Search Results (332)

The valorization of industrial mining and organic wastes in construction materials constitutes a key strategy for reducing the environmental impact of the sector. In this context, the present study aims to evaluate the sustainability of innovative Artificial Lightweight Aggregates (ALAs) manufactured from mixtures of inorganic industrial wastes—such as granite and slate cutting sludge and aggregate washing sludge—together with organic wastes, like cork dust, coffee grounds, and olive pits. The methodology included a Life Cycle Assessment (LCA), considering different waste compositions and manufacturing conditions. The results show that the developed ALAs exhibit favorable environmental performance as their bulk density decreases, with an overall environmental impact lower than that of conventional lightweight aggregates made from expanded clay, achieving a reduction in the carbon footprint of up to 7%. Likewise, the comparative analysis reveals that the process stage with the greatest environmental impact is the heat energy required during the sintering stage in the rotary kiln, which in some cases accounts for more than 90% of the total impact. In summary, the results demonstrate the feasibility of obtaining ALAs manufactured solely from waste with a lower carbon footprint compared to traditional expanded clay aggregates. Furthermore, the study highlights that the process stages with the highest contributions to environmental impact are the transport of raw materials and the high-temperature sintering of the ALAs in the rotary kiln. Thus, their production from waste contributes to the valorization of by-products, fostering circular economy strategies and supporting decarbonization processes within the construction sector. Full article

Coffee oil, an increasingly recognized yet underutilized byproduct of spent coffee grounds, has attracted attention due to its diverse lipid composition and minor components. This study systematically investigated the lipid characteristics of coffee oils extracted from both Arabica and Robusta spent coffee grounds subjected to varying roasting degrees. Comprehensive analyses were conducted, mainly regarding oil yield, acid and peroxide values, fatty acid profiles, sn-2 positional fatty acid distribution, triacylglycerol composition, tocopherol content and total Folin-reactive compounds, as well as squalene and sterol profiles. The selected Arabica samples generally showed higher oil yields than Robusta samples, with oil contents ranging from 12.13% to 15.14% and 10.10% to 13.01%, respectively. Arabica coffee oils showed relatively high total tocopherol levels, ranging from 930.35 to 1495.37 mg/kg, whereas Robusta coffee oils ranged from 637.69 to 867.21 mg/kg. Total Folin-reactive compounds varied among samples and should be interpreted as composition-related indicators rather than direct evidence of antioxidant function. In contrast, Robusta coffee oils contained much higher levels of squalene and total sterols, ranging from 97.00 to 170.37 mg/100 g and 787.29 to 1007.92 mg/100 g, respectively. Chemometric analyses showed distinct grouping patterns among the selected coffee oil samples. In the present sample set, the overall lipid profiles were more closely associated with the Arabica and Robusta sample groups than with the assigned roasting levels. These results provide compositional information for the potential use of Arabica coffee oil as a tocopherol- and Folin-reactive compound-rich lipid ingredient. Robusta coffee oil may be further evaluated for applications requiring higher levels of squalene, phytosterols, and relatively saturated lipid structures. This study provides novel insights into the compositional complexity of coffee oil and supports its targeted valorization across various industries. Full article

This review aims to critically examine food industry by-products as potential sources of natural preservatives and to discuss how this evidence can be translated into adolescent food literacy, label interpretation, and critical food choices. Adolescents are increasingly exposed to food labels and claims about “natural,” “clean-label,” “upcycled,” “sustainable,” and “circular” foods, which may not always be transparent or supported by sufficient evidence regarding their safety, efficacy, sensory quality, consumer acceptance, or environmental benefit. Therefore, they need more than nutritional information; they need to interpret labels, question sustainability claims, and understand how food innovations are produced, tested, communicated, and regulated. Food by-products such as fruit and vegetable pomaces, peels, seeds, skins, olive and wine residues, cereal by-products, coffee silverskin, and cocoa residues are promising resources for clean-label preservation and circular food systems because they may contain phenolics, flavonoids, carotenoids, anthocyanins, essential oils, pectin, dietary fibers, and other compounds with antioxidant, antimicrobial, coloring, stabilizing, and texturizing properties. However, the bioactive potential alone does not guarantee that a by-product-derived ingredient is safe, effective, acceptable, scalable, or sustainable. Its use requires extraction, stabilization, real-food validation, safety assessment, sensory optimization, regulatory compliance, and sustainability evaluation. The review concludes that by-product-derived natural preservatives are both technological resources and educational tools. Future research and education should connect food preservation, label interpretation, food safety, sensory quality, sustainability evidence, and consumer decision-making to empower adolescents as critical consumers and informed agents of change in sustainable food systems. Full article

Kombucha is traditionally produced by fermenting Camellia sinensis tea and sugar in a consortium of microorganisms called SCOBY (Symbiotic Culture Of Bacteria and Yeasts). Short- and medium-chain fatty acids and other organic acids in K are mainly produced by acetic acid bacteria, which contribute to the typical K taste. Coffee is one of the most widely consumed beverages in the world and one of the most traded commodities globally. Harvesting during coffee production generates tons of byproducts generally considered of low value, including cascara (CC), composed of dried pulp and skin, and leaves (CL). To date, few studies have investigated the production of short- and medium-chain fatty acids and monosaccharide’s profile during traditional kombucha fermentation, and their composition in kombuchas prepared from substrates other than C. sinensis is even scarcer. This study followed the changes in sugars and the production of short- and medium-chain fatty acids during K fermentation of black tea (BT), CC, and CL and associated their concentrations with physicochemical parameters (total soluble solids (TSS), pH, and titratable acidity (TA)) and the perceived acidity of the beverages evaluated by a trained panel and untrained consumers. BT K, a SCOBY, and 10% sucrose were added to infusions of arabica CC, CL, or BT. The mixture was fermented for 0, 3, 6, and 9 days. Organic acids were analyzed by GC-MS; sucrose and monosaccharides were analyzed by HPLC-RID. The Rate All That Apply (RATA) test was used for sensory analysis. Results were treated by ANOVA–Fisher and Pearson correlation tests with significance at p < 0.05. Glucose, fructose, arabinose, xylose, cellobiose and glycerol were identified in the infusions. On average, sucrose concentration decreased by 28% up to day 9, considering all K samples, accompanied by TSS decrease. Eight organic acids were semi-quantified, with acetic being the major acid in all beverages (8.4 to 1971 mg L⁻¹) and isovaleric being the lead minor acid (0.7 to 17.7 mg L⁻¹). Additional acids identified were: butanoic, 2-methylpropanoic, pentanoic, 3-methylpentanoic, hexanoic, and octanoic acids. TA values and sourness perceived by consumer assessors increased generally, even though in CC Ks, the acid concentration decreased by day 9. TA, sourness, and sparkling and fizzy mouthfeel correlated positively in all Ks. In general, although the total acid concentration was mainly higher on days 3 or 6, CO₂ formation, among other organic acids, probably increased TA and sourness on day 9. Although it is generally accepted that pH and organic acid concentrations are directly associated with sour taste, it is not possible to accurately predict and modify sour taste intensity in kombucha based only on these parameters, given that other factors, such as the production of CO_2, the existence of buffer systems, and the presence of sugars and other soluble solids, will probably affect the perceived acidity and sourness. Full article

This review aims to comprehensively examine spent coffee grounds (SCGs) as a sustainable source of antioxidant and immunomodulatory bioactives, with a specific focus on their capacity to modulate membrane-level signaling through ion channels and G-protein-coupled receptors (GPCRs) in the context of lifestyle-related chronic diseases. SCGs, the major solid by-product of coffee brewing, represent an underutilized yet highly abundant source of bioactive compounds, including chlorogenic acids, phenolic acids, melanoidins, diterpenes, and residual alkaloids. Lifestyle-related chronic diseases, including type 2 diabetes, obesity, cardiovascular disease, and chronic inflammatory disorders, are increasingly recognized as immunometabolic conditions driven by persistent low-grade inflammation, redox imbalance, and dysregulated membrane signaling. This review synthesizes current evidence demonstrating that bioactives contained in SCG extracts exert antioxidant and immunomodulatory effects that extend beyond radical scavenging. Crucially, these compounds also act as modulators of membrane-level signaling, representing a mechanistic perspective that has not been previously integrated for SCGs in the context of chronic disease. The different extraction methodologies and the obtained results are evaluated with the aim to identify the most effective experimental approach and extraction conditions. The paper also discusses how SCG compounds regulate redox-sensitive ion channels (including calcium channels, TRP channels, and potassium channels), and key GPCR pathways (such as GPR120, GPR43, and adenosine receptors), thereby influencing immune cell activation, cytokine production, insulin signaling, and metabolic inflammation. Particular attention is given to the role of microbial fermentation and enzymatic processing in enhancing SCG bioavailability, generating postbiotic metabolites that further engage GPCR–ion channel crosstalk. By integrating extraction approaches, antioxidant chemistry, immunology, membrane signaling, and nutritional metabolism, this review positions SCG as a sustainable functional ingredient capable of restoring immune tolerance and metabolic homeostasis. These insights support the valorization of SCGs within the circular economy framework and highlight their potential application in next-generation immunonutrition strategies for chronic disease prevention and management. Full article

The recovery of antioxidant compounds from agri-food by-products represents a sustainable strategy for active packaging production. However, the compatibility between natural extracts and film-forming techniques plays a key role in determining film formation and properties. In this work, antioxidant extracts obtained from spent coffee grounds and tomato waste were incorporated into zein-based films produced using two different techniques. The objective was to investigate how extract type and processing technique influence film morphology, wettability, thickness, and mechanical properties. The results demonstrated a strong processing-dependent compatibility between extract composition and production techniques. Spent coffee ground extract was successfully incorporated into compact cast films, while tomato waste extract did not allow the formation of homogeneous cast films and required electrospinning to obtain uniform fibrous structures. The incorporation of spent coffee ground extract significantly increased surface wettability and film stiffness, with Young’s modulus reaching 695 MPa. In contrast, electrospun films containing tomato waste extract exhibited lower tensile strength due to their porous fibrous structure, although uniform fibers were obtained. These findings demonstrate that extract chemistry critically affects the suitability of the processing technique and provide useful guidelines for the design of sustainable zein-based active packaging systems derived from agri-food waste valorization. Full article

Coffee is among the most widely consumed beverages globally being cultivated in nearly 80 countries. Its processing generates large quantities of by-products, including mucilage, pulp/husks, silverskin, parchment, and spent coffee grounds. Although traditionally treated as waste, these residues are increasingly recognized as valuable resources rich in bioactive compounds exhibiting antioxidant, antimicrobial, and health-promoting properties. This review explores the antimicrobial potential of coffee by-products, with particular emphasis on their chemical composition and mechanisms of action. Compounds such as caffeine, chlorogenic acids, polyphenols, and melanoidins have demonstrated inhibitory effects against a broad spectrum of bacteria, including both Gram-positive and Gram-negative bacteria. Many of these compounds, which originate from plant’s defensive system or result from Maillard reactions, are known to disrupt microbial membranes, inhibit DNA repair, and interfere with pathogen metabolism. However, the available literature on their antimicrobial effectiveness remains limited. In the context of the rising worldwide concern over antimicrobial resistance, coffee by-products represent a sustainable and promising source of novel antimicrobial agents. Their valorization may support advances in food preservation, pharmaceutical innovation, and waste management practices, contributing to the implementation of a circular economy framework in the coffee industry while promoting environmental, economic, and social sustainability. Full article

Spent coffee grounds (SCGs), a major by-product of coffee consumption, remain an underused source of chlorogenic acid (CGA) and other phenolic constituents. This study investigated an ultrasound-assisted extraction strategy using deep eutectic solvents (DESs) to improve the recovery and phenolic-acid enrichment of SCGs. Among the tested DES formulations, the betaine–acetic acid system gave the best CGA extraction performance and was therefore used for further optimization by response surface methodology. The optimized process, conducted at a liquid-to-solid ratio of 28 mL/g, 75 °C, and 50 min, produced a CGA yield of 15.18 mg CGA/g dried SCG powder, markedly exceeding that achieved with 70% ethanol under comparable conditions. Structural and chemical characterizations helped explain this improvement. Scanning electron microscopy revealed that the DES-based process caused more evident disruption of the SCG matrix, which favored solvent penetration and mass transfer. Fourier-transform infrared spectroscopy confirmed the formation of a hydrogen-bonding network between betaine and acetic acid. Ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry further revealed that the betaine–acetic acid extract was mainly composed of CGA and hydroxycinnamic acid derivatives. The purified extract also displayed strong in vitro antioxidant capacity. Overall, the betaine–acetic acid DES combined with ultrasound provides an effective green approach for recovering CGA-rich phenolic extracts from SCGs. Full article

Food waste fashion—garments produced from agricultural and food industry by-products, such as fruit peels, coffee grounds, and grape marc—represents a radical yet understudied innovation within the circular economy. This study proposes the Fashion Innovation Adoption Model, a novel framework that organizes consumer adoption of fashion innovations across three hierarchical levels: a distal level comprising sociodemographic characteristics, an intermediate cognitive–evaluative level comprising consumer decision-making styles and functional product attribute evaluations, and a proximal psychosocial level comprising attitudes, static and dynamic social norms, and past fashion purchasing behavior. The model is applied for the first time to food waste fashion as a paradigmatic case of radical circular innovation in the textile sector. Hypotheses were tested via structural equation modeling on a sample of 396 Italian consumers. Purchase intention was directly predicted by attitudes, static and dynamic norms, and general fashion purchasing, whereas sustainable fashion purchasing showed no effect. Among product attributes, only sustainability information influenced both attitudes and intentions. Perfectionism and hedonism were positively associated with intention through sustainability information, while impulsivity and habit were negatively associated with intention. Sociodemographics influenced intention only indirectly, via cognitive and normative mechanisms. These findings reveal complex pathways linking psychological profiles and perceived product attributes to circular fashion adoption, with implications for communication strategies emphasizing sustainability information and targeting heterogeneous consumer motivations. Full article

Spent coffee grounds (SCGs) are abundant byproducts generated during coffee processing that are unsuitable for storage and subsequent value-added utilization owing to their high moisture content and water activity (a_w). This study investigated the effects of different infrared power levels (800, 900, and 1000 W) on drying kinetics, product quality, and energy efficiency to determine the preferred drying parameters for SCGs. The initial moisture content and a_w of SCGs were 63.56% (wet basis) and 0.95, respectively. To enhance mechanistic understanding, the drying data were fitted to four mathematical models, with the Midilli and Page models providing the best fit (R² > 0.99). Drying experiments were conducted under a sample thickness of 0.7 cm and a loading of 500 g, with a final moisture content of <10% as the drying endpoint. The results showed that as infrared power increased, drying time decreased from 30 to 24 min and the drying rate significantly increased from 10.32 to 12.77 g H₂O/min (p < 0.05). The drying process was mainly characterized by a falling-rate period, with the effective moisture diffusivity ranging from 0.97 to 1.15 × 10⁻⁸ m²/s and increasing with rising power, indicating that internal moisture diffusion was the dominant drying mechanism. The final a_w of each treatment group was ≤0.60, indicating good storage stability. Color analysis showed that the color differences in treatments at higher power levels (900 W and 1000 W) were significantly lower than those at lower ones (p < 0.05). While the specific energy consumption (SEC) showed a marginal decrease from 5.80 to 5.68 kWh/kg at higher power, a comprehensive evaluation of drying efficiency, quality characteristics, and energy consumption indicated that 1000 W was the preferred infrared drying power under the conditions employed in this study. These results confirm that infrared drying is an efficient stabilization method with strong potential for rapid stabilization of food processing byproducts. Full article

The increasing global burden of cancer, together with the need for more sustainable resource management, has stimulated growing interest in the valorization of agro-industrial plant residues as sources of bioactive compounds with therapeutic potential. This review highlights the potential of plant by-products—including citrus peels, olive leaves, date palm residues, and tea and coffee processing wastes—as sustainable reservoirs of polyphenols and other phytochemicals with significant anticancer activity. Key compounds such as hesperidin and naringenin from citrus peels, oleuropein and hydroxytyrosol from olive leaves, quercetin and syringic acid from date palm residues, and chlorogenic acid and epigallocatechin gallate from tea and coffee by-products have demonstrated promising antitumor effects in both in vitro and in vivo studies. These molecules exert their activity through multiple mechanisms, including the inhibition of cancer cell proliferation, induction of apoptosis, regulation of the cell cycle, and modulation of major oncogenic signaling pathways such as PI3K/AKT, MAPK, NF-κB, and EGFR. For instance, hydroxytyrosol induces apoptosis and cell cycle arrest while inhibiting the PI3K/AKT and MAPK pathways. Quercetin limits metastasis and glycolysis and suppresses VEGF, PKM2, and AKT signaling. Ferulic acid suppresses tumor growth by inhibiting the PI3K/AKT and JAK2/STAT6 pathways, thereby promoting apoptosis (in vitro and in vivo). In addition to their pharmacological potential, the recovery of these compounds from plant waste supports circular economy strategies by reducing environmental impact and promoting the development of value-added products. Future research should focus on optimizing extraction methods, improving bioavailability and stability, and validating safety and efficacy through well-designed preclinical and clinical studies. Full article

The valorization of agricultural and food industry residues represents an important component of the circular bioeconomy, enabling the conversion of waste streams into value-added materials while mitigating environmental pollution. Spent coffee grounds (SCGs), a solid by-product generated during the extraction of coffee beans with hot water or steam, constitute an abundant lignocellulosic biomass residue. Due to their physicochemical properties, SCGs can be used as low-cost adsorbent materials for the treatment of metal-contaminated wastewater, offering a sustainable alternative to traditional synthetic resins. This review summarizes recent research on the application of SCGs for the removal of metal ions from aqueous systems. The adsorption performance of raw and modified SCGs, including materials obtained via carbonization and chemical functionalization, is comparatively evaluated. Furthermore, key operational parameters governing the adsorption process and the corresponding metal removal efficiencies are discussed. Full article

Spent coffee grounds (SCGs) are one of the most abundant agro-industrial by-products worldwide, with 650 kg generated per ton of green coffee processed, corresponding to an estimated global production of 6.7 million tons in 2022/2023. Improper disposal of SCG raises environmental concerns, while their reuse offers opportunities for sustainable resource management and circular economy strategies. This review examines SCG valorization by addressing their chemical composition, functional properties, and key applications in sectors such as food, agriculture, environmental remediation, bioenergy, and selected industrial fields, including pharmaceuticals, cosmetics, construction materials, and functional devices. In this context, it discusses technological approaches, performance outcomes, and implementation considerations, emphasizing the multifunctional potential of SCGs as a renewable feedstock capable of reducing waste, improving resource efficiency, and generating economic value. By consolidating the current state of knowledge and exploring diverse valorization pathways, this work frames SCG utilization within a circular bioeconomy framework and highlights how innovative applications can transform this widely available waste into sustainable and economically valuable products. Full article

The exponential growth of the fruit-processing industry generates significant quantities of organic by-products, such as peels, seeds, and pomace, which represent a rich but underutilized source of bioactive polyphenols. Valorizing these residues is critical for the transition toward a circular bioeconomy, yet conventional extraction methods remain solvent-intensive and kinetically inefficient. This review provides a comprehensive analysis of emerging green extraction technologies, specifically Ultrasound-Assisted (UAE), Microwave-Assisted (MAE), Enzyme-Assisted (EAE), Pressurized Liquid (PLE), and Supercritical Fluid Extraction (SFE), and Pulsed Electric Field (PEF), applied to key industrial matrices including apple, citrus, grape, olive, and coffee. Comparative data demonstrate that intensification technologies significantly outperform conventional maceration, with UAE and MAE reducing processing times by up to 90% while enhancing polyphenol yields by 20–55% through mechanisms such as acoustic cavitation and dipole rotation. Furthermore, high-pressure methods exhibit tunable selectivity, enabling the specific recovery of heat-sensitive anthocyanins and bound phenolics without the use of toxic organic solvents. The study concludes that the future of industrial valorization lies in the adoption of hybrid technologies and sequential biorefinery strategies to achieve high-purity isolates with minimal environmental impact. Full article

Coffee pulp, a by-product of coffee processing and a rich source of bioactive compounds, is a promising raw material for functional beverages. However, the influence of genetic variability among coffee varieties on the functional and sensory properties of pulp infusions remains poorly understood. This study evaluated physicochemical, antioxidant, and sensory properties of infusions from nine Coffea arabica L. varieties. Significant differences among varieties were observed (p < 0.05). The pH ranged from 5.36 to 6.42, and titratable acidity from 0.06 to 0.08 g/100 mL, indicating a mild acidic profile. Antioxidant activity (DPPH) ranged from 460.52 to 1006.03 µmol TE/L, and total phenolic content from 29.47 to 59.27 mg GAE/L. Geisha showed the highest antioxidant activity and phenolic content, while Casiopea exhibited the highest reducing capacity. In contrast, Oro Azteca, Excelencia, and H1 achieved the highest sensory acceptance. Multivariate analysis confirmed clear differentiation among varieties and a separation between bioactive and sensory-related attributes. These findings highlight the role of varietal selection in balancing functional potential and consumer acceptance, supporting the development of functional beverages within a circular economy framework. Full article