Search Results (339)

Coffee silverskin (CS), a by-product generated during coffee roasting, contains high levels of xylan hemicellulose and protein, making it a promising substrate for functional ingredient production. This study developed an integrated bioprocess to simultaneously produce bioactive peptides and xylooligosaccharides (CS-XOS) from CS. Conventional alkaline extraction (CAE) under optimized conditions (1.0 M NaOH, 90 °C, 30 min) yielded 80.64 mg of protein per gram of CS and rendered the solid residue suitable for XOS production. Enzymatic hydrolysis of the extracted protein using protease_SE5 generated low-molecular-weight peptides (0.302 ± 0.01 mg/mL), including FLGY, FYDTYY, and FDYGKY. These peptides were non-toxic, exhibited in vitro antioxidant activity (0–50%), and showed ACE-inhibitory activities of 60%, 26%, and 79%, and DPP-IV-inhibitory activities of 19%, 18%, and 0%, respectively. Concurrently, the alkaline-treated CS solid residue (ACSS) was hydrolyzed using recombinant endo-xylanase, yielding 52.5 ± 0.08 mg of CS-XOS per gram of ACSS. The CS-XOS exhibited prebiotic effects by enhancing the growth of probiotic lactic acid bacteria (μ_max 0.100–0.122 h⁻¹), comparable to commercial XOS. This integrated bioprocess eliminates the need for separate processing lines, enhances resource efficiency, and provides a sustainable strategy for valorizing agro-industrial waste. The co-produced peptides and CS-XOS offer significant potential as functional food ingredients and nutraceuticals. Full article

Background/Objectives: Most snakebite incidents in Latin America are caused by species of the Bothrops genus. Their venom induces severe local effects, against which antivenom therapy has limited efficacy. Metabolites derived from Coffea arabica have demonstrated anti-inflammatory and anticoagulant properties, suggesting their potential as therapeutic agents to inhibit the local effects induced by B. asper venom. Methods: Three enzymatic assays were performed: inhibition of the procoagulant and amidolytic activities of snake venom serine proteinases (SVSPs); inhibition of the proteolytic activity of snake venom metalloproteinases (SVMPs); and inhibition of the catalytic activity of snake venom phospholipases A₂ (PLA_2s). Additionally, molecular docking studies were conducted to propose potential inhibitory mechanisms of the metabolites chlorogenic acid, caffeine, and caffeic acid. Results: Green and roasted coffee extracts partially inhibited the enzymatic activity of SVSPs and SVMPs. Notably, the green coffee extract, at a 1:20 ratio, effectively inhibited PLA₂ activity. Among the individual metabolites tested, partial inhibition of SVSP and PLA₂ activities was observed, whereas no significant inhibition of SVMP proteolytic activity was detected. Chlorogenic acid was the most effective metabolite, significantly prolonging plasma coagulation time and achieving up to 82% inhibition at a concentration of 62.5 μM. Molecular docking analysis revealed interactions between chlorogenic acid and key active site residues of SVSP and PLA₂ enzymes from B. asper venom. Conclusions: The roasted coffee extract demonstrated the highest inhibitory effect on venom toxins, potentially due to the formation of bioactive compounds during the Maillard reaction. Molecular modeling suggests that the tested inhibitors may bind to and occupy the substrate-binding clefts of the target enzymes. These findings support further in vivo research to explore the use of plant-derived polyphenols as adjuvant therapies in the treatment of snakebite envenoming. Full article

Açaí (Euterpe oleracea) seeds account for up to 95% of the fruit’s weight and are commonly discarded during pulp processing. Roasted açaí seed extract (RASE) has recently emerged as a caffeine-free coffee substitute, although its composition and functionality remain underexplored. This study characterized commercial açaí seed powder and evaluated the effect of temperature on the recovery of total phenolic content (TPC) in the aqueous extract using a Central Composite Rotatable Design (CCRD). An intermediate extraction condition (6.0 ± 0.5 g 100 mL⁻¹ at 100 °C) was selected, resulting in 21.78 mg GAE/g TPC, 36.23 mg QE/g total flavonoids, and notable antioxidant capacity (FRAP: 183.33 µmol TE/g; DPPH: 23.06 mg TE/g; ABTS: 51.63 mg TE/g; ORAC: 31.46 µmol TE/g). Proton Nuclear Magnetic Resonance (¹H NMR) analysis suggested the presence of amino acids, carbohydrates, and organic acids. During in vitro digestion, TPC decreased from 54.31 to 17.48 mg GAE 100 mL⁻¹ when RASE was combined with goat milk. However, higher bioaccessibility was observed with skimmed (33%) and semi-skimmed (35%) cow milk. These findings highlight RASE as a phenolic-rich, antioxidant beverage with functional stability when prepared with boiling water. This is the first study to report the phytochemical profile of RASE and its interactions with different milk types, supporting its potential as a coffee alternative. Full article

Roasted coffee silverskin (RCSS) is a by-product of coffee production characterized by its content of phenolic compounds, both free and bound to macromolecules. In this study, RCSS was fermented to release these compounds and consequently increase its value as a functional food ingredient. Fermentation was carried out using yeast, acetic acid bacteria, and lactic acid bacteria, either as single strains or as a designed microbial consortium. The latter included Saccharomycodes ludwigii, Gluconobacter oxydans, and Levilactobacillus brevis, mimicking a symbiotic culture of bacteria and yeast commonly used in kombucha fermentation (SCOBY). This symbiotic microbial culture consortium demonstrated notable efficacy, significantly enhancing the total phenolic content in RCSS, with values reaching 14.15 mg GAE/g as determined by the Folin–Ciocalteu assay and 7.12 mg GAE/g according to the Fast Blue BB method. Antioxidant capacity improved by approximately 28% (ABTS) and 20% (DPPH). Moreover, the fermented RCSS supported the viability of probiotic strains (Saccharomyces boulardii SB01 and Levilactobacillus brevis ŁOCK 1152) under simulated intestinal conditions. These results suggest that RCSS, particularly after fermentation with a full symbiotic microbial culture consortium, has strong potential as a clean label, zero-waste functional food ingredient. Full article

In the energy sector and in other types of industries (cement, iron/steel, chemical and petrochemical), highly roasted coffee ground residue can be used as a source material for producing bioadsorbents suitable for CO₂ capture. In this study, a bioadsorbent was produced in a two-step process involving biowaste carbonization and biocarbon activation within a KOH solution. The physicochemical properties of the bioadsorbent were assessed using LECO, TG, SEM, BET and FT-IR methods. Investigating the CO₂, O₂ and N₂ equilibrium adsorption capacity using an IGA analyzer allowed us to calculate CO₂ selectivity factors. We assessed the influence of exhaust gas carbon dioxide concentration (16%, 30%, 81.5% and 100% vol.) and adsorption step temperature (25 °C, 50 °C and 75 °C) on the CO₂ adsorption capacity of the bioadsorbent. We also investigated its stability and regenerability in multi-step adsorption–desorption using a TG-Vacuum system, simulating the VSA process and applying different pressures in the regeneration step (30, 60 and 100 mbar_abs). The tests conducted assessed the possibility of using a produced bioadsorbent for capturing CO₂ using the VSA technique. Full article

With the development of various new types of instrumental aroma sensing technologies, there is a need for methodologies that help developers and users evaluate the performance of the different devices. This study introduces a simple method that uses standard coffee beverages, reproducible worldwide, thus allowing users to compare aroma sensing devices and technologies globally. Eight different variations of commercial coffee capsules were used to brew espresso coffees (40 mL), consisting of either Arabica coffee or a blend of Robusta and Arabica coffee, covering a wide range of sensory attributes. The AlphaMOS Astree electronic tongue (equipped with sensors based on chemically modified field-effect transistor technology) and the AlphaMOS Heracles NEO and the Volatile Scout3 electronic noses (both using separation technology based on gas chromatography) were used to describe the taste and odor profiles of the freshly brewed coffee samples and also to compare them to the various sensory characteristics declared on the original packaging, such as intensity, roasting, acidity, bitterness, and body. Linear discriminant analysis (LDA) results showed that these technologies were able to classify the samples similarly to the pattern of the coffees based on the human sensory characteristics. In general, the arrangement of the different coffee types in the LDA results—i.e., the similarities and dissimilarities in the types based on their taste or smell—was the same in the case of the Astree electronic tongue and the Heracles electronic nose, while slightly different arrangements were found for the Scout3 electronic nose. The results of the Astree electronic tongue and those of the Heracles electronic nose showed the taste and smell profiles of the decaffeinated coffees to be different from their caffeinated counterparts. The Heracles and Scout3 electronic noses provided high accuracies in classifying the samples based on their odor into the sensory classes presented on the coffee capsules’ packaging. Despite the technological differences in the investigated devices, the introduced coffee test could assess the similarities in the taste and odor profiling capacities of the aroma fingerprinting technologies. Since the coffee capsules used for the test can be purchased all over the world in the same quality, these coffees can be used as global standard samples during the comparison of different devices applying different measurement technologies. The test can be used to evaluate instrumentational and data analytical developments worldwide and to assess the potential of novel, cost-effective, accurate, and rapid solutions for quality assessments in the food and beverage industry. Full article

The main diterpenes found in coffee, kahweol and cafestol, possess anti-inflammatory, anti-diabetic, and anticancer properties but are also reported to cause hypercholesterolemic effects. Their concentrations are known to be variable in coffee. This review aimed to discuss the concentrations of kahweol and cafestol from green coffee beans to brewed coffee. The results showed that the average concentrations of kahweol and cafestol in Arabica green beans were higher than in roasted and brewed coffee. The decrease in kahweol from green beans to roasted beans was 14.83%. In brewed coffee, kahweol was reduced by 90.26% and cafestol by 88.28%, compared to green beans. The changes in kahweol and cafestol levels were found to be influenced by various factors, including roasting methods and brewing techniques. The ratio of kahweol to cafestol in Arabica green beans was 1.7; in green coffee oil and roasted coffee oil, 1.2; in roasted beans, 1.3; and in brewed coffee, 1.1. In addition to their health-related functional properties, kahweol and cafestol concentrations and their ratio are suggested to be relevant markers in distinguishing between coffee species at various processing stages. Full article

With the growing interest in natural and health-supporting foods, oak acorns (Quercus robur) are gaining renewed attention for their nutritional and antioxidant potential. This study explored how different processing methods affect bioactive compounds in three acorn-based products: raw acorn flour, roasted “coffee,” and washed-and-roasted “super coffee.” Extracts were obtained using methanol, acetone, and hexane to evaluate total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity via ABTS, DPPH, CUPRAC, FRAP, and TRP assays. Methanol proved to be the most effective solvent, extracting up to 66.53 mg GAE/g dw of phenolics in raw flour and 76.50 mg GAE/g dw in roasted “coffee,” reflecting a 15% increase in TPC after thermal treatment. However, the same treatment resulted in a 17% decrease in flavonoid content, from 181.5 mg RE/g dw in raw flour to 150.67 mg RE/g dw in “super coffee.” Antioxidant activity followed a similar pattern, with methanol extracts showing the highest values, up to 584 mg TE/g dw in the CUPRAC assay and 126.7 mg TE/g dw in ABTS. Safety was also assessed through the quantification of 16 priority polycyclic aromatic hydrocarbons (PAHs). The total PAH levels in the roasted “coffee” and “super coffee” samples were 222 ng/g dw and 290 ng/g dw, respectively. Importantly, PAH4 compounds, used as key safety indicators in EU regulations, were present in low concentrations, primarily as benzo[a]anthracene (34.3–39.8 ng/g), and none exceeded the maximum limits established for cocoa-based products. Benzo[a]pyrene, a major carcinogen, was not detected. The results confirm that acorns of Quercus robur, especially in their native flour form, are rich in antioxidants, naturally gluten-free, and safe when thermally processed, making them a strong candidate for use in functional foods. Full article

Sustainable alternatives to peat in horticultural substrates are increasingly sought. This study assessed the use of coffee silverskin (CS), a byproduct of coffee roasting, as a substrate component for rooting and growing ornamental plants—Buddleja, Lythrum, and Veronica. Plants were cultivated in peat-based substrates with 0%, 25%, 50%, and 75% CS addition. In order to determine the effect of substrate modification with CS, the following parameters were analyzed: rooting efficiency, plant growth, pigment content, physiological indices (SPAD, Fv/Fm, NFI), and substrate properties. A 25% CS addition supported high rooting success (94.4% on average) without negatively affecting root or shoot traits, and even improved flowering earliness. At 50% CS, Buddleja showed moderate tolerance, while Lythrum and Veronica performed poorly. The substrate with 75% CS addition significantly reduced rooting and growth across all species. Elevated pH and electrical conductivity in high-CS substrates likely contributed to plant stress. Physiological indicators confirmed minimal stress at 25% CS, but increased stress response at 75%. Overall, CS can replace up to 25% of peat in substrates without compromising plant performance, offering a sustainable alternative in nursery production. However, higher CS levels require structural or chemical adjustments to reduce compaction and stress effects. Further research is needed to improve CS-based substrate formulations for broader horticultural use. Full article

The functional properties of coffee are mainly attributed to bioactive compounds, primarily caffeine and polyphenols. Their quantitative and qualitative profile depends on many factors, including the roasting process. The study aimed to assess the effect of different roasting conditions on the caffeine content and polyphenol composition of the Ethiopian variety Coffea arabica L. (from two regions: Sidama and Jimma). In total, 21 bioactive compounds were identified, including caffeine, 14 phenolic acids, 3 flavonoid glycosides, and 3 flavonoids. It was found that chlorogenic acid had the highest concentration of all phenolic compounds in the Jimma and Sidama varieties, regardless of the degree of roasting. Studies have shown that the initial stage of coffee roasting (light roast) affects chlorogenic acid content—its level increases compared to green coffee, but then decreases in subsequent roasting stages (medium and dark roast). In contrast, the concentration of caffeic acid decreases during the light roast stage, while it increases during the medium and dark roast stages. The Sidama variety contains more caffeine than the Jimma variety. Full article

Currently, there is an ever-increasing demand for organic food from consumers who are convinced that it is healthier and more nutritious. The purpose of our research was to carry out an evaluation of the nutritional and sensory characteristics of organic and conventional hazelnuts of Tonda Gentile Romana cv. To this end, volatile composition, total phenolics, antioxidant capacity, and sensory profile of organic and conventional hazelnuts were identified. In comparison to conventional hazelnuts, organic hazelnuts had a greater amount of total phenols and antioxidants. Furthermore, organic hazelnuts had a different sensory profile, with more crunchiness (6.722 vs. 4.056 for raw and 8.389 vs. 4.667 for roasted) and sweetness (7.667 vs. 4.867 for raw and 7.089 vs. 3.889 for roasted), accompanied by distinct hazelnut, almond, walnut, popcorn, coffee, and roasty notes, present in much higher amounts than conventional hazelnuts. One of our key findings is that organic hazelnuts have a higher nutritional value due to their higher antioxidant capacity. Promoting organic hazelnuts helps to encourage consumers to use these products, which have a high nutritional value, thus contributing to public health. Full article

The objective of this study was to obtain and evaluate a coffee aroma extract/oil with sensorial attributes close to the original brew of Greek coffee for use in an instant Greek coffee powder. The oil was obtained directly from commercial Greek coffee by solid-liquid extraction using hexane as a solvent and treated with a series of hexane-ethanol mixtures (0:10, 1:4, 1:9) to remove the intense roasted flavor of the crude coffee oil obtained by hexane; the de-oiled coffee was used for the recovery of water-soluble compounds, and the produced water extract was freeze-dried. The aromatic volatiles of the coffee oil samples were analyzed by using a purge-and-trap device coupled to GC-MS, as well as sensory analysis. The instant Greek coffee powder was produced by mixing the freeze-dried base (74.4%) with the extract derived after treatment of the crude oil with hexane-ethanol mixture 1:4 (18.2%) and foaming agent (7.4%). Two different materials were studied as bases: instant coffee (F3_Gr-D) and ground Greek coffee (reference sample, C_Gr). The shelf-life stability of the produced powders was examined at three storage temperatures (25, 45, 60 °C). Instrumental analysis (purge-and-trap GC-MS) of aroma and sensory analysis (aroma, taste, staling, total sensory quality on a 1–9 hedonic scale) was conducted. Aroma loss (furfuryl alcohol, furfural, dimethyl pyrazines, ethyl methyl pyrazines) and scores for sensory attributes during storage were modeled using 1st and 0-order reaction kinetics, respectively. The storage temperature effect was expressed by the Arrhenius model (activation energy E_a). According to the results, the developed instant coffee powder presented satisfactorily the aroma characteristics of regular Greek coffee. The shelf life for the instant Greek coffee powder was estimated as 80 days (air packed) (based on 20% retention of furfuryl alcohol that was the most abundant aromatic volatile of Greek coffee aroma, ground as well as extract oil). Full article

Novel methods of coffee processing, including animal-assisted fermentation, are gaining popularity—among them, elephant dung coffee stands out for its rarity and high price, making it a likely target for adulteration. This study aims to discover candidate biomarkers for elephant coffee by comparing the chemical composition, antioxidant activity, and volatile profiles of Arabica coffee processed by three methods: conventional, civet-derived, and elephant-derived (all originated from Southeast Asia, medium roast). Analytical methods included HPLC-UV and GC-SPME-MS, along with in vitro antioxidant assays (DPPH, ORAC, ABTS, total phenolics, and total flavonoids). Principal Component Analysis (PCA) was used to evaluate differences between the samples. While elephant coffee showed lower caffeine (0.93%) and antioxidant capacity across all assays, it was richer in selected volatile compounds, such as pyrazines (e.g., 3-ethyl-2,5-dimethylpyrazine; 3.73% RPA), 2- and 3-methybutanal (1.18 and 0.19% RPA), and furfuryl acetate (18.00% RPA; p < 0.05). These changes are likely to be due to fermentation in the gastrointestinal tract. Despite differences, no definitive biomarker of elephant coffee was found, suggesting that discrimination from other coffee samples may not be as simple as previous studies indicated. More studies with a higher number of samples that employ an extensive analytical approach (e.g., omics or NMR) to thoroughly analyze the phytochemical profile of coffee beans before and after digestion by the elephant are needed. Full article

South American coffee producers face growing challenges due to external trade dependencies and climate-induced disruptions. This study investigates the role of export market diversification as a sustainability strategy for four major regional exporters of roasted non-decaffeinated coffee: Brazil, Colombia, Peru, and Ecuador. A quantitative and comparative methodology was applied over a ten-year period using the Herfindahl–Hirschman Index (HHI) to evaluate export market concentration and the Revealed Comparative Advantage (RCA) Index—including its normalized variant—to assess international competitiveness by destination. The results reveal substantial disparities: Brazil and Colombia exhibit moderate to high diversification and relative competitiveness in select markets, while Peru and Ecuador remain dependent on a few strategic buyers, with limited or declining comparative advantages. The findings emphasize that sustained export performance in the coffee sector requires not only a broader destination portfolio but also improved positioning through trade agreements, infrastructure development, and climate-resilient innovation. This study concludes with a strategic proposal based on three pillars—commercial, logistical, and technological—to support structural transformation and enhance the long-term sustainability of the coffee trade in South America. Full article

Coffee and coffee by-products, such as coffee cherries, coffee flowers, coffee leaves, green beans, roasted coffee, instant coffee, spent coffee grounds, and silverskin, contain a complex mixture of bioactive compounds that may exhibit both genotoxic and antimutagenic effects. This article evaluates in vitro studies on the genotoxic potential of coffee and coffee by-products, with a focus on different preparation methods, roasting processes, and key chemical constituents. Furthermore, given the growing interest in utilizing coffee by-products for novel food applications, this review sought to identify knowledge gaps regarding their safety. The impact of metabolic activation, particularly the role of enzymatic detoxification and bioactivation, was examined to better understand the effects on genetic material. The findings suggest that while certain compounds in coffee can induce DNA damage under specific conditions, the overall evidence does not indicate a significant genotoxic risk to consumers. However, further studies, particularly in vivo and human studies, appear necessary to ensure the requirements of novel food applications for some coffee by-products. Full article