Search Results (47)

The growing demand for palladium (Pd) necessitates the development of sustainable and efficient recovery methods. This work presents a green, one-step synthesis of activated carbon (AC) from winemaking waste (grape seeds) via direct pyrolysis, eliminating the need for separate, energy-intensive activation. Remarkably, the AC synthesized at the lowest temperature of 400 °C exhibited the highest Pd(II) adsorption capacity (16.20 mg/g at 50 °C), performing comparably to many literature-reported ACs that underwent complex activation processes. Characterization revealed that this optimal material possessed a favorable point of zero charge (PZC 7.78) and the lowest ash content (4.66%). Higher pyrolysis temperatures (400–800 °C) progressively increased surface basicity (PZC up to 11.00) and carboxylic group content (reaching 0.565 mmol/g at 800 °C). A comprehensive life cycle assessment (LCA) demonstrated the significant environmental advantage of this method, showing a 74% lower total environmental impact and a 92% reduction in acidification potential compared to commercial coal-based AC. These results prove that highly effective Pd(II) recovery can be achieved through a simplified, direct pyrolysis process, offering a sustainable and practical approach for precious metal recycling from waste biomass. Full article

The aim of the study was to assess the biological potential of extracts obtained from the grape pomace of three Vitis vinifera hybrid varieties—Regent, Rondo and Marechal Foch—as a natural source of bioactive compounds, with possible application in cosmetology and dermatology. Grape pomace, which is an important by-product of the winemaking process, is a rich source of polyphenols, flavonoids, anthocyanins and vitamin C, which exhibit antioxidant, anti-inflammatory and cytoprotective properties that are important for skin health. The conducted studies determined the antioxidant activity of the extracts (DPPH) and the content of total phenolic compounds, flavonoids, anthocyanins and vitamin C, Of the varieties analysed: Marechal Foch exhibited the highest antioxidant activity (10 µmol TE/g), while Regent demonstrated the highest flavonoid content (50.42 mg/g) and vitamin C content (35.6 mg/100 g). The Rondo extract had the highest content of anthocyanins (362.36 mg/g) and total phenolic compounds (18.31 mg/g), indicating strong protective potential for skin cells. Regent extract at a concentration of 25 μg/mL was found to have the greatest effect on fibroblast proliferation and migration, significantly increasing the percentage of living cells and the rate of regeneration. This correlates with the high flavonoid content, which is particularly important for skin cells. These results confirm that grape pomace, particularly from the Regent variety, is a valuable source of natural antioxidants with anti-aging and regenerative properties. The use of these raw materials in cosmetic formulations aligns with the principles of the circular economy and the idea of “zero waste”, being an example of the sustainable use of by-products from the wine industry in the production of innovative bio-cosmetics. Full article

The sustainable reuse of agro-industrial effluents requires a detailed understanding of their microbial composition, especially in the context of integrated vineyard–winery ecosystems. This study investigated the bacterial communities present in winery effluents generated during the early stages of red wine production, using samples collected at a winery in the Setúbal Peninsula, Portugal. Metagenomic analysis targeting the 16S rRNA gene was used to characterise microbial diversity and identify taxa with potential relevance for biotechnology and environmental applications. The effluents exhibited a diverse microbiome, including Prevotella paludivivens, species from the Lactobacillus genus, and members of the Clostridiaceae family, the latter representing about 5% of the total community. Functional profiling of lactic acid bacteria revealed the predominance of Oenococcus and Lactobacillus genera, highlighting adaptive traits that may be beneficial under stress conditions. These results suggest that winery effluents, often considered waste, harbour microbial communities with functional potential that extends beyond fermentation, contributing to a broader grape–wine microbial system. The findings emphasise the value of studying winemaking byproducts as reservoirs of microbial diversity and as resources for developing innovative and sustainable applications in biotechnology and environmental management within the wine industry. Full article

Global wine production reached about 226 million hectolitres in 2024, with Europe as the largest producer. The winemaking industry generates substantial amounts of by-products, presenting both economic and environmental challenges, as approximately 30% of processed grapes are discarded as waste. This study evaluates various polyphenol extraction techniques from wine residues, utilising data from the literature. Techniques assessed include subcritical water extraction, ultrasound-assisted extraction, conventional solvent extraction, and microwave-assisted extraction, each preceded by a suitable pretreatment. Results show that the extraction method, temperature, solvent, and feedstock type have a strong influence on environmental impacts. Microwave extraction from exhausted grape marc had the highest impact due to its low yields and high energy use during freeze drying. In contrast, subcritical water extraction from red wine residues was the most sustainable, benefiting from its high efficiency, use of water as a solvent, and the rich polyphenol content of red grape residues. When included, drying was the primary contributor to greenhouse gas emissions. Climate change and energy demand were key impact categories, with a renewable energy scenario potentially reducing impacts by up to 90%. Results demonstrate that no single extraction method is universally best; choices must balance efficiency and energy use. This work supports optimising sustainable polyphenol recovery within circular economy and climate goals. Full article

Grape seeds are a major by-product of the winemaking industry and a great source of bioactive compounds such as polyphenols and proteins. These compounds have a wide range of applications including those in nutraceutical products and cosmetics and within the wine industry itself. Subcritical water extraction (SWE) was explored as a global method to valorize grape seed by-products for their different bioactive compounds in the context of waste valorization, green chemistry (solvent-free extraction), and circular economy. A Box–Behnken design was applied to generate mathematical responses and the ANOVA analysis determined the optimal extraction conditions (pressure, temperature, and time of extraction) for different responses such as total polyphenol content (TPC), antioxidant activity (AA), and total protein (Tprot). Extraction temperature was found to be the most significant factor influencing all responses while pressure had no significant impact on them. Optimal conditions were derived from the mathematical models for each response. For polyphenol extraction, the optimal conditions were as follows: 170 °C and 20 bar for 39 min with 288 mg GAE/g DM. To achieve the highest AA, SWE parameters should be set at 165 °C and 20 bar for 51 min with 332 mg TROLOX/g DM. For the extraction of proteins, it is necessary to work at 105 °C and 20 bar for 10 min (78 mg BSA/g DM) to preserve protein functionality. In comparison, conventional solvent extraction was unable to outperform SWE with values under the SWE results. Given the high content of polyphenols found in the extracts, an HPLC analysis was conducted. The following compounds were detected and quantified: protocatechuic acid (7.75 mg/g extract), gallic acid (6.63 mg/g extract), delphinidin chloride (1.44 mg/g extract), catechin (0.36 mg/g extract), gentisic acid (0.197 mg/g extract), and some epicatechin (0.07 mg/g extract). Additionally, Maillard reaction products (MRPs) were detected at high temperatures, with 5-hydroxymethylfurfural (5-HMF) appearing in extracts processed at 165 °C and above. The presence of MRPs, known for their antioxidant and bioactive properties, may have contributed to the increased AA observed in these extracts. These findings are significant because a solvent-free extraction process like SWE offers a sustainable approach to repurposing winemaking by-products, with potential applications in the wine and food industries. Full article

The increasing pollution and wastage of food and byproducts from agro-industrial production is an increasingly worrying issue. Grape is one of the most diffused fruit crops cultivated, and grape pomace is the main solid byproduct obtained in the winemaking process; interestingly, it is rich in health-beneficial bioactive molecules. In order to recover these molecules, in this work, a green method has been developed, considering two grape pomaces from different cultivars, namely, Petit Verdot and Cabernet Sauvignon. The extraction procedure, as the first step of this process, was carried out with seven selected deep eutectic solvents (DESs). Then, analysis using HPLC-DAD allowed the detection and quantification of eight out of fifteen different phenolic compounds under examination in the extracts produced, including three quercetin glucosides. The evaluation of antioxidant activity, through the DPPH photometric assay, led to the selection of choline chloride/urea 1:2 + 40% water DES extracts as the extracts with the most promising results. Moreover, significant antibacterial activity was also achieved, in particular, for the betaine/lactic acid 1:4 + 40% water DES extract. Further studies will employ this method for numerous cultivars of grape pomaces with the ambitious aim of the production of polyphenol-enriched food and feed supplements. Full article

This study investigates the synthesis and characterization of zein nanoparticles (ZNp) loaded with grape pomace extract (GPE) from Vitis vinifera L. for applications in controlled release and antioxidant delivery. Grape pomace, a byproduct of the winemaking industry, is rich in bioactive compounds, including phenols and flavonoids, which possess antioxidant properties. To overcome the limitations of these compounds, such as photosensitivity and thermal degradation, they were incorporated into zein nanoparticles using the antisolvent technique. The physicochemical properties of the ZNp-GPE system were thoroughly characterized, including size, morphology, ζ-potential, and total phenol content. Results showed high encapsulation efficiency (89–97%) and favorable loading capacities. Characterization techniques, such as scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and dynamic light scattering (DLS), confirmed that GPE was successfully incorporated into the nanoparticles, thereby enhancing their antioxidant properties. The encapsulation process did not significantly alter the spherical morphology of the nanoparticles, and loading GPE resulted in a decrease in particle size. Total phenol content analysis showed that the ZNp-GPE nanoparticles effectively retained these compounds, confirming their potential as efficient delivery systems for antioxidants. This approach not only provides a method for protecting and enhancing the bioavailability of natural antioxidants but also contributes to the valorization of agricultural waste, promoting sustainability in bio-based industries. Full article

After the winemaking process, the residues formed are called wine lees, which represent a mixture of autolyzed yeasts deposited at the bottom of wine-storage tanks. Approximately 2.96 million tons of yeast result from the vinification of 49.4 million tons of grapes. The increased costs of removing these by-products from the wine industry, which is no longer required in the production process, offer us the opportunity to capitalize on various bioactive compounds through the circular economy concept and circular process. Wine lees resulting from the large-scale production of wine represent a raw material for the valorization of phenolic compounds, proteins, and polysaccharides, as well as pigments or organic compounds. The substantial nutrient resources available from wine lees are described extensively in this manuscript and range from vitamins, amino acids, and fatty acids to food supplements, edible packaging, or food products such as bakery products. This review article explores the emerging horizons of winery waste utilization, unveiling the abundance of bioactive compounds and their manifold applications across the industrial realm. Full article

Grape pomace, the primary by-product of winemaking, represents a significant source of valuable aroma compounds with potential applications across various industries. This study reviews the composition and recovery of these compounds, emphasizing the role of grape variety and winemaking methods, including conventional and long-term maceration techniques, in their aromatic profiles. This review examines the diverse categories of aroma compounds found in grape pomace, including terpenes, norisoprenoids, thiols, and esters. It also investigates the impact of factors such as viticultural practices, fermentation methods, and maceration processes on their concentrations and sensory characteristics. The review further discusses the potential of grape pomace valorization, highlighting its importance in creating high-value additives for use in the food, cosmetics, and fragrance industries. Extracted aroma compounds represent a valuable resource with the potential for reuse as additives across diverse industries. This study aims to encourage innovative approaches to waste management in the wine industry, contributing to environmental sustainability and resource efficiency. 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

The wine industry generates high amounts of waste, posing current environmental and economic sustainability challenges. Grape pomace, mainly composed of seeds, skins, and stalks, contains significant amounts of bioactive compounds and constitutes the main solid residue of this industry. Various strategies are being explored for its valorization, from a circular economy perspective. This review provides an updated overview of the composition of grape pomace from winemaking, highlighting sustainable methodologies for extracting phenolic compounds and their potential health benefits, including antioxidant, antimicrobial, antidiabetic, cardioprotective, antiproliferative, anti-aging, and gut health properties. Furthermore, this review explores the potential applications of this agro-industrial waste and its extractable compounds across the food, cosmetic, and pharmaceutical sectors. Full article

Significant agro-industrial waste is produced during the winemaking process, including grape stalks, which are a rich source of the valuable biopolymer holocellulose that can be utilized for biotechnological processes. The purpose of this study was to delignify grape stalks in order to extract holocellulose. Then Lactobacillus plantarum (LP) was immobilized in the interstitial spaces of holocellulose and then coated with natural polymers (chitosan, Ch; and alginate, Al) to create the Holo-LP/Ch/Al complex. A physicochemical analysis of the system revealed strong bacterial immobilization and stability. The efficiency of the complex in adsorbing ochratoxin A (OTA) from wine model solutions was assessed using a Box–Behnken design under various pH, time, and concentration conditions. The results showed that at pH 3.0, 75.39 min, and a complex concentration of 43.82 mg mL⁻¹, the best OTA removal (53.68%) took place. Because of its physicochemical interactions, the complex showed improved OTA adsorption in acidic environments. This study demonstrates the potential of biopolymeric systems based on holocellulose for reducing mycotoxin contamination in beverages and stabilizing bacterial cells. These results offer a viable way to increase food safety and value winemaking by-products. 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

Vitis vinifera L., commonly known as grapes, is one of the most widely cultivated crops worldwide, with over 80% used for wine production. However, the winemaking process generates substantial residues, including grape pomace (GP), wine lees, and wastewater, which can pose significant environmental and economic challenges. Among these, GP stands out not only as a waste product but also as a rich source of polyphenols—bioactive compounds with recognized antioxidant and anti-inflammatory properties. Recent advancements have expanded the application of GP-derived extracts, particularly in the health and food industries, due to their potent bioactive properties. This review provides a comprehensive overview of the valorization of GP, focusing on its phenolic composition and therapeutic potential. It evokes innovative, environmentally friendly extraction techniques and integrated methods for the chemical analysis of these valuable compounds. Additionally, the health benefits of GP polyphenols are explored, with recent experimental findings examining their metabolism and highlighting the key role of gut microbiota in these processes. These insights contribute to a deeper understanding of the biological activity of GP extracts and underscore their growing significance as a high-added-value product. By illustrating how winemaking by-products can be transformed into natural therapeutic agents, this review emphasizes the importance of sustainable development and eco-friendly waste management practices, significantly contributing to the advancement of a circular economy. Full article

Growing consumer demand for environmentally conscious, sustainable, and helpful products has prompted scientists and industry experts worldwide to look for inventive approaches to mitigate the environmental impact, particularly concerning agricultural and industrial waste. Among the by-products of winemaking, grape pomace (skins, seeds, stems) has the potential to be economically valuable as it is rich in value-added compounds (e.g., phenolic compounds, fibers, flavonoids, anthocyanins, terpenoids) related to health (e.g., antioxidant, antimicrobial, anti-inflammatory, cardioprotective effects) and technological issues (e.g., extraction of value-added compounds). These value-added compounds can be extracted using emerging green extraction techniques and then used in the food industry as preservatives, colorants, and for the formulation of functional foods, as well as in the development of smart food packaging. This review provides an overview of the value-added compounds identified in grape pomace, the emerging green extraction, and integrated approaches to extract value-added compounds based on the literature published in the last five years. The potential applications of these value-added compounds have been extensively researched for the food industry. Full article