Search Results (27)

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

This study investigates the production of stable ingredients with high bioactive compound content from agri-food wastes. For the valorization process, high-pressure thermal treatment (HPTT) at different temperatures (65, 75, and 85 °C) at 600 MPa for 5 min was applied to three by-products. These HPTTs were compared with conventional thermal treatments (TTs) carried out at the same temperatures and durations. The by-products studied were red pepper (RP) (Capsicum annuum), red wine pomace (RWP) from Tempranillo, and white wine pomace (WWP) from Cayetana, Pardina, and Montúa. Winemaking by-products presented higher fiber content compared to RP (RP 1.94%, RWP 38.14%, and WWP 34.46%). In RP, the color parameters such as lightness (L*) and redness (a*) were not significantly affected by HPTT or TT, and the total phenolic content (TPC), total carotenoid content (TCC), and antioxidant activity (ABTS) remained stable with the HPTT. The RWP and WWP were more sensitive to the HPTT, producing important color changes and reducing the bioactive compounds. Color (especially redness) showed positive correlations with TPC and ABTS, which could serve as a predictive indicator. Our study shows that HPTT can significantly improve the valorization of RP and winemaking by-products like pomace, leading to the production of a stable food ingredient characterized by high bioactive compound content. Full article

The use of agro-industrial by-products in animal feed represents a useful alternative to enhance the sustainability of the agri-food chain. Grape pomace represents an environmental problem mainly for wine-producing countries. Because of the high water content and the seasonality of this feedstuff, ensiling might be a technology to preserve its nutritional quality for a long time, and this must be considered and studied on a commercial scale. This study aimed to characterise the ensiling process of white grape pomace, evaluate its suitability for inclusion in the ruminant diet and compare its shelf life to untreated storage conditions. White grape pomace silos were made with baled silage (300 kg approx.). Samples were analysed at days 0, 7, 14, 35, 60 and 180 of conservation to determine microbial populations, fermentation metabolites, nutritional components and bioactive properties. The collected data were analysed using a general linear model, considering the effect of the treatment, sampling days and their interaction (Proc. GLM, SAS v9.4). White grape pomace showed good suitability for ensiling, and stabilisation was achieved on day 35. The microbial populations and fermentative components observed in silage treatments adhered to the expected standards for high-quality ensiling processes. There were no significant losses of dry matter, and no significant differences were observed in the nutritional composition for ruminant feeding. A small reduction in antioxidant potential was observed and considered irrelevant in terms of the bioactive properties of the silages. Additionally, the cost analysis demonstrated that white grape pomace silage could serve as a more economical feedstuff compared to conventional forages, considering its nutritional value. So, the ensiling of white grape pomace in baled silage is a suitable and cost-effective technique that allows its preservation over a long period. 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

Hypoxia-induced reactive oxygen species (ROS) contribute to neuronal death and play a major role in various neurodegenerative diseases. The use of food by-products with antioxidant and anti-inflammatory properties, such as white wine pomace products (wWPPs), could be valuable not only allows for their revalorization but also for their potential in disease prevention. The aim of this study was to evaluate the neuroprotective effect of bioaccessible wWPP against hypoxia in 3D models of the SH-SY5Y human neuroblastoma cell line Cells were treated with 1.5 μg GAE/mL of bioaccessible wWPP and then subjected to hypoxia induced by CoCl₂. Cell viability, ROS levels, and gene expression were assessed. Hypoxia significantly increased the expression of the hypoxia-inducible factor gene(HIF1), cell deathand ROS levels, while pretreatment with bioaccessible wWPP mitigated these effects. Hypoxia also altered the mRNA expression of Nrf2, NF-kB, and Nrf2 inhibitor (Keap1), resulting in increased NF-kB and Keap1 expression and decreased Nrf2 levels. Bioaccessible wWPP fractions were able to reverse these changes, restoring mRNA expression to control levels and upregulating antioxidant enzymes like SOD2. These results suggest a potential neuroprotective effect of wine pomace and highlight the relevance of using natural products from the food industry in disease prevention. Full article

This study investigated the use of grape/wine pomace as a potential substitute for nitrifying salts in the production and preservation of frankfurters. Red wine pomace (RWP) from Tempranillo and white wine pomace (WWP) from Cayetana grapes were added to frankfurters made with Iberian pig backfat—an underutilized fat rich in oleic acid—at two levels (0.5% and 3% w/w). These new formulations were compared with a control (containing only meat, salt, and spices) and a commercial formulation containing nitrites and ascorbic acid. Analyses were conducted immediately after production and following 45 days of refrigerated storage to evaluate microbiological, color, physicochemical, and textural changes in the frankfurters. The addition of pomace slightly reduced the pH of the frankfurters but did not affect microbial counts during the manufacturing process. Frankfurters with pomace displayed a similar color to the control but showed lower redness compared to the commercial formulation with nitrites. Importantly, pomace reduced lipid and protein oxidation during production and storage. The reduction in lipid oxidation due to the pomace was comparable to the effect of nitrites and ascorbic acid. Furthermore, pomace effectively reduced protein oxidation, unlike nitrites and ascorbic acid, which primarily targeted lipid oxidation. Significant differences in texture were observed between commercial frankfurters and those containing pomace. Despite these variations in the appearance and the texture, the strong protective effect of pomace against oxidative reactions highlights its potential as a natural alternative to synthetic additives, offering a promising solution for the meat industry. Full article

Exploiting by-products from the oenological industry to extract antioxidant chemicals is a shared goal that combines the need to reduce the wine sector’s environmental impact with the need to improve the availability of these biomolecules, according to a circular economy approach. Natural deep eutectic solvents (NaDES) have recently captured researchers’ interest as a safer and more environmentally friendly alternative to traditional solvents due to their effectiveness, low toxicity, and stability. In this work, we set out to investigate several NaDES for the extraction of phenolic chemicals from local monovarietal grape pomace resulting from different vinification procedures (including both red and rosé vinification of Negroamaro and Primitivo grapes; rosé vinification of Susumaniello grapes and white vinification of Chardonnay, Fiano and Malvasia bianca grapes), with the additional goal of generalizing the use of NaDES to extract chemicals of interest from organisms selected from the wide plant biodiversity. Three binary choline chloride-based NaDES (DES-Lac, DES-Tar, and DES-Gly, with lactic acid, tartaric acid, and glycerol as hydrogen bond donors, respectively) were compared to ethanol as a conventional solvent, and the extracts were evaluated using HPLC/MS and colorimetric techniques. The results revealed that each NaDES produces a substantially higher total phenolic yield than ethanol (up to 127.8 mg/g DW from Primitivo rosé grape pomace). DES-Lac and DES-Tar were more effective for anthocyanins extraction; the most abundant compound was malvidin 3-O-glucoside (highest extraction yield with DES-Lac from Susumaniello pomace: 29.4 mg/g DW). Regarding phenolic compounds, DES-Gly was the most effective NaDES producing results comparable to ethanol. Unexpectedly, Chardonnay pomace has the greatest content of astilbin. In most cases, grape pomace extracts obtained by rosé and white vinification provided the maximum yield. As a result, NaDES have emerged as a viable alternative to traditional organic solvent extraction techniques, allowing for higher (or equal) yields while significantly lowering costs, hazards, and environmental impact. Full article

Chicken breasts and burgers (88% breast and 12% backfat) were evaluated for physicochemical characteristics, thiobarbituric acid reactive substances (TBARS), and antioxidant capacity during storage in vacuum or atmosphere conditions for 18 days at 4 °C using the following two formulations: one without incorporating white pomace seasoning (WPS) and another with 3% WPS. The WPS was obtained from white grape skins, a byproduct resulting from the elaboration of white wine. The addition of the WSP decreased the L* values and increased the a* values, resulting in a significant turning toward brown tones in the chicken products. The addition of 3% of WSP led to higher values of ABTS and FRAP, regardless of the type of packaging. Both types of packaging significantly increased the levels of TBARS, although vacuum packaging proved more effective in protecting against lipid oxidation compared to modified atmosphere package (MAP). Additionally, the WSP improved the oxidative stability regarding the TBARS values. In conclusion, the WSP could be a viable alternative to chemical antioxidants and would lead to healthier and innovative chicken products. Full article

The winemaking process generates an annual global production of about 10 million tons of waste consisting of stalks, skin, and seeds. The possible reutilization of wine pomace is strictly linked to its chemical composition. In this preliminary study, three different Sardinian white grapes (Malvasia, Vermentino and Nasco) grown in the same area were evaluated through a whole wine production chain. To reduce environmental impact, all the grapes were treated following the integrated production practice (IPP) strategies. The adopted agronomic methods and the main physico-chemical parameters of the fresh fruits and musts were evaluated. A fully qualitative and quantitative characterization of the phenolic fraction of the pomace extracts was performed by HPLC-DAD after a post-winemaking process. Water and ethanol were utilized as green solvents in the extraction process. Additionally, the entire pomace post-winemaking process was carried out within the winery facilities to reduce energy loss and road transportation. The findings demonstrated that large amounts of beneficial polyphenols are present in pomace extracts, and that the type of grape used, agronomic practices, and winemaking method all influence the quantity and quality of the extracts. The polyphenol concentrations in the Vermentino (28,391.5 ± 7.0 mg/kg) and Malvasia pomace (11,316.3 ± 6.5 mg/kg) were found to be the highest and lowest, respectively. Full article

In this work, a closed-loop strategy for the management and valorization of winery waste was proposed. The exhausted pomace and grape stalks that are typically obtained from white wine industries were used as a source of simple sugars, namely, glucose and fructose, and of lignocellulosic feedstock for the preparation of selective catalysts for the 5-hydroxymethylfurfural (5-HMF) production from fructose. A novel synthetic procedure was developed for the synthesis of iron-sulfonated magnetic biochar catalysts (Fe-SMBCs). Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), BET surface area, porous structure analysis and determination of total amount of acid sites were performed in order to characterize the physico-chemical properties of the synthesized systems. Then, these heterogeneous catalysts were successfully tested via the dehydration of simple sugars into 5-HMF by using methyl isobutyl ketone (MIBK) and gamma valerolactone (GVL) as co-solvents. The optimum 5-HMF yield of 40.9 ± 1.1%mol with a selectivity of 59.8 ± 2.6%mol was achieved by adopting the following optimized conditions: 0.1 g of catalyst, volume ratio of GVL to H₂O = 2 to 1, 403 K, 6 h. In addition, the catalyst was easily recycled using an external magnetic field and used for at least five reaction cycles without significant loss of catalytic activity. Full article

The use of by-products as functional ingredients for bread recipes may open up new horizons in terms of product innovation to increase nutraceutical characteristics and/or shelf-life. In this research, the ability of residual products from important food chains (Citrus and wine) to influence the water binding capacity of dough and bread was investigated in order to create industrial breads of high quality with prolonged shelf-life in the absence of any chemical additives (e.g., ethanol, sorbic acid, and propionic acid). The product under study is the ‘Pan Bauletto bianco con olio EVO’ (white bakery bread with EVO oil), an ‘industrial bread’ type usually treated with ethanol before being marketed, aiming to prolong its short shelf-life. The effect of the addition of different amounts of pectin (Citrus supply chain) and grape pomace (wine supply chain), in combination or not, has shown promising results from both a technological point of view and the increasing shelf-life, allowing to obtain products with high nutraceutical value and interesting properties. Full article

White wine pomace, a by-product from winemaking, was stabilized after the application of thermal blanching (with the aim of deactivating the polyphenoloxidase enzyme), milling, and processing by hydrostatic high-pressure treatment (with the aim of reducing initial microbial loads while preserving phenolic compounds content). The valorized pomace (VP) ingredient was added at different proportions to pork burgers (0.5%, 1%, and 3% w/w) to improve their preservation, and the effect was compared to those produced by sulfites and with a control (without sulfites or VP). Burgers were vacuum-packed and refrigerated for 7 days. Microbiological, color, oxidation, and sensory parameters were analyzed. Neither sulfites nor VP reduced the microbial development of most microorganism groups evaluated (p > 0.05); however, both prevented coliform growth during storage (p < 0.01). The use of sulfites prevented the discoloration of burgers during storage, while VP had no effect (p < 0.001). On the contrary, VP limited lipid and protein oxidation development during storage (p > 0.05), while sulfites had no effect. Therefore, the use of VP from white wine production could have an antioxidant effect but a limited antimicrobial or color-protective effect for the preservation of pork burgers. Full article

Hyperglycemia is a significant risk factor in metabolic syndrome, contributing to the development of cardiovascular diseases and diabetes mellitus. Hyperglycemia increases ROS (reactive oxygen species) production via glucose oxidation and protein glycosylation, leading to cell damage. Our previous studies have highlighted the antioxidant properties of wine pomace products (wWPPs), a co-product of winemaking, and their ability to modulate oxidative stress. The objective of this study was to evaluate the protective effect of wWPPs against oxidative stress in hyperglycemic Caco-2 cells. They were treated with 1.5 μg GAE/mL of wWPP bioaccessible fractions, obtained from gastrointestinal digestion (WPGI) and colonic fermentation (WPF), under normoglycemic or hyperglycemic (35 mM glucose) conditions. After 24 h of treatment, cell viability, oxidative stress biomarkers and the expression of transcription factors and enzymes involved in cellular oxidation balance were evaluated. Hyperglycemia induced a 30% reduction in cell viability, which was restored to normoglycemic levels by WPF treatment. The bioaccessible fractions were able to counteract hyperglycemia-induced oxidative stress in intestinal cells, as evidenced by significant decreases in carbonyl groups and MDA levels (10 and 40%, respectively). Furthermore, hyperglycemia-induced NF-κB overexpression was also significantly reduced by WPGI and WPF pre-treatment (between 15 and 53%), modulating the redox activity. In conclusion, the bioaccessible fractions of wWPP, particularly WPF, demonstrated significant potential in mitigating hyperglycemia-induced oxidative stress and enhancing cell viability in Caco-2 cells. Full article

Grape pomace is one of the main by-products in the wine industry and contains some high-added-value compounds, such as polysaccharides. Considering the wide application possibilities of polysaccharides in wine and in the food industry, the revalorization of grape pomace to extract polysaccharides presents itself as an opportunity for by-product management. Therefore, the aim of this study was to characterize polysaccharide extracts obtained from pomace by-products of different white grape varieties. The type and content of polysaccharides, proteins and phenols were analyzed. Statistically significant differences were found between the varietal extracts in the types and concentrations of polysaccharides. The extracts obtained from the Verdejo and Puesta en Cruz varieties showed the highest polysaccharide purity and contents, but the type of polysaccharides was different in each case. The Verdejo provided extracts richer in non-pectic polysaccharides, while the Puesta en Cruz provided extracts richer in pectic polysaccharides. The protein and polyphenol contents were low in all extracts, below 2.5% and 3.7%, respectively. These results open up a new possibility for the revalorization of grape pomace by-products to obtain polysaccharide-rich extracts, although it would be interesting to improve both the yield and the purity of the extracts obtained by studying other extraction techniques or processes. Full article

Many authors have investigated the role of mannoproteins on wine quality, but very few have analyzed the use of grape-derived polysaccharides as they are not commercially available. In this study, purified grape-derived polysaccharides from red wine (WPP) and winemaking by-products (DWRP: Distilled Washing Residues Polysaccharides) were used as potential fining agents to modulate white wine flavor. Phenolics and volatile compounds were analyzed in the control and wines treated with WPP, DWRP, and commercial mannoproteins (CMs) after one and twelve months of bottling, and a sensory analysis was conducted. WPP and DWRP, rich in rhamnogalacturonans-II, showed themselves to be good modulators of wine aroma and astringency. Improvement in wine aroma was related to an increase in all volatile families expect higher alcohols and volatile acids. The modulation of astringency and bitterness was related to a reduction in the proanthocyanidin content and its mean degree of polymerization. Extracts with polysaccharides with higher protein contents presented a higher retention of volatile compounds, and DWRP extract had more positive effects on the overall aroma. Our novel results present the possibility of obtaining valuable polysaccharides from distilled washing residues of wine pomaces, which could promote its valorization as a by-product. This is the first time the potential use of this by-product has been described. Full article