Mass Spectrometry-Based Proteomic Profiling of a Silvaner White Wine.

The comprehensive identification of the proteome content from a white wine (cv. Silvaner) is described here for the first time. The wine protein composition isolated from a representative wine sample (250 L) was identified via mass spectrometry (MS)-based proteomics following in-solution and in-gel digestion methods after being submitted to size exclusion chromatographic (SEC) fractionation to gain a comprehensive insight into proteins that survive the vinification processes. In total, we identified 154 characterized (with described functional information) or so far uncharacterized proteins, mainly from Vitis vinifera L. and Saccharomyces cerevisiae. With the complementarity of the two-step purification, the digestion techniques and the high-resolution (HR)-MS analyses provided a high-score identification of proteins from low to high abundance. These proteins can be valuable for future authentication of wines by tracing proteins derived from a specific cultivar or winemaking process. The proteomics approach presented herein may also be generally helpful to understand which proteins are important for the organoleptic properties and stability of wines.

Malolactic fermentation of lactic acid bacteria isolated from southern Brazilian red wine.

The objective was to isolate lactic acid bacteria (LAB) from southern Brazil's wines and investigate their potential as starter cultures for malolactic fermentation (MLF) in Merlot (ME) and Cabernet Sauvignon (CS) wines through the fermentative capacity. The LAB were isolated from CS, ME, and Pinot Noir (PN) wines in the 2016 and 2017 harvests and evaluated for morphological (color and shape of the colonies), genetic, fermentative (increase in pH, acidity reduction, preservation of anthocyanins, decarboxylation of L-malic acid, yield of L-lactic acid, and content of reduced sugars), and sensory characteristics. Four strains were identified as Oenococcus oeni [CS(16)3B1, ME(16)1A1, ME(17)26, and PN(17)65], one as Lactiplantibacillus plantarum [PN(17)75], and one as Paucilactobacillus suebicus [CS(17)5]. Isolates were evaluated in the MLF and compared to a commercial strain (O. oeni), as well as a control (without inoculation and spontaneous MLF), and standard (without MLF). CS(16)3B1 and ME(17)26 isolates finished the MLF for CS and ME wines, respectively, after 35 days, similar to the commercial strain, and CS(17)5 and ME(16)1A1 isolates ended the MLF in 45 days. In the sensory analysis, ME wines with isolated strains received better scores for flavor and overall quality than the control. Compared to the commercial strain, CS(16)3B1 isolate obtained the highest scores for buttery flavor and taste persistence. CS(17)5 isolate received the higher scores for a fruity flavor and overall quality and the lowest for a buttery flavor. The native LAB displayed MLF potential, regardless of the year and grape species from which they were isolated.

Quantifying the grapevine xylem embolism resistance spectrum to identify varieties and regions at risk in a future dry climate.

Maintaining wine production under global warming partly relies on optimizing the choice of plant material for a given viticultural region and developing drought-resistant cultivars. However, progress in these directions is hampered by the lack of understanding of differences in drought resistance among Vitis genotypes. We investigated patterns of xylem embolism vulnerability within and among 30 Vitis species and sub-species (varieties) from different locations and climates, and assessed the risk of drought vulnerability in 329 viticultural regions worldwide. Within a variety, vulnerability to embolism decreased during summer. Among varieties, we have found wide variations in drought resistance of the vascular system in grapevines. This is particularly the case within Vitis vinifera, with varieties distributed across four clusters of embolism vulnerability. Ugni blanc and Chardonnay featured among the most vulnerable, while Pinot noir, Merlot and Cabernet Sauvignon ranked among the most resistant. Regions possibly at greater risk of being vulnerable to drought, such as Poitou-Charentes, France and Marlborough, New Zealand, do not necessarily have arid climates, but rather bear a significant proportion of vulnerable varieties. We demonstrate that grapevine varieties may not respond equally to warmer and drier conditions, and highlight that hydraulic traits are key to improve viticulture suitability under climate change.

[Pasteur and the entry of wine into scientific modernity]. / Pasteur et l'entrée du vin dans la modernité scientifique.

Among the imposing bulk of Louis Pasteur's work, his Studies on Wine are the least known and commented. However, in these Studies, collected in 1874, he displayed all the facets of his versatile genius, as a citizen, as a teacher, and as a scientist. As a chemist, he analysed the steps of vinification and the mechanisms of fermentation. As a citizen, he aimed at the improvement of an industry key to the French prosperity. He was also a man rooted in his terroir; aware of the know-how of wine makers, and a teacher working hard with his students. This article explores the circumstances and results of his work and assesses the so-called pasteurization of wine, that, contrary to the epic narrative, was not later established for wine, as it was for other natural beverages. Lastly, the article raises the question of the role of the Studies on Wine on the emergence of the Pasteurian microbian theory of human illnesses.

Title: Pasteur et l'entrée du vin dans la modernité scientifique. Abstract: Dans l'œuvre de Louis Pasteur, les travaux sur le vin sont peut-être les moins étudiés. Pasteur y révèle pourtant ses différentes facettes. Chimiste décidé à élucider les mécanismes de la fermentation alcoolique, il a en tête l'amélioration de la production et de la qualité des vins destinés à l'exportation. Il est aussi un homme de terroir gardant un lien avec le savoir-faire des vignerons et une tradition empirique de dégustation, et un enseignant dévoué à ses étudiants. Cet article explore l'impact des méthodes pasteuriennes sur l'amélioration et la conservation des crus, et l'avenir de la pasteurisation. Il s'interroge pour finir sur le rôle des études sur le vin dans l'élaboration de la théorie microbienne des maladies humaines.

Identification of Oak-Barrel and Stainless Steel Tanks with Oak Chips Aged Wines in Ningxia Based on Three-Dimensional Fluorescence Spectroscopy Combined with Chemometrics.

With the increased incidence of wine fraud, a fast and reliable method for wine certification has become a necessary prerequisite for the vigorous development of the global wine industry. In this study, a classification strategy based on three-dimensional fluorescence spectroscopy combined with chemometrics was proposed for oak-barrel and stainless steel tanks with oak chips aged wines. Principal component analysis (PCA), partial least squares analysis (PLS-DA), and Fisher discriminant analysis (FDA) were used to distinguish and evaluate the data matrix of the three-dimensional fluorescence spectra of wines. The results showed that FDA was superior to PCA and PLS-DA in classifying oak-barrel and stainless steel tanks with oak chips aged wines. As a general conclusion, three-dimensional fluorescence spectroscopy can provide valuable fingerprint information for the identification of oak-barrel and stainless steel tanks with oak chips aged wines, while the study will provide some theoretical references and standards for the quality control and quality assessment of oak-barrel aged wines.

A novel solution to tartrate instability in white wines.

Tartrate stabilization remains a necessary step in commercial wine production to avoid the precipitation of crystals in bottled wine. The conventional refrigeration method to prevent crystallization of potassium bitartrate is time-consuming, energy-intensive, and involves a filtration step to remove the sediment. Nevertheless, it is still the most used stabilization method by winemakers. This work exploits for the first time an alternative to traditional cold stabilization that explores the potential of carefully tailored surface coatings obtained by plasma polymerization. Coatings containing amine functional groups were most potent in binding and removing potassium in heat-unstable wines. In contrast, carboxyl acid groups rich surfaces had the most significant impact on heat-stabilized wines. The results of this study demonstrate that surfaces with carefully designed chemical functionalities can remove tartaric acid from wine and induce cold stabilization. This process can operate at higher temperatures, reducing the need for cooling facilities, saving energy, and improving cost-effectiveness.

The Impact of Fermentation Temperature and Cap Management on Selected Volatile Compounds and Temporal Sensory Characteristics of Grenache Wines from the Central Coast of California.

Grenache wines from the Central Coast of California were subjected to different alcoholic fermentation temperature regimes (Cold, Cold/Hot, Hot) and cap management protocols, namely, punch down (PD), or no punch down (No PD), to determine the effect of these practices on the color, aroma, and the retronasal and mouthfeel sensory characteristics of the resulting wines. Descriptive analysis (n = 8, line scale rating 0-15) results indicated that the combination of a hot fermentation temperature and no punch downs led to a significantly higher intensity in perceived color saturation (7.89) and purple hue (8.62). A two-way analysis of variance (ANOVA) showed that cap management was significantly more impactful on the perception of orthonasal aromas than fermentation temperature. The reduction aroma was significantly higher in No PD wines (5.02) compared to PD wines (3.50), while rose and hot aromas had significantly higher intensity perception for PD wines (5.18, 6.80) than for No PD wines (6.80, 6.14). Conversely, analysis of selected volatile compounds indicated that fermentation temperature was more impactful than cap management regime. Cold/Hot wines had higher concentrations of important esters such as ethyl hexanoate (650 µg/L) and isoamyl acetate (992 µg/L). Cold wines had a higher concentration of ß-damascenone (0.719 µg/L). TCATA evaluation (n = 8) indicated that Cold/Hot PD wines had a significantly higher citation proportion of fruit flavor (1.0) and velvet astringency perception (0.80) without significant reduction flavors. Finally, the present study represents a contribution with the main volatile compounds (e.g., ß-damascenone and esters in the Cold and Cold/Hot fermented wines, respectively; hexanol in PD wines, which may be potentially responsible for a hot mouthfeel), and sensory characteristics (red fruit, tropical fruit, white pepper, and rose) of Grenache wines grown in the Mediterranean climate of the Central Coast of California.

Optimization and Validation of a Method to Determine Enolones and Vanillin Derivatives in Wines-Occurrence in Spanish Red Wines and Mistelles.

Understanding the chemical nature of wine aroma demands accurate quantitative determinations of different odor-active compounds. Quantitative determinations of enolones (maltol, furaneol, homofuraneol, and sotolon) and vanillin derivatives (vanillin, methyl vanillate, ethyl vanillate, and acetovanillone) at low concentrations are complicated due to their high polarity. For this reason, this paper presents an improved and automated version for the accurate measure of these common trace wine polar compounds (enolones and vanillin derivatives). As a result, a faster and more user-friendly method with a reduction of organic solvents and resins was developed and validated. The optimization of some stages of the solid phase extraction (SPE) process, such as washing with an aqueous solution containing 1% NaHCO3 at pH 8, led to cleaner extracts and solved interference problems. Due to the polarity of these type of compounds, an optimization of the large volume injection was also carried out. Finally, a programmable temperature vaporization (PTV) quartz glass inlet liner without wool was used. The injector temperature was raised to 300 °C in addition to applying a pressure pulse of 180 kPa for 4 min. Matrix effects were solved by the use of adequate internal standards, such as ethyl maltol and 3',4'-(methylenedioxy)acetophenone. Method figures of merit were highly satisfactory: good linearity (r2 > 0.98), precision (relative standard deviation, RSD < 10%), high recovery (RSD > 89%), and low detection limits (<0.7 µg/L). Enolones and vanillin derivatives are associated with wine aging. For this reason, the methodology was successfully applied to the quantification of these compounds in 16 Spanish red wines and 12 mistelles. Odor activity values (OAV) indicate that furaneol should be considered an aroma impact odorant in red wines and mistelles (OAV > 1) while homofuraneol and sotolon could also produce changes in their aroma perceptions (0.1 < OAV < 1).

Comparison of phenolic composition and sensory quality among pear beverages made using Saccharomyces cerevisiae and Torulaspora delbrueckii.

The effects of Saccharomyces cerevisiae and Torulaspora delbrueckii on phenolic composition and sensory quality were characterized in the production of alcoholic beverages from selected pear cultivars with diverse biochemical characteristics. The fermentation process generally affected the phenolic composition by increasing the contents of hydroxycinnamic acids and flavan-3-ols and reducing the levels of hydroxybenzoic acids, procyanidins, and flavonols. Although the phenolic compositions and sensory properties of pear beverages depended primarily on pear cultivar selection, the applied yeast strains also played important roles in beverage quality. Fermentation with T. delbrueckii resulted in higher caffeoylquinic acid and quercetin-3-O-glucoside contents, higher rated intensities of 'cooked pear' and 'floral' odors and a sweeter taste than fermentation with S. cerevisiae. Moreover, higher concentrations of hydroxybenzoic acids, hydroxycinnamic acids, and flavonols correlated closely with astringency perception. Applying T. delbrueckii strains and breeding novel pear cultivars are important approaches to produce fermented beverages of high quality.

Red Wine High-Molecular-Weight Polyphenolic Complex Ameliorates High-Fat Diet-Induced Metabolic Dysregulation and Perturbation in Gut Microbiota in Mice.

Red wine polyphenolic complexes have attracted increasing attention as potential modulators of human metabolic disease risk. Our previous study discovered that red wine high-molecular-weight polymeric polyphenolic complexes (HPPCs) could inhibit key metabolic syndrome-associated enzymes and favorably modulate human gut microbiota (GM) in simulated colonic fermentation assay in vitro. In this work, the efficacy of HPPC supplementation (150 and 300 mg/kg/day, respectively) against high-fat diet (HFD)-induced metabolic disturbance in mice was investigated. HPPCs effectively attenuated HFD-induced obesity, insulin resistance, and lipid and glucose metabolic dysregulation and ameliorated inflammatory response and hepatic and colonic damage. It also improved the relative abundance of Bacteroidetes and Firmicutes, consistent with an anti-obesity phenotype. The favorable modulation of GM was further supported by improvement in the profile of fecal short-chain fatty acids. The higher dosage generally had a better performance in these effects than the low dosage. Moreover, serum metabolite profiling and pathway enrichment analysis revealed that HPPCs significantly modulated vitamin B metabolism-associated pathways and identified N-acetylneuraminic acid and 2-methylbutyroylcarnitine as potential biomarkers of the favorable effect on HFD-induced metabolic dysregulation. These findings highlight that dietary supplementation with red wine HPPCs is a promising strategy for the management of weight gain and metabolic dysregulation associated with HFD.

Exploring the ecological characteristics of natural microbial communities along the continuum from grape berries to winemaking.

Under natural conditions, a complex and dynamic microbial ecosystem exists on the grape epidermis, which plays an important role in safeguarding grape health and facilitating the conversion of grapes into wine. However, current viticulture and vinification are flooded with excessive chemical additives and commercial ferments, leading to a reduction in microbial diversity, affecting the ecological balance of the natural microbiota and masking the wine terroir. This experiment comprehensively explored the continuous changes in the natural microbiota from the Ecolly (Vitis vinifera L.) grape epidermis to spontaneous fermentation over two years. The results suggested that microbial community structure and composition were significantly influenced by vintage and growing stage, with fungal genera being more stable than bacterial genera during the growing season. The fungal genera Alternaria, Ascochyta, Gibberella and Dissoconium and the bacterial genera Pantoea, Sediminibacterium, Ralstonia and Sphingomonas were mainly present on the grape epidermis in both years. The natural microbial diversity decreased from grape growth to spontaneous fermentation, and the fermentation environment reshapes the community structure, composition and diversity of the wine microbial consortium. These findings provide insights to promote cultivation and fermentation management strategies, advocate natural terroir attributes for grapes and wines, and promote sustainable development of the wine industry.

Development of a Novel Magnetic-Bead-Based Automated Strategy for Efficient and Low-Cost Sample Preparation for Ochratoxin A Detection Using Mycotoxin-Albumin Interaction.

The mycotoxin ochratoxin A (OTA) is toxic to humans and frequently contaminates wine and beer. Antibodies are essential recognition probes for the detection of OTA. However, they have several drawbacks, such as high costs and difficulty in preparation. In this study, a novel magnetic-bead-based automated strategy for efficient and low-cost OTA sample preparation was developed. Human serum albumin, which is an economical and stable receptor based on the mycotoxin-albumin interaction, was adapted and validated to replace conventional antibodies to capture OTA in the sample. Ultra-performance liquid chromatography-fluorescence detection was used in combination with this preparation method for efficient detection. The effects of different conditions on this method were investigated. The recovery of OTA samples spiked at three different concentrations ranged from 91.2% to 102.1%, and the relative standard deviations (RSDs) were 1.2%-8.2% in wine and beer. For red wine and beer samples, the LODs were 0.37 and 0.15 µg/L, respectively. This reliable method overcomes the drawbacks of conventional methods and offers significant application prospects.

Insights into the Uptake, Distribution, and Metabolism of 3-Isobutyl-2-hydroxypyrazine in Grapevine Using a Stable Isotope Tracer.

Methoxypyrazines (MPs) are potent aroma compounds that have been predominately studied in grape berries but can also be detected in other vine tissues. The synthesis of MPs in berries from hydroxypyrazines by VvOMT3 is well established, but the origin of MPs in vine tissues that have negligible VvOMT3 gene expression is unknown. This research gap was addressed through the application of stable isotope tracer 3-isobutyl-2-hydroxy-[2H2]-pyrazine (d2-IBHP) to the roots of Pinot Meunier L1 microvines and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) quantification of HPs from grapevine tissues following a novel solid-phase extraction method. Four weeks post-application, d2-IBHP and its O-methylated product 3-isobutyl-2-methoxy-[2H2]-pyrazine (d2-IBMP) were present in excised cane, berry, leaf, root, and rachis material. Translocation of d2-IBHP and d2-IBMP was investigated, but results were inconclusive. Nonetheless, knowledge that d2-IBHP, and potentially d2-IBMP, are translocated from roots to other vine organs, including the berries, could provide opportunities for controlling MP accumulation in grapevine tissues pertinent to winemaking.

Aroma characteristics of volatile compounds brought by variations in microbes in winemaking.

Wine is a highly complex mixture of components with different chemical natures. These components largely define wine's appearance, aroma, taste, and mouthfeel properties. Among them, aroma is among the most important indicators of wine's sensory characteristics. The essence of winemaking ecosystem is the process of metabolic activities of diverse microbes including yeasts, lactic acid bacteria, and molds, which result in wines with complicated and diversified aromas. A better understanding of how these microbes affect wine's aroma is a crucial step to producing premium quality wine. This study illustrates existing knowledge on the diversity and classification of wine aroma compounds and their microbial origin. Their contributions to wine characteristics are discussed, as well. Furthermore, we review the relationship between these microbes and wine aroma characteristics. This review broadens the discussion of wine aroma compounds to include more modern microbiological concepts, and it provides relevant background and suggests new directions for future research.

Comparison of physicochemical characteristics, antioxidant and immunomodulatory activities of polysaccharides from wine grapes.

In this study, an efficient ultrasonic-assisted extraction method was used for the extraction and optimization of four wine grape polysaccharides. A three-level, three-factor Box Behnken Design combined with the response surface approach was used to optimize the extraction conditions. Their physicochemical properties, molecular structure, antioxidant activity, immunomodulatory activity and hepatoprotective effects were examined and compared. These findings suggest that the four wine grape polysaccharides share similar basic structural features and monosaccharide composition. Furthermore, four wine grape polysaccharides exhibited antioxidant and immunomodulatory activities in a concentration-dependent manner. Moldova (MD) polysaccharide displayed better antioxidant activity and immunomodulatory ability. Furthermore, MD polysaccharide has a significant therapeutic effect on CCl4-induced rat liver injury by improving the antioxidant defense system and inhibiting oxidative stress, indicating that MD has a hepatoprotective effect. Taken together, the MD wine grape polysaccharide may have potential applications in prevention of liver disease in the functional food and pharmaceutical industries.

A method for the quantitative and reversible trapping of sulfidic gases from headspaces and its application to the study of wine reductive off-odors.

Some relevant food systems release tiny amounts of sulfidic gases, whose measurement is difficult because of their inherent instability. The present paper demonstrates that Cu(I) solutions trap quantitatively and stabilize sulfidic gases. Once trapped, the gases remain stable for weeks at 4 °C and at least 8 days at 75 °C. Trapped gases can be quantitatively released with tris(2-carboxyethyl) phosphine (TCEP) and brine dilution and then determined by GC. Trapping solutions, placed in 20-mL opened vials housed in 100 mL hermetically-sealed flasks containing wine in anoxia, have been used to monitor the release of sulfidic gases by wines, revealing that at 50 °C, up to 400 µg/L of H2S and 58 µg/L of MeSH can be released in 68 days, and 3-5 times more at 75 °C in 28 days. The possibility to differentiate between released and accumulated amounts provides key clues to understanding the fate of sulfidic gases in wine and other food systems.

Development and validation of a multiple headspace solid-phase microextraction method for accurate and precise analysis of the aroma of Tawny and White Port wines.

An accurate and precise Multiple Headspace Solid-Phase Microextraction (MHS-SPME) method was developed and validated for quantifying the volatile composition of White and Tawny Port wines. SPME extraction conditions were optimised using a four-factor three-level Box-Behnken design with three blocks and two replications. Optimal extraction conditions were similar for both Port wines. The method showed good linearity (0.001-50 mg/L), precision (<5%), and detection limits (<1µg/L), well below the olfactory detection threshold. Recoveries higher than 95 % were obtained. Twenty-three aroma compounds were quantified in Tawny and, for the first time, in White Port wines, including five acids, fourteen esters, the most abundant class, and four norisoprenoids, whose levels apparently increased with age. White Port wines had a lower abundance of aroma compounds. Results show that this MHS-SPME method is suitable for analysing volatile composition of White and Tawny Port wines, with reduced costs, manipulation time and eliminating matrix effects.

Detection and prediction of Botrytis cinerea infection levels in wine grapes using volatile analysis.

Infection of grape berries (Vitis vinifera) by the fungus Botrytis cinerea (grey mould) frequently occurs in vineyards, resulting in off-flavours and other odours in wine and potential yield losses. In this study, volatile profiles of four naturally infected grape cultivars, and laboratory-infected grapes were analysed to identify potential markers for B. cinerea infection. Selected volatile organic compounds (VOCs) were highly correlated with two independent measures of B. cinerea infection levels, demonstrating that ergosterol measurements provide accurate quantification of lab-inoculated samples, while B. cinerea antigen detection is more suitable for naturally infected grapes. Excellent predictive models of infection level were confirmed (Q2Y of 0.784-0.959) using selected VOCs. A time course experiment confirmed that selected VOCs 1,5-dimethyltetralin, 1,5-dimethylnaphthalene, phenylethyl alcohol and 3-octanol are good markers for B. cinerea quantification and 2-octen-1-ol could be considered as an early marker of the infection.

Health Effects of Red Wine Consumption: A Narrative Review of an Issue That Still Deserves Debate.

A strong controversy persists regarding the effect of red wine (RW) consumption and health. Guidelines for the prevention of cardiovascular diseases (CVD) and cancers discourage alcohol consumption in any form, but several studies have demonstrated that low RW intake may have positive effects on CVD risk. This review evaluated randomised controlled trials (RCTs), examining the recent literature on the correlations between acute and chronic RW consumption and health. All RCTs published in English on PubMed from 1 January 2000 to 28 February 2023 were evaluated. Ninety-one RCTs were included in this review, seven of which had a duration of more than six months. We assessed the effect of RW on: (1) antioxidant status, (2) cardiovascular function, (3) coagulation pathway and platelet function, (4) endothelial function and arterial stiffness, (5) hypertension, (6) immune function and inflammation status, (7) lipid profile and homocysteine levels, (8) body composition, type 2 diabetes and glucose metabolism, and (9) gut microbiota and the gastrointestinal tract. RW consumption mostly results in improvements in antioxidant status, thrombosis and inflammation markers, lipid profile, and gut microbiota, with conflicting results on hypertension and cardiac function. Notably, beneficial effects were observed on oxidative stress, inflammation, and nephropathy markers, with a modest decrease in CVD risk in five out of seven studies that evaluated the effect of RW consumption. These studies were conducted mainly in patients with type 2 diabetes mellitus, and had a duration between six months and two years. Additional long-term RCTs are needed to confirm these benefits, and assess the potential risks associated with RW consumption.

Beyond S. cerevisiae for winemaking: Fermentation-related trait diversity in the genus Saccharomyces.

Saccharomyces cerevisiae is the yeast of choice for most inoculated wine fermentations worldwide. However, many other yeast species and genera display phenotypes of interest that may help address the environmental and commercial challenges the wine industry has been facing in recent years. This work aimed to provide, for the first time, a systematic phenotyping of all Saccharomyces species under winemaking conditions. For this purpose, we characterized the fermentative and metabolic properties of 92 Saccharomyces strains in synthetic grape must at two different temperatures. The fermentative potential of alternative yeasts was higher than expected, as nearly all strains were able to complete fermentation, in some cases more efficiently than commercial S. cerevisiae strains. Various species showed interesting metabolic traits, such as high glycerol, succinate and odour-active compound production, or low acetic acid production, compared to S. cerevisiae. Altogether, these results reveal that non-cerevisiae Saccharomyces yeasts are especially interesting for wine fermentation, as they may offer advantages over both S. cerevisiae and non-Saccharomyces strains. This study highlights the potential of alternative Saccharomyces species for winemaking, paving the way for further research and, potentially, for their industrial exploitation.