BACKGROUND:Italy harbors one of the richest grapevine biodiversities worldwide, yet the sensory identity of wines from many native cultivars remains poorly defined despite their relevance on the market at regional, national, or international levels. This study provides a systematic sensory characterization of 18 Italian monovarietal white wines, analyzed across 246 commercial samples, including wines never investigated before by sensory analysis. Analysis of variance, hierarchical cluster analysis, and principal component analysis were applied to Rate-All-That-Apply (RATA) data performed by trained panelists to define a lexicon and identify the sensory attributes characterizing and discriminating the 18 wine types. RESULTS:A statistically based lexicon comprising 29 olfactory and seven taste/mouthfeel descriptors was defined. Multivariate statistics showed that the 18 monovarietal wine types belong to four main olfactory dimensions, labeled as fruity-balsamic, thiolic-mineral, floral-sweet, and toasty-dried. A three-dimensional space was defined along the four olfactory directions. Müller Thurgau, Gewürztraminer, Albana, and Falanghina emerged as the most representative wines in these directions, outlining the vertices of a spatial framework within and around which the other wines are distributed. Sensory wheels representing structured visual synthesis of the most relevant attributes (odor, taste, mouthfeel) were developed as 'identity models', providing systematic tools for defining wines' varietal typicality. CONCLUSION:Results are relevant for enologists and wine sellers as standardized reference sensory models for production and communication, as benchmarks for PDO/PGI quality control and disciplinary improvement, for researchers to advance modeling of wine sensory quality through sensometabolomic wine studies. Results also support the international recognition and valorization of Italian grapevine biodiversity according to Agenda 2030 sustainable development goals. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Since 2005, mannoproteins (MPs) have been authorised by the European Community (EU, regulation 2165/2005) as an additive for tartaric and protein stabilisation. However, their effect on colour stabilisation in red wine is still a matter for debate in research due to the nature of the product, timing, dose, and wine variety. In recent years, the International Organisation of Vine and Wine (OIV) expert working group has been carrying out collaborative work to elucidate the role of MPs in red wine. The aim of the present work is to show the results of the third year of a study in which five laboratories performed the same analyses on the same wines. Three mannoproteins (A, B, C) at two concentrations (20–40 g/hL) were added to two wines (French and Italian). The equilibration period was one week at cellar temperature (15–18 °C). The wines were then analysed at two aging time points: after one month and five months. The analyses consisted of a cold stability test, CIEL*a*b* coordinates, colour parameters (Abs 420–520–620 nm), and a copigmentation index. An analysis of individual anthocyanins and the characterisation of the MPs was also carried out. Results were expressed as the means of four repetitions carried out in five laboratories. Besides slight variations in colorant intensity and CIEL*a*b* coordinates, none of the wines showed differences visible to the human eye. MPs seem to prevent the loss or degradation of molecular anthocyanins at one month aging. The copigmentation index seemed to increase depending mainly on MP typology, with no difference between the two tested doses, indicating that the 20 g/hL concentration may be appropriate for these wines. The stability of the colouring matter was always observed after the MP treatment. However, the multivariate analyses revealed that after five months of aging the MP-C was the most effective for both wines. Finally, the effect on stability of the colouring matter is MP-dependent, the mannose content (>80 %) and molecular weight (37 < kDa < 79) being the critical factors for the effectiveness of MPs in red wine colour stability.

Enzymatic browning has deleterious implications in food industry. In musts, especially in white ones, this phenomenon driven by polyphenol oxidases threatens wine quality and stability. Herein, an oleanolic acid (OA)-enriched extract from Aglianico red grape pomace obtained by the green solvent dimethylcarbonate was investigated as an alternative anti-browning agent. The extract inhibited tyrosinase with an IC₅₀ of 83.84 ± 7.42 μg/mL. When added to Fiano di Avellino musts (0.01-5.0 mg/mL), it reduced browning, as demonstrated by CIELAB colorimetry, with effective stabilization at values ≥0.08 mg/mL. LC-MS/MS analyses highlighted preservation of caftaric acid, catechin, and epicatechin. These data, along with sustained levels of grape reaction product in treated samples, indicated reduced oxidative degradation. Principal component and correlation analyses confirmed a concentration-dependent protective effect against must browning. These findings highlight the potential of OA-enriched extracts as natural, sustainable alternatives to sulphur dioxide for limiting enzymatic browning.

One effect of climate change on grape composition is the increased biosynthesis of quercetin and its glycosides in response to UV-B radiation. High concentrations of quercetin in wine can exceed its solubility threshold, resulting in undesirable precipitation that negatively impacts clarity and consumer perception. This poses a challenge to producers in terms of both quality and economics. Starting from a survey of quercetin instability and its presence in wines, this review summarises the current understanding of the biochemical and physicochemical mechanisms that regulate quercetin stability and precipitation in red wines. It also covers the factors involved in quercetin extraction and stability during vinification and oenological strategies to counteract these effects.Taken together, these findings demonstrate that the stability of quercetin in red wines is governed by a complex interplay of factors, including anthocyanin-mediated copigmentation, pH, temperature, nucleation seeds and the broader phenolic composition of the wine matrix. By elucidating these mechanisms, the review provides a framework for predicting and managing quercetin precipitation, thereby supporting improved wine quality and colloidal stability in the challenging conditions imposed by climate change.

BACKGROUND:Climate change-driven warming is increasing wine ethanol, promoting an atypical convergence between pH and titratable acidity (TA), and favouring the accumulation of specific wine volatiles: γ-nonalactone (γ-C9) and massoia lactone (MLac). This study evaluated how ethanol and acidity modulate release and sensory impact of γ-C9 and MLac in red wine. A deodourised commercial red wine was reconstituted into nine model matrices using a 3 × 3 factorial design (12%/14%/16% v/v ethanol; pH/TA ratios 0.40/0.55/0.80) and spiked with γ-C9 and MLac. Headspace release was quantified by solid-phase micro-extraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and trained assessors performed triangle tests and rate-all-that-apply (RATA) profiling (orthonasal, retronasal, taste/mouthfeel). RESULTS:Orthonasal perception results showed that γ-C9 was discriminated in all low pH/TA matrices, and also MLac was perceivable in high ethanol/low pH/TA matrices. These sensory results were explained by a higher release of the lactones in the headspace of wines with 16% v/v and low pH/TA; however, some sensory differences were not explained by headspace changes, suggesting matrix-dependent perceptual interactions. RATA indicated a shift from citrus/tropical notes towards sweeter/ethereal nuances with greater body as ethanol increased and/or pH/TA rose, while taste ratings showed reduced sourness and increased bitterness at high ethanol/high pH/TA. CONCLUSIONS:Overall, these results suggest that ethanol and acidity act as interactive modulators, influencing volatile organic compounds (VOCs) release, their perceptual integration, and taste balance. In this context, enological practices such as wine acidification, essential to counteract climate-induced imbalances, should be carefully evaluated for their potential ability to enhance the sensory impact of γ-C9 and MLac and overall sensory quality in red wines. © 2026 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Colloids play a crucial role in red wine quality and stability, yet their composition and formation mechanisms remain poorly understood. Recent studies from the D-Wines (Diversity of the Italian Wines) project aimed to elucidate the structure, composition, and formation mechanisms of red wine colloids by analysing monovarietal wines from 10 Italian red grape varieties. Colloid-forming molecules, specifically proteins, polysaccharides, and tannins, were examined in over 100 wines, showing a wide diversity across the samples. Electrophoretic analysis demonstrated that all proteins in the wines exist as high molecular weight aggregates, likely including tannins. Moreover, the wines could be categorised into two groups based on the electrophoretic mobility of the protein aggregates, which appeared to be related to the quantity of protein-reactive tannins in each variety. Asymmetrical Flow-Field Flow Fractionation (AF4) with online multidetection was used to isolate and characterise red wine colloids in their native state, revealing diverse colloidal populations across wines. This diversity was attributed to the varying proportions of proteins, polysaccharides, and phenolics present in the colloidal particles. These latter were coloured, indicating the presence of red pigments in the colloids. A correlation analysis of the compositional data of the wines and their colloidal particles indicated that the association of proteins with polymeric pigments should be important for red wine colour. Overall, the findings led to the proposal of an updated model for colloidal particles in red wines, suggesting that the process for their formation occurs through the assembly of protein-tannin sub-aggregates, followed by their interaction with polysaccharides. The compactness of these colloidal particles has been linked to the wine’s protein content, with colloidal particles containing higher protein levels being less compact. These findings suggest that proteins likely play a role in determining the structure and properties of red wine colloidal particles. Moreover, this study provides an updated framework for understanding how compositional differences among grape varieties, particularly the content of protein-reactive tannins, shape colloidal structures, ultimately impacting key wine quality parameters such as colloidal stability and colour.

Quercetin Q, a phenolic compound released from grape skins during red wine maceration, has been identified as a source of instability in bottled wines, particularly Sangiovese, due to its crystallisation. This phenomenon represents an economic challenge for producers and affects the clarity of wine and consumer perception. Recent studies have shown that anthocyanins, probably due to co-pigmentation, increase the solubility of Q, thereby reducing the risk of crystallisation. Based on these results, this study aimed to validate these findings in real red wines and to better understand the factors influencing the risk of Q precipitation. Thirty-two monovarietal Italian red wines from the same harvest, which differed significantly in phenolic composition, were analysed focusing on the quantification of Q-glycosides (Q-Gs) and aglycones in the wine bulk and the sediment when present at different time points. In 30 out of 32 wines, hydrolysis of Q-Gs occurred during the first year of ageing, but only in 2/3 of the wines analysed, Q remained soluble in solution. The remaining wines behaved like saturated solutions as Q was detected in insoluble precipitate: however, even after aging, no clear precipitation threshold could be determined. Partial least squares (PLS) regression showed that the most influential risk categories for Q precipitation were pH and the monomeric anthocyanin/flavanol ratio. In addition, the Pearson correlation analysis demonstrated that not only anthocyanins but also tannins help to make Q more soluble. Our results contribute to a deeper understanding of the factors influencing quercetin stability in red wines, with implications for producers seeking to mitigate precipitation risks.

BACKGROUND:As environmental awareness grows, interest in sustainable agriculture is increasing. A promising alternative is the use of plant-beneficial microorganisms such as Trichoderma spp., which suppress pathogens, promote growth and enhance productivity. In viticulture, Trichoderma species have been studied mainly for pathogen control, but their impact on wine composition and quality remains underexplored. The present study evaluates the effects of Trichoderma afroharzianum T22 and its metabolite, 6-pentyl-α-pyrone (6PP) on Vitis vinifera cv. Aglianico over 2 years. Biometric parameters (grape yield per vine, 100-berry weight), basic chemical parameters (soluble solids, pH, titratable acidity) and polyphenols (anthocyanins, high-molecular-weight tannins, vanillin-reactive flavans) were analyzed in grapes. The resulting wines were assessed for phenolic composition and sensory attributes. RESULTS:Treatments increased anthocyanin content in both grapes and wine, at the same time as reducing low-molecular-weight tannins in grape skins, potentially decreasing bitterness. Despite an increase in high-molecular-weight tannins, no significant differences in astringency perception were detected. The wines from treated vines showed enhanced odor complexity, with stronger floral, tobacco and black pepper notes, likely a result of the increased terpenic volatile compounds. The effect of T. Afroharzianum T22 spores was more pronounced than that of 6PP. CONCLUSION:This study highlights the potential of Trichoderma-based treatments as eco-friendly alternatives to synthetic chemicals in viticulture. Beyond disease control, Trichoderma spp. and their metabolites may positively influence grape composition and wine quality, contributing to a more sustainable viticultural model. Further research is needed to better understand their effects on grapevine physiology and metabolism. © 2025 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Intensive use of copper-based pesticides in agriculture can impact human health and biodiversity: the accumulation of this metal in soil negatively affects crop yields. There is growing interest in developing new tools that are capable of monitoring copper occurrence in agricultural contexts through the use of quick and user-friendly approaches for non-specialists, e.g., farmers. This work focuses on the development of a glove-based electrochemical sensor, enhanced with gold nanoparticles, for the detection of copper ions on leaves. The developed device proved was capable of detecting copper ions contained in a copper-based pesticide commonly used in agriculture (Cupravit Bio Advanced). The on-glove analytical device was characterized using garden leaf as the model system and subsequently applied to on-site detection of copper ions on vine leaf treated with Cupravit Bio Advanced. The procedure was very facile: sampling was carried out by touching the leaf with the strip and the stripping-voltammetric measurement was performed by adding a few microliters of an acidic solution to the strip. The on-glove approach allowed evaluation of the level of copper-based pesticide used, avoiding complex and time-consuming tasks. Such operation opens up a wide range of possibilities for improving precision agriculture and sustainable development at the point-of-need for the use of non-specialists.

Copper (II), a vital fungicide in organic viticulture, also acts as a wine oxidation catalyst. However, limited data are currently available on the impact that maximum allowed copper (II) ion doses in wine grapes at harvest can have on aged wine quality. This was the focus of the present study. We investigated the copper (II) effects by producing both white and red wines from musts containing three initial metal concentrations according to the limits set for organic farming. In detail, the influence of copper (II) on fermentation evolution, chromatic characteristics, and phenolic compounds was evaluated. Interestingly, the white wine obtained with the highest permitted copper (II) dose initially exceeded the concentration of 1.0 mg/L at fermentation completion. However, after one year of storage, the copper (II) content fell below 0.2 ± 0.01 mg/L. Conversely, red wines showed copper (II) levels below 1.0 mg/L at the end of fermentation, but the initial copper (II) level in musts significantly affected total native anthocyanins, color intensity, hue, and acetaldehyde concentration. After 12-month aging, significant differences were observed in polymeric pigments, thus suggesting a potential long-term effect of copper (II) on red wine color stability.

BACKGROUND:Postharvest dehydration affects the metabolism of grapes, impacting odorous secondary metabolites and therefore the features of the corresponding passito wines - high-quality products with winemaking practices linked to specific territories and related autochthonous grape varieties. Water loss and temperature conditions are the main variables of the dehydration process. This study assessed how they impacted the patterns of free and glycosylated volatile organic compounds (VOCs) of the exocarp (pulp) and epicarp (skin) in Nebbiolo and Aleatico, a neutral and semi-aromatic red grape variety, respectively. Dehydration parameters were set in tunnel conditions, and VOCs were quantitatively analyzed by solid phase extraction-gas chromatography-mass spectrometry. RESULTS:For Nebbiolo grapes, weight loss had a greater impact on free volatiles than dehydration temperature, with a 20% weight loss increasing total VOCs in both exocarp and epicarp. Low temperature (10 °C) significantly increased (P < 0.05) the glycosylated VOCs' terpene content. In Aleatico grapes, weight loss was key in modulating free volatiles, with 30% weight loss and 15 °C leading to significant increases in VOCs, especially exocarp terpenes, acids and benzenoids. More stressful dehydration (30% weight loss at 25 °C) resulted in higher aroma precursor concentrations. CONCLUSION:These findings can assist passito wine production in preserving varietal aromas of original grapes trough optimized dehydration conditions, preventing sensory homologation occurring because of strong uncontrolled dehydration. They can also promote optimization of energy consumption, thus fostering financial and environmental sustainability. © 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.

Red wine colloids, crucial in determining wine quality and stability, are understudied due to inadequate techniques for studying them effectively in the natural wine environment. Recently, Asymmetrical Flow Field-flow Fractionation (AF4) with online multidetection has emerged as a novel analytical tool for quantifying, fractionating, and characterizing red wine colloids in their native state. This study aimed to characterize the colloidal composition of 24 monovarietal Italian wines produced without filtration, oak contact, fining treatments, malolactic fermentation, macerating enzymes or ageing on yeast lees. AF4 analysis allowed quantification and characterization of wine colloids based on light scattering signal (MALS; gyration radius - Rg), size (hydrodynamic radius - Rh) and absorbance (A280 & A520 nm). The results showed that each wine contained up to five distinct colloids' populations, varying in size and gyration radii. Despite possessing very similar Rh, most colloids exhibited great differences in compactness, as indicated by their varying Rg values. Comparing the A280 signal of whole wines to those of wines containing only species larger than 5 kDa (considered colloids) allowed to calculate the percentage of molecules involved in colloidal particles assembly, ranging from 1 to 44 % of the total A280 absorbing compounds, reflecting the diversity among wines. The A520 signal indicated the presence of polymeric pigments in the colloidal fraction. Notably, colored colloids all had Rg > 20 nm, indicating their association with other colloidal-forming compounds. This observation led to the conclusion that, apart from free anthocyanins and polymeric pigments, the color of red wines is also due to colloidal particles formed by the latter bound to proteins, with their quantity being highly variable across wines of different origin. These findings, which highlight the fundamental role of proteins in shaping the colloidal status of red wines, were utilized to propose an updated hypothetical model for colloidal aggregation in red wine.

The cheese wine pairing is a beloved combination subject to a certain subjectivity due to sensorial, psychological, chemical, and cultural factors. This work represents a first attempt to explore the in vitro interactions between cheese, wine, and saliva to objectively measure the pairing. Two experimental red wines obtained from the same grape cultivar and four different cheeses were studied for their composition. Binding reactions between wine and cheese were carried out in three simulated tasting trials and, after precipitation, the wine phenolic content, Saliva Precipitation Index (SPI), and total proteins were evaluated. The optimal pairing (OP) was calculated considering the decrease in salivary and cheese proteins by wine, defined as the cleansing effect; the decrease in astringency due to the cheese, measured by the SPI, and the coating fat which would remain in mouth after eating a piece of cheese. Based on obtained results, the semi-hard cheese was identified as the best pairing option for the two experimental red wines. The differences in the phenolic content between the two wines were instead not enough to show a significant influence on the OP. The in vitro cheese wine pairing can contribute to understanding of wine tasting but it is only a part of the puzzle. However, this first contribution paves the way for additional studies on the molecular and chemical interactions involved in aroma and textural perception in simulated trials.

The polyphenol extraction and evolution during a traditional 14-day fermentation of the Aglianico red grape, a variety widely cultivated across Southern Italy, was for the first time investigated, with the purpose of optimizing the phenolic profile in finished wines. Anthocyanins, BSA-reactive tannins, iron-reactive phenols, and vanillin-reactive flavans (VRFs) were analyzed in the free-run must, pressed pomace liquid, and in pomace extracts at different maceration times. Experimental evidence suggested that, instead of the typical 14-day maceration of Aglianico grapes, it is recommendable to choose an 11-day maceration in order to prevent the over-extraction of polyphenols that may detrimentally affect the sensory characteristics of wines. In fact, Aglianico wines, if not properly produced, can be affected by excessive astringency due to its high tannin contents. The findings of the present study can provide insightful knowledge to all the winemakers dealing with grape varieties characterized by high quantities of tannins. Also, an earlier racking would supply grape pomaces extremely rich in valuable phenolic compounds to be extracted and reused in several industrial segments in the frame of circular bioeconomy.

Background: Climate changes have been leading to an excessive synthesis of quercetin (Q) and its glycosides (Q-Gs) in specific red grape varieties, such as Sangiovese. This has resulted in concentrations overcoming the solubility threshold of Q in wines, with the consequent formation of undesirable precipitates. This study aims at assessing the impact of various factors, including anthocyanins, temperature, nucleation seeds and time, on the precipitation of Q in red wine. Results: The influence of anthocyanins on Q solubility was examined by adding a grape skin extract rich in anthocyanins to a model solution containing 89 mu mol L-1 of Q. The data revealed that the solubility of both Q and Q-Gs increased as a function of the anthocyanin concentration in the model solution. In a subsequent experiment, red wines were stored at two different temperatures (2 and 20 degrees C), supplemented with Q nucleation seeds, and monitored over a 10-day period. Notably, after only 3 days of contact with Q seeds at 2 degrees C, a reduction of over 75% in Q concentration was observed in the supernatant. Among the considered factors, contact with nucleation seeds emerged as the most significant one (P < 0.0001). Conclusion: Q precipitation in red wines is influenced by the presence of anthocyanins in solution, although it is not the sole determinant. The data also suggested that a potential strategy for wineries to mitigate the risk of Q precipitation in bottled wine would be the acceleration of this process by promoting the formation of nucleation seeds. (c) 2024 Society of Chemical Industry.

BACKGROUND:Four red wine matrices representing different red wine styles with the same VOCs (volatile organic compounds), were obtained by enriching a bleed wine with increasing amounts of deodorized dry extract obtained from the pressed wine of the same vinification. The release of VOCs was determined by solid phase micro-extraction-gas chromatography-mass spectrometry (SPME-GC-MS), in conditions mimicking those applied during sensory assessments. RESULTS:Results show that even though the perception of the overall odor intensity was not significantly influenced by the matrix, this latter modulated the odor profiles: at rising wine dry extract, fruity, floral odors decreased, while dehydrated fruit, woody-toasty, vegetal-earthy notes increased. These changes cannot be fully explained by the observed significant influence of the matrix on the release of VOCs or by their correlations with the considered matrix components (ethanol, residual sugars, phenolics, pH), but findings suggest that perceptual interactions are involved. CONCLUSION:This study could be useful in pressing and blending management for wine aroma quality also considering wine compositional trends under the current climate change context. © 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.

Some oligopeptides can impart kokumi flavor to foods and beverages, a topic still not addressed in wine. A targeted ultra-high performance liquid-chromatography-mass spectrometry (UHPLC-MS/MS) metabolomics method capable of quantifying both amino acids and oligopeptides in wines was therefore developed and validated, confirming the presence of 50 oligopeptides in wine, most of which had been previously unexplored. In silico screening of the affinity of these oligopeptides to interact with CaSR, the protein necessary to activate kokumi sensations, highlighted 8 dipeptides and 3 tripeptides as putative kokumi compounds. These compounds were ubiquitous in a representative set of Trentodoc classic method sparkling wines, with an average concentration of kokumi oligopeptides of 19.8 mg/L, ranging between 9.1 and 33.3 mg/L. Half of the sparkling wine samples also contained glutamic acid at concentrations equal to or greater than the threshold for the umami taste in wine, namely, 48 mg/L. Sensory tests on the dipeptide Gly-Val confirmed the ability of this novel kokumi compound to significantly modify the perception of complex real wine matrices but not of the simple model one. Preliminary laboratory-scale fermentation tests showed that the oligopeptide profile in wines is linked to the starting grape matrix and that the patterns change by fermenting barley or apple juice with the same yeast.

Leaf removal is a cultural practice mainly aimed at improving cluster zone microclimates and impacting primary and secondary metabolites, such as volatiles. This research aimed to assess the impact of defoliation on free and glycosylated aromas of a neutral (‘Nebbiolo’) and a semi-aromatic (‘Aleatico’) red variety. Defoliation was performed at fruit set (BBCH 71) and, for ‘Nebbiolo’, also at berries touch (BBCH 81) phenological stages. Skins and pulps were separately analyzed by Solid Phase Extraction–Gas Chromatography/Mass Spectrometry. Results showed that the response to defoliation was variety-dependent. For ‘Nebbiolo’, especially when performed at the berries’ touch stage, defoliation had a significant effect on the accumulation of free volatiles and glycosidic precursors. Differently, free and bound ‘Aleatico’ volatiles were less impacted by defoliation. Interestingly, in both grapevine varieties, defoliation significantly enhanced the accumulation of aroma precursors in grapes’ skins, which is of particular relevance for red wine production and their aging potential. Moreover, results could be helpful for the management of grape quality, as defoliation is currently considered as a strategy to address climate change issues.

Minor grape varieties often possess key traits to produce wines with specific territorial identity. Italy is home to a wide selection of autochthonous grapevines. In 2005, four white grape varieties from the Amalfi coast, Fenile, Ginestra, Pepella and Ripoli were registered in the National Catalogue grapevines. They are all complementary varieties with a rich biodiversity and linked to an ancient wine heritage. Studies on such varieties have not been conducted yet. Here, the metabolite content of the above four grape varieties is described. Ripoli was the richest in quercetin derivatives while very low was the content of kaempferol derivatives; Pepella possessed an equal amount of quercetins and kaempferols; Ginestra and Fenile featured a quercetins abundance twice that of kaempferols. Also, the (+)-catechin content was higher than (–)-epicatechin's; B-type procyanidins occurred in higher concentrations in Pepella and Ripoli than in Fenile and Ginestra. Hydroxycinnamic acids were also identified and quantified. Seeds from each variety were carefully analyzed and flavanols were identified up to decamers along with their galloylation percentage. The obtained data are a tool of variety differentiation and useful to develop appropriate vinification procedures to ameliorate the quality of wines.

A strategy aimed at decreasing the content of quercetin (Q) and quercetin glycosides (QG) was applied to prevent future quercetin precipitation in wines. Different oenological fining agents were tested: polyvinylpolypyrrolidone (PVPP), a vegetable protein (VP), four yeast lysate (YLs) and a polyfunctional product (MIX) obtained by mixing PVPP, vegetable protein and a yeast lysate selected among the four tested. For each fining agent the adsorption isotherms were obtained; based on Freundlich model, PVPP and MIX showed the best adsorption of Q and QG. The MIX determined also a contemporary lower adsorption of other phenolic compounds. The treatment carried out with MIX on the Sangiovese wines determined a decrease of Q (from −27 to −47% with respect to the initial values) and of QG (−17%) preserving wine anthocyanins.