Search Results (78)

This study evaluates the partial dealcoholization of red wine using reverse osmosis (ACM3) and nanofiltration (TS80) membranes at 25 and 35 bar, targeting 2% and 4% ethanol reductions. Membrane performance was assessed through fouling analysis and ethanol partitioning, while wine phenolic (flavan-3-ols, anthocyanins) and color characteristics (CIELab parameters) were determined. The 2% reduction process with ACM3 at 25 bar resulted in minimal phenolic changes. The 4% reduction process revealed distinct performance profiles: ACM3 exhibited exceptional stability (3.35–5.30% permeability loss, linear flux decline with R² > 0.93) and ethanol rejection of 17.6–25.5%, while TS80 achieved processing rates three to six times faster with moderate fouling (16.3% loss, 7.7–13.3% rejection). Decreases in flavan-3-ols and anthocyanin concentrations correlated with fouling intensity rather than processing duration. Proanthocyanidin structure remained stable, and color shifts reflected changes in polymeric pigments rather than anthocyanin loss. Reverse osmosis at low transmembrane pressure proved most suitable for quality preservation. The operational trade-off is clear: TS80 offers three to six times faster processing but with greater phenolic loss, while ACM3 requires longer batch times with minimal fouling. Both processes demonstrate that membrane-based dealcoholization without fluid replacement is feasible, providing winemakers with a valuable method to reduce alcohol while preserving quality. Full article

Grape pomace is a major byproduct of winemaking and a rich source of bioactive anthocyanins with potential functional value. This study aimed to optimize anthocyanin extraction from Tannat grape pomace and evaluate its antioxidant and anti-aging activities. Ultrasonic-assisted extraction combined with a Box–Behnken design identified optimal conditions of 51.27 °C, 53.46% ethanol, 20.10 min ultrasonication, and a 1:24.05 solid-to-liquid ratio, yielding 186.21 ± 1.03 mg/100 g (R² = 0.9798, p < 0.0001). Tannat Grape Pomace Anthocyanins showed strong antioxidant capacity, with 2,2-Diphenyl-1-picrylhydrazyl scavenging of 89.44% ± 0.87% at 0.2 mg/mL (IC₅₀ = 0.09 mg/mL) and 2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging of 95.83% ± 0.54% at 0.75 mg/mL (IC₅₀ = 0.26 mg/mL). In Caenorhabditis elegans, TGPA extended lifespan, improved motility, and increased heat and oxidative stress resistance without reducing reproductive capacity. Lifespan is a key indicator of aging. This study holds significant implications for advancing our understanding of the mechanisms underlying lifespan regulation, the connection between aging and disease, as well as the development of anti-aging therapies for humans. In conclusion, these findings indicate that Tannat Grape Pomace Anthocyanins possess promising antioxidant and anti-aging potential and support the sustainable, high-value utilization of grape pomace. This approach directly aligns with the core principles of sustainable agriculture by transforming an agricultural byproduct into a valuable resource. Full article

Natural wines represent a new trend in winemaking without the use of preservatives and starter cultures, revealing the unique quality traits of grapes, wine, and terroir, but are susceptible to spoilage or undesirable fermentations. This study investigated the microbial populations associated with organic grapes, must, and natural wines of the Limniona red grape variety, focusing on different production stages and fermentation vessels. Samples included immature and ripe grapes, initial and fermenting must, filtered and unfiltered wines, and final bottled and filtered wines. These were analyzed in order to enumerate key groups of microorganisms and identify beneficial yeasts and bacteria of alcoholic and malolactic fermentation, respectively, as well as potential markers of off-flavors. Culture-dependent methods were used to enumerate yeasts and bacteria, while Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) and 16S rRNA sequencing provided taxonomic resolution. Beneficial fermentation microorganisms (especially Saccharomyces yeasts) were scarce in initial grapes, where other contaminants or wild yeasts were present. Gradually, as fermentation progressed, there was a prevalence of Saccharomyces cerevisiae strains of increased diversity in matured wine, as well as several lactic acid bacteria (LAB) of malolactic fermentation. Most LAB were identified as Lactobacillus and Oenococcus species. Other bacteria from environmental sources, irrelevant to alcoholic/malolactic fermentation or spoilage, like Burkholderia, were also present during the vinification process. The type of vessel affected the type of LAB that prevail, with an abundance of Oenococcus in clay vessels versus Lactobacillus species in stainless-steel vessels. Notably, Lentilactobacillus parafarraginis can be linked to off-flavors if they represent a high percentage of the wine microbiota. These findings highlight the importance of understanding, monitoring and controlling microbial succession during production stages in order to prevent sensory faults and ensure the stable quality of natural wines. Full article

International standards for wines with Protected Designation of Origin (PDO) require characterisation through both analytical and sensory criteria, although sensory evaluation remains inherently subjective, especially regarding organoleptic properties. This study examined paired Blanc de noir and red wines made from identical grape varieties to determine whether varietal traits remain perceptible regardless of the vinification method while also assessing the role of visual stimuli in influencing olfactory and gustatory perception. Controlled tastings were conducted using both transparent and opaque glassware, with experienced panellists recording sensory descriptors. Physicochemical parameters were measured using a Lyza 5000 analyser to confirm compliance with quality standards, while statistical analyses of sensory data were conducted using the XLSTAT–Basic, student-type user software. Results showed that the absence of visual cues did not mislead tasters in recognising core attributes; however, the winemaking method significantly affected descriptors linked to maceration, including flavour intensity, astringency, and red/dark fruit notes. Panellists distinguished between white and red wines at statistically significant levels, even without visual input, suggesting that vinification-related chemical composition primarily guided their perception. Direct correlations were observed between red winemaking descriptors and parameters such as pH, lactic acid, glycerol, and volatile acidity, while indirect correlations were found with malic acid and titratable acidity. The results highlight how winemaking methods, chemical composition, and sensory perception interact in defining varietal characteristics. Full article

Grape pomace (GP), a polyphenol-rich byproduct of winemaking, holds considerable health benefits and potential as an antibiotic alternative for livestock animals. However, its utilization is compromised by the contamination of mycotoxins produced by pathogenic molds (with ochratoxin A (OTA) being the most frequently detected), which pose hidden health risks to both livestock animals and human beings. This study evaluated the efficacy of thermal–pressure treatment (pressure cooking) with and without the addition of acidic and alkaline agents, and the combined thermal-pressure and fermentation with four lactic acid bacteria (LAB) strains, including Lactobacillus bulgaricus (LB6), Lacticaseibacillus paracasei (previously Lactobacillus paracasei) (BAA-52), Lactobacillus acidophilus, and Lactiplantibacillus plantarum (previously Lactobacillus plantarum), on reducing OTA and preserving polyphenols in GP. The study found that pressure cooking alone reduced OTA by approximately 33–35% in 30–45 min. The addition of citric acid (CA) or acetic acid (AA) enhanced OTA reduction to 46.9–55.2% and 51.7–54%, respectively, while preserving more polyphenols, notably anthocyanins. Conversely, pressure cooking with the addition of NaHCO₃ facilitated greater OTA reductions (40.4–63%), but concomitantly resulted in substantial polyphenol loss, especially anthocyanins. Fermentation for 24 h with LAB following thermal–pressure treatment resulted in up to 97% OTA reduction for Lc. paracasei, L. acidophilus, and Lp. plantarum strains, which displayed similar high effectiveness in OTA reduction in GP. L. bulgaricus (LB6) was least effective (45%), even after 72 h of fermentation. These findings indicate that home-scale pressure cooking combined with lactic acid fermentation effectively detoxifies OTA-contaminated GP, thus enhancing its safety profile for consumption by livestock animals and humans, despite partial polyphenolic losses. Full article

This work focuses on the design of concrete for the construction of winemaking tanks, as well as coating behaviour and stability of the systems in wine immersion. More specifically, alternative laboratory concrete mixtures were investigated by replacing cement with natural pozzolan and using silicate aggregates and quartz sand as filler in order to obtain self-compacting concrete of strength class C 20/25. The optimal mixture was selected and further tests were carried out on the mechanical properties of permeability, durability and thermal conductivity. Three coatings and plain concrete were tested for their leachability of heavy metals in wine. The results show that the selected composition with 20% cement replacement by natural pozzolan has the desired workability and strength and is comparable to a reference concrete without natural pozzolan. The leachability tests show that heavy metals do not leach out upon contact with wine, but only calcium and potassium oxide, which can be easily addressed by coating or treating the surface of the concrete. Also, the optimum coating did not influence the pH of the wine. Full article

Grape stalk (GS) from winemaking is a waste rich in antioxidant compounds that can be valorized to obtain active food packaging materials. Biocomposite films of poly (butylene succinate) (PBS) and poly(3-hydroxybutyrate)-co-hydroxyvalerate (PHBV) with 10% of GS particles, previously submitted or not to subcritical water extraction at 170 °C and 180 °C, were obtained by melt blending and characterized. The fibres were better integrated in the PHBV matrix than in PBS, while other molecular compounds from the fillers were released to the polymer matrix, allowing for their antioxidant action. Fillers promoted the stiffness of PBS films (11–44%), reducing their resistance to break and extensibility by 25%, without significant changes in polymer crystallinity or thermal stability. However, this reduced the crystallinity (13%) and thermal stability of PHBV films, decreasing their rigidity (55%). All fibres promoted the oxygen barrier capacity in composites (by about 20–35% for PBS and PHBV, respectively) while also providing them with UV light blocking effects. This barrier effect enhanced the ability of the films to preserve sunflower oil against oxidation, while in PHBV composites, the migration of antioxidant compounds was also detected. No remarkable differences in the effects of the different GS fillers on the properties of composites were detected. Full article

Winemaking generates significant amounts of byproducts, mainly grape pomace, which is composed of skins, seeds, and stems. Rich in phenolic compounds with antioxidant properties, grape pomace is often underutilized in low-value applications such as compost or animal feed. Recent research highlights its potential as a sustainable alternative to conventional fining agents, such as bentonite, commonly used to improve wine clarity, stability, and sensory attributes. However, previous studies have been limited in scope, focusing on selected wine parameters or narrow experimental conditions. This study explored the use of red and white grape pomace as fining agents for Mavrodaphne red wine, evaluating their effects on anthocyanin level, tannin content, total polyphenol index, chromatic properties, and aromatic profile across varied dosages and contact times. The results indicated that grape pomace, either from red or white grapes, achieved comparable or superior tannin and anthocyanin removal and chromatic enhancement relative to commercial fining agents, without significantly altering aromatic complexity. The findings underscore grape pomace’s suitability as a natural, vegan-friendly, and sustainable fining option, aligning with consumer preferences for cleaner-label wines. This study promotes the adoption of grape pomace in winemaking, supporting waste valorization and advancing sustainable practices within the industry. Full article

An abundant byproduct of the Uruguayan winemaking industry, Tannat grape pomace (TGP), has a unique profile of phenolic compounds, making it a great candidate as an ingredient in the formulation of healthy and sustainable foods. The addition of TGP and sweetener to a muffin formulation may represent a challenge regarding technological properties. In this work, the objective was to develop potential functional muffins with the nutritional claims of “source of/high in fiber” and “no added sugars”, by incorporating TGP as a source of fiber and bioactive compounds and stevia as a sweetener. For this purpose, a factorial experimental design with central points was assessed by varying TGP and sweetener contents. Color was measured in the muffins by a CieLab system, and texture parameters (hardness, elasticity, cohesiveness, gumminess, and chewiness) were obtained by a texture analyzer. The antioxidant capacity was also assessed by total phenol content (TPC by Folin reaction), ABTS, and ORAC-FL methods. Regarding color parameters, the main results showed lower L values for the muffins with higher TGP content (34.4–35.9, p < 0.05). As for texture parameters, lower hardness values (3170–3655 N) were displayed by muffins with higher TGP content (p < 0.05). Elasticity showed no significant differences between the samples (0.773–0.873), with the exception of one of the formulations with higher TGP content. Cohesiveness values ranged between 0.210 and 0.374. Gumminess and chewiness values were lower for the muffin formulation with higher TGP and stevia contents (694 ± 202 N and 538 ± 182 N). Moreover, antioxidant capacity showed increased TPC values for muffins with higher TGP content when compared to the control muffin (without TGP). Similarly, ABTS and ORAC-FL values were higher for the muffins with higher TGP content (15.26–15.59 and 23.92–25.56 µmol Trolox equivalent (TE)/g samples, respectively). In conclusion, TGP muffins represent a sustainable food with adequate technological properties and enhanced nutritional properties, presenting potential to promote health. Full article

The utilization of membrane technologies in winemaking has revolutionized various stages of production, offering precise and efficient alternatives to traditional methods. Membranes, characterized by their selective permeability, play a pivotal role in enhancing wine quality across multiple processes. In clarification, microfiltration and ultrafiltration membranes, such as ceramic or polymeric membranes (e.g., polyethersulfone or PVDF), effectively remove suspended solids and colloids, resulting in a clearer wine without the need for chemical agents. During stabilization, membranes such as nanofiltration and reverse osmosis membranes, often made from polyamide composite materials, enable the selective removal of proteins, polysaccharides, and microorganisms, thereby improving the wine’s stability and extending its shelf life. Additionally, in dealcoholization, membranes like reverse osmosis and pervaporation membranes, typically constructed from polydimethylsiloxane (PDMS) or other specialized polymers, facilitate the selective removal of ethanol while preserving the wine’s flavor and aroma profile, addressing the increasing consumer demand for low-alcohol and alcohol-free wines. This article provides a comprehensive analysis of the advancements and applications of membrane technologies in winemaking. Full article

In winemaking, the use of stems during fermentation is rarely employed due to some undesirable side effects. While the effect of fresh stems on wine is extensively studied, to date limited information is available about the effect of dried stems. This study aimed to investigate the impact of dried stems on the chemical and sensory profile of passito wines. Four withered grape varieties were selected for winemaking: three red and one white from the Verona area. Grapes were fermented with and without withered stems. A major impact on enological parameters, in particular pH and total polyphenols, was observed. In terms of volatile compounds, no release of C₆ alcohols—compounds with undesirable herbaceous odors—was detected. Varietal-dependent release of 3-isobutyl-2-methoxypyrazine (IBMP) was also observed; however in most cases, the content was below the odor threshold. Furthermore, dried stems significantly decreased methanethiol content, likely due to adsorption phenomena. Minor differences were observed in acetate esters, terpenes, and norisoprenoids, though these were not consistent across all wine types. From a sensory point of view, a significant variety-dependent effect was observed, mostly due to IBMP, ethyl acetate, and β-damascenone. Full article

Grape pomace, the solid residue from winemaking, is a rich source of polyphenolic compounds with significant antioxidant properties. However, the efficient extraction of these valuable compounds remains a challenge. This study focuses on optimizing the conditions for the enzyme-assisted extraction of polyphenolic compounds from red grape pomace using cellulase, hemicellulase, and pectinase. The key variables investigated in this study were enzyme concentration, extraction time, and solid/liquid ratio. The results highlight the importance of selecting enzymes based on target compounds, as different enzymes were found to be more effective for specific phenolic fractions. Hemicellulase was most effective for phenolic acids, cellulase for catechins, and pectinase for anthocyanins. Enzyme-assisted extraction significantly increased the yield of phenolic compounds and resulted in higher total phenolic content and antioxidant activity compared to control samples treated with solid/liquid extraction without enzyme addition. These findings confirm that enzyme-assisted extraction is a promising approach for enhancing the recovery of polyphenolic compounds from grape pomace. Full article

Wine lees, the second most significant by-product of winemaking after grape pomace, have received relatively little attention regarding their potential for valorization. Despite their rich content in bioactive components such as β-glucans, industrial utilization faces challenges, particularly due to variability in their composition. This inconsistency impacts the reliability and standardization of final products, limiting broader adoption in industrial applications. β-Glucans are dietary fibers or polysaccharides renowned for their diverse bioactive properties, including immunomodulatory, antioxidant, anti-inflammatory, antitumor, and cholesterol- and glucose-lowering effects. They modulate the immune system by activating Dectin-1 and TLR receptors on immune cells, enhancing phagocytosis, cytokine production, and adaptive immune responses. Their antioxidant activity arises from neutralizing free radicals and reducing oxidative stress, thereby protecting cells and tissues. β-Glucans also exhibit antitumor effects by inhibiting cancer cell growth, inducing apoptosis, and preventing angiogenesis, the formation of new blood vessels essential for tumor development. Additionally, they lower cholesterol and glucose levels by forming a viscous gel in the intestine, which reduces lipid and carbohydrate absorption, improving metabolic health. The biological activity of β-glucans varies with their molecular weight and source, further highlighting their versatility and functional potential. This study investigates how grape variety, vinification technology and extraction methods affect the yield and properties of β-glucans extracted from wine lees. The physico-chemical and mineral composition of different wine lees were analyzed, and two extraction methods of β-glucans from wine lees were tested: acid-base extraction and autolysis. These two methods were also tested under ultrasound-assisted conditions at different frequencies, as well as without the use of ultrasound. The β-glucan yield and properties were evaluated under different conditions. FTIR spectroscopy was used to assess the functional groups and structural characteristics of the β-glucans extracted from the wine lees, helping to confirm their composition and quality. Rheological behavior of the extracted β-glucans was also assessed to understand the impact of extraction method and raw material origin. The findings highlight that vinification technology significantly affects the composition of wine lees, while both the extraction method and yeast origin influence the yield and type of β-glucans obtained. The autolysis method provided higher β-glucan yields (18.95 ± 0.49% to 39.36 ± 0.19%) compared to the acid–base method (3.47 ± 0.66% to 19.76 ± 0.58%). FTIR spectroscopy revealed that the β-glucan extracts contain a variety of glucan and polysaccharide types, with distinct β-glucans (β-1,4, β-1,3, and β-1,6) identified through specific absorption peaks. The rheological behavior of suspensions exhibited pseudoplastic or shear-thinning behavior, where viscosity decreased significantly as shear rate increased. This behavior, observed across all β-glucan extracts, is typical of polymer-containing suspensions. These insights are critical for optimizing β-glucan extraction processes, supporting sustainability efforts and waste valorization in the wine industry. Efficient extraction of β-glucans from natural sources like wine lees offers a promising path toward their industrial application as valuable functional compounds. Full article

By-products generated in the winemaking industry contain compounds with health-promoting properties, which can be reintroduced into the food production chain. This study evaluated the use of a by-product from the industrial processing of grapes as an ingredient in the manufacture of Petit Suisse cheese, made with A2A2 milk and the addition of the probiotic Bifidobacterium animalis subsp. lactis HN019. Two Petit Suisse formulations were made in three independent batches: a control formulation without the addition of the by-product (F0) and a formulation containing 10% of the by-product (F1). The proximate composition of the cheeses was characterized on the first day after manufacturing them. The addition of the by-product led to an increase in ash, lipids, and carbohydrates and a reduction in moisture and protein contents. The physicochemical characterization and the texture profile analysis showed no changes throughout the product’s shelf life. The probiotic counts remained abundant (~eight log CFU/g) in both formulations with no changes seen throughout the shelf life period. Scanning electron microscopy images showed the added bacteria had typical structures. No differences were observed in the fatty acid profiles of the formulations, and both exhibited a total of 18 fatty acids, including saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs). Additionally, the by-product conferred antioxidant activity to the F1 formulation. The addition of the by-product in fresh cheese may be an interesting approach in regards to the processing technology used, its microbiological safety, and its nutritional value. The use of A2A2 milk and a probiotic culture thus enhanced the Petit Suisse cheese, resulting in a healthier product. Full article

The yeast Saccharomyces cerevisiae ensures successful fermentation in winemaking, although the persistent use of commercial strains lead to the loss of aroma complexity of wines. Hence, the research of indigenous S. cerevisiae with proper oenological features and well adapted to specific wine-growing areas become of great interest for winemakers. Here, 206 pure cultures of S. cerevisiae were isolated from two wineries during a two-year sampling campaign and bio-typed through interdelta sequences analyses with the aim to evaluate the occurrence and persistence of the S. cerevisiae wild population linked to each winery. Both wineries belong to the same Verdicchio DOC wine area (Castelli di Jesi), and never used commercial yeasts during fermentation. Results showed 19 different biotypes with a specific population of S. cerevisiae in each winery, without cross-contamination with each other and with commercial starter strains. Moreover, inside each winery a persistence of some dominant biotypes was observed over time (three biotypes in winery 1; 95% of isolates in the two years and one biotype in winery 2; 20% of isolates in the two years), indicating a sort of “winery-effect”. The evaluation of S. cerevisiae populations for the oenological characters by microfermentations showed a proper and well distinct aromatic imprinting on the resulted wines supporting the concept of “winery effect”. Full article