calibrated by flotation to reduce the in-field heterogeneity inside each sample. Among the instrumental mechanical properties tested (i. e., break force, break energy, Young’s modulus of elasticity and deformation index), the seed Young’s modulus of elasticity showed an increase during the first four weeks of ripening. This parameter also showed significant correlations with phenol content and extractability, although with low R coefficients. These correlations highlighted that the springier seed tissues greatly increase phenol extractability. Nevertheless, the best prediction of seed phenol content, performed directly on intact seeds, was found using FT-NIR spectroscopy in transmittance mode. The standard error of prediction for total phenol content was less than 8 %, while that for phenol extractability was worse. Conclusion: On the basis of these results, the two analytical methods could be applied in oenology for the rapid monitoring of seed phenolic maturity. Significance and impact of the study: The phenolic composition of grapes at the harvest time is a key factor determining their quality, and thus the quality of the finished wine. The chemical methods used for the determination of seed phenol content and extractability are generally slow because they require a preliminary extraction. Therefore, a rapid evaluation of these parameters could be highly interesting for the oenological sector.

Aims: Phenolic compounds, extractable from grape skins and seeds, have a notable influence on the quality of red wines. Therefore, in this work the phenolic composition of 13 red grape cultivars, grown in one of the most traditional Spanish vine zones, was studied in order to identify significant varietal differences. Methods and results: Anthocyanin concentration and profile, total proanthocyanidin and flavanol contents in berry skins and seeds were determined by spectrophotometric and HPLC methods. The highest concentrations of total anthocyanins was found in the Loureira Tinta, Sousón and Ferrol varieties, while Ferrol was rich in proanthocyanidins in berry skin and Caíño Bravo was rich in proanthocyanidins and flavanols in berry seeds. Malvidin-3-monoglucoside was usually the major anthocyanin. Nevertheless, the anthocyanin profile was characterized mainly of di-substituted molecules for Albarello, Brancellao and Caíño da Terra grapes. Ferrol, Loureira Tinta and Sousón grapes showed the highest values of primitive anthocyanins (delphinidin and petunidin derivatives). Conclusion: Many differences in the phenolic composition of the cultivars studied were found. The results of the phenolic characterization can be utilized in winery in order to apply the most appropriate maceration and winemaking techniques to the processed grapes. Significance and impact of study: Knowledge of the biodiversity of the grape varieties of Galicia (North-West Spain) is still scarce. This study, on phenolic composition, provides oenological information that can be useful to improve the quality of the wines produced.

Aims: This study was designed to gain knowledge of three Controlled Denomination of Origin (DOC) Italian sweet white Passito wines (Caluso Passito DOC, Cinque Terre Sciacchetrà DOC and Passito di Pantelleria DOC) produced in several areas of Italy from grapes dried with different systems and vinification techniques. Methods and results: Physico-chemical and chromatic characteristics, sodium, potassium, gluconic acid, glucono-γ-lactone, acetaldehyde, sorbitol, laccase, organic acids and semi-quantitative free volatile profile were determined on these wines. Caluso Passito DOC wines presented higher contents of organic acids (above all, malic acid), main metabolites from noble Botrytis cinerea (laccase, glycerol, gluconic acid and benzaldehyde) and low contents of total polyphenols. Among the volatile components, normal fatty acid ethyl esters (ethyl hexanoate and ethyl octanoate), branched-chain esters (ethyl 2-methylpropanoate, ethyl 2-methylbutyrate, ethyl 3-methylbutyrate) and benzaldeyde characterized this Passito wine. Cinque Terre Sciacchetrà DOC wines showed the lowest total acidity with a lower amount of malic acid and a higher content of polyphenols. This wine was characterized by some predominant acetates (isoamyl acetate), alcohols, benzaldehyde and an isoprenoid, Β-damascenone. Passito di Pantelleria DOC wines presented higher amounts of ashes resulting in higher pH values compared to the other two Passito typologies. Due to its production from aromatic grapes, it showed several varietal components such as terpenes, while ethyl esters/acetates and alcohols were less represented. Conclusion: This survey provides information allowing the characterisation of three Passito dessert wines at high commercial value. Significance and impact of the study: This study provides oenological information to be utilised to protect and valorise the Controlled Denomination of Origin sweet wine production and contributes to the preservation of traditional and terroir productions and their commercialization.

Aims: The aim of this work was to evaluate the kinetics of anthocyanin extraction in berries of cv Brachetto and Nebbiolo, having the same level of total soluble solids, but with different skin hardness. Methods and results: A puncture test was carried out on berries calibrated according to their density, estimated by flotation in different salt solutions. For each variety, two groups of berries of different skin hardness were selected: soft (< medium value) and hard (> medium value). Spectrophotometric and HPLC methods were used to evaluate the kinetics of anthocyanin extraction in a hydroalcoholic buffer solution. In each of the examined cultivars, the grapes with a higher break skin force produced extracts with a higher content in total anthocyanin. The anthocyanin profile of extracts of Brachetto hard skin is characterized by a higher content of acetyl-glucosides. Conclusion: Texture analysis, which is fast and inexpensive, turned out to be an excellent analytical technique to verify skin hardness measurements. The break skin force proved to be a mechanical parameter able to estimate the extractability of anthocyanins with adequate reliability. Significance and impact of study: The possibility of having an easy way to determine maturity index able to estimate the extractability of phenol compounds with sufficient reliability, can be a valuable tool for the enological community.

Aims: The aim of this work was to study the color of the wine grapes using the CIELAB parameters and to develop colorimetric indexes which can be used as a rapid method to assess the anthocyanin content of the wine grapes in the vineyard. Methods and results: L*, a*, b* parameters were measured by a reflectance spectrophotometer on eighteen red winegrapes at harvest. Two indexes were calculated: CIRG2, used as colorimetric index for table grapes and CIRWG (Color Index for Red Wine Grapes). These indexes showed effective potentialities for descriptive, taxonomic and ampelografic studies. Particularly the CIRWG index is more correlated to the total anthocyanin amount, while the CIRG2 is more correlated to the different forms of the anthocyanins. Conclusion: The colorimetric indexes applied directly in the vineyard permit to assess the total anthocyanin content and to give further quickly information on grape quality and maturity. Significance and impact of study: The development of analytical methods for the evaluation of anthocyanin immediates, easily applicable, at low cost in the field by grape-growers and winemakers, can be very useful in deciding the harvest date.