Search Results (48)

This study aimed to develop novel oleogels using whey protein (WP) and bacterial cellulose nanowhiskers (BCNW) to expand the potential applications of spent coffee grounds oil (SCGO). An emulsion-templated approach was employed to structure SCGO with varying WP:SCGO ratios, while the incorporation of BCNW was evaluated as a potential stabilizing and reinforcing agent. All oleogels behaved as “true” gels (tan δ < 0.1). Rheological analysis revealed that higher WP content significantly increased gel strength, indicating enhanced structural integrity and deformation resistance. The addition of BCNW had a significant reinforcing effect in oleogels with a higher oil content (WP:SCGO 1:5), while its influence was less evident in formulations with lower oil content (WP:SCGO 1:2.5). Notably, depending on the WP:SCGO ratio, the storage modulus (G′) data showed that the oleogels resembled both hard (WP:SCGO 1:2.5) and soft (WP:SCGO 1:5) solid fats, highlighting their potential as fat replacers in a wide range of food applications. Consequently, this study presents a sustainable approach to structuring SCGO while tailoring its rheological behavior, aligning with global efforts to reduce food waste and develop sustainable food products. Full article

In recent years, coffee waste by-products have been incorporated into polymer blends to reduce environmental pollution. In this study, coffee parchment (CP) was incorporated into biodegradable polylactic acid (PLA) and poly (butylene adipate-co-terephthalate) (PBAT) polymer blends to prepare ribbons through the extrusion process. Extracted green coffee bean oil (CO) was used as a plasticizer, and CP was used as a filler with and without functionalization. A solution of chitosan nanoparticles (ChNp) as a coating was applied to the ribbons. For the raw material, proximal analysis of the CP showed cellulose and lignin contents of 53.09 ± 3.42% and 23.60 ± 1.74%, respectively. The morphology of the blends was observed via scanning electron microscopy (SEM). Thermogravimetric analysis (TGA) showed an increase in the ribbons’ thermal stability with the functionalization. The results of differential scanning calorimetry (DSC) revealed better miscibility for the functionalized samples. The mechanical properties showed that with CP incorporation into the blends and with the ChNp coating, the Young’s modulus and the tensile strength decreased with no significant changes in the elongation at break. This work highlights the potential of reusing different by-products from the coffee industry, such as coffee oil from green beans and coffee parchment as a filler, and incorporating them into PLA PBAT biodegradable polymer blend ribbons with a nanostructured antimicrobial coating based on chitosan for future applications in food packaging. Full article

The inherent brittleness of bio-based poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) significantly restricts its industrial applications despite its industrial compostability. Blending with elastomeric polymers addresses mechanical limitations; however, interfacial incompatibility compromises miscibility as our previous work established. Herein, we investigate coffee oil epoxide (COE) as a bio-based plasticizer for PHBV/natural rubber (NR) blends in sustainable packaging applications. COE, derived from spent coffee grounds, was incorporated into PHBV/NR/peroxide/coagent composites via twin-screw extrusion. FTIR spectroscopy with chemometric analysis confirmed successful COE incorporation (intensified CH₂ stretching: 2847, 2920 cm⁻¹; reduced crystallinity), with PCA and PLS-DA accounting for 67.9% and 54.4% of spectral variance. COE incorporation improved optical properties (7.73% increased lightness; 21.9% reduced yellowness). Rheological characterization through Cole–Cole and Han plots demonstrated enhanced phase compatibility in the PHBV/NR/COE blends. Mechanical testing showed characteristic reductions in flexural properties: strength decreased by 16.5% and modulus by 36.8%. Dynamic mechanical analysis revealed PHBV/NR/COE blends exhibited a single relaxation transition at 32 °C versus distinct glass transition temperatures in PHBV/NR blends. Tan δ deconvolution confirmed the transformation from bimodal distribution to a single broadened peak, indicating enhanced interfacial interactions and improved miscibility. These findings demonstrated COE’s potential as a sustainable additive for biodegradable PHBV-based packaging while valorizing food waste. Full article

Biodiesel is a renewable fuel obtained from vegetable or animal oils and a good alternative to fossil fuels. Since the raw material cost constitutes much of the total biodiesel production cost, cheaper waste oils are potential substitutes for vegetable oils in biodiesel production. Coffee is the product with the second-highest trade volume in the world after oil, at approximately 1.5–2 million tons annually, and results in a huge amount of waste. Recycling such waste into fuels is a promising way to solve the waste problem and this waste is potential raw material for biodiesel production. In this study, biodiesel was produced from the oil extracted from Turkish coffee waste, which has approximately 10–15% oil. The molar ratio of methanol to Turkish coffee waste oil (12, 15, 20), catalyst concentration (1, 1.5, 2 wt.%), and time (60, 120 min.) were the studied parameters. Potassium hydroxide and ion exchange resin were used as catalysts in the experiments. The highest biodiesel yield was obtained with potassium hydroxide catalyst, while the results obtained by using ion exchange resin may be improved. After the parametric study was completed for biodiesel production, the physical and chemical properties of the produced biodiesel were compared with the international biodiesel standards. The values of properties were at an acceptable level and are suitable for improvement. Full article

Coffee is one of the most consumed beverages worldwide, producing approximately 6 million tons of spent coffee grounds (SCG) annually, which are often discarded in landfills. SCG contains 12–16% dry basis oil, which can be recovered in various industrial processes, promoting a more circular and sustainable economy. The efficient reuse of SCG depends on the extraction methods employed. This study investigates the influence of key parameters—solvent type, extraction time, temperature, and particle size—on oil extraction, and evaluates the oil quality using FTIR. Scanning electron microscopy (SEM) was also employed to observe microstructural changes in SCG before and after extraction with both polar and non-polar solvents. Four solvents were tested across different particle sizes. The highest oil yield, 14.57 ± 0.42%, was obtained using ethanol with SCG particle sizes between 250–425 µm, 8 h extraction time, and 60 °C. However, an extraction time of 240 min was found to be optimal, yielding 94% of the oil, making it more suitable for industrial applications. For methanol, diethyl ether, and hexane, the maximum oil yields were 8.46 ± 0.49%, 13.51 ± 0.49%, and 13.51 ± 0.15%, respectively. SEM results indicated that polar solvents were more effective at breaking down SCG and extracting oil. FTIR analysis identified characteristic bands typical of vegetable oils, with no indication of phospholipid contamination. Full article

This study introduces biodegradable nursery bags using poly(lactic acid) (PLA), a widely used biodegradable polymer, and spent coffee grounds (SCGs), a byproduct of the brewing process in the coffee industry. SCGs were oil-extracted to produce extracted spent coffee grounds (exSCGs), which were characterized by their physical properties, chemical functionality, and thermal behavior. The exSCGs were blended with PLA at loadings of 5, 10, and 15 wt%. Analysis showed that exSCGs retained 3–5 wt% residual coffee oil, exhibiting a lower surface area (1.1163 m²/g) compared to SCGs (1.5010 m²/g), along with a higher pore volume (1.148 × 10⁻³ cm³/g) and pore size (~410 nm). All PLA/exSCG bio-composite films displayed a light brown color, well-dispersed exSCG particles, and excellent UV light barrier properties, with transmittance reduced to 1–2%. The residual coffee oil acted as a plasticizer, reducing the glass transition temperature, melting temperature, and crystallinity with increasing exSCG content. Mechanical testing revealed enhanced flexibility compared to neat PLA. Soil burial tests showed increased biodegradability with higher exSCG content, supported by SEM analysis revealing cracks around exSCG particles. The PLA/exSCG blend containing 10 wt% exSCGs exhibited optimal performance, with a significant increase in melt flow index (from 4.22 to 8.17 g/10 min) and approximately double the melt strength of neat PLA, balancing processability and mechanical properties. This innovation provides a sustainable alternative to plastic nursery bags, addressing waste valorization and promoting eco-friendly material development for agricultural applications. Full article

Only about 30% of coffee bean mass can be transformed into coffee drinks; thus, a larger fraction ends up as spent coffee grounds (SCGs), which have been mainly disposed of as waste. The promising direction of SCG reuse is in the cosmetic industry. The aim of this study was to prepare stable cosmetic emulsion bases to create a coffee scrub using SCGs. As the emulsion base and its stability are crucial for the production of cosmetic scrubs, eco-friendly emulsifiers based on apricot kernel oil, soya lecithin and a natural emulsifier from olive oil were included in the study. Apricot kernel oil proved to be the only stable emulsifier. The prepared bases were subjected to microscopic analysis and visual assessment of stability. Cosmetic emulsions with this emulsifier are a good base for coffee scrubs, both with glycerine and castor oil, as well as with the addition of macadamia oil. In emulsions with apricot kernel oil emulsifier and castor oil, macadamia oil increases the percentage of droplets with the smallest diameters, improving the stability of the system. Based on this study, it can be concluded that SCGs are a promising raw material for the production of scrubs with a pleasant coffee aroma. Full article

Currently, there is limited research on the utilization of spent coffee grounds (SCG) in asphalt pavement. This study explores using SCG as a novel rejuvenator together with waste cooking oil (WCO) to enhance the performance of aged asphalt (AA). The high-temperature performance of recycled asphalt was preserved using SCG containing oily components. However, the low-temperature performance of long-term aged asphalt could not be completely restored to the level of virgin asphalt. Therefore, various dosages of SCG and WCO were utilized to optimize the recovery of low-temperature properties while maintaining high-temperature performance. The recycled asphalt (RA) was analyzed through conventional indexes, microscopic characteristics, and rheological properties using penetration and softening point tests, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and a dynamic shear rheometer (DSR). The results showed that the G* of W₇S₁₂ increased by 90% relative to virgin asphalt. Additionally, at strain levels of 2.5% and 5%, the fatigue life of W₈S₁₈ was approximately 3.39 times and 2.34 times greater, respectively, than that of the virgin asphalt. The addition of a rejuvenator can enhance the low-temperature cracking resistance of aged asphalt. Moreover, the FTIR results indicated that the regeneration mechanism of recycled asphalt consisted of physical blending. In summary, W₇S₁₂ exhibited the highest high-temperature performance, while W₈S₁₈ demonstrated superior fatigue life. This study may promote the sustainable development of asphalt pavements by utilizing organic waste as a rejuvenator through resource recovery. Full article

The agroindustry generates substantial quantities of byproducts, particularly in coffee production, which yields significant waste, most notably spent coffee grounds (SCGs). This study explores the potential of SCGs as a versatile resource for applications in both food and nonfood sectors. A comprehensive chemical analysis revealed that SCGs consist of 30.2 wt.% cellulose, 25 wt.% hemicellulose, and 12 wt.% lignin. Morphological characterization was performed using field emission scanning electron microscopy (FESEM). Additional analyses included attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis (TGA). ATR-FTIR identified key polysaccharides and oils, whereas TGA offered insights into the thermal degradation behavior of SCGs, confirming the presence of typical plant cell wall components. X-ray diffraction (XRD) patterns revealed low crystallinity, consistent with SCGs’ amorphous structure. Mineral content was assessed using inductively coupled plasma atomic emission spectrometry (ICP-AES) and atomic absorption spectrophotometry (AAS). The results showed that mineral concentrations in SCGs (per 0.01 kg) were within recommended daily intake limits, confirming their safety for potential human consumption. These findings establish SCGs as a valuable lignocellulosic biomass with applications in composite materials. Additionally, it can serve as an organic soil amendment after fermentation to prevent stress on plants. This approach supports effective waste management and advances resource sustainability practices in the agro-industrial sector. Full article

Spent coffee grounds, the main by-product of the coffee-brewing process, were valorized as a renewable source of lipids for the synthesis of novel wax esters and as an alternative and sustainable oil-structuring agent for the production of oleogels. The lipase-catalyzed reactions were implemented using fatty alcohols both under solvent-free conditions and with limonene as an environmentally friendly solvent. Wax esters were evaluated for their ability to formulate olive oil oleogels through the determination of the physical properties of oleogels. Results showed that high conversion yields were achieved when cetyl and behenyl alcohols were applied under solvent-free conditions, achieving a maximum yield of 90.3% and 91.7%, respectively. In the presence of limonene, the highest conversion yields were 88.9% and 94.5% upon the use of cetyl and behenyl alcohols, respectively. The behenyl wax esters exhibited greater oil-structuring properties, regardless of whether they were derived from solvent or solvent-free conditions. Rheological curves showed that the produced oleogels exhibited a strong gel strength, which was enhanced as the wax ester concentration increased. Frequency sweep curves confirmed the formation of a stable three-dimensional oleogel network and revealed the low dependence of the storage modulus on frequency. Overall, this study demonstrated that producing wax esters from renewable lipid sources has the potential to serve as an effective circular economy paradigm for creating novel oleogels with a broad range of applications. Full article

Hydrothermal liquefaction of solid waste has been gaining more and more attention over the last few years. However, the properties of the HTL product, i.e., biocrude, are limiting its direct utilization. As a result, HTL biocrude upgrading is essential to improve its quality. The main objective of the current research is to study the hydrotreatment stabilization of HTL biocrude, produced from spent coffee grounds, utilizing commercial hydrotreated catalysts, and also to investigate the integration of the stabilized biocrude into a light cycle oil (LCO) hydrotreatment plant for coprocessing to target hybrid fuel production. The results have shown that hydrotreatment is a very promising technology that can successfully remove the oxygen content from raw biocrude by hydrodeoxygenation, decarbonylation and decarboxylation reactions, leading to a stabilized product. The stabilized product can be easily blended with the LCO stream of a typical refinery, leading to the production of jet and diesel boiling range hydrocarbons, favoring at the same time the hydrogen consumption of the process. The findings of this manuscript set the basis for future research targeting the production of renewable advanced biofuels from HTL biocrude from municipal waste. Full article

This study aimed to develop a value-added bio-based polymer product for food packaging. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a promising bioplastic with limitations in processability and brittleness, which our group previously addressed by incorporating high-molecular-weight natural rubber (NR) compatibilized with peroxide and coagent. Yet, processability in an industrial setting proved difficult. Coffee oil epoxide (COE), a waste-derived plasticizer, was incorporated into the PHBV/NR/peroxide/coagent matrix via extrusion, and properties of resulting sheets were evaluated. COE incorporation significantly decreased the oxygen and water permeability of the PHBV/NR sheets. Maximum degradation temperature T_peak (°C) increased by ~4.6 °C, and degree of crystallinity decreased by ~15.5% relative to pristine PHBV, indicating good thermal stability. Melting (T_m) and glass transition temperatures (T_g) of the PHBV/NR blend remained unchanged with COE incorporation. X-ray diffraction (XRD) revealed ~10.36% decrease in crystal size for the plasticized blend. Energy-dispersive X-ray analysis (EDAX) and scanning electron microscopy (SEM) confirmed good dispersion with no phase separation. The water uptake capacity of the plasticized blend was reduced by 61.02%, while surface contact angle measurements showed improved water resistance. The plasticized PHBV sheet shows promise for environmentally friendly packaging films due to its high thermal stability, effective barrier properties, and industrial scalability. Full article

The dried husk of the coffee fruit or coffee cherry called cascara has gained a lot of attention recently. Cascara has an added value as a food and food ingredient. The classic use of cascara is infusion in hot water. Chronic inflammation plays a central role in some of the most chronic diseases of our time (e.g., obesity, diabetes, cancer, Alzheimer). A healthy diet can stop inflammation before it compromises human health. Fruits and vegetables, nuts and seeds, some oils and fatty fish, coffee, cocoa and green tea have been proposed as foods that can fight inflammation. Coffee, cocoa and green tea contain phenols with anti-inflammatory properties and caffeine in different concentrations, the highest being in coffee. Recent research has suggested someone who weighs 68 kg would need about 200 mg of caffeine (2 cups of coffee) a day for protection against obesity. For people who experience anxiety from caffeine consumption, it may be best to consider lowering the dosage to a quantity that promotes anti-inflammatory effects. Cascara infusion in soluble powder form, “instant cascara”, can be a good option for people with this condition. The addition of other components can enhance its nutritional value, health benefits, sensorial acceptance and enable more applications. Since cascara has been mainly treated as a by-product, the adoption of the 5S method (sort, set, shine, standardize and sustain) for the production of instant cascara is a good strategy to achieve a safe and tasty product for sustainable health due to its anti-inflammatory and other properties. The 5S method is a five-step methodology that creates a more organized and productive workspace by encouraging operators to improve the work environment and reduce waste. It is an excellent model for the sustainability of coffee manufacturing and to ensure the quality and safety of health-promoting instant cascara. Full article

This research examined the potential for utilizing waste materials generated during the production of dishes/meals and organic waste. Specifically, it evaluated the use of orange peel (OP), spent coffee grounds (SCG), and waste cooking oil in the production of soaps. For the purposes of this study, homemade soaps were made from used food oils using the cold saponification method using sodium hydroxide. During the soap preparation, spent coffee grounds and orange peel were added to the samples in increasing concentrations of 1%, 2.5%, and 5%. The quality of the individual types of homemade soaps was evaluated on the basis of physicochemical properties such as pH, moisture, total alkalinity, total fatty matter, malondialdehyde content, fat content, foaminess, and hardness. All soaps produced using the cooking oil met the ISO quality criteria and reveal a high TFM content, low moisture content, and also very good foam stability and satisfactory foaming stability. However, no relationship was observed between the use of OP and SCG in soap production and these parameters. However, according to the ABTS test, OP and SCG significantly contributed to the antioxidant properties of the soaps, while SCG-impregnated soaps performed slightly better in this respect. Soaps with SCG also had the highest levels of flavonoids. On the other hand, the fillers used for the soap formulation reduced their hardness. All soaps showed 100% solubility in water, thus confirming the biodegradability of the product. This study demonstrated the novel potential of incorporating waste products like orange peel, spent coffee grounds, and waste cooking oil into homemade soaps, highlighting their contributions to its antioxidant properties and water solubility while ensuring high quality standards. Full article

With the increase in population, large amounts of food waste are produced worldwide every day. These leftovers can be used as a source of lignocellulosic waste, oils, and polysaccharides for renewable fuels. In a fixed bed reactor, low-temperature catalytic pyrolysis was investigated using biomass gathered from domestic garbage. Thermogravimetry, under N₂ flow, was used to assess the pyrolysis behavior of tea and coffee grounds, white potato, sweet potato, banana peels, walnut, almonds, and hazelnut shells. A mixture of biomass was also evaluated by thermogravimetry. Waste inorganic materials (marble, limestone, dolomite, bauxite, and spent Fluid Catalytic Cracking (FCC) catalyst) were used as catalysts (16.7% wt.) in the pyrolysis studies at 400 °C in a fixed bed reactor. Yields of bio-oil in the 22–36% wt. range were attained. All of the catalysts promoted gasification and a decrease in the bio-oil carboxylic acids content. The marble dust catalyst increased the bio-oil volatility. The results show that it is possible to valorize lignocellulosic household waste by pyrolysis using inorganic waste materials as catalysts. Full article