From wine to wine reduction: Sensory and chemical aspects

Different types of red and white wines were prepared by fermentation of the juice which was naturally separated from uncrushed frozen grapes during thawing (A) and from the residual juice by fermentation inside the berries (B). Yeast penetrated the skin of uncrushed grapes and fermented the content completely. The new types of wines were compared with wines prepared conventionally from the whole material of frozen grapes. Chemical and chromatographic analysis (gas chromatography (GC) and solid-phase microextraction-GC/mass spectrometry) showed similar profiles of the aroma volatiles but with significant quantitative differences among the new types of wines, which reflected to the differences observed during the sensory evaluations. The majority of identified compounds were esters, with higher amounts found in (A) wines due to the higher concentration of the must which was separated during thawing. The proposed process is new and of industrial interest for the production of different types of wines from the same raw material in one fermentation batch.

A major concern when shipping wine is whether the condition in which it is received at its destination is the same as when it left the winery. This study explored the effects of shipping conditions on six varietal wines. Four white wines and four red wines were exposed to four different storage conditions to create 32 treatments. Riesling, Gewürztraminer, Sauvignon blanc, and Chardonnay wines were from one producer and of the same vintage. One Merlot and three Cabernet Sauvignon wines were from different labels by the same producer. Storage conditions included 20°C, 40°C, 20/40°C (reflecting diurnal cycle in temperatures), and a sample that traveled in the trunk of a car for three weeks. The 32 wines were evaluated using sensory descriptive analysis. Trained panelists, 11 for white wine and 13 for red wine, rated the wines on 14 and 23 attributes, respectively. Volatiles were analyzed using a HS-SPME-GC-MS analysis. Both sensory and analytical results showed significant differences among the wines stored at the higher temperatures. Differences were noted for a number of compounds, including higher concentrations of vitispirane 1 and 2, TDN, and <i>p</i>-cymene and reductions in several esters and acetates, which are characteristic of aged wines. This is the first study that has assessed sensory changes in wines under conditions that would potentially be experienced by wine in transit.

Background. Wine is one of the oldest traditional alcoholic beverages consumed worldwide. In addition, red and white wines are an excellent source of antioxidant compounds. Numerous studies have focused on the analysis of phenolic acids and flavonoids of several wines originating from organic and conventional cultivars growing grapes. However, to the authors best knowledge, there are no research papers dealing with the phenolic content of wines made on the Ionian Islands so far. Materials and methods. The amount of total phenolics, total flavonoids, total anthocyanins, total tannins, the concentrations of individual phenolic compounds, as well as the antioxidant capacity, were used synergistically to assess the compositional profile of eleven monovarietal wines. Results. As expected, red wines exhibited the strongest antioxidant profile. Vertzami was the richest variety in total phenols and antioxidant capacity, followed by the Avgoustiatis variety and Mavrodaphne variety. Regarding white wines, Thiako white had the highest total phenolic values, while Robola ros contained a similar total phenolic content as the white varieties. A highly positive correlation between the antioxidant capacity and polyphenol composition expressed as total phenolic, total flavonoid, total anthocyanin and total tannin content, was observed. Last, gallic acid and tyrosol were two of the major phenolic compounds detected in all tested wines. Conclusion. Our findings revealed that the amounts of phenolic contents and antioxidant activity vary significantly in different types of wines. The observed differences could be related to a range of variables such as geographical origin, aging, climate and the vinification techniques.

The coffee fermentation process has been established as a determining stage regarding its quality and aroma. The objective of this study was to evaluate the differences that exist between five fermentation processes and within each process (at different fermentation times) based on their volatile and sensory profile. The processes evaluated were dry or natural (NA), semi-dry or honey (HO), and three variations of the wet process, called: conventional aerobic (AC), aerobic with previous fermentation in cherry (AFC) and anaerobic with previous fermentation in cherry (ANFC). The NA process obtained the highest score in the sensory profile and statistically different from the other processes. The volatile profile was determined by headspace solid phase micro-extraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GC-MS). 51 volatile organic compounds (VOCs) were tentatively identified. The main chemical families that allowed differentiating between groups of processes were ketones and pyrroles, and the VOCs that mainly contribute to differentiate between process or groups of processes are: ethanone, 1-(1H-pyrrol-2-yl)-, 2,5-dimethylpyrazine, 2-furanmethanol, 4-vinylguayacol, 2-methylfuran, 2- butanone, 2,3-dimethylpyrazine, acetylpyrazine, 1- (2-furanylmethyl) -1H-pyrrole and 2,2'-bifuran. Within each fermentation process (between treatments) no differences were found from the final score of the sensory analysis, but differences were found from volatile profile. Key words: Volatile profile; time fermentation; GC-MS; SPME.

Copper is one element in wine that has considerable notoriety. While current winemaking practice tends to minimise the amount of copper that results from vineyard and winery sources, the addition of copper(II), either as its sulfate or citrate, to remove sulfidic off-odours may result in an elevated concentration in the finished (bottled) wine. Residual copper in white wine has been linked to oxidative and reductive spoilage processes, although the mechanisms are at times speculative. The presence of copper has been implicated in haze formation (copper casse) and linked to protein instability. More recent concerns include the coexistence of residual copper and hydrogen sulfide in wine stored under low oxygen conditions. The chemistry of copper is important in both white and red wine. While there are some overlapping issues, especially with respect to sulfidic off-odours, both white and red wine display their own unique chemistry. Thus, this review describes the state of knowledge of copper in white wine, differentiating between evidence-based claims and speculation. It also identifies areas of research that will provide a much clearer understanding of the role of copper in wine spoilage.

The influence of partial alcohol reduction in wine on consumer appreciation and acceptability was investigated. Two white wines (Chardonnay and Sauvignon blanc) and two red wines (Merlot and Syrah) were partially dealcoholized using reverse osmosis to span a range of three different alcohol contents (14% to 10%) by grape variety. A group of 79 French wine consumers comparatively rated their appreciation of these wines, first in blind tasting conditions and then with added information. A group of 35 French wine professionals also comparatively rated their appreciation of the same wines in blind conditions and described them by rating the intensity of 10 informal descriptors. Wine professionals did not like the sensory properties of reduced-alcohol wines, whereas consumer likings were less clear and masked a strong segmentation. Experienced wine consumers had similar ratings as the wine professionals and did not like reduced-alcohol wine, whereas less experienced consumers liked the sensory properties of reduced-alcohol wines. Reduced-alcohol wines were described by wine professionals as less hot, sweet, persistent, and balanced than standard wines. Once information about alcohol reduction was given, consumer likings changed and emphasized either the negative or positive effect of information, depending on the consumer. These findings highlight the importance of providing information on the sensory perception and liking of products.

The present paper deals with the characterization of wastewater generated from Greek wineries and wine distilleries. The quantity and the quality of the wastewater of a distillery depends on the type of wine (white or red), on the processes followed for the production of wine as well as on the volume of the tanks that are used. The total production of wastewater from a winery is about 1.2 times greater than the production of wine with BOD5 1740 mg/l and 1970 mg/l for white and red wine respectively, while the corresponding prices for COD are 3112 mg/l and 3997 mg/l and for the total phenolic compounds 280 and 1440 mg/l respectively. From these results, it is expected that the biological treatment of wastewater from white wines will be more efficient than that from red wines. The characteristics from the waste (vinasses) from the distillation of wines and wine lees are also presented.

Winemaking processes and volatile compounds perform an important role in contributing to the quality of wines. ‘Marselan’ is a red grape variety grown in several countries such as France, Brazil and China. This variety has gained international interest in recent years. The volatile profile of Brazilian ‘Marselan’ red wines during various winemaking processes was studied. Four processes were applied: thermovinification, integrale vinification, classic winemaking and classic winemaking pretreated with ultrasound. The wines were characterized with conventional physicochemical analyses, volatile composition and sensory analysis. Sixty-three volatile compounds were identified and semi-quantified. The wines presented different sensory characteristics. The thermovinification and classic winemaking with ultrasound application methods showed a large presence of esters contributing to a fruity and overmaturation aroma in the volatile profile and sensory analysis. An increased presence of vegetal and sulfurous aromas was observed in the wines from the classic winemaking and integrale vinification processes. This effect was most likely attributed to the lower influence of esters which generated a greater perception of other compounds and conferred these aromas. The differences can be directly linked to the various extraction rates in the vinification processes, which result in different interactions between the compounds.

The purpose of the present study was (a) to assess the consumer understanding of aging among different wine types and (b) to check if consumers, using a descriptive questionnaire, recognize the “mellowed dry white wine” conceptual space. A total of 680 worldwide participants, grouped according to their involvement in the wine business, replied to an online questionnaire aiming to understand the white wine aging features and to characterize its sensory descriptors. These descriptors were selected using a Check-All-That-Apply (CATA) approach, concerning wine color, aroma, taste, mouthfeel, and global appreciation. Most consumers (62.8 %) preferred old red to old white wines. Regarding age perception, 50.3 % of the consumers considered old a white wine with 6 to 10 years, while 48.1 % regarded a red wine as old with 11 to 20 years. Nevertheless, 12.2 % believed that a white wine ages better than a red wine. The involvement level did not significantly influence the sensory descriptions of aged dry white wines for the most frequently cited descriptors. Therefore, the generated tasting script was broadly characterized by (a) ‘deep yellow’ to ‘deep gold’ color, (b) aromas of ‘dried fruit’, ‘honey’, ‘caramel’ and ‘oak’, (c) ‘acid taste’, and (d) mouthfeel dominated by ‘body’, ‘length’, ‘viscosity’, ‘smoothness’ and ‘dryness’. Furthermore, global appreciation includes terms such as ‘complex’, ‘persistent’, ‘rich’, ‘concentrated in flavors’, and ‘evolved’. This overall sensory space is consistent with the metaphorical concept of “mellowed by age” wines that seem to be understood by consumers with high and low involvement levels.

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. 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. 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.

SO2 is a preservative often used in the food industry, particularly in the wine industry. However, regulatory authorities and consumers have been strongly suggesting its reduction or even its replacement. In order to understand the impact of SO2 on the profiles of volatile organic compounds (VOCs) as well as amino acids (AAs), the aging of two white wines (one being a varietal and another being a blend) under identical conditions and in the presence of different doses of total SO2 was studied. After alcoholic fermentation (t = 0), either no SO2 was added (0 mg/L), or 30, 60, 90, or 120 mg/L of SO2 was applied. The samples under study were kept on fine lees for 3 months (t = 3). After 3 months (t = 6) and 9 months (t = 12), the wines were bottled and analyzed. For t = 0 and t = 3, the samples were submitted to HS-SPME-GC/MS for VOC analysis and LC-DAD for AA analysis. From the principal component analysis of the detected VOCs, it was observed that the blended wine in comparison with the varietal wine, was less impacted by the applied SO2 doses and aging time. From the AA profile, it was also observed in this study that maturation on fine lees resulted in an increase in the total concentration of AAs as would be expected.

The use of oenological additives is an emerging trend in winemaking aimed at improving technological properties. Recent studies suggest that these additives may also influence aroma persistence after wine consumption by modulating the retention of aroma compounds in the oral cavity. The aim of this study was to evaluate the effect of three commercial oenological additives, hydrolysable tannins (gallotannin and ellagitannin) and yeast mannoproteins, on the oral aroma retention of selected aroma compounds in red and white wines. Eight aromatised wines were prepared, including three red and three white wines with additives and two control wines without additives. Thirty-eight volunteers rinsed with each wine following the Spit-Off Odorant Measurement (SOOM) procedure. Oral aroma retention was calculated by comparing aroma levels in expectorated samples with those in wines prior to oral processing. Results showed that additive type significantly affected oral aroma retention (p < 0.05), depending on both the aroma compound and the wine matrix. In red wines, tannins increased the oral retention of most aroma compounds (5-20%), whereas in white wines, tannins reduced aroma retention. Mannoproteins enhanced oral aroma retention (5-40%) in both wine types. These results highlight the role of interactions between oenological additives, aroma compounds, and the wine matrix in modulating oral aroma retention.

In this study, three kinds of wines separately made from mulberry (MW), grape (GW), or mulberry/grape (MGW) were developed and their enological parameters, sensory scores, volatile components, and microbiota were investigated and compared. Contrary to the order of residual sugar and acidity of the three kinds of wines, the order of alcohol content from high to low is GW, MW, and MGW. A total of 60 volatile components (VCs), including esters (17), alcohols (12), acids (6), aldehydes (7), ketones (3), alkenes (3), amines (3), alkanes (4), pyrazines (2), benzene (1), sulfide (1), and thiazole (1), were identified by gas chromatography-ion mobility spectrometer (GC-IMS). The fingerprint of VCs and principal component analysis revealed that the volatile profiles of MGW and GW were more similar in comparison to that of MW and were significantly correlated with the mass ratio of mulberry to grape. Lactobacillus, Weissella, Pantoea, Leuconostoc, Lactococcus, Paenibacillus, Pediococcus, and Saccharomyces were identified as the main microflora at the genus level shared by the MW, MGW, and GW, suggesting that the heterolactic bacteria may contribute more to the high content of volatile acids in MW and MGW. The heatmap of core microbiota and main VCs of MW, MGW, and GW suggested the complicated and significant correlation between them. The above data implied that the volatile profiles were more closely related to the raw materials of winemaking and markedly affected by the fermentation microorganisms. This study provides references for evaluation and characterization of MGW and MW and improvement of MGW and MW winemaking process. KEY POINTS: • Fruit wine enological parameters, volatile profile, and microbiota were compared. • Sixty volatile compounds were identified by GC-IMS in three types of fruit wines. • Winemaking materials and microbiota affect volatile profiles of the fruit wines.

Several studies have reported a terroir effect on monovarietal wines originating from geographically close areas, using both aromatic and sensory analyses. However, few studies have evaluated this effect on blended wines, a widespread practice that is recognised as adding great complexity to wines. This study aimed to discriminate blended wines produced in five sub-regions of the Corbières AOC according to their aromatic and sensory profiles and across two vintages: 2018 and 2019. The wines’ aromatic profiles were semi-quantified using HS-SPME-GC-MS, and the sensory descriptors enabling the differentiation of the wines were identified by QDA analysis. Although blending is a frequently used process adapted for the production of homogeneous wines within an appellation, the sensory and chemical profiles enabled us to differentiate wines of the Lagrasse and Lézignan sub-regions from those of the Maritime and Durban sub-regions. The variation in intensity of red fruit jam notes may be linked to terroir factors relating to the micro-climatic conditions. Wines from vineyards in coastal regions or at higher elevations were discriminated by lower intensities of this descriptor. However, other discriminating descriptors, such as amyl, earthy or cooked vegetables, could be related to the winemaking process. Correlations were found between the tendencies observed regarding the sensory markers (such as red fruit jam, butter/lactic, amylic, cooked vegetable) and those regarding the chemical families of aroma or specific aroma compounds (such as ethyl esters, higher alcohols and sulphur compounds), whose production is particularly affected by the winemaking processes. Finally, this study shows that it is possible to discriminate blended wines from different geographically close regions, and that the terroir factor with the greatest influence on this discrimination seems to be linked to winemaking processes, including the type of blending carried out.

Apiculate yeasts from Hanseniaspora genus are predominant on the native flora of grapevines, while Hanseniaspora uvarum is well known for its abundant presence in grapes, it results generally, in detrimental quality effects on wine due to high production of acetic acid. By contrast, Hanseniaspora vineae is better adapted to fermentation, increasing flavor complexity in wines as it has been demonstrated in winemaking practices during the last decade. We obtained a collection of more than 22 different Hanseniaspora vineae strains from which we could detect, by a plating screening method, high and moderate protease activity. In this study, we tested these strains under real winemaking conditions on a Sauvignon blanc white wine must. Results obtained demonstrated that there is an interesting protease active diversity in all H. vineae strains when compared to conventional fermentations conducted by Saccharomyces cerevisiae. Four H. vineae strains showed a decrease in wine protein turbidity, up to three times lower than that observed in S. cerevisiae, which imply a significant decrease in the demand for bentonite before bottling. This attribute of some H. vineaestrains should be very attractive at the commercial level to reduce manipulations and flavor removal in the production of delicate white wines such as Sauvignon blanc.