Search Results (424)

During red wine production, managing the pomace cap is key for a successful fermentation, allowing the extraction of phenolics and other metabolites and providing the necessary oxygen for yeast activity. In recent years, automatic cap management systems based on the injection of gases have gained popularity, despite the limited scientific information regarding the outcomes of their use. This trial aimed to evaluate the composition of wine during industrial red wine fermentations using an automatic sequential air injection system (i.e., AirMixing MI^TM). Fourteen lots of Cabernet Sauvignon grapes were fermented using four air injection regimes, where the intensity and daily frequency of air injections were set to either low or high. As expected, the treatment combining high-intensity and high-frequency air injection produced the largest dissolved oxygen peaks reaching up to 1.9 mg L⁻¹ per cycle, compared to 0.1 mg L⁻¹ in the low-intensity and low-frequency treatment. Yet, in all cases, little to no accumulation of oxygen overtime was observed. Regarding phenolics, the highest intensity and frequency of air injections led to the fastest increase in total phenolics, anthocyanins, short polymeric pigments, and tannin concentration, although compositional differences among treatments equilibrate by the end of fermentation. The main differences in phenolic compounds observed during fermentation were mediated by temperature variation among wine tanks. Based on these findings, it is advisable to keep the characterizing kinetics of phenolic extraction and expand the study to the aroma evolution of wines fermented with this technology. Full article

Thermovinification has emerged as a rising alternative method in red wine production, gaining popularity among winemakers. The use of autochthonous yeasts isolated from grapes is also an interesting practice that contributes to the creation of wine with a distinctive regional character. This research investigated how combining thermovinification with autochthonous yeast strains influences the fermentation dynamics of Syrah wine. Six treatments were conducted, combining the use of commercial and two autochthonous yeasts with traditional vinification (7-day maceration) and thermovinification (65 °C for 2 h) processes. Sugars and alcohols were quantified during alcoholic fermentation by high-performance liquid chromatography with refractive index detection. Cell viability and kinetic parameters, such as ethanol formation rate and sugar consumption, were also evaluated. The Syrah wine’s composition was characterized by classical wine analyses (OIV procedures). The results showed that cell viability was unaffected by thermovinification. Thermovinification associated with autochthonous yeasts improved the efficiency of alcoholic fermentation. Thermovinified wines also yielded a higher alcohol content (13.9%). Future studies should investigate how thermovinification associated with autochthonous yeasts affects the metabolomic and flavoromic properties of Syrah wine and product acceptability. Full article

Grape pomace (GP), the main by-product of the wine industry, represents a valuable source of bioactive metabolites with significant potential for valorization in the context of sustainable bioresource management. This study systematically characterizes the fatty acid methyl ester (FAME) profile, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities (DPPH, ABTS, ORAC) of GP derived from seven grape varieties across three consecutive vintages (2022–2024). White GP, particularly Verdelho and Sercial, exhibited a superior lipid quality with high concentrations of methyl linoleate (up to 1997 mg/100 g DW) and methyl oleate (up to 1294 mg/100 g DW), low atherogenic (AI < 0.05) and thrombogenic indices (TI ≤ 0.13), and elevated PUFA/SFA ratios (≥8.2). In contrast, red GP, especially from Complexa and Tinta Negra, demonstrated the highest antioxidant potential, with TPC values up to 6687 mgGAE/100 g DW, TFC up to 4624 mgQE/100 g DW, and antioxidant activities reaching 5399 mgTE/100 g (DPPH) and 7219 mgTE/100 g (ABTS). Multivariate statistical analyses (PCA, PLS-DA, HCA) revealed distinct varietal and vintage-dependent clustering and identified key discriminant fatty acids, including linolenic acid (C18:3), lauric acid (C12:0), and arachidic acid (C20:0). These findings underscore the compositional diversity and functional potential of GP, reinforcing its suitability for applications in functional foods, nutraceuticals, and cosmetics, in alignment with circular economy principles. Full article

Anthocyanins are important phenolic compounds in grape skins, affecting the color, oxidation resistance, and aging ability of red wine. In recent years, global warming has had a negative effect on anthocyanin biosynthesis in grape berries. Ethylene serves as a crucial phytohormone regulating the development and ripening processes of fruit; however, the specific molecular mechanism and the regulatory network between ethylene signaling and the anthocyanin biosynthesis pathway remain incompletely understood. In this study, 400 mg/L ethephon (ETH) solution was sprayed onto the surface of grape berries at the lag phase (EL-34), and the changes in anthocyanin-related genes and metabolites were explored through transcriptomic and metabolomic analysis. The results showed that ETH treatment increased Brix and pH in mature berries. In total, 35 individual anthocyanins were detected, in which 21 individual anthocyanins were enhanced by ETH treatment. However, the anthocyanin profile was not affected by exogenous ethylene. Transcriptomics analysis showed that there were a total of 825 and 1399 differentially expressed genes (DEGs) 12 h and 24 h after treatment. Moreover, key structural genes in the anthocyanin synthesis pathway were strongly induced, including VvPAL, VvCHS, VvF3H, VvF3′5′H, VvDFR and VvUFGT. At the maturity stage (EL-38), the expression levels of these genes were still higher in EHT-treated berries than in the control. ETH treatment also influenced the expression of genes related to hormone biosynthesis and signal transduction. The ethylene biosynthesis gene (VvACO), ethylene receptor genes (VvETR2, VvERS1 and VvEIN4), ABA biosynthesis gene (VvNCED2), and ABA receptor gene (VvPYL4) were up-regulated by ETH treatment, while the auxin biosynthesis gene (VvTAA3) and seven genes of the auxin-responsive protein were inhibited by exogenous ethylene. Meanwhile, ETH treatment promoted the expression of the sugar transporter gene (VvEDL16) and two sucrose synthase genes (VvSUS2 and VvSUS6). In EHT-treated berries, 19 MYB and 23 ERF genes were expressed differently compared with the control (p < 0.05). This study provides the theoretical foundation and technical support for the regulation of anthocyanin synthesis in non-climacteric fruit. Full article

As compared to red wine technology, where pomace is macerated, the grape juices and musts are obtained by pressing the grapes and removing the pomace, thus removing an important source of antioxidant molecules. The objective of this study was to exploit the bioactive compounds from the black grape pomace and obtain a new food product, namely pasteurized red must with improved health-promoting properties. The study was conducted on four grape varieties for red wines—Fetească Neagră, Cabernet Sauvignon, Blauer Zweigelt, and Arcaș—each coming from a certain recognized Romanian vineyard, as follows: Murfatlar, Dealu Mare, Ștefănești-Argeș, and Iași, respectively. Both the must and the pomace extract used for each product were from the same variety and region. The recovery of polyphenols was achieved by macerating the pomace at ambient temperature, using solutions of ethanol in concentrations of 25%, 50%, and 75%. The results showed that the most efficient method of polyphenol recovery was obtained by using the ethanolic solution of 50%, which was selected for the subsequent stages of the study. The selected hydroalcoholic extract was concentrated by eliminating the solvent by roto evaporation and used as a source of supplementary bioactive compounds for the pasteurized must. The phenolic profiles of the musts enriched with phenolic extracts were determined by liquid chromatography, UHPLS-HRMS, revealing significant increases in the content of individual phenolic acids and other polyphenols. The phenolic extract recovered from the pomace significantly optimized the phenolic quality of the pasteurized must, thus contributing to the improvement of its nutritional value. The new product has a phenolic profile close to that of a red wine, but does not contain alcohol. Also, this technology is a sustainable method to convert grape waste into a safe, antioxidant-rich grape juice with potential health benefits. Full article

The oxidative degradation of anthocyanins in red wine was investigated under controlled conditions using hydroxyl radicals generated in the presence of Cu (II) as a catalyst. A full factorial experimental design with 23 replicates was used to evaluate the effects of hydrogen peroxide concentration, catalyst dosage, and reaction temperature on anthocyanin degradation over a fixed time. Statistical analysis (ANOVA and multiple regression) showed that all three variables and the main interactions significantly affected anthocyanin loss, with temperature identified as the most influential factor. The combined effects were described by a first-order polynomial model. The activation energies for degradation ranged from 56.62 kJ/mol (cyanidin-3-O-glucoside) to 40.58 kJ/mol (peonidin-3-O-glucoside acetate). Increasing the temperature from 30 °C to 40 °C accelerated the degradation kinetics, almost doubled the rate constants and shortened the half-life of the pigments. At 40 °C, the half-lives ranged from 62.3 min to 154.0 min, depending on the anthocyanin structure. These results contribute to a deeper understanding of the stability of anthocyanins in red wine under oxidative stress and provide insights into the chemical behavior of derived pigments. The results are of practical importance for both oenology and viticulture and support efforts to improve the color stability of wine and extend the shelf life of grape-based products. Full article

The identification of melatonin in grapes has led to the publication of numerous studies on melatonin in wines, and the aim of this study was to perform a systematic review and meta-analysis of published data on melatonin concentrations in wines. In this context, international databases such as Scopus, Web of Science and PubMed were searched for relevant articles (437) up to 29 March 2025. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used. A total of 15 studies from eight countries, involving various wine types and analytical methods, were included in the meta-analysis. Considerable analytical variation was observed across studies, and high-performance liquid chromatography (HPLC) coupled with either mass spectrometry (MS) or fluorescence (FL) detection was shown to be the most accurate and sensitive method for quantifying melatonin. The highest concentrations were found in Spanish red Tempranillo wine, Romanian white Noah wine, and Romanian rosé Lidia wine. Red wines, particularly those produced from Cabernet Sauvignon (CS) grapes, were the most frequently studied. The results of this work provide a clearer picture of melatonin levels in wine. Further research is needed to explore the implications of melatonin content in wine for human health and the wine industry. Full article

Wine organic acids influence their overall quality. This study examines the variability of major acids (tartaric, malic, lactic, citric, acetic, and gluconic) and minor phenolic acids (gallic, protocatechuic, syringic, caftaric, caffeic, cutaric, coumaric, and 2-S-glutathionylcaftaric) in varietal red wines produced from predominantly autochthonous grape cultivars of the Canary Islands. Two hundred and five monovarietal red wine samples were analyzed to assess how the organic acid profiles differed depending on the grape cultivars employed in their production, island of provenance, denomination of origin, and aging, supporting relationships between both genetic and environmental factors. High-performance liquid chromatography and enzymatic methods were used for determining minor and major organic acids, respectively. Many significant differences between grape cultivars, geographical origin, and aging were observed, reflecting the complexity of the composition of the organic acids in red wine and its relationship with viticultural factors. Linear discriminant analysis achieved classification accuracies up to 88.3% by cultivar and 83.4% by island. Correlation and multivariate analyses helped identify compositional patterns and key discriminant acids. This study advances the comprehension of major and minor acid composition and equilibria in red wines and may support future research on quality parameters and regional typicity. Full article

Color, aroma, and overall sensory quality in red wines are largely influenced by oxygen availability during fermentation. This study evaluated the effects of micro-oxygenation under hyperbaric conditions on the physicochemical, chromatic, volatile, and sensory properties of Vitis vinifera L. cv. Monastrell grape must. Grape clusters were manually harvested and fermented under controlled conditions, applying micro-oxygenation treatments at two fermentation stages (day 3 and day 13) within a hyperbaric chamber. Physicochemical analyses, CIELab color measurements, visible reflectance spectra, GC-FID volatile profiling, and descriptive sensory analysis were performed. Micro-oxygenated samples (M1_MOX and M2_MOX) showed significant increases in lightness (L*), redness (a*), chroma (C*), and reflectance in the 520–620 nm range, indicating enhanced extraction and stabilization of phenolic pigments. Volatile analysis revealed that these samples also contained higher concentrations of key esters and terpenes associated with fruity and floral notes. Sensory evaluation confirmed these findings, with MOX-treated wines displaying greater aromatic intensity, flavor persistence, and varietal character. Control samples (M1_CON and M2_CON) exhibited lower color saturation and volatile compound content, along with diminished sensory quality. These results suggest that hyperbaric micro-oxygenation is an effective strategy for improving color intensity and aromatic complexity during red wine fermentation under controlled, non-thermal conditions. Full article

Wine jelly is regarded as a delicacy in many countries and is commonly utilized in grande cuisine. Recently, its popularity has increased among consumers due to its dietary properties and the presence of health-promoting compounds such as antioxidants. Its natural origin and the ability to reflect local traditions and consumer preferences further enhance its appeal. This study aimed to compare the compositional and sensory characteristics of wine jellies prepared using three different gelling agents and four aromatic grape varieties, with the goal of preserving varietal aroma in the final products. White wines from Pálava and Moravian Muscat and red wines from Agni and Rosa were used. The selected gelling agents were agar, vegan gelatin, and traditional gelatin. Basic analytical parameters were assessed in both the wines and the resulting jellies. Sensory evaluation was conducted by trained panelists, assessing consistency, appearance (clarity), taste, and bouquet. Confectionery-grade jelly from red wines demonstrated the best consistency, while gelatin jellies from white wines showed superior clarity. Due to a preference for sweeter flavors, jellies from red wines were favored across all variants. The strongest varietal bouquet was observed in Moravian Muscat samples, irrespective of the gelling agent used. The optimal choice of gelling agent depends on the target quality attributes. Gelatin is preferred for firmness and clarity, while vegan gelatin is ideal for preserving aroma and achieving a balanced sensory profile. Full article

Resveratrol is a natural polyphenol found in grapes, berries, and red wine, commonly studied for its biological activity. In vitro research often uses high concentrations of resveratrol applied for short incubation times. However, resveratrol reaches relatively low concentrations in vivo when it is used as a dietary supplement. Therefore, the aim of this study was to investigate the cellular response of cardiomyocytes to low, physiologically relevant concentrations of resveratrol and, in particular, to compare these responses depending on the duration of exposure. Cardiomyocytes were treated with resveratrol for either 1 day, 1 week, or 1 month. Functional assays assessing metabolic activity, cell cycle distribution, and apoptosis intensity were performed, along with analysis of selected pathways at protein levels. The results showed that the cellular response differed markedly depending on the duration of resveratrol treatment. Observed changes indicated alterations in energy metabolism and effects consistent with anti-aging activity. Full article

Large-scale commercial wine fermentation requires the monitoring and control of multiple variables to achieve optimal results. Challenges in measurement arise from turbidity, stratification in large unmixed volumes, the presence of grape skins and solids during red wine fermentations, the small changes in variables that necessitate precise sensors, and the unique composition of each juice, which makes every fermentation distinct. These complications contribute to nonlinear and time-variant characteristics for most control variables. This paper reviews sensors, particularly online ones, utilized in commercial winemaking. It examines the measurement of solution properties (density, weight, volume, osmotic pressure, dielectric constant, and refractive index), sugar consumption, ethanol and glycerol production, redox potential, cell mass, and cell viability during wine fermentation and their relevance as variables that could enhance the estimation of parameters in diagnostic and predictive wine fermentation models. Various methods are compared based on sensitivity, availability of sensor systems, and their appropriateness for measuring properties in large commercial wine fermentations. Additionally, factors influencing the adoption of control strategies are discussed. Finally, potential opportunities for control strategies and challenges for future sensor developments are outlined. Full article

Reusing agro-industrial by-products is a successful strategy that aligns with the 2030 Sustainable Development Goals. Red grape pomace poses a significant environmental challenge, particularly for wine-producing nations. Due to its high moisture content and seasonal availability, ensiling emerges as a potential method to prolong the nutritional value of red grape pomace, supporting the need for research into its application in animal nutrition. This study analyzed the bale ensiling process for red grape pomace by assessing its potential integration into ruminant diets and comparing its storage stability to untreated preservation methods. Baled silage units (approximately 300 kg each) were employed for this purpose. Analytical evaluations were conducted at 0, 7, 14, 35, 60, and 180 days of storage to monitor microbial and fermentation activity, nutritional composition, and bioactive attributes. Bale silage preserved the nutritional and microbial quality of red grape pomace for ruminant feed over a storage period of 180 days. The results demonstrated that bale silage successfully maintained the macro-composition, bioactive compounds, and antioxidant properties while reducing the fatty acid profile’s susceptibility to oxidation. By contrast, untreated storage led to significant spoilage. We concluded that bale ensiling is a suitable and effective technique that preserves red grapes for ruminant feed over a long period. Full article

While cold chain transportation facilitates the utilization of wine grapes grown in remote mountainous areas, there is currently a lack of research on the impacts of different post-harvest temperatures on the quality of wine grapes. Therefore, three temperatures—room temperature (20 °C), chilled (4 °C), and frozen (−20 °C)—were selected to study the effects of post-harvest low-temperature treatments. The results indicated that the contents of tartaric acid and total polyphenols in the resulting wines were higher after the grapes underwent freezing, while the opposite trend was observed for those stored at room temperature. The changes in color lightness of wines were inversely correlated with the changes in color saturation and red chromaticity, while the yellow chromaticity of wines fermented after storage exhibited a slight increase. Rutin and ferulic acid were identified as the characteristic monophenols that decreased post-storage, and heptanal emerged as the volatile compound that decreased similarly. Furthermore, the tannin contents of the resulting wines demonstrated a strong correlation with temperature: when grapes were chilled, they reached the highest level, presenting a decreasing trend over time. For low-temperature storage, 1-hexanol, ethyl caprylate, isopentyl acetate, and (Z)-2-heptenal were identified as characteristic volatile compounds under the different treatments. Overall, the choice of an appropriate chilling temperature for the post-harvest storage of grapes can ensure the quality characteristics of the produced wine. This study confirms the potential value of cold chain transportation for the effective utilization of wine grapes grown in remote areas. Full article

Resveratrol is a naturally occurring phytoalexin found in red grapes, cocoa berries, and red grape wine. This compound exhibits potent antioxidant, anti-inflammatory, and anticancer properties. However, its clinical application is significantly hindered by poor aqueous solubility and rapid degradation at physiological pH, resulting in extremely low systemic bioavailability. This review explores three key aspects: green extraction methods for the efficient and sustainable isolation of resveratrol; structure–activity relationship studies of resveratrol derivatives to identify compounds with improved bioavailability and therapeutic efficacy; and advanced drug delivery systems to enhance resveratrol solubility, stability, and achieve targeted tissue delivery. All of these solutions collectively aim to increase resveratrol bioavailability, enabling the development of effective pharmaceutical formulations and maximizing the clinical potential of this promising compound. The aim of this review is to summarize the key studies published in the last five years, highlighting innovative advancements in sustainable extraction, structural modifications, and delivery strategies for resveratrol. Full article