Search Results (407)

The stability of upstream tailings remains a critical geotechnical challenge due to the inherently weak mechanical properties of fine-grained mine tailings. This study investigated a tailing improvement method using (i) emulsified polymer and (ii) combinations of recycled gypsum and cement kiln dust (CKD). A comprehensive experimental program—including unconfined compressive strength (UCS) analysis, direct shear tests (DSTs), and oedometer consolidation tests—was conducted to assess the performance of various treatment mixtures. The results showed that blends of CKD and gypsum, particularly at a 1:2 ratio and a 10% dosage, significantly improved shear strength, reduced compressibility, and lowered hydraulic conductivity by over an order of magnitude. The inclusion of plaster (commercial gypsum) further enhanced the UCS by more than 100% compared to recycled gypsum and increased the cohesion (c’) values from 0 to 32.8–47.2 kPa. The compression index (c_c) decreased from 0.15 to 0.05, and the maximum volumetric strain (ε_v) at an applied effective stress of 800 kPa decreased from 17% to 5%. Emulsified polymer treatments also enhanced the mechanical and hydraulic properties of the clayey tailings; however, the overall improvements were lower than those achieved with CKD–gypsum blends, suggesting that further optimization of the polymer concentration or its combination with mineral additives may yield better results. These findings offer a foundation for further research into the use of polymers in geoenvironmental applications, particularly for erosion control, contaminant encapsulation, and hydraulic barrier development. Overall, this study highlights the potential of using industrial by-products, such as CKD and gypsum, as sustainable, cost-effective materials to improve tailing performance, while identifying promising directions for polymer-based solutions in geotechnical engineering. Full article

Brewer’s spent grain (BSG) is an abundant by-product rich in proteins and polysaccharides. This study evaluated ultrasound (US) to enhance alkaline protein extraction in 110 mM NaOH and to obtain a polysaccharide-enriched residue, with mechanical agitation (AG) as the control. First, 40 min extraction curves were evaluated at 25 and 50 °C and fitted to the Weibull model. At 25 °C, US increased the 40 min protein yield (40.8 ± 0.1 g/100 g initial protein) by 2.5-fold compared with AG; heating increased AG yield, whereas US showed negligible temperature sensitivity between 25 and 50 °C. Subsequently, extractions were performed at 25 °C in one or two 20 min cycles using fresh solvent. Extracts were recovered by pH-shift precipitation and freeze-dried. US maximised protein recovery (47.6 ± 0.1 g/100 g initial protein after two cycles) but co-extracted other compounds, reducing purity. AG extracts showed higher emulsifying activity (up to 9.6 ± 0.1 m²·g⁻¹), while US increased emulsion stability (up to 46 min). US residues showed up to ~35% lower glucose content than BSG (42 ± 2 g/100 g dry matter for BSG) and higher arabinoxylans (up to 23.5 ± 0.6 g/100 g dry matter; ~2.4-fold BSG), supporting a dual valorisation route based on the production of a protein-rich extract and an arabinoxylans-rich concentrate. Full article

This research aimed to evaluate the effects of formulation and process conditions on the physical and structural properties of starch–brewers’ spent grain films. Three factors were considered: BSG amounts (0, 1, 3, 5%), a possible ultrasonication pre-treatment, and different microwave gelatinization treatments (450 W for 80 and 90 s; 900 W for 45 and 50 s). An increase in BSG is responsible for increases in moisture (10.72 → 23.40%), water absorption (67.65 → 95.73%), density (0.90 → 1.27 g/cm³), browning index (5.86 → 85.88), UV blocking capacity (82.42% → 99.96% for UV_A; 61.28% → 99.86% for UV_B), and degradability in the first 7 days (58.72 → 66.57%), but dramatically decreases the Young’s modulus and tensile strength (fallen to 2.90 N/mm² and 0.21 N/mm², at 5% BSG). Sonication contributes to increased browning index (36.17 → 37.24), UV blocking capacity, solubility (49.35 → 51.49%) and Young’s modulus (4.40 → 4.77 N/mm²). The most severe microwave treatment (900 W, 50 s) minimizes moisture (15.83%) and water absorption (80.89%) and maximizes density (1.21 g/cm³), browning index (37.52), and Young’s modulus (5.37 N/mm²). SEM micrographs allow us to observe that the film surface appears rough, and the structure becomes increasingly porous as BSG % increases. The regression analysis indicates that the quadratic model effectively describes the relationships between the three factors and each of the most important properties of the films; it is suitable for predicting film behavior and optimizing their characteristics depending on the desired use. Full article

Brewer’s spent grain (BSG) is an abundant lignocellulosic by-product whose valorization can support circular bioeconomy strategies. This study evaluated BSG bioconversion by Aspergillus oryzae ATCC 10124 under solid-state fermentation (SSF) to produce lignocellulolytic enzymes and release second-generation (2G) sugars relevant to biorefinery applications. SSF was monitored over 0–10 days, and FPase, endo-cellulase, β-glucosidase, xylanase, mannanase, amylase, and ligninolytic enzyme activities were quantified. Enzymatic crude extracts were further assessed in SDS-PAGE analysis. Glucose, cellobiose, xylose and arabinose release and consumption were tracked throughout fermentation, and substrate transformation was supported by FTIR. The secretome exhibited a predominantly hydrolytic profile, with maximal hemicellulolytic and cellulolytic activity around days 2–4, as well as sustained amylase activity. Ligninolytic activity was not detected. Sugar profiles indicated rapid early hydrolysis of glucose, followed by progressive pentose release. The stabilization and decline were consistent with fungal uptake. Changes in the carbohydrate fingerprint and SDS–PAGE banding supported structural polysaccharide remodeling and hydrolytic protein secretion. Thus, this SSF platform confirmed certain potential for low-cost cellulolytic and hemicellulolytic enzyme generation. However, because sugar accumulation was temporary and followed by consumption, this system is best interpreted as a biological pretreatment and enzyme-generation step that supports subsequent downstream valorization. Full article

This study evaluated how a partial substitution of pea protein isolate (PPI) with brewer’s spent grain (BSG) or barley rootlets (BRs) affects high-moisture meat analogues (HMMAs). PPI was substituted with 10% and 20% with BSG or BRs, respectively. Extrudates were produced on a co-rotating twin-screw extruder at maximum temperatures of 140 °C and 160 °C. Extrudates were assessed for colour, moisture, firmness and fibre morphology. Furthermore, the technofunctional and nutritional properties of the raw materials were determined. Extrudates with BSG produced the darkest colour, whereas PPI and BR formulations exhibited the lightest. A stronger reddish tint was observed at 160 °C, while the colour within the yellow–blue spectrum was largely temperature-independent. Firmness was generally higher at 160 °C, consistent with lower end-product moisture. Side stream addition lowered protein content and weakened fibre formation, with the effect most pronounced for BRs. Overall, formulation was the dominant factor influencing lightness, while temperature modestly increased redness and firmness. Preliminary sensory evaluation supported these trends. Extrudates produced at 140 °C were perceived as having a more fibrous structure. Higher substitution levels resulted in a weaker, more crumbly texture. With respect to the environmental assessment, a 20% replacement of PPI with BRs or BSG reduced overall environmental impacts by up to 19% and climate impacts by up to 16%. With regard to the novel food status, the EU Novel Food Status Catalogue classifies BSG as not novel, whereas BRs are not novel only when used in food supplements. Any other food uses, other than as, or in, food supplements, might considered to be novel and consequently might need to be authorised under the novel food regulation framework prior to market placement. Full article

This study investigated the development of a perlite waste-based geopolymer for stabilizing iron ore tailings byproduct (IOTB) for geotechnical applications. Mixtures containing 70/30 and 80/20 proportions of byproduct and geopolymer were produced using perlite waste as the precursor and NaOH as the alkaline activator through the one-part method. Raw and geopolymer-stabilized IOTB, air-cured for 7, 14, and 28 days, were evaluated by ICP-OES, XRF, pH, geotechnical characterization, compaction, permeability, SEM, and consolidated drained triaxial tests under confining stresses ranging from 250 to 2000 kPa. The selected mixture presented a maximum dry density of 1.8 g/cm³ and optimum moisture content of approximately 14%. XRD results indicated sodium aluminosilicate phases associated with geopolymerization, with mechanical characteristics comparable to feldspar-type structures, while the pH increased from 6.5 to 12.5. Triaxial tests indicated that elastoplastic behavior persisted regardless of the geopolymer addition; however, SEM images confirmed matrix–particle bonding at grain contacts without significant pore filling. The cohesive intercept increased from 0 kPa in the IOTB to 89.1 kPa and 179.2 kPa after 14 and 28 days of curing, respectively, while the friction angle showed a slight increase of up to 7.7%. Deviatoric stress at failure and energy absorption capacity also increased with curing time. Hydraulically, the permeability coefficient remained within the same order of magnitude (10⁻⁴ cm/s), varying from raw IOTB of 2.73 × 10⁻⁴ cm/s to 3.28 × 10⁻⁴ cm/s after 28 days. These results demonstrated that geopolymer stabilization enhanced mechanical performance without compromising drainage capacity, representing a technically viable and socio-environmentally sustainable solution. Full article

Brewer’s spent grain (BSG) is one of the major by-products of the brewing industry and an abundant lignocellulosic stream with potential for energy recovery and broader biorefinery use. This review evaluates the main BSG-to-energy pathways, including anaerobic digestion (AD), combustion/co-combustion, pyrolysis, gasification, and hydrothermal processes (HTC/HTL), with emphasis on technical performance, environmental aspects, implementation constraints, and integration into brewery systems. Particular attention is given to the effect of BSG heterogeneity, high moisture content, protein and ash composition, and storage instability on process selection and operability. In addition to summarizing pathway-specific evidence, the manuscript proposes a harmonized comparative framework and an integrated technical–economic–environmental interpretation of BSG valorization options. The analysis shows that wet-feed-compatible pathways, especially AD and hydrothermal processing, are generally better aligned with the intrinsic properties of fresh BSG, whereas thermochemical routes usually require more intensive feedstock conditioning and tighter control of ash-related and gas cleaning risks. The review also highlights that long-term operational reliability, scale-up constraints, and utility integration are as important as nominal conversion efficiency when assessing practical deployment. Current evidence suggests that the most realistic implementation strategies are context-dependent and should be selected according to brewery scale, energy demand profile, available heat integration, and acceptable operational risk. Future research should prioritize harmonized reporting, long-term industrial validation, and the development of robust hybrid systems and brewery-integrated biorefinery configurations. Full article

Chrome tanning of fish skins generates hazardous effluents and carcinogenic Cr(VI) residues; chromium-free routes to valorize collagen-rich by-products from aquaculture and coastal fisheries are therefore needed. We report a 12-stage ecological protocol employing acetic acid/NaCl pickling, Acacia mearnsii tannin, A. podalyriifolia retanning, mashed-papaya enzymatic bating, and cinnamon as antimicrobial/odor adjunct, scaled from bench to pilot using exclusively locally sourced inputs, for Nile tilapia (Oreochromis niloticus) and Patagonian flounder (Paralichthys patagonicus). Three trained operators evaluated macroscopic quality against five predefined criteria adapted from SATRA and ISO 3376 grading conventions, providing a structured feasibility baseline that does not substitute for the standardized instrumental testing designated as priority future work. Both species achieved satisfactory grain stability, complete tannin penetration, pliable handle, and cinnamon-dominant odor without residual amines; dark-brown coloration is a recognized practical limitation for fashion applications. In silico molecular docking (GNINA v1.0) was used to explore the mechanistic plausibility of each ecological substitution, generating testable hypotheses rather than definitive mechanistic conclusions: the multidentate polyphenol proxy (PGG) exhibited consistently superior collagen engagement over the flavanol monomer across both collagen constructs and all three scoring metrics (1CAG: Vina affinity −5.51 ± 0.13 vs. −3.54 ± 0.35 kcal/mol; CNNscore 0.874 ± 0.009 vs. 0.771 ± 0.010; 7CWK: Vina affinity −6.98 ± 1.43 vs. −4.37 ± 0.16 kcal/mol; CNNscore 0.858 ± 0.024 vs. 0.635 ± 0.094). Dipeptide probes were reproducibly accommodated in the papain catalytic cleft, with the closest configuration reaching 3.997 Å from the catalytic nucleophile (OCS25-SG). Trans-cinnamaldehyde occupied the quorum-sensing pocket with reproducible placement (CNNscore 0.718 ± 0.034) but without score-based selectivity over structural decoys, a result interpreted as hypothesis-generating for future microbiological validation. The protocol is reproducible from bench to pilot and generalizable across two species with distinct dermal architectures. Quantitative physical-mechanical testing (shrinkage temperature, tensile strength, elongation, tear load), CIELab colorimetric analysis, and effluent characterization (COD, BOD₅, total phenolics) are designated as priorities for future validation. Full article

Parboiling enhances the nutritional, structural, and economic value of rice, yet its adoption in the United States remains limited despite rising domestic and export demand. This review summarizes key stages of the parboiling process and their effects on milling yield, grain integrity, nutrient retention, and glycemic response. It outlines major industry challenges, including high energy and water use, uneven heating and drying, handling of defective kernels, limited automation in smaller mills, labor shortages, and emerging climate-related risks. Advances such as vacuum soaking, infrared and microwave-assisted drying, smart sensors, and AI-driven control systems show strong potential to improve efficiency and product quality. Circular-economy strategies, including biomass energy recovery, water reuse, and by-product valorization, offer additional sustainability gains. Continued research, modernization, and policy support are critical to strengthen competitiveness and positioning of the U.S. parboiled rice sector for a more resilient and sustainable future. Full article

Despite recent biotechnological advancements in the brewing industry, the effective valorization of spent grains from craft beer production remains challenging due to the nutritional variability of cereal-based raw materials. This study analyzes the proteins, free amino acids, fatty acids, and mineral composition of spent grains obtained from two beer types brewed with different proportions of maize grits and malted wheat, in order to assess the influence of adjunct composition. Protein content ranged between 25.81% and 28.43%, with higher values observed in the wheat-based spent grain. Total free amino acids were also higher in the wheat-based sample (190.03 mg/100 g) compared to the maize-based variant (178.66 mg/100 g). Both samples showed a similar fatty acid profile dominated by linoleic acid (51.39–51.58%), while phosphorus was the predominant mineral (up to 2700.03 mg/kg). These results suggest that adjunct type influences the nutritional characteristics of spent grains and provide a basis for their differentiated valorization in sustainable agri-food systems. Full article

The pods of pea (Pisum sativum L.), an abundant agroindustry by-product, represents a sustainable source of bioactive compounds. To harness these compounds effectively, this study aimed to optimize the ultrasound-assisted extraction (UAE) of polyphenols and plant pigments (chlorophylls and carotenoids) from pea pod waste using response surface methodology, and to evaluate the encapsulation of the resulting extract with a novel pea-based carrier derived from whole pea grain powder. The optimal conditions for the extraction were a time of 45 min, a solid-to-solvent ratio of 1:48 (w/v), and an ethanol concentration of 58.51% (v/v). The extract obtained under these conditions was encapsulated using pea grain powder and compared with a conventional whey protein carrier. The resulting microencapsulates were characterized in terms of process yield, moisture content, particle size distribution, thermal properties, and phenolic composition. Pea grain powder as a carrier provided higher powder yield, lower moisture content, and improved thermal stability, whereas whey protein allowed slightly higher retention of most bioactive compounds, except for coumaric acid and kaempferol. Overall, these findings highlight pea grain powder as a promising plant-based carrier that supports the valorization of pea pod waste, contributing to the development of sustainable ingredients and a circular economy for legume processing by-products. Full article

This study investigated the impact of including 10% of dried brewers’ grain (BG), grape pomace (GP), or olive cake (OC) in the finishing diets of thirty-two Ovella Galega lambs on their growth parameters and carcass quality. Productive parameters such as live weight, average daily gain (ADG), and subcutaneous fat depots were monitored. The following carcass traits were also evaluated: carcass weight, conformation, fatness degree, morphology, and pH. Moreover, the left-half carcasses were sectioned into the main commercial cuts. Results showed that the type of diet did not significantly affect (p > 0.05) the growth performance and carcass characteristic of the animals. All groups reported similar (p > 0.05) live weights, ADG, and pre-slaughter fat thickness. In the same manner, the lack of significant variations observed in the productive parameters was also reflected in the carcass traits, showing comparable (p > 0.05) weights, dressing percentages, conformation, fatness levels, morphometric measures, and pH among treatments. Furthermore, the commercial value of the animals was not compromised (p > 0.05) by the experimental treatments. Thus, these outcomes suggest that the employment of these agri-food by-products, at moderate levels, could represent a viable and sustainable feeding approach for these autochthonous lambs. Full article

The brewing process generates substantial by-products rich in potentially bioactive compounds (e.g., polyphenols and fermentation metabolites), providing a sustainable and appealing source of cosmetic ingredients. Oil-in-water (O/W) emulsions containing 20% (w/w) aqueous extracts from Bionda Triplo Malto beer, wort, and key brewing by-products (hops, yeast, and spent grain) were developed and evaluated using a combined in vitro–in vivo approach. Aqueous extracts were first screened on human immortalized dermal fibroblasts (BJ-5ta) at 0.25–1 mg/mL for cytocompatibility and antioxidant activity. Within this concentration range, no significant changes in cell viability or intracellular antioxidant capacity under UV stress were detected, suggesting cytocompatibility but limited inherent activity. When incorporated into O/W emulsions and tested at an active-equivalent concentration of 10 mg/mL, the formulations increased fibroblast metabolic activity and antioxidant response. In contrast, free extracts at 10 mg/mL showed concentration-dependent cytotoxicity for some matrices, with beer- and yeast-based emulsions demonstrating the strongest effects. The emulsions exhibited good physicochemical stability (pH ~5.7–6.2; viscosity 4750–5150 mPa·s), passed the ISO 11930:2012 challenge test, and were well tolerated in patch testing. In a double-blind, randomized split-forearm study on 50 healthy volunteers over 30 days, beer, yeast, and spent grain-based formulations improved skin parameters versus baseline. TEWL decreased (e.g., beer: 16.22 ± 5.12 to 10.77 ± 2.22 mg·m⁻²·h⁻¹; yeast: 16.29 ± 5.66 to 10.18 ± 1.08; spent grain: 14.45 ± 4.34 to 11.66 ± 2.28), hydration increased (beer: 35.15 ± 5.93 to 42.26 ± 3.78; yeast: 33.27 ± 4.87 to 42.92 ± 2.48; spent grain: 34.22 ± 5.19 to 41.16 ± 3.17, and elasticity improved for beer and yeast formulations (62.33 ± 3.27 to 70.24 ± 2.12 N/m) and yeast (61.21 ± 4.72 to 72.13 ± 5.55 N/m). Based on these findings, brewing-derived ingredients demonstrate potential as cosmetic actives, with formulation critically determining their clinical efficacy. Full article

Although the market recently shifted toward low- or non-alcoholic drinks, the beer sector is an important branch of industry in Europe. It stimulates local economies and communities, thereby justifying the need for its development. Both economic and environmental benefits could be achieved through proper management of the generated by-products, enabling them to stay in a loop. Such an approach aligns with currently postulated sustainability-oriented trends. Herein, a solution for the simultaneous management of the two main by-products of beer production is described. The spent yeast (SY) was used as a potential binder for brewers’ spent grain (BSG)-based products, representing a highly innovative solution given the state of the art. Using SY without treatment or with minimal addition of common organic acids (citric, succinic, and tartaric) enabled efficient bonding of the final product. It yielded properties similar to those of commercial counterparts, with a flexural modulus exceeding 1 GPa and a flexural strength exceeding 6 MPa. Because of the nature of the applied raw materials and their inherent moisture sensitivity (water contact angle < 50°), the final product was coated with vegetable oil. The applied coating, after thermooxidation-induced crosslinking, protected against moisture and humidity (water contact angle > 80°), potentially broadening its application range. The application potential was confirmed from a technical point of view through the efficient manufacturing of disposable plates. Nevertheless, their implementation in industrial practice must be preceded by meeting proper criteria for food-contact materials related to the stability and odor of the plates and coatings and migration of their components into food products. Full article

Grain byproducts can serve as cost-effective alternatives to corn, but may lead to reduced production performance and increased greenhouse gas emissions. This study aimed to investigate the effects of replacing corn with the grain byproducts (wheat bran, sprayed corn bran) subjected to bacterial-enzymatic fermentation treatment or not in Hu sheep, mainly focusing on production performance, energy-nitrogen metabolism, rumen fermentation and greenhouse gas emissions. A total of fifty-four 6-month-old Hu sheep were divided into three groups, with 6 pens per group and 3 sheep per pen, and then randomly allocated to one of the three dietary groups for 60 days, i.e., a control group (CON), a group (RC) that corn was partially (~42%) replaced with grain byproducts, and a group (BF) that corn was partially replaced by fermented grain byproducts. Compared with the CON group, the RC group showed numerically lower rumen total volatile fatty acid (TVFA) concentration and its propionate proportion, nitrogen retention content (NR; −10.22%) and its retention ratio (NR/NI decreased by 4.27 percentage points, absolute reduction from 24.30% to 20.04%), corresponding to a relative decrease of 17.6%.) as well as a numerically reduced net profit (−2.18%) with a decreased feed price (−¥0.16/kg TMR). Meanwhile, the RC group showed a significant increase in the relative abundance of Methanobrevibacter (p < 0.05), accompanied by numerically higher daily methane emissions (+6.14%) and emission intensity (+4.08%), although these methane-related differences did not reach statistical significance (p > 0.05). Compared to the RC group, the BF group resulted in a numerical increase in feed price (+¥0.03/kg TMR), net profit (+27.93%), TVFA concentration, propionate proportion, NR (+28.17%), NR/NI (an increase of 5.38 percentage points), the relative abundance of Prevotella, Shuttleworthia and Succinivibrio as well as the decrease of fecal nitrogen (FN; −12.29%), daily methane emissions (−8.75%), emission intensity (−5.83%) and the relative abundance of Methanobrevibacter. In summary, replacing dietary corn by 42% with wheat bran and sprayed corn bran numerically reduced formula cost and nitrogen utilization, while increasing methane emissions and methanogens abundance, without significantly affecting growth performance. This combination led to no improvement in economic returns for fattening Hu sheep. Bacterial-enzymatic fermentation treatment of these byproducts could mitigate these drawbacks, being superior energy-nitrogen metabolism and lower greenhouse gas emissions intensity, presenting a potential strategy for cost reduction and efficiency enhancement. Further research with larger sample sizes is warranted to confirm these findings and support broader application. Full article