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Coffee silverskin (CS) is a by-product of the coffee roasting process that is known for its potential as a fiber source with antioxidant properties. Therefore, this study aimed to provide an overview of the latest research on CS as a potential ingredient for functional foods and to evaluate the effect of adding different amounts of CS on the functional and sensory attributes of chocolate cakes. The addition of CS increased the total dietary fiber content, antioxidant capacity and the contents of extractable and non-extractable phenolics in the cakes. The evaluated sensory attributes were color, smell, taste, texture and overall impression, and they were evaluated according to a 9-point hedonic scale. Internal preference maps were obtained based on the results from acceptance and "intention to buy" tests. In general, the cakes with lower coffee silverskin content (2.6% and 3.6%) had a similar level of acceptance and the cake with 4.6% coffee silverskin content was the least accepted. The most important attributes were taste and overall impression, corresponding to "like slightly" and "like moderately" for the cakes that had better acceptance. Nonetheless, even with the lowest amount of added CS (2.6%), the produced cakes could be regarded as antioxidant fiber sources (with fiber content above 3 g/100 g), thus confirming the potential of CS as a functional food additive. [ABSTRACT FROM AUTHOR]

The sustainable utilization of production wastes in the agri-food sector is an increasing challenge. This work aims to evaluate the applicability of coffee silverskin, the main by-product of coffee roasting, in the formulation of gummy candies. Firstly, the experimental plan envisaged the extraction and characterization of bioactive compounds from coffee silverskin. The influence of different concentrations of coffee silverskin extract (1%, 2%, and 4%) was then evaluated on chemical, physical, microbiological, structural, and sensory gummy candies characteristics for 120 storage days. Candies formulated without coffee silverskin extract were used as control. The results up to 120 days of storage revealed the higher quality of gummy candies enriched with 1%, 2% and 4% coffee silverskin extract not only for their bioactive content, ranging from 147.9 to 161.1 mg GAE Kg -1 of phenolic compounds, but also for their antioxidant activity, with values at the end of storage of 15.06, 30.25, 31.50 and 28.20 µmol TE g-1 respectively in control and gummy candies enriched with 1%, 2% and 4% coffee silverskin extract. Moreover, all the candies enriched with silverskin coffee extract showed better physical and sensory characteristics compared to the control taste. The results show that the proposed use of silver coffee skin improves and preserves the quality of gummy candies and then be employed as an ingredient to improve the quality of confectionery products. [ABSTRACT FROM AUTHOR]

The scientific community's interest in finding an alternative to the term "wastes" for coffee by-products is steadily increasing. The substantial presence of polyphenols, caffeine, and tannins in these wastes could result in the contamination of water and soil, as they exhibit harmful effects on a range of plants, microorganisms, and aquatic organisms. However, these identical antioxidants can extensively be utilized in food packaging applications. In the context of active packaging, the development of bioactive food packaging films based on natural products and coffee industry wastes is of significant importance according to circular economy principles. In this study, the effect of coffee silverskin particles, i.e., waste of the coffee roasting process, and coffee silverskin aqueous extracts on the properties and antioxidant activity of wheat flour-based films with glucose for food packaging applications were evaluated. In addition, chemical structure identification, optical and morphological analysis, color measurements, and physico-chemical characterization of the films were performed, determining their water absorption, film solubility, and degree of swelling. Furthermore, the oxygen and water vapor transition rate and their antioxidant activity were also measured, and it was found that increasing the addition of coffee silverskin particles and aqueous extracts affected the properties of the films. The biocomposite films of wheat flour and glucose with coffee silverskin particles produced in this work exhibited higher tensile stress at break and Young's modulus compared with wheat flour film with no additives. However, a decrease in elongation at break was observed with increasing addition of the silverskin due to the transition from a pure elastomeric material to a crosslinked one following the formation of hydrogen bonds between the additive and the matrix, which was also found in the FTIR spectra. This work offers a new use of wheat flour and coffee silverskin as an inexpensive biocomposite material to produce multifunctional active films for food packaging applications. [ABSTRACT FROM AUTHOR]

Diabetes mellitus (DM) is a major health problem that has reached alarming levels. The valorization of food wastes has become a priority research line in order to achieve a sustainable food industry. Coffee industry generate large amounts of by-products that are rich in bioactive phytochemicals. Coffee Silverskin (CS) is a thin tegument of the outer layer of the coffee bean and is the only by-product of the roasting process. This research was aimed to explore the diabetes-healing effects of CS extract (CSE). Before secondary screening on animals, phytochemical constituent identification, and antioxidant activity were performed. Then, streptozotocin-induced hyperglycemia in Wistar albino rats was carried out. Regular observations and different metabolic parameters were assessed. In vitro results showed that CSE was rich in polyphenols and flavonoids. Current characteristics of CSE include many principal secondary metabolites on HPLC, mainly caffeine and chlorogenic acid. CSE possesses also a significant antioxidant activity. Regarding the in vivo activities, CSE shows promising efficacy in reducing blood glucose level, glycated hemoglobin, total cholesterol, low-density lipoprotein, and hepato-renal biomarkers, and success in elevating body weight, high-density lipoprotein, and insulin levels. The histopathological reports showed significant improvements against liver and kidney damages. Analysis of the obtained data indicates the effect of CSE in improving the complications of diabetes. The overall antidiabetic activity of CSE can be traced to its phytochemical constituents and antioxidant activity. CSE could be a promising antidiabetic agent, thereby enhancing the high added value of this coffee by-product. [ABSTRACT FROM AUTHOR]

Coffee silverskin (CSS) is a by-product released as waste after roasting coffee beans. This by-product can be used as a functional food ingredient as it contains many valuable compounds such as fibers, sugars, phenolic acids, carotenoids, and flavonoids. In this research, the effects of the partial substitution of animal fat with CSS on physicochemical, textural, and sensory properties in chicken patty production were investigated. For this purpose, four different groups of chicken patties were produced in which animal fat was replaced with CSS at different rates (control: 12% fat, SS1: 10% fat + 2% silverskin, SS2: 8% fat + 4% silverskin, SS3: 6% fat + 6% silverskin). The substitution of animal fat with CSS resulted in decreases in pH, moisture content, water activity, and color values while increasing TBARS (Thiobarbituric acid-reactive substances) and moisture retention. The cooking process also significantly affected the physicochemical properties (p < 0.01). Textural parameters, apart from adhesiveness, were affected by the replacement of animal fat with CSS. While hardness increased compared to the control, resilience, and springiness decreased. On the other hand, cohesiveness was similar in control and SS1 but decreased in other ratios. The use of CSS affected all sensory characteristics, and the sensory evaluation scores closest to the control were determined in the group that used 2% CSS instead of animal fat. [ABSTRACT FROM AUTHOR]

In this paper two waste fillers, namely ground tire rubber (GTR) and coffee silverskin (CSS, a waste bio‐product from the coffee‐making process), have been used to produce sustainable ethylene‐propylene‐diene monomer (EPDM) rubber compounds vulcanized on steel sheets to fabricate rubber‐to‐steel bonded systems for industrial roofing applications. The compounds have shown good mechanical performances, with elastic moduli in the range of 13–16 MPa, tensile strength of 13–20 MPa and elongation at break >400%, and strong adhesion to the metal substrate. Moreover, the rubber‐to‐steel bonded systems present good sound insulation properties (mean sound transmission loss [STL] of 39 dB and noise level reduction in simulated hailstones impact tests of 62 dB with respect to bare steel 73 dB). Accelerated UV‐ and thermal‐aging tests have shown excellent adhesion of the compounds to the metal substrate with the CSS acting as an antioxidant agent preventing excessive polymer degradation. The selected waste‐derived materials result in promising fillers for more sustainable rubber compounds. Highlights: Waste fillers were used to produce sustainable rubber compounds.Rubber‐to‐steel bonded systems for roofing applications were produced.Rubber‐to‐steel bonded systems have good sound insulation properties.Rubber‐to‐steel bonded systems have excellent adhesion.Coffee silverskin filler acts as an antioxidant agent. [ABSTRACT FROM AUTHOR]

The Food and Agricultural Organization estimates a 17% loss in the food production chain, making it imperative to adopt scientific and technological approaches to address this issue for sustainability. Industrial food production waste and its value-added applications, particularly in relation to a wide variety of pathogenic microorganisms and the health-related effects have not been thoroughly investigated. This study explores the potential of food production waste extracts—lemon peel (LP), hot trub (HT), and coffee silverskin (CSS) as sources of bioactive compounds. Extraction was conducted using hydro-methanolic extraction with yields in LP (482 mg/1 g) > HT (332 mg/1 g) > CSS (20 mg/1 g). The agar diffusion assay revealed the substantial antibacterial activity of all three extracts against Erwinia Amylovora, Escherichia coli, Bacillus subtilis, and Bacillus aquimaris. All extracts demonstrated activity against Gram-positive and Gram-negative bacteria, displaying minimum inhibitory concentrations effective against pathogenic bacteria like Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella enterica. Total phenolic content (TPC in mg GAE/1g) was 100, 20, and 100 for CSS, HT, and LP, respectively. Antioxidant activity by ABTS indicated IC50 of 3.09, 13.09, and 2.61 for LP, HT, and CSS, respectively. Also, the antioxidant activity of the extracts was further confirmed by DPPH assay with the best activity in CSS (9.84 GAEg−1) and LP (9.77 mg of GAEg−1) rather than in HT (1.45 GAEg−1). No adverse cytotoxic effects on HaCaT cells were observed. Pancreatic amylase inhibition demonstrated antidiabetic potential, with LP showing the highest levels (92%). LC-MS characterization identified polyphenols as the main compounds in CSS, prenylated compounds in HT, and flavanols in LP. The findings imply the potential sustainable use of food production waste in industry. [ABSTRACT FROM AUTHOR]

Aligned with the principles of the circular economy and aiming at the production of environmentally friendly materials for food packaging applications, sustainable biocomposite films based on poly(lactic acid) (PLA) and coffee silverskin (SS), were developed. Coffee silverskin is a by-product of the coffee roasting process, while PLA is one of the most promising bio-based polymers. Several composites were prepared with different loadings of SS, ranging from 2.5 to 20 wt.%, via the solution casting method. The findings indicated that the effective dispersion of coffee silverskin in PLA was successfully accomplished and that a bleaching treatment of the filler leads to better interfacial interaction. The addition of silverskin, in any proportion, did not affect the melting point and glass transition temperature of the polymer matrix or the oxygen permeability of the film. Moreover, the degree of swelling was increased, more so for the films with modified particles, whereas the water vapor transmission rate and permeability increased only after the addition of high amounts (>10%) of surface-treated silverskin. A gradual decrease in color lightness was measured with the increasing concentration of silverskin, and the color was more intense in the untreated samples. The antioxidant activity of the films increased gradually with increasing additions of coffee silverskin due to the presence of compounds such as polyphenols. The chemical treatment of coffee silverskin resulted in the films having improved mechanical properties, as the chemical treatment facilitated stronger bonding between the base material and the additive. Therefore, sustainable composites with enhanced antioxidant activity can be produced by the incorporation of a food industry by-product into a PLA matrix. [ABSTRACT FROM AUTHOR]

The predominant use of synthetic materials, such as fiberglass and polymeric foams, for thermal and acoustic insulation in the construction sector contributes to the recalcitrant waste accumulation in the environment and is not economically sustainable in the long term. This is because they are developed with linear economy standards, they are neither reusable nor recyclable, and, at their end of lifecycle, they are not compostable, with a great amount of them finishing in landfills. This work is focused on the development of natural, self‐growing mycelium‐biocomposites as sustainable alternatives to these conventional synthetic materials. Specifically, fungal mycelium derived from the nonpathogenic fungal strain Pleurotus ostreatus is fed by coffee silverskin flakes, a lignocellulosic agrowaste from roasted coffee seeds, forming 3D biocomposites. The physicochemical properties of the obtained composite are thoroughly investigated, with a final focus on their thermal and acoustic insulation properties. As proved, the natural agrowaste‐mycelium composites possess high porosity and thus low density, good thermal properties, and satisfactory sound absorption capability. Such properties combined with the minimal energetic requirements for their growth and their fully compostable end‐of‐life nature make them valuable alternatives for thermal and acoustic insulation in building construction, among other applications, promoting environmental and economic sustainability. [ABSTRACT FROM AUTHOR]

In this work, coffee silverskin (CSS) fibers were subjected to alkali pretreatment (ALK‐CSS) and alkali pretreatment, followed by a 4‐bar steam explosion process (SEW4). Both treated fibers presented a higher degree of crystallinity, enhanced thermal resistance and also cleaner, rough, and defibrillated surface due to the removal of noncellulosic components, as was shown in scanning electron microscopy, thermogravimetric analysis, Fourier‐transform infrared spectra, and x‐ray diffraction (XRD) results. The SEW4 fibers were incorporated into the poly(butylene adipate‐co‐terephthalate) (PBAT) matrix in contents up to 5% wt. through melt processing. PBAT/SEW4 composites were evaluated by their microstructure, thermal properties, degree of crystallinity, and hydrophilic behavior. XRD results showed PBAT/SEW4 composites with higher degrees of crystallinity and contact angle tests revealed increased composite hydrophobicity with the increase of SEW4 content in the PBAT matrix. This work describes the importance of recovering coffee lignocellulosic waste and producing value‐added by‐products, especially in packaging manufacturing. [ABSTRACT FROM AUTHOR]

Purpose: Achievements in biotechnology have paved the way for the efficient utilization of agricultural and industrial waste, presenting potential opportunities for sustainability and resource optimization. One such waste that has been studied is coffee silverskin (CS), the only waste generated during the coffee roasting process. This paper aims to analyze the potential of CS for biorefinery and explore its value enhancement through biotechnology. Method: The study employed various analytical techniques, including elemental analysis, chromatography methods, and Fourier transform methods, to characterize the CS biomass. Additionally, three formulations for wet granulations of a biofertilizer were prepared to valorize the silverskin. Empirical formulas were used to assess the fatty acid content and key parameters of CS biodiesel precursor. Results: The results revealed that CS, when enriched with microalgae and bindered with glauconite, becomes high-value amendment rich in essential macro- and micronutrients. The optimal biofertilizer composition suggested a ratio of three parts of CS, one part of glauconite, and 5 parts of the Chlorella vulgaris microalgae suspension with the liquid-to-solid ratio of 1.28. The higher heating value, the cetane number, the iodine value, the viscosity, and the density of precursors obtained comply with the requirements of the standard EN 14214. Conclusion: The CS was found to contain significant amounts of palmitic and linoleic acid, which are known to be value-added components in cosmetic formulations and biodiesel production. The high macro and micro-nutrient contents of CS, make it an attractive opportunity to adopt a circular bioeconomy model in the agricultural sector. By transforming organic waste, the coffee roasting industry can achieve the goal of Zero Waste, contributing to a more sustainable and environmentally friendly approach. Highlights Pelleted biofertilizer not reported before has beneficial agronomic properties Optimal biofertilizer composition: CS : glauconite : Chlorella vulgaris suspension (3:1:5) Optimum liquid-to-solid ratio for pellet agglomeration during control process is 1.28 CS biodiesel precursor has good ignition characteristics with a cetane number of 62 Data gaps on the lignin and carbohydrate content in CS have been filled

Coffee silverskin (CS) is a by-product of the coffee roasting process that is known for its potential as a fiber source with antioxidant properties. Therefore, this study aimed to provide an overview of the latest research on CS as a potential ingredient for functional foods and to evaluate the effect of adding different amounts of CS on the functional and sensory attributes of chocolate cakes. The addition of CS increased the total dietary fiber content, antioxidant capacity and the contents of extractable and non-extractable phenolics in the cakes. The evaluated sensory attributes were color, smell, taste, texture and overall impression, and they were evaluated according to a 9-point hedonic scale. Internal preference maps were obtained based on the results from acceptance and “intention to buy” tests. In general, the cakes with lower coffee silverskin content (2.6% and 3.6%) had a similar level of acceptance and the cake with 4.6% coffee silverskin content was the least accepted. The most important attributes were taste and overall impression, corresponding to “like slightly” and “like moderately” for the cakes that had better acceptance. Nonetheless, even with the lowest amount of added CS (2.6%), the produced cakes could be regarded as antioxidant fiber sources (with fiber content above 3 g/100 g), thus confirming the potential of CS as a functional food additive.

This study presents a multidisciplinary approach for dealing with the environmental problems related to agro‐industrial coffee residues. The exploitation of these residues allows biomolecules to be obtained from renewable sources and enables the preparation of CO2‐neutral biocomposites, with the advantages of reducing fossil depletion, avoiding climate‐altering emissions, and limiting plastic pollution. Coffee silverskin (CSS), a by‐product deriving from coffee bean roasting, was subjected to different eco‐friendly extraction processes, such as ultrasound‐assisted, CO2‐supercritical, and water‐subcritical extractions to recover caffeine, phytosterols, and polyphenols. The residues remaining after the extractions were further valorized as fillers into biocomposites based on poly(1,4‐butylene succinate) (PBS). Biocomposites (filler content up to 30 wt%) were prepared by melt mixing, and they were characterized in terms of their thermal, mechanical, and morphological performance. The effect of the presence of residues derived from different extraction procedures on the resulting properties of biocomposites was assessed and discussed, and the ultrasound‐assisted treatment was found to leave the CSS residue as the most compatible with the PBS matrix. The results of this study indicate that the proposed bio‐refinery could successfully and fully valorize the CSS agro‐industrial residues, even in its ultimate step, producing biocomposites characterized by low economic and environmental impact; these new materials will be a possible bio‐alternative to the traditional polymers commonly used by the packaging industry. [ABSTRACT FROM AUTHOR]

Simple Summary: The feeding and nutrition of Hermetia illucens becomes an important issue due to its ability to convert organic by-products obtained from agri-food chains into extremely valuable biomass. In this context, coffee silverskin, a by-product of coffee roasting, enriched with 5%, 10%, 20%, and 25% of microalgae (Schizochytrium limacinum and Isochrysis galbana), was investigated as a basal rearing substrate for H. illucens. The study also analyzed the evaluation of the environmental sustainability of diets. The results showed that the inclusion of microalgae in the diets led to an increase in larval growth performance, especially in larvae fed with S. limacinum. Conversely, the higher the proportion of microalgae, the greater the environmental impact of larval production. Therefore, considering that the 10% S. limacinum inclusion achieved the best waste reduction index and showed only minor differences compared to the higher inclusions of this microalgae, it can be considered a compromise between the nutritional properties of the insects and sustainability. Moreover, considering that the rearing substrate enriched with 10% S. limacinum achieved the best waste reduction index and showed only minor differences in terms of nutritional value of H. illucens prepupae compared to the higher inclusions of this microalgae, it can be considered a compromise for sustainable insect production. Hermetia illucens is a promising insect due to its ability to convert low-value substrates as food chain by-products into highly nutritious feed. Its feeding and nutrition are important issues. The aim of this work was to investigate the effect of different substrates consisting of coffee silverskin, a by-product of the roasting process, enriched with different inclusions of microalgae (5%, 10%, 20%, and 25%), Schizochytrium limacinum, and Isochrysis galbana, combined with the assessment of environmental sustainability by LCA. In general, the addition of microalgae led to an increase in larval growth performance due to the higher content of protein and lipids, although S. limacinum showed the best results with respect to larvae fed with coffee silverskin enriched with I. galbana. A higher prepupal weight was observed in larvae fed with 10%, 20%, and 25% S. limacinum; shorter development times in larvae fed with 25% of both S. limacinum and I. galbana; and a higher growth rate in larvae fed with 25% S. limacinum. The 10% S. limacinum inclusion was only slightly different from the higher inclusions. Furthermore, 10% of S. limacinum achieved the best waste reduction index. The greater the inclusion of microalgae, the greater the environmental impact of larval production. Therefore, the addition of 10% S. limacinum appears to be the best compromise for larval rearing, especially considering that a higher inclusion of microalgae did not yield additional benefits in terms of the nutritional value of H. illucens prepupae. [ABSTRACT FROM AUTHOR]

The global surge in coffee consumption has led to the generation of significant amounts of spent coffee grounds (SCG), a by-product of the brewing process. If it is left unprocessed in the landfill, it will generate methane, one of the greenhouse gases, and therefore accelerate global warming. The intersection of SCG and its potential as a substrate for black soldier fly (BSF) larvae cultivation as one of the pathways for processing SCG becomes intriguing as we seek sustainable waste management solutions. The combination of both nutrition and toxic alkaloids (caffeine) makes SCG and/or other coffee parts intriguing for recycling (or upcycling) via BSF cultivation to generate insect protein. Due to its remarkable capacity to bioconvert organic waste into high-value proteins and fats, the black soldier fly, Hermetia illucens, has garnered attention in waste management and animal feed production. This comprehensive review sheds light on the recent development of using SCG as a substrate for BSF larvae. [ABSTRACT FROM AUTHOR]

Abstract The predominant use of synthetic materials, such as fiberglass and polymeric foams, for thermal and acoustic insulation in the construction sector contributes to the recalcitrant waste accumulation in the environment and is not economically sustainable in the long term. This is because they are developed with linear economy standards, they are neither reusable nor recyclable, and, at their end of lifecycle, they are not compostable, with a great amount of them finishing in landfills. This work is focused on the development of natural, self‐growing mycelium‐biocomposites as sustainable alternatives to these conventional synthetic materials. Specifically, fungal mycelium derived from the nonpathogenic fungal strain Pleurotus ostreatus is fed by coffee silverskin flakes, a lignocellulosic agrowaste from roasted coffee seeds, forming 3D biocomposites. The physicochemical properties of the obtained composite are thoroughly investigated, with a final focus on their thermal and acoustic insulation properties. As proved, the natural agrowaste‐mycelium composites possess high porosity and thus low density, good thermal properties, and satisfactory sound absorption capability. Such properties combined with the minimal energetic requirements for their growth and their fully compostable end‐of‐life nature make them valuable alternatives for thermal and acoustic insulation in building construction, among other applications, promoting environmental and economic sustainability.

Coffee is one of the most significant beverages consumed worldwide. However, the substantial production and consumption of coffee has led to the generation of large amounts of by-products, such as coffee silverskin (CS).The first objective was to study the ultrasound-assisted extraction (UAE) conditions from CS according to a simple factorial design, in order to obtain natural extracts as a source of polyphenols and caffeine with high antioxidant activity. The second objective was to include CS powder (CSP) or ultrasound CS extract (UCSE) in the elaboration of cookies, in order to obtain an enriched food product with potential health benefits for consumers.CS was characterized in terms of moisture, protein, lipids, ash, total dietary fiber, total phenol content (TPC) and antioxidant activity. The UCSE was characterized in terms of extraction yield, TPC, caffeine content and antioxidant activity (ABTS and ORAC assays).The best UCSE used for cookie elaboration was obtained at 60 min and 180 W with the following values: 8.8 %wt; 36.8 mg GAE/g; 62.7 µmol caffeine/g; 491.1 µmol/g (ABTS assay); 1012.4 µmol/g (ORAC assay). Finally, the cookies were sensory and chemically characterized. In the cookies containing UCSE the sensory acceptability was not modified with respect to the control cookies and an increase in TPC and antioxidant activity was achieved. However, the incorporation of CSP lead to a decrease in the acceptability despite the fact that the cookies constitute a source of fiber. Results reinforce the use of green extraction technologies to obtain antioxidants compounds from natural sources.

The scientific community’s interest in finding an alternative to the term “wastes” for coffee by-products is steadily increasing. The substantial presence of polyphenols, caffeine, and tannins in these wastes could result in the contamination of water and soil, as they exhibit harmful effects on a range of plants, microorganisms, and aquatic organisms. However, these identical antioxidants can extensively be utilized in food packaging applications. In the context of active packaging, the development of bioactive food packaging films based on natural products and coffee industry wastes is of significant importance according to circular economy principles. In this study, the effect of coffee silverskin particles, i.e., waste of the coffee roasting process, and coffee silverskin aqueous extracts on the properties and antioxidant activity of wheat flour-based films with glucose for food packaging applications were evaluated. In addition, chemical structure identification, optical and morphological analysis, color measurements, and physico-chemical characterization of the films were performed, determining their water absorption, film solubility, and degree of swelling. Furthermore, the oxygen and water vapor transition rate and their antioxidant activity were also measured, and it was found that increasing the addition of coffee silverskin particles and aqueous extracts affected the properties of the films. The biocomposite films of wheat flour and glucose with coffee silverskin particles produced in this work exhibited higher tensile stress at break and Young’s modulus compared with wheat flour film with no additives. However, a decrease in elongation at break was observed with increasing addition of the silverskin due to the transition from a pure elastomeric material to a crosslinked one following the formation of hydrogen bonds between the additive and the matrix, which was also found in the FTIR spectra. This work offers a new use of wheat flour and coffee silverskin as an inexpensive biocomposite material to produce multifunctional active films for food packaging applications.

Coffee silverskin (CSS) is a by-product released as waste after roasting coffee beans. This by-product can be used as a functional food ingredient as it contains many valuable compounds such as fibers, sugars, phenolic acids, carotenoids, and flavonoids. In this research, the effects of the partial substitution of animal fat with CSS on physicochemical, textural, and sensory properties in chicken patty production were investigated. For this purpose, four different groups of chicken patties were produced in which animal fat was replaced with CSS at different rates (control: 12% fat, SS1: 10% fat + 2% silverskin, SS2: 8% fat + 4% silverskin, SS3: 6% fat + 6% silverskin). The substitution of animal fat with CSS resulted in decreases in pH, moisture content, water activity, and color values while increasing TBARS (Thiobarbituric acid-reactive substances) and moisture retention. The cooking process also significantly affected the physicochemical properties (p < 0.01). Textural parameters, apart from adhesiveness, were affected by the replacement of animal fat with CSS. While hardness increased compared to the control, resilience, and springiness decreased. On the other hand, cohesiveness was similar in control and SS1 but decreased in other ratios. The use of CSS affected all sensory characteristics, and the sensory evaluation scores closest to the control were determined in the group that used 2% CSS instead of animal fat.

The Food and Agricultural Organization estimates a 17% loss in the food production chain, making it imperative to adopt scientific and technological approaches to address this issue for sustainability. Industrial food production waste and its value-added applications, particularly in relation to a wide variety of pathogenic microorganisms and the health-related effects have not been thoroughly investigated. This study explores the potential of food production waste extracts—lemon peel (LP), hot trub (HT), and coffee silverskin (CSS) as sources of bioactive compounds. Extraction was conducted using hydro-methanolic extraction with yields in LP (482 mg/1 g) > HT (332 mg/1 g) > CSS (20 mg/1 g). The agar diffusion assay revealed the substantial antibacterial activity of all three extracts against Erwinia Amylovora, Escherichia coli, Bacillus subtilis, and Bacillus aquimaris. All extracts demonstrated activity against Gram-positive and Gram-negative bacteria, displaying minimum inhibitory concentrations effective against pathogenic bacteria like Listeria monocytogenes, Staphylococcus aureus, Vibrio parahaemolyticus, and Salmonella enterica. Total phenolic content (TPC in mg GAE/1g) was 100, 20, and 100 for CSS, HT, and LP, respectively. Antioxidant activity by ABTS indicated IC50 of 3.09, 13.09, and 2.61 for LP, HT, and CSS, respectively. Also, the antioxidant activity of the extracts was further confirmed by DPPH assay with the best activity in CSS (9.84 GAEg−1) and LP (9.77 mg of GAEg−1) rather than in HT (1.45 GAEg−1). No adverse cytotoxic effects on HaCaT cells were observed. Pancreatic amylase inhibition demonstrated antidiabetic potential, with LP showing the highest levels (92%). LC-MS characterization identified polyphenols as the main compounds in CSS, prenylated compounds in HT, and flavanols in LP. The findings imply the potential sustainable use of food production waste in industry.

The coffee by-product market represents a transformative paradigm in the coffee industry, capitalizing on previously overlooked resources and generating economic value through sustainable practices. We will explore the multifaceted opportunities and economic benefits stemming from the utilization of coffee by-products, and the diverse applications and industries that contribute to its economic significance. The economic value attributed to the coffee by-product market encompasses the overall sum of transactions and economic activities associated with the utilization, processing, and commercialization of coffee by-products. This encompasses the worth derived from diverse applications and industries that harness coffee by-products to generate products, services, and various economic opportunities. Coffee by-products, once considered waste, now serve as valuable feedstock for energy production, driving cost-saving initiatives. From coffee grounds powering biofuel generation to coffee husks fueling biomass energy plants, the industry is witnessing an impactful shift towards renewable and eco-friendly energy sources, mitigating operational expenses and bolstering financial resilience. The convergence of sustainability and innovation finds expression in the food and beverage sector, where coffee cherry pulp and cascara are harnessed for the production of functional food ingredients and nutraceuticals. Leveraging the rich antioxidants and nutritional benefits of coffee by-products, this burgeoning market segment presents lucrative opportunities, while also promoting health-conscious choices for consumers. Apart from its conventional applications, the coffee by-product market has a significant impact on sustainable infrastructure development. Coffee silverskin, renowned for its remarkable insulating properties, presents an opportunity to transform building materials, leading to energy-efficient construction and decreased long-term operational expenses. Furthermore, coffee silverskin offers opportunities for market diversification, particularly in niche segments like artisanal products. Through the transformation of coffee cherry pulp into biochar, agricultural practices experience a rejuvenation, benefiting from improved soil health and enhanced nutrient retention. In conclusion, coffee by-products play a crucial role in driving the coffee industry towards a sustainable future in line with circular economy principles. Coffee by-products possess immense potential to create significant economic opportunities for coffee-producing regions, fostering growth and prosperity within these communities. They can capitalize on their abundant availability of these products and explore various avenues for utilization. The economic value of the coffee by-product market represents a dynamic amalgamation of innovation, environmental consciousness, and sound economic principles. Regulatory support and consumer demand for sustainable practices further amplify the market's potential, creating a compelling incentive for stakeholders to embrace the transformation from waste to wealth. [ABSTRACT FROM AUTHOR]

The examination presented herein sought to establish a novel methodology for the efficient recovery of polyphenolic antioxidants from coffee processing residues, namely coffee silverskin (CSS). The process developed was an ethanol-based organosolv treatment, assisted by acid catalysis, using sulfuric acid or oxalic acid as the catalyst. The first approach was modeling treatment based on severity, where it was found that treatment dependence on time and temperature may well be described by linear relationships. Response surface methodology was then deployed as a consecutive stage, to optimize treatments with regard to catalyst concentration and resident time. In this case, again, linear models could effectively predict polyphenol recovery yield (YTP). For the sulfuric-acid-catalyzed treatment, the maximum theoretic YTP was found to be 10.95 ± 0.44 mg caffeic acid equivalent (CAE) g−1 DM, achieved at CSuAc = 1.5% and t = 300 min. On the other hand, the maximum YTP of 10.30 ± 0.53 could be attained at COxAc = 4%, and t = 300 min. Considering treatment severity, it was concluded that the use of oxalic acid, a food-grade organic acid, instead of sulfuric acid, a corrosive acid, would afford equivalent effects at lower severity. The high-performance liquid chromatography analyses also revealed that the extract produced through the oxalic-acid-catalyzed treatment was more enriched in neochlorogenic and chlorogenic acids, and it exhibited stronger antiradical activity, but weaker ferric-reducing effects. It is proposed that the methodology developed may contribute towards the use of coffee processing wastes as potential sources of bioactive ingredients and the design of novel functional products, in the frame of a more sustainable strategy for coffee processing companies. [ABSTRACT FROM AUTHOR]

Coffee silverskin (CS) is the thin epidermis covering and protecting the coffee bean and it represents the main by-product of the coffee roasting process. CS has recently gained attention due to its high content in bioactive molecules and the growing interest in valuable reutilization of waste products. Drawing inspiration from its biological function, here its potential in cosmetic applications was investigated. CS was recovered from one of the largest coffee roasters located in Switzerland and processed through supercritical CO2 extraction, thereby generating coffee silverskin extract. Chemical profiling of this extract revealed the presence of potent molecules, among which cafestol and kahweol fatty acid esters, as well as acylglycerols, β-sitosterol and caffeine. The CS extract was then dissolved in organic shea butter, yielding the cosmetic active ingredient SLVR'Coffee™. In vitro gene expression studies performed on keratinocytes showed an upregulation of genes involved in oxidative stress responses and skin-barrier functionality upon treatment with the coffee silverskin extract. In vivo, our active protected the skin against Sodium Lauryl Sulfate (SLS)-induced irritation and accelerated its recovery. Furthermore, this active extract improved measured as well as perceived skin hydration in female volunteers, making it an innovative, bioinspired ingredient that comforts the skin and benefits the environment. [ABSTRACT FROM AUTHOR]

This research investigates the effect of extraction parameters on total phenolic content (TPC) and the antioxidant capacity of coffee silverskin (CS) extract using ultrasound-assisted extraction (UAE) in deep eutectic solvent (DES). The optimization was carried out in two stages: (i) the optimization of the UAE condition with the highest TPC; and (ii) a four-factor Box-Behnken design (BBD) to optimize the UAE condition with the optimal TPC; 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity; and ferric reducing antioxidant power (FRAP). The results showed that the optimal UAE condition with the highest TPC was 150–250 μm CS particle size; 1,6-hexanediol as hydrogen bond donor (HBD); 1:7 HBA:HBD molar ratio; and 30% (w/w) water content, given choline chloride (ChCl) as hydrogen bond acceptor (HBA), 30 min extraction time and 30 ° C extraction temperature. The BBD-based optimal UAE condition was 30% w/w water content, 45 mL/g liquid/solid ratio, 90 min extraction time and 85 ° C extraction temperature, given the CS particle size of 150–250 μm and the HBA:HBD molar ratio of 1 (ChCl): 7 (1,6 hexanediol), achieving 19.19 ± 0.20 mg GAE/g CS for TPC, 24.06 ± 1.77 mg TE/g CS for DPPH radical scavenging capacity, and 59.13 ± 4.55 mg Fe (II)/g CS for FRAP. The experimental results were in good agreement with the BBD-based predicted results (22.40 mg GAE/g CS for TPC, 24.09 mg TE/g CS for DPPH, and 59.43 mg Fe(II)/g CS for FRAP). The two-site kinetics model best fitted the experimental data, with R2 of 0.991–0.999.

Hermetia illucens is a promising insect due to its ability to convert low-value substrates as food chain by-products into highly nutritious feed. Its feeding and nutrition are important issues. The aim of this work was to investigate the effect of different substrates consisting of coffee silverskin, a by-product of the roasting process, enriched with different inclusions of microalgae (5%, 10%, 20%, and 25%), Schizochytrium limacinum, and Isochrysis galbana, combined with the assessment of environmental sustainability by LCA. In general, the addition of microalgae led to an increase in larval growth performance due to the higher content of protein and lipids, although S. limacinum showed the best results with respect to larvae fed with coffee silverskin enriched with I. galbana. A higher prepupal weight was observed in larvae fed with 10%, 20%, and 25% S. limacinum; shorter development times in larvae fed with 25% of both S. limacinum and I. galbana; and a higher growth rate in larvae fed with 25% S. limacinum. The 10% S. limacinum inclusion was only slightly different from the higher inclusions. Furthermore, 10% of S. limacinum achieved the best waste reduction index. The greater the inclusion of microalgae, the greater the environmental impact of larval production. Therefore, the addition of 10% S. limacinum appears to be the best compromise for larval rearing, especially considering that a higher inclusion of microalgae did not yield additional benefits in terms of the nutritional value of H. illucens prepupae.

The global surge in coffee consumption has led to the generation of significant amounts of spent coffee grounds (SCG), a by-product of the brewing process. If it is left unprocessed in the landfill, it will generate methane, one of the greenhouse gases, and therefore accelerate global warming. The intersection of SCG and its potential as a substrate for black soldier fly (BSF) larvae cultivation as one of the pathways for processing SCG becomes intriguing as we seek sustainable waste management solutions. The combination of both nutrition and toxic alkaloids (caffeine) makes SCG and/or other coffee parts intriguing for recycling (or upcycling) via BSF cultivation to generate insect protein. Due to its remarkable capacity to bioconvert organic waste into high-value proteins and fats, the black soldier fly, Hermetia illucens, has garnered attention in waste management and animal feed production. This comprehensive review sheds light on the recent development of using SCG as a substrate for BSF larvae.

Coffee, as one of the most consumed beverages, generates a wide variety of waste materials that can be used as biofuels and bio-products. Conventional pyrolysis can be used in rural areas, improving the circular bioeconomy of these places. In this work, the characterization and slow pyrolysis of specialty coffee residues, coffee silverskin (CSS), and spent coffee (SC) were conducted at temperatures from 300 to 600 °C. Physico-chemical and thermal analysis were carried out. In addition, the quantification of individual compounds as acetic, formic, and levulinic acids, caffeine, and other minor compounds was performed. The results indicate the differences between both waste materials in the obtained pyrolysis fractions. The biochar fraction for SC is lower at all temperatures and the liquid fraction higher, reaching maximum values of 62 wt.% in the liquid at 600 °C compared to 47% in CSS. The higher yield in the liquid fraction of SC corresponds to the higher contents of hemicellulose and extractives and the lower ash content. The calculated calorific value for the pyrolysis solid fractions reaches 21.93 MJ/kg in CSS and 26.45 MJ/kg in SC. Finally, biorefinery options of major components of the liquid fraction were also presented. [ABSTRACT FROM AUTHOR]

Upcycling is a modern trend in the cosmetic sector, focusing on by-products reuse and waste reduction. Consumers are more aware of the origin of cosmetic products and their environmental impact, promoting the upcycling phenomenon. Converting these raw materials into products of higher quality or value contributes to the final product's sustainability. In fact, several agri-food by-products that are typically discarded have generated great interest, due to their value-added compounds with high functionality and/or bioactivity. Coffee is well known as a cosmetic ingredient, particularly due to the presence of phenolic compounds, such as chlorogenic acids, and caffeine. Caffeine is widely used in cosmetic formulations due to its photoprotector and anti-aging properties, as well as lipolytic action in cellulitis, and hair regrowth. Chlorogenic acids are powerful antioxidants and exhibit anti-aging and photoprotector abilities. Coffee by-products, such as coffee beans, possess these bioactive compounds and other chemical characteristics that can provide functional properties in cosmetic formulations. Coffee silverskin and spent coffee grounds are high-volume by-products of the coffee industry. Their use has been explored in different cosmetic formulations demonstrating safety, stability, acceptability as well as skin improvement, thus supporting their valorization as natural and sustainable new ingredients in skincare products. [ABSTRACT FROM AUTHOR]

The exploitation of coffee at a global scale increases constantly due to the high demand for this beverage. This activity generates a large number of by-products that are generally discarded, producing a negative environmental impact. In this context, the aim of this study is to take advantage of these elements in different markets of the food industry. There is scarce information on the sensory acceptability and consumer perception in food applications of these by-products. The objective of this study was focused on evaluating these elements, in three conditions: blind, expectant, and informed, of beverages and cookies made with coffee by-products. The acceptability of the products was evaluated by means of a hedonic scale and the Check All That Apply (CATA) test was applied to determine the consumers' perception, both tests in the three evaluation conditions. In general, the acceptability of the beverages was between "I slightly dislike" and "I neither like nor dislike", according to the concentration. The 250 g/L beverage presented a significantly higher acceptability and according to the evaluation condition, the acceptability was higher in the expectant condition. As for the cookies, the acceptability categorized them as products that are slightly disliked to quite liked, there were no significant differences, so it can be deduced that the acceptability of the cookies was not influenced by the amount of byproduct used nor by the evaluation condition. It could be concluded that consumer acceptability and perception of new products can be influenced by the type of product and the information the consumer has about it. [ABSTRACT FROM AUTHOR]

The application of low-cost feed additives as an immunostimulant for different species of fish is an emerging research area in aquaculture. The present study aimed at incorporating a byproduct from coffee processing, coffee silverskin, as an immunostimulant in Nile Tilapia. A total of 225 Tilapia fingerlings (each weighing 23.04±0.07) were fed on diets as follows: Diet 1 (control), Diet 2 (20 gm/kg), Diet 3 (40 gm/kg), Diet 4 (80 gm/kg) and Diet 5 (180 gm/kg) of coffee silverskin. The feeding experiment continued for four weeks; moreover, growth, as well as immunological studies, were carried out by collecting mucus and blood serum from the liver and intestine of the fish. A significant increase in growth performance was observed in fish fed with a 40 gm/kg coffee silverskin-containing diet. The same effect was found in immunological parameters, including complement activity, serum lysozyme activity, and respiratory burst activity. Therefore, it is concluded that the study was definitely a successful one, and a diet with 40 gm/kg of coffee silverskin (Diet 3) was effective, compared to the rest of the compositions.

Probiotic dairy products must contain a certain level of live probiotic microorganisms at the time of consumption. The number of live microorganisms in kefir culture, which is a mixture of different microorganisms, may change during storage due to various factors. In this study, the effects of adding a novel ingredient coffee bean membrane (CSS-coffee silverskin), on the viability of microorganisms contained in kefir culture were investigated. For this purpose, CSS obtained from 2 different coffee varieties (Arabica and Robusta) was added to kefir samples at 3 different concentrations (0.5, 0.75 and 1.0%) at the beginning of fermentation. It was observed that especially the addition of CSS belonging to the Robusta variety significantly increased the viability of lactic acid bacteria (lactobacilli and lactococci) which accounted for 88-94.10 and 82.37-92.44% respectively. During the storage period of 28 days at 4 °C; it could be observed that kefir enrichment with CSS of both coffee varieties increased the viability of lactobacilli and lactococci after in-vitro digestion, depending on the rate of supplementation. Number of yeasts was decreased during the storage.

Although coffee silverskin (CS) has recently been used as a food ingredient, no knowledge has been reported on the effects of species or different post-harvest treatments on its chemical composition. Therefore, the fibre, volatile compounds, phenolic acid content, and antioxidant capacity of CS samples obtained at three roasting intensities (light, medium, and dark) from the Coffea arabica and C. canephora species, each subjected to a washing or a sun-drying ("natural") post-harvest treatment, were studied. Obtained results showed that the chemical composition of CS is due to species, roasting, post-harvest treatment, and interaction. In particular, natural Arabica CS showed the highest content of volatile compounds of Maillard and varietal origin, whereas washed Arabica CS showed the highest content of soluble dietary fibre and chlorogenic derivatives. Pyrroles, sulphur compounds, and pyridines contents were higher in Canephora CS than in Arabica CS. The dark-roasted washed Arabica CS showed the highest content of 5-O- and 3-O-caffeoylquinic acids, while the natural Arabica CS highlighted the highest antioxidant capacity. The effect of post-harvest treatments seemed to be emphasised in Arabica CS, independent of roasting, which did not significantly affect the antioxidant capacity of CS from either species. [ABSTRACT FROM AUTHOR]

The coffee by-product market represents a transformative paradigm in the coffee industry, capitalizing on previously overlooked resources and generating economic value through sustainable practices. We will explore the multifaceted opportunities and economic benefits stemming from the utilization of coffee by-products, and the diverse applications and industries that contribute to its economic significance. The economic value attributed to the coffee by-product market encompasses the overall sum of transactions and economic activities associated with the utilization, processing, and commercialization of coffee by-products. This encompasses the worth derived from diverse applications and industries that harness coffee by-products to generate products, services, and various economic opportunities. Coffee by-products, once considered waste, now serve as valuable feedstock for energy production, driving cost-saving initiatives. From coffee grounds powering biofuel generation to coffee husks fueling biomass energy plants, the industry is witnessing an impactful shift towards renewable and eco-friendly energy sources, mitigating operational expenses and bolstering financial resilience. The convergence of sustainability and innovation finds expression in the food and beverage sector, where coffee cherry pulp and cascara are harnessed for the production of functional food ingredients and nutraceuticals. Leveraging the rich antioxidants and nutritional benefits of coffee by-products, this burgeoning market segment presents lucrative opportunities, while also promoting health-conscious choices for consumers. Apart from its conventional applications, the coffee by-product market has a significant impact on sustainable infrastructure development. Coffee silverskin, renowned for its remarkable insulating properties, presents an opportunity to transform building materials, leading to energy-efficient construction and decreased long-term operational expenses. Furthermore, coffee silverskin offers opportunities for market diversification, particularly in niche segments like artisanal products. Through the transformation of coffee cherry pulp into biochar, agricultural practices experience a rejuvenation, benefiting from improved soil health and enhanced nutrient retention. In conclusion, coffee by-products play a crucial role in driving the coffee industry towards a sustainable future in line with circular economy principles. Coffee by-products possess immense potential to create significant economic opportunities for coffee-producing regions, fostering growth and prosperity within these communities. They can capitalize on their abundant availability of these products and explore various avenues for utilization. The economic value of the coffee by-product market represents a dynamic amalgamation of innovation, environmental consciousness, and sound economic principles. Regulatory support and consumer demand for sustainable practices further amplify the market’s potential, creating a compelling incentive for stakeholders to embrace the transformation from waste to wealth.

The examination presented herein sought to establish a novel methodology for the efficient recovery of polyphenolic antioxidants from coffee processing residues, namely coffee silverskin (CSS). The process developed was an ethanol-based organosolv treatment, assisted by acid catalysis, using sulfuric acid or oxalic acid as the catalyst. The first approach was modeling treatment based on severity, where it was found that treatment dependence on time and temperature may well be described by linear relationships. Response surface methodology was then deployed as a consecutive stage, to optimize treatments with regard to catalyst concentration and resident time. In this case, again, linear models could effectively predict polyphenol recovery yield (YTP). For the sulfuric-acid-catalyzed treatment, the maximum theoretic YTP was found to be 10.95 ± 0.44 mg caffeic acid equivalent (CAE) g−1 DM, achieved at CSuAc = 1.5% and t = 300 min. On the other hand, the maximum YTP of 10.30 ± 0.53 could be attained at COxAc = 4%, and t = 300 min. Considering treatment severity, it was concluded that the use of oxalic acid, a food-grade organic acid, instead of sulfuric acid, a corrosive acid, would afford equivalent effects at lower severity. The high-performance liquid chromatography analyses also revealed that the extract produced through the oxalic-acid-catalyzed treatment was more enriched in neochlorogenic and chlorogenic acids, and it exhibited stronger antiradical activity, but weaker ferric-reducing effects. It is proposed that the methodology developed may contribute towards the use of coffee processing wastes as potential sources of bioactive ingredients and the design of novel functional products, in the frame of a more sustainable strategy for coffee processing companies.

This study pertains to incorporation of coffee silverskin (CSS) in partial replacement for ordinary Portland cement (OPC) in mortar, by investigating its fresh properties (setting and workability), compressive strength (3, 7, 14 and 28-day), absorption and microstructural characteristics. The objectives were to reduce environmental solid wastes and achieve cost efficiency in the use of construction materials. The CSS was expressed as a ratio of total binder (CSS/(OPC + CSS)) and varied from 0 to 5%. The findings revealed that CSS could reduce workability, setting time and early strength. It could also enhance the absorption of the CSS-blended mortar (CBM). The cause of reduction in workability was due to its contribution to the viscosity of the mixture due to the emulsification of the fat component (acetate) and aromatic compounds, as observed in the Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction techniques. The presence of these compounds also caused microstructural disintegration that resulted in the lower strength. In addition, the presence of other organic compound in CSS but absent in OPC enhanced microstructural disintegration and porosity in CBM. The 28-day strength of 25 MPa could be achieved in CSS-blended mortar if the CSS/(CSS + OPC) ratios were kept below 3%. The maximum compressive strength of 38.5 MPa was obtained with the optimum CSS content of 1 wt%. The relative density (water) of CSS was 0.345; therefore, it could also be used to produce lightweight concrete. This study promotes the valorization of raw CSS waste as construction material which could be used for subgrade in the construction of road pavement. [ABSTRACT FROM AUTHOR]

Coffee silverskin (CS) is the only byproduct of the roasting process for coffee beans and is rich in phenolic compounds with various bioactivities. This study proposes a valorization option for bioactive compounds (T-CQA) based on a subcritical water extraction (SWE) technique, which is known for its high efficiency and feasibility for use on an industrial scale. The use of water as a sole solvent requires a minimum number of cleaning steps and renders the extract safe for further applications, such as in either the cosmetic or food industry. Response surface methodology with a Box–Behnken design is effectively used to optimize and explain the individual and interactive process variables (i.e., extraction temperature, extraction time, and solid–liquid ratio) on the T-CQA content obtained from coffee silverskin by the SWE technique. The final model exhibits a precise prediction of the experimental data obtained for the maximum T-CQA content. Under the optimum conditions, the CS extract is found to contain a higher content of T-CQA and TPC than that reported previously. For antioxidant activity, up to 26.12 ± 3.27 mg Trolox equivalent/g CS is obtained. [ABSTRACT FROM AUTHOR]

The application of low-cost feed additives as an immunostimulant for different species of fish is an emerging research area in aquaculture. The present study aimed at incorporating a byproduct from coffee processing, coffee silverskin, as an immunostimulant in Nile Tilapia. A total of 225 Tilapia fingerlings (each weighing 23.04±0.07) were fed on diets as follows: Diet 1 (control), Diet 2 (20 gm/kg), Diet 3 (40 gm/kg), Diet 4 (80 gm/kg) and Diet 5 (180 gm/kg) of coffee silverskin. The feeding experiment continued for four weeks; moreover, growth, as well as immunological studies, were carried out by collecting mucus and blood serum from the liver and intestine of the fish. A significant increase in growth performance was observed in fish fed with a 40 gm/kg coffee silverskin-containing diet. The same effect was found in immunological parameters, including complement activity, serum lysozyme activity, and respiratory burst activity. Therefore, it is concluded that the study was definitely a successful one, and a diet with 40 gm/kg of coffee silverskin (Diet 3) was effective, compared to the rest of the compositions. [ABSTRACT FROM AUTHOR]

Nowadays, there is an increased interest in coffee derivatives (green beans, roasted beans, and coffee by-products (Cascara and Silverskin)) due to their particular chemical composition. This study aimed to compare the content of dry matter, total fat, fatty acids, and fiber (ADF, NDF) of coffee by-products (Cascara and Silverskin) and coffee beans (green and roasted under different conditions). Coffee beans and their by-products were obtained from 100% C. arabica coffee cherries from Panama by dry process. The lowest concentrations of fat corresponded to Cascara 4.24 g·kg−1 and Silverskin 23.70 g·kg−1, respectively. The major fatty acids detected in all samples were palmitic, stearic, oleic, and linoleic acids, the latter two being essential fatty acids. LDA showed that 89.01% of the variability between beans and by-products was explained by lignoceric, myristic, behenic, tricosanoic, arachidic, and heneicosanoic acids. Silverskin appeared to be a good source of lignoceric, myristic, and behenic acids and had a higher concentration of dietary fiber (314.95 g·kg−1) than Cascara (160.03 g·kg−1). Coffee by-products (Silverskin and Cascara) are low-fat products enriched in dietary fiber. Their incorporation, after adjustment, into the global diet may contribute to nutrition security, the sustainability of the coffee sector, and human health. [ABSTRACT FROM AUTHOR]

Coffee silverskin is a byproduct of the coffee roasting process contributing to organic waste burdens in urban areas. Silverskin is a potential source of dietary fiber, protein, carbohydrates, caffeine as well as vitamins and minerals. However, phytosterols present in the plant are susceptible to thermal oxidation resulting in the formation of phytosterol oxidation products (POPs) in the silverskin during roasting. In collaboration with a small roastery, the formation of POPs in three coffee varieties with roasting time was monitored by GC‐MS. The objective was to evaluate the safety and potential benefits of incorporating coffee silverskin into value‐added products. The qualitative profile of POPs in the silverskin from the three varieties was similar. Average total POPs were 0.32 g POPs/kg silverskin. POPs from the dominant plant sterol, sitosterol, were present at the highest concentrations. Caffeine, total antioxidant capacity, and total flavonoids were measured in the silverskin of the three coffees. Average values were 1.3 g caffeine/100 g silverskin, TEAC of 11 mmol Trolox/kg silverskin, and 1.94 to 8.60 mg catechin equivalent (CE)/g silverskin, respectively. An analysis of the impact of consuming teas and baked goods containing silverskin was also performed. Using published formulations, a tea or cookie containing silverskin would contribute approximately 1 and 0.3 mg POP per day, respectively. Consumption of these products would not substantially increase dietary exposure to POPs, while increasing fiber and antioxidants while reducing organic waste. Practical Application: Coffee silverskin has been studied as a possible source of fiber, antioxidants, and caffeine when incorporated in snack foods and used to make teas. To assess possible concerns about increasing dietary oxidized phytosterols, the formation of phytosterol oxidation products (POPs) was investigated in the silverskin fraction during the roasting process in three coffee varieties. In addition, caffeine, antioxidant capacity, and total flavonoids were determined. We found that silverskin can be safely used for value‐added products including caffeinated teas, cookies, and bars with minimal impact on dietary POP exposures. [ABSTRACT FROM AUTHOR]

A few million cubic tons of waste are generated annually as a result of coffee processing. As a beverage, coffee in itself is a rich source of melanoidins, phenolic compounds, and other phytonutrients which confer a wide range of health benefits. These wastes generated every year are usually discarded as landfill mass, mixed with animal fodder, or incinerated. Coffee wastes, due to their high content of tannins and caffeine, can degrade the soil quality and induce carcinogenicity when mixed with animal fodder. This review aims to identify the potential of coffee silver skin and spent coffee grounds, both generated as a result of the roasting process and instantization processes. Coffee husk and coffee flour are also well-known for their excellent bioactive roles. The proximate composition of coffee silverskin indicates a rich dietary fibre source and finds wide applications in bakery and other allied food products. This process could generate a value-added product and alleviate the disposing quality of remnant spent coffee grounds. Companies are exploring novel ideas of producing coffee flour obtained from drying and milling of coffee cherries for applications in day-to-day food products. Coffee and coffee waste combined with its high concentration of fibre, colorant pigments, and antioxidant compounds, has immense potential as a functional ingredient in food systems and needs to be explored further for its better utilization. [ABSTRACT FROM AUTHOR]

Probiotic dairy products must contain a certain level of live probiotic microorganisms at the time of consumption. The number of live microorganisms in kefir culture, which is a mixture of different microorganisms, may change during storage due to various factors. In this study, the effects of adding a novel ingredient coffee bean membrane (CSS-coffee silverskin), on the viability of microorganisms contained in kefir culture were investigated. For this purpose, CSS obtained from 2 different coffee varieties (Arabica and Robusta) was added to kefir samples at 3 different concentrations (0.5, 0.75 and 1.0 %) at the beginning of fermentation. It was observed that especially the addition of CSS belonging to the Robusta variety significantly increased the viability of lactic acid bacteria (lactobacilli and lactococci) which accounted for 88-94.10 % and 82.37-92.44 % respectively. During the storage period of 28 days at 4 °C; it could be observed that kefir enrichment with CSS of both coffee varieties increased the viability of lactobacilli and lactococci after in-vitro digestion, depending on the rate of supplementation. Number of yeasts was decreased during the storage. [ABSTRACT FROM AUTHOR]

Coffee by-products contain bioactive compounds that have been shown to have the capacity to modulate human metabolism. The goal of this study was to investigate the effects of the main bioactive compounds in coffee by-products and two aqueous extracts from the coffee husk and silverskin on the activation of fibroblast growth factor 21 (FGF21) signaling and the subsequent regulation of mitochondrial bioenergetics and lipid and glucose metabolism. HepG2 cells treated with palmitic acid (PA) were used in a non-alcoholic fatty liver disease (NAFLD) cell model. The bioactive compounds from coffee by-products (50 μmol L−1) and the aqueous extracts from the coffee silverskin and coffee husk (100 μg mL−1) increased ERK1/2 phosphorylation and the secretion of FGF21 (1.3 to 1.9-fold). Coffee by-products' bioactive compounds counteracted inflammation and PA-triggered lipotoxicity. Oxidative stress markers (ROS, mitochondrial superoxide, and NADPH oxidase) and the activity of antioxidant enzymes (superoxide dismutase and catalase) were modulated through the activation of Nrf2 signaling. Mitochondrial bioenergetics were regulated by enhancing respiration and ATP production via PGC-1α, and the expression of oxidative phosphorylation complexes increased. Coffee by-products' bioactive compounds decreased lipid accumulation (23–41%) and fatty acid synthase activity (32–65%) and triggered carnitine palmitoyltransferase-1 activity (1.3 to 1.7-fold) by activating AMPK and SREBP-1c pathways. The GLUT2 expression and glucose uptake were increased (58–111%), followed by a promoted glucokinase activity (55–122%), while glucose production and phosphoenolpyruvate carboxykinase activity were reduced due to IRS-1/Akt1 regulation. The bioactive compounds from coffee by-products, primarily chlorogenic and protocatechuic acids, could regulate hepatic mitochondrial function and lipid and glucose metabolism by activating FGF21 and related signaling cascades.

Coffee, as one of the most consumed beverages, generates a wide variety of waste materials that can be used as biofuels and bio-products. Conventional pyrolysis can be used in rural areas, improving the circular bioeconomy of these places. In this work, the characterization and slow pyrolysis of specialty coffee residues, coffee silverskin (CSS), and spent coffee (SC) were conducted at temperatures from 300 to 600 °C. Physico-chemical and thermal analysis were carried out. In addition, the quantification of individual compounds as acetic, formic, and levulinic acids, caffeine, and other minor compounds was performed. The results indicate the differences between both waste materials in the obtained pyrolysis fractions. The biochar fraction for SC is lower at all temperatures and the liquid fraction higher, reaching maximum values of 62 wt.% in the liquid at 600 °C compared to 47% in CSS. The higher yield in the liquid fraction of SC corresponds to the higher contents of hemicellulose and extractives and the lower ash content. The calculated calorific value for the pyrolysis solid fractions reaches 21.93 MJ/kg in CSS and 26.45 MJ/kg in SC. Finally, biorefinery options of major components of the liquid fraction were also presented.

Upcycling is a modern trend in the cosmetic sector, focusing on by-products reuse and waste reduction. Consumers are more aware of the origin of cosmetic products and their environmental impact, promoting the upcycling phenomenon. Converting these raw materials into products of higher quality or value contributes to the final product’s sustainability. In fact, several agri-food by-products that are typically discarded have generated great interest, due to their value-added compounds with high functionality and/or bioactivity. Coffee is well known as a cosmetic ingredient, particularly due to the presence of phenolic compounds, such as chlorogenic acids, and caffeine. Caffeine is widely used in cosmetic formulations due to its photoprotector and anti-aging properties, as well as lipolytic action in cellulitis, and hair regrowth. Chlorogenic acids are powerful antioxidants and exhibit anti-aging and photoprotector abilities. Coffee by-products, such as coffee beans, possess these bioactive compounds and other chemical characteristics that can provide functional properties in cosmetic formulations. Coffee silverskin and spent coffee grounds are high-volume by-products of the coffee industry. Their use has been explored in different cosmetic formulations demonstrating safety, stability, acceptability as well as skin improvement, thus supporting their valorization as natural and sustainable new ingredients in skincare products.

Recovery of agro and food-industrial waste and their valorisation via green technologies can help to outline new concepts of industrial strategies. In this contest, a fat enriched of added-value components was extracted from coffee silverskin by applying a supercritical fluid extraction technique (sc-CO2). An appropriate modulation of process parameters like temperature (T = 35, 50, 60 °C) and pressure (p = 200–300 bar) influences the fat yield and the chemical composition, opening the way for targeted extraction. The extraction time, the organic solvent use and the energy consume were reduced compared to Soxhlet. Moreover, a mathematical model was constructed based on the experimental data collected, employed apparatus, and physico-chemical characteristics of biomass, pointing to a possible industrial scale-up. The experimental results are accompanied by a preliminary cost of manufacturing (COM), highlighting how the high investment for the apparatus is compensated by several benefits. [ABSTRACT FROM AUTHOR]

Coffee silverskin (CSS) is a coffee by-product obtained during the coffee roasting process and a potential source of proteins (14–19% protein content). In this study, conventional extraction (CE) and novel extraction methods were investigated for protein extraction from CSS. Optimum extraction pH and concentration for conventional acid and alkali extraction were studied. In addition, ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), which have been widely recognised as efficient and economic novel extraction techniques, were employed to enhance the protein extraction from CSS using alkaline and acid extraction. Among the extraction techniques studied, MAE was found to generate the highest yield of protein recovery, 43.53% of recovery with an average molecular weight of 6.64 kDa. Comparing with the conventional sequential extraction using NaOH followed by HCl at two different concentrations (0.2 M and 0.6 M), the recovery yields were significantly increased by 2.8-fold and 2.3-fold by applying UAE, and by 5.8-fold and 7-fold by applying MAE. The present work shows that UAE and MAE have potential to be rapid and effective tools for protein extraction from coffee silverskin. In this study, extracted proteins and raw material were characterised considering the molecular weight and the amino acid profile as well as its nutritional composition and its mineral contents. [ABSTRACT FROM AUTHOR]

Although coffee silverskin (CS) has recently been used as a food ingredient, no knowledge has been reported on the effects of species or different post-harvest treatments on its chemical composition. Therefore, the fibre, volatile compounds, phenolic acid content, and antioxidant capacity of CS samples obtained at three roasting intensities (light, medium, and dark) from the Coffea arabica and C. canephora species, each subjected to a washing or a sun-drying (“natural”) post-harvest treatment, were studied. Obtained results showed that the chemical composition of CS is due to species, roasting, post-harvest treatment, and interaction. In particular, natural Arabica CS showed the highest content of volatile compounds of Maillard and varietal origin, whereas washed Arabica CS showed the highest content of soluble dietary fibre and chlorogenic derivatives. Pyrroles, sulphur compounds, and pyridines contents were higher in Canephora CS than in Arabica CS. The dark-roasted washed Arabica CS showed the highest content of 5-O- and 3-O-caffeoylquinic acids, while the natural Arabica CS highlighted the highest antioxidant capacity. The effect of post-harvest treatments seemed to be emphasised in Arabica CS, independent of roasting, which did not significantly affect the antioxidant capacity of CS from either species.

Coffee is a widely enjoyed beverage and one of the world's most traded commodities. However, it also generates large amounts of bio-based waste including coffee silverskin (CS) and spent coffee grounds (SCG). Both SCG and CS contain oils, polyphenols, and caffeine among other substances, showing potential for valorization. However, most of the SCG and CS generated by the coffee industry is discarded as waste. SCG and CS are lignocellulosic materials that show potential for the production of biocomposites. Because of their hydrophilic character, chemical modification of these wastes is often necessary before compounding with polymers. Oil extracted from SCG can be cultured with bacteria for producing biopolymers. The use of SCG and CS in nanoform has been seldom explored, although CS in particular shows potential as a source of nanocellulose. Utilization of SCG and CS in packaging development could thus be beneficial in the context of the circular economy. Therefore, this review summarizes recent research on the development of packaging materials using SCG and CS. The composition and characteristics of both wastes are presented, and the production of biopolymers and composites using these materials is discussed. [ABSTRACT FROM AUTHOR]