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A wet coffee processing plant is an agro-industry that generates huge volumes of medium to highstrength wastewater that needs proper treatment before being released into the environment. Low-income countries must adopt an integrated, easily adaptable, and eco-friendly system to treat such effluent. The objective of this study was to treat wet coffee processing wastewater (WCPWW) using pretreatment units (aeration and sedimentation) and a macrosom scale HSSFCW cells, each 1.80 m x 0.60 m x 0.50 m (length x width x depth; area = 1.08 m²) planted with emergent wetland plants. Three HSSFCW cells whose bottom and sides get lined with plastic membranes were filled with gravel and planted with the wetland plants (Cyperus alternifolius, Vetiveria zizanioides, and Pennisetum purpureum), while the fourth cell was left unplanted (control). The HSSFCW cells were fed with different tap water and WCPWW mix ratios at the 7 d interval until the plants adapted to the new environment. After pretreated and pH adjusted to 6.10, the WCPWW was allowed to enter the HSSFCW cells from an equalization tank via plastic pipes equipped with control valves. Triplicate samples were collected from the inlets and outlets of each treatment unit and analyzed in the laboratory according to standard methods. The results revealed that sedimentation and aeration units achieved 51.80 and 19.80 for BOD5, 61.60 and 22.10 for COD, -46.70 and 26.50 for NO3--N, 17.0 and 38.50 for NH3-N, 19.10 and 8.10 for PO43--P 76.10 and 19.60 for TSS, 50.90 and 27.50 for TDS and -23.30 and 27.70 for EC % removals, respectively. HSSFCW2, (planted with V. zizanioides) and HSSFCW3 (control) cells achieved 78.50 and 61.70 for BOD5, 80.10 and 69.10 for COD, 70.20 and 43.20 for NO3--N, 50.10 and 29.0 for NH3--N, 79.60 and 57.40 for PO43--P, 72.40 and 65.80 for TSS and 51.20 and 42.80 for TDS, and 31.10 and 22.30 for EC % removal respectively. The wetland cell, HSSFCW2 achieved a better % removal for organic matter, solids, and nutrients. In conclusion, the integrated system is a good option for treating WCPWW. The treatment system must integrate more units to achieve effluent compliance with discharge limits. [ABSTRACT FROM AUTHOR]

This study investigated a novel continuous cold brewing method accomplished through a combined countercurrent single-screw extraction process and mechanical expression approach. The effects of four processing parameters (grind size (GS), motor rotation speed (RPM), press cone piston pressure (PCPP), and dry unbrewed coffee grounds feed rate (GFR)) on the particle size of coffee grounds, the mass balance of coffee grounds and water/brew in the brewer, and the physicochemical quality (total dissolved solids (TDS), extraction yield (EY), titratable acidity (TA), total polyphenols (TPP), pH, caffeine and 5-caffeoylquinic (5-CQA) concentration) of the brew were evaluated. The processing parameters significantly affected the mechanical interactions between the coffee grounds and brewer, resulting in changes in the packing density of coffee grounds, the moisture content of the spent coffee grounds, the extent of grind size reduction, and the amount of fines in the brew. These changes affected the physicochemical quality of the resultant brew leading to significant differences in TA, TPP, and 5-CQA, which were positively correlated with TDS. • Achieved cold brew coffee extraction with prototype brewer under 16 treatments. • General linear models used to elucidate physical and physicohemical phenomena. • Brew concentration influenced by particle size reduction, agitation, and packing density. • Hydration and attrition contributed to changes in coffee particle size. • Mechanical expression modified brew concentration but not composition. [ABSTRACT FROM AUTHOR]

This study quantified, for the first time, 2-isopropylmalic and 3-isopropylmalic acids, in green, roasted and espresso coffee by UHPLC-MS/MS. Moreover, it reports the influence of postharvest processing methods (natural, washed and honey) on their content. New extraction techniques were developed and validated from three coffee matrices (green, roasted and espresso). Honey coffee exhibited levels substantially higher of 2-isopropylmalic acid than those processed by natural and washed methods (p < 0.05). Specifically, 2-isopropylmalic acid levels in honey green, roasted and espresso coffee samples were 48.24 ± 7.31 ng/g, 168.8 ± 10.88 ng/g and 177.5 ± 9.49 ng/g, respectively. This research highlights the significant impact of processing methods on the chemical profile of coffee and introduces 2-isopropylmalic and 3-isopropylmalic acids as potential quality indicators. Moreover, it suggests that the fermentation stage during processing may play a crucial role in their formation, laying the foundation for optimizing coffee processing to enhance quality. [Display omitted] • First quantification of 2-IPMA and 3-IPMA in coffee. • Honey processing boosts 2-IPMA levels. • Novel extraction methods for malic acid derivatives in coffee. • Link between processing methods and chemical profiles. • Potential new indicators of coffee quality. [ABSTRACT FROM AUTHOR]

Coffee is the second most consumed product worldwide, cultivated in over 70 countries with an average annual production of 165–170 million bags. Despite the coffee processing methods used, one common research question is about the fate of the wastes generated. Several studies highlight the need for coffee processing waste management, following global calls for climate-smart industrial processing leveraging on reducing the carbon footprint. Various levels of success have been reported in the literature concerning waste transformation into added-value products. Coffee processing waste valorization has been highlighted, including biofuels, building materials, biodegradable containers, organic fertilizer, and value-added compounds production or extraction among others. This review explores opportunities for closing the loop in the coffee value chain concerning circular economy while contributing mainly to seven sustainable development goals. Individual techniques and management practices have been reviewed to propose a scheme for coffee processing waste valorization in a circular economy concept, focusing not only on covering the coffee plantations and processing plants' needs but also on establishing new potential synergies. Thermochemical and biological processes can potentially add further value to coffee waste by facilitating the extraction of high-value compounds. Interest in harnessing these compounds from coffee waste streams continues to grow, highlighting the potential for innovative waste valorization approaches. Despite the data available, gaps still remain in the quest to close the loop and achieve zero waste mainly due to the lack of relative frameworks, regulations, and robust upscaled implementations toward coffee value chain circularity. [Display omitted] • Wet processing is preferred due to improved control despite the high waste amounts. • Waste valorization pathways are proposed combining individual published practices. • An integrated coffee waste biorefinery could significantly promote sustainability. • Integrating circularity into coffee processing can transform countries' economies. • A coffee waste valorization scheme under circular context could promote synergies. [ABSTRACT FROM AUTHOR]

• Flower morphological traits can be used to differentiate Coffea spp. genotypes. • Among nine flower traits, four are explaining 70.8 % of the variation. • Floral trait evaluation was optimized by eliminating five of nine traits. • Some flower morphological traits of flowers in Coffea spp. are correlated. • Some C. canephora genotypes have flowers morphologically similar to C. arabica. The identification of key traits in optimization of phenotypic variability studies represents time savings in development of new cultivars. To attain this purpose, it was hypothesized that: 1) different coffee genotypes presented morphological variability in flower size and form, 2) various coffee flower size and form traits were correlated, 3) the exclusion of correlated flower morphological traits can facilitate future flower evaluations, without compromising the inference of phenotypic variability. A total of 36 Coffea canephora and the two C. arabica genotypes were studied. Nine floral traits were measured in 760 flowers. It was proven that the flower phenology can be used to differentiate Coffea spp. genotypes. Some genotypes of C. canephora , such as Beira Rio 8, Guarani, 8R, and Clementino, had the largest floral structures. On the other hand, the genotypes Z8, Verdim D, Ouro Negro 1, Tardio C, NV8, Ouro Negro 2, Bamburral, LB1, and Peneirão had the smallest floral structures. Among the nine evaluated floral traits, the five (petal length, anther length, stamen length, style length, and stigmatic lobe length) were strongly correlated with the traits of the greatest weight for data variability. The correlated traits had little contribution to the data variability, permitting that their exclusion had not compromised the inference of morphological flower variability in Coffea spp. genotypes. This suggested that studies aiming at differing the Coffea spp. genotypes based on floral structures may consider the four studied traits, tube length, tube diameter, corolla diameter, and the number of floral appendages (petals or stamens). The reduction of nine to these four traits can optimize time and efficiency in data collection. In the future works, the association of selected flower morphological traits with traits related to Coffea spp. production could additionally move ahead the process of coffee breeding programs. [Display omitted] [ABSTRACT FROM AUTHOR]

The characteristic flavor of Coffea arabica from Yunnan is largely attributed to the primary processing treatments through affecting the VOCs accumulation. Therefore, a rapid and comprehensive detection technique is needed to accurately recognize VOCs in green coffee beans with different pretreatment methods. Hence, we conducted volatile profiles and identified nine markers of three different primary processed green coffee beans from the major production areas in Yunnan with the combined of HS-SPME-GC-MS and PTR-TOF-MS. The relationships between the chemical composition and the content of VOCs in green coffee beans were elucidated. Among the markers, palmitic acid (F3), linoleic acid (F6), α -ethylidene phenylacetaldehyde (T4), and phytane (T8) contributed to the antioxidant activity of sun-exposed green coffee beans. In conclusion, the analytical technology presented here provided a general tool for an overall and rapid understanding of a detailed volatile profiles of green coffee beans in Yunnan. • Characterizing chemical classes in different primary processed green coffee beans. • Identified nine markers in different processed green coffee beans from three origins. • Confirmed the viability of rapid recognition of markers in green coffee beans. • Possible contributors of antioxidant activity were found in VOCs and markers. [ABSTRACT FROM AUTHOR]

In the coffee industry, the use of natural coffee extracts with differentiated attributes is desirable to drive new product development. This study evaluates the impact of ultrafiltration membrane processing on the sensory, metabolic, and physicochemical attributes of four commercially available coffee extracts: cold brew, lightly roasted, freeze concentrated and evaporated standard. The sensory analysis revealed an increase in acidity in the permeate across all extracts, with the most significant profile changes observed in the lightly roasted evaporated and evaporated extracts, accompanied by an enhancement of fruity and floral attributes. Furthermore, the permeate showed reduced total dissolved solids, while the caffeine concentration increased. Metabolomic analysis highlighted key coffee-related metabolites like cinnamic and coumaric acids, explaining observed variations due to their passage through the membrane. Our findings emphasize the potential of permeate as a coffee-based ingredient for ready-to-drink products development, providing a unique coffee experience with organoleptic profiles distinct from traditional beverages. [Display omitted] • UF process improves sensory and metabolic characteristics of coffee extracts. • 75 metabolites and 42 sensory attributes were altered between feed and permeate. • Permeate holds potential as an ingredient for developing ready-to-drink products. [ABSTRACT FROM AUTHOR]

The Anaerobic Digestion Model N o . 1 (ADM1) was applied in this study to simulate the anaerobic digestion (AD) of wastewaters from soluble coffee processing in sequential batch reactors. As these substrates present considerable levels of phenolic compounds, modifications were made to the basic structure of the ADM1. Additionally, the Luong inhibition model replaced the Monod model to describe the consumption of soluble organic matter. On the other hand, the removal of phenolic compounds was carried out using the Haldane model, appropriate when the inhibition by excess substrate is present, taking into account in this case the quantification of phenols and benzoic acid as total phenols. The new ADM1-based model was calibrated with experimental data from the AD of post hydrothermal wastewater (PHWW) of spent coffee grounds (SCG) and validated with experimental data of the AD of effluents produced during the soluble coffee processing. The simulation results demonstrated that the new model moderately described the removal of phenolic compounds (> 90 %), methane production (2.243 kg COD m −3 in calibration and 6.16 kg COD m −3 in validation), and the production and consumption of organic acids over time. However, in future research new metabolic pathways may be included in the model to improve its quality even more. • ADM1 was modified to simulate the anaerobic digestion of residues from soluble coffee processing. • Luong's inhibition kinetics was incorporated into the ADM1 to describe the substrate degradation. • The removal of phenolic compounds was described by the Haldane kinetic. • The model moderately described methane production and phenolic degradation. [ABSTRACT FROM AUTHOR]

The research was carried out to investigate wastewater discharge’s technical viability from wet coffee processing plant (WCPP) treatments with aeration and Cyperus ustulatus plant, Typha latifolia plant. The WCPP wastewater was conducted at various aeration days (5, 10, 15, 20 and 25 d) after being irrigated for 21 d in the constructed wetland with Cyperus ustulatus and Typha latifolia plant and without a plant. The highest value of total solids, chemical oxygen demand and biochemical oxygen demand increasing were 87.8%, 97.4% and, 98.1%, respectively, in 25 d aerated with Typha latifolia plant (P2) wetland. After 25 d of aeration with Cyperus ustulatus plant (P1) treated polluted water value of biological oxygen demand (97.8%), chemical oxygen demand (96.9%) and total solids (88.5%). The Typha latifolia (P2) with 25 d aerated WCPWW reduced 94.2% and 98.1% of NO3–N and PO4 ³, respectively. As a result, the aeration days were increased with the removal efficiency of pollutants discharged from wet coffee processing plant increased with a constructed wetland. It shows that aeration with constructed wetland treatment method was a low-cost, affordable, technically viable and eco-friendly treatment option for the wet coffee processing plant wastewater. [ABSTRACT FROM AUTHOR]

Coffee processing wastewater (CPW) is a highly polluted industrial wastewater that can be detrimental to the environment when it is discharged into a watercourse without treatment. The present study looks at the performance of a strong acid cation exchange resin and a strong base anion exchange on the removal of chemical oxygen demand (COD), colour, and ammoniacal nitrogen (NH3 –N) from CPW using batch experiment. The experiments were carried out with varying pH, resin dosage (g), contact time (min), temperature (°C), and shaking speed (rpm). It was observed that over 70% reduction of NH3 –N was achieved under optimal conditions by cation exchange resin, while more than 70% COD, 60% colour removal was attained by anion exchange resin. Langmuir, Freundlich, and Brunauer–Emmett–Teller isotherm models were applied to determine the COD, colour and NH3 –N removal behaviour from CPW using cationic and anionic resins. The findings revealed that the Langmuir equation was the best-described isotherm model for removing COD, colour and NH3 –N from CPW using both cationic and anionic resins. The kinetic study showed that the removal of COD, colour, and NH3 –N was well-fitted with the pseudo-second-order kinetic model. Furthermore, it was observed that the diffusion was the rate-controlling process. The determination of the thermodynamic properties analyses showed that the COD, colour and NH3 –N removal from CPW using cationic and anionic resins was spontaneous and endothermic. The study suggests that both ion exchangers could reduce the concentration of pollutants in the coffee processing waste water. [ABSTRACT FROM AUTHOR]

This study focused on enhancing the drying process of coffee by introducing an innovative device called as roto-aerated dryer. Traditional methods often result in prolonged drying times and undesirable degradation, prompting the exploration of alternative techniques. The research involves evaluating drying performance, establishing correlations between physical-chemical attributes and coffee quality, and determining optimal operating conditions to achieve a balance between drying efficiency and product quality. The Central Composite Design was employed, varying air velocity (v f), air temperature (T f), and solid feed rate (W s). The results demonstrated increased drying efficiency while preserving key quality parameters, including acidity, water activity, sugars, and organic acids. The desirability function identified the optimal levels of the operational variables as v f = 2.7 m·s−1, T f = 81.8 °C, and W s = 40 g·min−1. This study introduced an innovative approach to enhance the drying efficiency of coffee while ensuring exceptional product quality, providing valuable insights for the coffee industry. Coffee, one of the most important global commodities, undergoes ongoing enhancements in post-harvest processing to achieve exceptional quality, particularly in specialty coffee. Conventional methods face challenges related to processing time and the potential compromise of quality. These challenges are effectively addressed through the adoption of innovative technologies such as the use of the roto-aerated dryer, as proposed in this work. • The roto-aerated dryer is an innovative method for coffee drying. • Positive results: reduced residence time, increased drying rate. • Highest drying temperature did not compromise coffee quality. • Quality assessed through markers showed preservation of key components. • Optimal operational conditions identified through desirability analysis, confirmed experimentally. [ABSTRACT FROM AUTHOR]

Coffee is one of the world's most valuable, traded, and widely consumed beverages. As one of the processing steps of coffee, fermentation has gained the attention of researchers as it can be employed to improve coffee quality. The current review presents the latest knowledge regarding the application of fermentation in the coffee industry, including fermenting coffee beans to produce new materials and converting coffee by-products into value-added foods. Fermentation using various microorganisms has been employed to diversify the production of unique food materials from green coffee beans. These products are considered superior to unfermented coffee bean-derrived ones. On the other hand, by-products of coffee processing offer an opportunity to produce microbial metabolites with applications in food. Research indicates that fermentation of coffee by-products shows excellent potential for producing value-added beverages, enzymes, organic acids, and oligosaccharides. As a result, the fermentation process of coffee beans and by-products produces valuable food materials with improved health benefits.Examples of such foods include probiotic coffee, instant coffee with low toxicants, speciality coffee, and coffee wine. Consequently, fermentationhas not only improved the quality of coffee beans but has also offered a viable way to manage waste problems, aiming to create an eco-friendly environment. [Display omitted] • Fermentation improves bioactivity and bioactive compounds of coffee beans. • Probiotic brews, wine, specialty coffee and instant coffee are novel fermented coffee bean products. • Fermentation can bio-transform coffee bean by-products into useful materials. • Enzymes, ethanol, and organic acids are coffee wastes-derived products with industrial applications. • More studies are needed to optimize fermentation conditions for coffee bean. [ABSTRACT FROM AUTHOR]

Coffee is of the most traded commodities in the world and its market has grown regularly over the last 150 years. During production and processing of coffee beans many by-products are generated such as skin, pulp, mucilage, parchment, silverskin, and immature /defective coffee beans. Around 50% of coffee fruit is discard and can contaminate the environment. The purpose of this review is to raise potential applications for coffee by-products in topical formulations. Besides, to present the main bioactive compounds responsible for their biological activity. With population changing habits, use and consumption of natural products has been growing, so there has been greater interest in research in this area. Added to this interest, is the concern caused by the environmental impact caused by tons of industrial waste discarded daily. Coffee by-products have several biological activities, such as antioxidant, anti-inflammatory, antimicrobial, anti-aging, anti-cancer, anti-cellulite and sunscreen. Therefore, they are a good alternative for the composition of topical pharmaceutical and cosmetic formulations, because in addition to their numerous activities, they have low cost, and are sustainable, safe and effective. However, most studies are mainly focused on their antioxidant activity, and studies on the finished product are still lacking. • Coffee by-products can be used in several topical formulations. • The use of coffee by-products in products reduces environmental impact. • More 50% of harvested coffee fruit becomes waste. • Antioxidant potential stands out in the applications of the coffee by-products. • The use of coffee by-products in sunscreen is promising. [ABSTRACT FROM AUTHOR]

• This paper covers the coffee production process, with emphasis on by-products. • The chemical composition of generated by-products was reviewed. • The application of coffee industry by-products in polymer technology was reviewed. • Potential benefits of coffee industry by-products recycling were highlighted. • Coffee industry by-products may act as antioxidants for polymeric materials. Coffee is one of the most popular beverages in the world, and its popularity is continuously growing, which can be expressed by almost doubling production over the last three decades. Cultivation, processing, roasting, and brewing coffee are known for many years. These processes generate significant amounts of by-products since coffee bean stands for around 50% of the coffee cherry. Therefore, considering the current pro-ecological trends, it is essential to develop the utilization methods for the other 50% of the coffee cherry. Among the possibilities, much attention is drawn to polymer chemistry and technology. This industry branch may efficiently consume different types of lignocellulosic materials to use them as fillers for polymer composites or as intermediate sources of particular chemical compounds. Moreover, due to their chemical composition, coffee industry by-products may be used as additives modifying the oxidation resistance, antimicrobial, or antifungal properties of polymeric materials. These issues should be considered especially important in the case of biodegradable polymers, whose popularity is growing over the last years. This paper summarizes the literature reports related to the generation and composition of the coffee industry by-products, as well as the attempts of their incorporation into polymer technology. Moreover, potential directions of research based on the possibilities offered by the coffee industry by-products are presented. [ABSTRACT FROM AUTHOR]

Mechanical dewatering and thermal techniques were evaluated as pre-treatment steps to reduce the water content of spent coffee ground (SCG) powders to thermal conversion. An exploratory evaluation of the fluid dynamic patterns in fluidization of wet SCG powders showed that stable fluidized regimes were achieved with powders of moisture levels under 50 %. Mechanical dewatering was effective to reduce the powder moisture content to 45 %. Adding vibration enhanced the powder feed rate in the drying bed, even for powders with moisture levels that lead to negligible cohesiveness. Using a dimensionless vibration number Γ = 4 with different vibration amplitudes (A = 0.015 and 0.003 m) resulted in different dynamic behaviors and influenced the solids feeding rate but did not affect the mean Sauter diameter of the elutriated powder. Thermal drying at Γ = 4 and A = 0.015 m allowed a steady and continuous operating regime for powder production. Under these vibration parameters, the optimum condition concerning moisture content (22 % w.b.) and mean particle size (0.37 mm) was predicted to occur at 70 °C, and U/U mf = 6. The dry powder was thermally characterized and confirmed the feasibility of using this residue in pyrolysis and combustion processes. The parameters of the reaction kinetic model and the apparent specific heat were obtained. [ABSTRACT FROM AUTHOR]

Fermentation is an important step in coffee processing which promotes the removal of mucilage adhering to the fruits. This process has a direct impact on the coffee quality, and the use of bioreactors and starter cultures has been suggested for process control. In this study, a techno-economic analysis was performed to assess the investment costs and economic performance of the inclusion of a stirred tank bioreactor (STB) model and starter cultures into a coffee processing plant. The total capital investment and production costs for a 45-ton capacity coffee farm operating with 2 STB were US$ 1 million and 0.74 $/kg higher, respectively, than the conventional processing using open tanks. The main factors for rising costs included the implementation of bioreactors (73% of the equipment costs) and starter cultures (88% of the production costs). However, the modern fermentation system (STB with the use of starter cultures) enables the production of specialty coffee beverages with scores among 85.5 and 91.5, which can be sold at 15.50 and 40.92 $/kg, respectively—more than sixteen times the estimated price for commodity coffee. Thus, the techno-economic analysis showed a viable and extremely favorable scenario, providing the economic support for the modernization of coffee fermentation and to value co-creation in the specialty coffee chain. [ABSTRACT FROM AUTHOR]

Research interests in coffee byproducts showed increased attraction. This is partly driven by increasing annual coffee production, which leads to increased generation of solid residues which in turn creates environmental concern. Additionally, compositional profile of coffee byproducts stimulate more investigations into their role of affecting human physiological function. Driven by increased demand of valorizing agro-industrial residues into value added products, many research findings present justifiable importance and possible application of coffee byproducts in food. This extensive review therefore presents up-to-date information with reference to compositional data, potential of incorporating coffee byproducts as ingredients in food formulations and new product development with respect to their biological functionality and technological importance. Reviewed byproducts are coffee husk, pulp, parchment, silverskin and spent coffee ground. Processing steps are elaborated and description of each process with respect to characteristics of starting material and generated main products and resulting residues is made to clearly distinguish the corresponding byproducts. Respective nutritional and phytochemical composition, food formulation and their distinctive characteristics are described. Production of value added products and food product development as well as applications made so far to incorporate the byproducts into food formulation are reviewed. Finally, safety related references and prospective insights of coffee processing byproducts in the current changing economy with possible indication into future trend of the current topic in universal context are presented. • Coffee byproducts contain nutrients and non-nutrients that have both nutritional and functional values. • Composition of coffee byproducts play important role for incorporation of the ingredients into foods. • Biological activities of respective components of the coffee byproducts indicate important health promoting properties. • Physicochemical and techno-functional properties of coffee byproducts are result of chemical characteristics of the materials. [ABSTRACT FROM AUTHOR]

Indonesia is the fourth largest coffee producer in the world, with most of the production managed by smallholders. Analyzing the current environmental impacts of coffee production processes and moving the sector towards lower impact systems, including options for industrial ecology (IE) is critical. The aim of IE for Sustainable Coffee Production (SCP) is primarily toward Zero Waste (ZW), while producing high-quality coffee products that could potentially access new environmentally-oriented markets. Life Cycle Assessment (LCA) was applied in this study to evaluate the environmental impacts of coffee production, from the farm through to various coffee products, focusing on Global Warming Potential (GWP). Data was obtained from a pilot plant operation at Andungsari Coffee Group – Bondowoso, Indonesia, for coffee production using Semi-wash (SW) and Full-wash (FW) processes, from Coffee Cherry Beans (CB) to Green Beans (GB), and Coffee Powder (CP). The novelty of this work was the assessment of the impact of SW and FW, which are not often distinguished by previous studies, and which offer possibilities for improving the grade of coffee products. Observation and experimental data were used to obtain data from production operations to identify the environmental impact and also the potential feedstocks for the production of biogas and other industrial ecology strategies for developing by-products. For both SW and FW the input of 3 tonnes of CB produced 512 kg CP. The LCA indicated that the GWP for 1 kg CP (CB to CP) from SW was 0.765 kg CO 2 - eq , and for FW was 0.741 kg CO 2-eq. In the future, further consideration of alternative by-products will be undertaken in order to produce a more effective IE system towards SCP. [ABSTRACT FROM AUTHOR]

The effects of the microbial community and dynamics on the efficiency of a methanogenic co-digestion system that treats canned coffee processing wastewater and waste activated sludge by means of an anaerobic membrane bioreactor, were investigated and analyzed. The co-digestion system had a chemical oxygen demand (COD) removal efficiency ≥90%, and a COD to methane ratio ≥85%. Phyla Synergistetes , Firmicutes , Proteobacteria and Ca. OP9 were dominant bacteria throughout the investigation, and the main contributors to the hydrolysis and fermentation processes. The degradation paths and functional microbes indicated that genera Caldicoprobacter and Clostridium were the main contributors in the hydrolysis process, while genus Anaerobaculum dominated the acidogenesis and acetogenesis at the most efficient hydraulic retention time (HRT) of 10 d (HRT10). The dominant methanogenesis varied from genus Methanosarcina (71.1%, HRT10) to Methanothermobacter (56.4%, HRT3), indicating a transition from acetic methanogenesis to hydrogen-dependent methanogenesis. Furthermore, a microbial analysis indicated that Acinetobacter was the main contributor to caffeine degradation in this system. This also appears to be the first time that Acinetobacter is reported to be capable of degrading caffeine in the anaerobic condition. Image 1 • Canned coffee wastewater and waste activated sludge were used for co-digestion. • Efficient methanation was sustained at a high OLR of 9.18 g COD/L/d • Functional microbes for specific organics degradation were identified. • Anaerobaculum is the dominant bacteria at the acidogenesis and acetogenesis stages. • Acinetobacter is capable of degrading caffeine in the anaerobic condition. [ABSTRACT FROM AUTHOR]

Highlights • Varying levels of sugars were used to pre-treat Robusta green beans. • Treatment increased the similarity of Robusta to Arabica. • The optimum level of sugar treatment was Robusta soaked in 15F solution. • For coffee aroma the blending ratio can be increased from 20% to 80% Robusta. • The aroma of treated Robusta coffee was more stable than Arabica. Abstract This study attempted to improve Robusta sensory properties by modifying the beans chemical composition. Building on our previous work, which modified bean pH through acid pre-treatment, a model system was developed where, sugar solutions (glucose, fructose, sucrose) were used to pre-treat Robusta coffee beans with the aim to modify the concentration/availability/location of these aroma precursors. Beans were then dried to equal water activity, subjected to equal roast intensity and ground to comparable particle size distributions. The treatment significantly impacted aroma generation during roasting leading to an altered level of pyrazines, furans, ketones, organic acid and heterocyclic nitrogen-containing compounds (p < 0.05). The optimum treatment was 15 g/100 g fructose. 80% treated Robusta could be blended with Arabica in coffee brew without significant aroma differences being perceived when compared to 100% Arabica brew. Furthermore the aroma of the fructose treated Robusta was more stable than Arabica over six weeks accelerated shelflife storage. [ABSTRACT FROM AUTHOR]

This study investigated the transformative effects of incorporating Arabica coffee as a natural additive to improve the overall quality and the sensory properties of date seed coffee. Furthermore, the impact of the freeze-drying process was assessed to provide scientific proof of the marketability of this new product. The enrichment of arabica coffee in the (C + DS) sample led to a higher extractable yield, phenolic content, and consequently a higher antioxidant capacity compared to decaffeinated date seed coffee (DS). (C + DS) coffee showed a volatile profile similar to Arabica coffee (C). It is characterized by an abundance of pyrazines, ketones, and furans and a greater number of potent odorants than (DS) coffee, giving a positive note to the drink. Furthermore, the freeze-dried coffees (C-L) released the highest number of volatile compounds. The perception of coffee was investigated throughout the sensory analysis, which confirmed that evaluators accepted the coffee mixture both before and after freeze drying. [Display omitted] [ABSTRACT FROM AUTHOR]

Instant coffee, like any other food product, is subject to deterioration over time, leading to changes in flavor, aroma, and texture. Additionally, the process of decaffeination can also impact its overall sensory characteristics and shelf-life. In this work, UV–Vis spectroscopy (simulating a homemade coffee cup) and a portable NIR spectrometer (for direct non-destructive analysis) were used to authenticate the shelf-life and decaffeination process of instant coffee samples using Data-Driven Soft Independent Modelling of Class Analogy (DD-SIMCA). For both the authentication approaches, the best results were achieved with sensitivities between 95.0 and 97.1% in the training set, while sensitivities and specificities between 96.2 and 100% were obtained in the test set. Thus, by authenticating the shelf-life and decaffeination process, manufacturers can guarantee that consumers are enjoying a product at its peak freshness and quality, besides providing an additional analytical tool to prevent the ingestion of high levels of caffeine due to its potential health risks in the case of authenticating non-expired decaffeinated instant coffee samples. Therefore, this proposed methodology can contribute to consumer safety, fosters brand reputation, ensures regulatory compliance, and enhances efficiency of production and distribution. Moreover, it can help to plan inventory management, reduce waste, and minimize financial losses, which benefit both the manufacturers and the environment, contributing to sustainability practices. [Display omitted] • Authentication of the shelf-life and decaffeination process of instant coffees. • DD-SIMCA one-class modeling of UV–Vis and NIR spectral fingerprint signatures. • Sensitivities of 97.9 and 100% for authenticating non-expired samples (test set). • Specificities of 100 and 96.2% for authenticating non-expired samples (test set). • Sensitivity and specificity of 100% for authenticating test decaffeinated samples. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a secondary metabolite produced primarily by the genus Aspergillus sp. sections Circumdati and Nigri. It can accumulate in coffee at post-harvest stage. In the present study five different dry processed coffees were sampled from Ivory Coast at harvesting and after drying. The OTA was detected in all the samples, from 3.62 μg/kg of coffee just after harvest to a higher-level of contamination in the dried coffee, between 11.04 and 760.24 μg/kg of coffee. Metabarcoding was used to further study the changes in the mycobiota. The alpha and beta diversity analysis revealed the presence of unique and more diverse fungal communities on the coffee after drying compared to fresh harvested coffee. Specially, coffee dried for a longer period showed a higher diversity. Fungal species such as Hypopichia sp. or Bernettozyma sp., were replaced in the top ten abundant species after drying by species such as Kurtzmaniella sp., Meyerozyma sp. and Fusarium sp. The increasing abundance of the ochratoxigenic fungi, A. carbonarius was correlated to the increased concentration of OTA on coffee. The construction of the negative correlation network shows that some yeasts could be good candidates for the biocontrol of A. carbonarius. The combination of DNA metabarcoding and OTA quantification was effective at deciphering the post-harvest origin of the OTA contamination. Overall, this study highlights the changes in the mycobiota under different drying conditions. Future perspectives include developing actions of prevention and control of the contamination with OTA during the post-harvest stages. • Ochratoxin A (OTA) was detected in fresh cherries and in all treatments. • Extended drying increases OTA contamination. • Ninety-five percent of the OTA is detected in the husk. • Microbial communities' composition of fresh and dried Robusta coffee is different. • A higher A. carbonarius presence after drying was detected through Metabarcoding. • A higher A. carbonarius abundance was concomitant with higher OTA levels. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • AnMBR succeeded co-digestion of coffee wastewater and waste activated sludge. • High TCOD removal efficiencies was achieved as 92 ± 3%. • Optimum methane yield of 0.307 LCH 4 /gCOD occurred at HRT 10 d. • AnMBR has succeeded energy positive at all the operating HRTs. • Maximum net energy potential of 2.82 kJ/gCOD was achieved at HRT 15 d. Abstract A large amount of wastewater is generated in the processing of coffee from fruit to cup. Thermophilic high-solids co-digestion of coffee processing wastewater (CPW) and waste activated sludge (WAS) has been succeeded by anaerobic membrane bioreactor (AnMBR). Chemical oxygen demand (COD) removal efficiencies of 92 ± 3% with an average methane yield of 0.28 LCH 4 /gCOD removed were achieved at a high solids content of 50 g/L in the AnMBR. The optimal digestion performance of 82.4% removal COD conversion to CH 4 was achieved at hydraulic retention time (HRT) 10 d. Energy balance analysis revealed AnMBR has succeeded in energy positive at all the HRTs. The net energy potential (NEP) was determined to average 2.12–2.82 kJ/gCOD, amongst which the maximum NEP was achieved at HRT 15 d. These results indicated the high-solids co-digestion by AnMBR is a promising approach to maximize the bioenergy conversion from the co-substrate of CPW and WAS. [ABSTRACT FROM AUTHOR]

Abstract Post-harvest coffee processing involves a microbial process to remove the mucilage layer adhering to the fruits, prior to storage and transport of the coffee beans. In this study, coffee mucilage removal was done using lactic acid fermentation in a stirred-tank bioreactor (STR). Fermentation assays were done with or without the addition of starter culture (i.e., Lactobacillus plantarum LPBR01), and kinetic parameters, including microbial growth, sugar pulp consumption and metabolite production, were studied. High lactic acid bacteria (reaching 10.7 log CFU/ml at 10 h) were obtained in the STR process with the starter culture, which led to a high lactic acid productivity (0.366 g/l h) and a pH decrease to below 4.0 during the initial 10 h. A temporal analysis using Illumina high-throughput 16S rRNA Gene Sequencing (HTS) showed the Lactobacillus genus's dominance in the inoculation process, as it reached over 88% of read sequences at the end of fermentation, while the Leuconostocaceae family was the dominant bacterial group in the spontaneous treatment. The STR fermentation process led to the production of coffee beans with richer aroma composition and beverages with a notable increase in the sensorial analysis of the coffee beverages compared to those resulting from the conventional process. This new fermentation model can be used to do controlled bean fermentation to supply the coffee industry with homogeneous and high-quality coffee beans. Graphical abstract fx1 Highlights • Coffee beans fermentation was set up in a stirred-tank reactor (STR). • Added L. plantarum starter culture reached over 88% dominance. • Efficient coffee-pulp mucilage removal and metabolite formation were observed. • STR system showed potential reduction of the fermentation time from 24 to 10 h. • Standardized, high-quality coffee beans can be produced using this new system. [ABSTRACT FROM AUTHOR]

Coffee is globally one of the most widely consumed beverages. Due to the high economic importance for the countries that produce, export and import it, its purity and detection of external impurities have been constant concern. In some cases, visual inspection is unreliable in roasted ground coffee because of resemblance in color and the texture of the cheapest fillers. The objective of this work was to evaluate the feasibility of employing Laser Induced Breakdown Spectroscopy (LIBS) for determination of coffee adulteration with chickpea, corn and wheat. For this purpose, LIBS spectra was evaluated with chemometrics methods for classification and quantification of the adulteration ratio. Coefficient of determination and limit of detection values for chickpea, corn and wheat adulteration with Coffee arabica were found as 0.996, 0.995, 0.995 and 0.56%, 0.52% and 0.45%, respectively. With LIBS, prevention of unfair competition, protection of consumers and determination of coffee quality can be achieved. [ABSTRACT FROM AUTHOR]

In this work, an analytical methodology for volatile carbonyl compounds characterization in green and roasted coffee beans was developed. The methodology relied on a recent and simple sample preparation technique, gas diffusion microextraction for extraction of the samples' volatiles, followed HPLC-DAD-MS/MS analysis. The experimental conditions in terms of extraction temperature and extraction time were studied. A profile for carbonyl compounds was obtained for both arabica and robusta coffee species (green and roasted samples). Twenty-seven carbonyl compounds were identified and further discussed, in light of reported literature, with different coffee characteristics: coffee ageing, organoleptic impact, presence of defective beans, authenticity, human's health implication, post-harvest coffee processing and roasting. The applied methodology showed to be a powerful analytical tool to be used for coffee characterization as it measures marker compounds of different coffee characteristics. [ABSTRACT FROM AUTHOR]

The detection of coffee adulteration with soybean and corn by capillary electrophoresis-tandem mass spectrometry was accomplished by evaluating the monosaccharides profile obtained after acid hydrolysis of the samples. The acid hydrolysis, using H 2 SO 4 as a catalyst, increases the ionic strength of the sample impairing the electrophoretic separation. Therefore, Ba(OH) 2 was used to both neutralize the medium and reduce the content of sulfate by precipitation of BaSO 4 . The best separation of nine determined monosaccharides (fucose, galactose, arabinose, glucose, rhamnose, xylose, mannose, fructose and ribose) plus inositol as internal standard was obtained in 500 mmol·L −1 triethylamine, pH 12.3. The monosaccharides are separated as anionic species at this pH. The proposed method is simple, fast (<12.0 min), present linear calibration curves (r 2  = 0.995), and relative standard deviation for replicate injections lower than 5%. The LOQ for all monosaccharides was lower than 0.01 mmol·L −1 , which is in accordance with the tolerable limits for coffee. Principal component analysis (PCA) was used to evaluate interrelationships between the monosaccharide profile and the coffee adulteration with different proportions of soybean and corn. Fucose, galactose, arabinose, glucose, sucrose, rhamnose, xylose, mannose, fructose, and ribose were quantified in packed roast-and-ground commercial coffee samples, and differences between adulterated and unadulterated coffees could be detected. [ABSTRACT FROM AUTHOR]

This work proposes the use of near infrared (NIR) spectroscopy in diffuse reflectance mode and multivariate statistical process control (MSPC) based on principal component analysis (PCA) for real-time monitoring of the coffee roasting process. The main objective was the development of a MSPC methodology able to early detect disturbances to the roasting process resourcing to real-time acquisition of NIR spectra. A total of fifteen roasting batches were defined according to an experimental design to develop the MSPC models. This methodology was tested on a set of five batches where disturbances of different nature were imposed to simulate real faulty situations. Some of these batches were used to optimize the model while the remaining was used to test the methodology. A modelling strategy based on a time sliding window provided the best results in terms of distinguishing batches with and without disturbances, resourcing to typical MSPC charts: Hotelling's T 2 and squared predicted error statistics. A PCA model encompassing a time window of four minutes with three principal components was able to efficiently detect all disturbances assayed. NIR spectroscopy combined with the MSPC approach proved to be an adequate auxiliary tool for coffee roasters to detect faults in a conventional roasting process in real-time. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of organic acid-soaking and sonication on the formation of flavor and α-dicarbonyl compounds in Robusta beans were investigated. • In Robusta coffee processed (3% malic acid-sonicated), furfural and 5-methyl furfural increased by 236.03% and 114.77%, respectively. • α-Dicarbonyls were significantly (p < 0.05) decreased in all Robusta coffees after organic acid pretreatment. • In Robusta coffee processed from coffee beans soaked and sonicated in tartaric acid solution, the α-dicarbonyls decreased by up to 44% and 58%, respectively. In this study, the effects of organic acid-soaking (malic, citric, tartaric, and succinic acid) and sonication on the formation of flavor and α-dicarbonyl compounds in Robusta (C. canephora syn. Coffea robusta) green beans were investigated. A total of 20 volatile compounds were identified in Robusta coffee. Furfural and 5-methyl furfural, two dominant volatile compounds in Arabica coffee, increased after organic acid pretreatment. In Robusta coffee processed from 3% malic acid-soaked coffee beans, furfural and 5-methyl furfural increased by 90.99% and 24.92%, respectively, compared to the control. In Robusta coffee processed from 3% malic acid-sonicated (280 W, 1 h) coffee beans, furfural and 5-methyl furfural increased by 236.03% and 114.77%, respectively. α-Dicarbonyls (glyoxal, methylglyoxal, and diacetyl) were significantly (p < 0.05) decreased in all Robusta coffees after organic acid pretreatment. In Robusta coffee processed from coffee beans soaked and sonicated in tartaric acid solution, the α-dicarbonyls decreased by up to 44% and 58%, respectively, compared to the control. This study suggested the pretreatment methods to enhance the flavor substances and reduce the α-DCs in Robusta coffee. [ABSTRACT FROM AUTHOR]

Due to the extended drying time open-sun and solar drying of coffee procedures undergo, the development of microorganisms, mycotoxins and molds threaten the product. Alternatives such as mechanical dryers are available, nevertheless, their running costs and setups are usually expensive and unaffordable for small-scale coffee growers. Therefore, this research aimed to design, build and evaluate a hybrid solar dryer which mixes solar and mechanical drying principles. It uses a traditional solar tunnel-type dryer as a base featuring a biomass burner which uses coffee trunks left from the yearly crop renovation as biofuel. A heat exchanger heats the drying air, afterwards blown into a plenum chamber that homogenizes the air's static pressure before crossing the coffee bed, ensuring an even moisture removal. Also, the hybrid unit includes a photovoltaic system to obtain a fully self-sufficient drying unit. The newly developed dryer was tested under three different configurations: Solar and mechanical day and night (C1), solar during the day and mechanical during the night (C2) and fully solar with non-mechanical aid (C3). The results displayed a notable drying time reduction in the three evaluated configurations: C1 reduced the drying time by 70.47%, C2 by 45.75% and C3 by 21.5%. Also, the predictive model for different plenum chamber heights was obtained through computational fluid dynamics simulations, where the ideal height was 0.25 m. A biomass consumption of 1.9 kg h−1 was registered. Also improved temperature and relative humidity profiles were achieved. Its design easily adapts to the existing tunnel and parabolic-type solar dryers. [ABSTRACT FROM AUTHOR]

Puffing of coffee beans, which induces heat- and pressure-derived physicochemical changes, was applied as an alternative to roasting. Roasted or puffed coffee beans with equivalent lightness values were compared. The moisture content was higher while the crude fat and protein compositions were lower in puffed beans than in roasted beans. The pH was lower and the acid content was higher in puffed beans than in roasted beans. The roasted beans exhibited greater specific volumes, while the puffed beans displayed greater extraction yields. The trigonelline and total phenolic contents were greater in puffed beans than in roasted beans resulting in an enhanced antioxidant capacity. Sensory evaluation of roasted and puffed coffee bean brews revealed that puffing did not affect the flavor or overall acceptance. The current study provides evidence that puffing is an alternative to roasting coffee beans with various benefits. [ABSTRACT FROM AUTHOR]

On-line analysis of coffee roasting was performed using ion mobility spectrometry–mass spectrometry (IMS–MS) with corona discharge ionization. This is the first time that formation of volatile organic compounds (VOCs) during coffee roasting was monitored not only in positive but also in negative ion mode, and not only with mass spectrometry, but also with ion mobility spectrometry. The temporal evolution of more than 150 VOCs was monitored during the roasting of Brazilian Coffea arabica. Mass-selective ion mobility spectrometry allowed a separation of isobaric and isomeric compounds. In positive ion mode, isomers of alkyl pyrazines were found to exhibit distinct time-intensity profiles during roasting, providing a unique insight into the complex chemistry of this important class of aroma active compounds. Negative ion mode gave access to species poorly detectable by other on-line methods, such as acids. In this study, the release of fatty acids during coffee roasting was investigated in detail. These increase early on in the roasting process followed by a decrease at the same time as other VOCs start to be formed. [ABSTRACT FROM AUTHOR]

This work was performed to evaluate the possible application of PTR-ToF-MS technique in distinguishing between Coffea arabica (Arabica) and Coffea canephora var. robusta (Robusta) commercial stocks in each step of the processing chain (green beans, roasted beans, ground coffee, brews). volatile organic compounds (VOC) spectra from coffee samples of 7 Arabica and 6 Robusta commercial stocks were recorded and submitted to multivariate statistical analysis. Results clearly showed that, in each stage of the coffee processing, the volatile composition of coffee is highly influenced by the species. Actually, with the exception of green beans, PTR-ToF-MS technique was able to correctly recognize Arabica and Robusta samples. Particularly, among 134 tentatively identified VOCs, some masses (16 for roasted coffee, 12 for ground coffee and 12 for brewed coffee) were found to significantly discriminate the two species. Therefore, headspace VOC analyses was showed to represent a valuable tool to distinguish between Arabica and Robusta. [ABSTRACT FROM AUTHOR]

There is a growing demand for use of natural ingredients in food manufacturing. This study utilized a natural emulsifier, quillaja saponin (1%) to fabricate non-dairy model creamer emulsions (containing 10% medium chain triglycerides oil). Varying homogenization conditions, ranging from a high-shear mixer to passing through a microfluidizer at 20,000 psi, were applied to fabricate emulsions. The effect of particle size on the appearance, tristimulus color coordinates, and electrical characteristics of the model creamers and white coffee drinks were investigated. The average droplet size varied from 0.2 to 16 μm. All model creamers had whitish milk-like appearance and the white coffee solutions had light brown color. All systems were physically stable except for the systems with largest oil droplets (1.8 and 16 μm), which had creaming. The lightness, L* (whiteness) of the model creamer and the white coffee increased with decreasing oil droplet size, as smaller droplets scatter more light. Decreasing the oil droplet size led to lower zeta potential (from − 73 to − 54 mV) due to lesser negative charge group accumulated on the interfacial layer of the droplets. The oil droplets were also found to be stable to aggregation in hot acidic coffee solutions prepared using model hard water. Overall, this study found that oil droplets stabilized with natural plant-based surfactant have potential for application in liquid coffee creamers and their stability and whitening power were dependent on the droplet size. [ABSTRACT FROM AUTHOR]

The cost of cellulases is the main bottleneck for bioethanol production at commercial scale. Solid-state fermentation (SSF) is a promising technology that can potentially reduce cellulases cost by using wastes as substrates. In this work, a SSF system of 4.5 L bioreactors was operated continuously by sequential batch operation using the fermented solids from one batch to inoculate the following batch. Coffee husk was used as lignocellulosic substrate. Compost was used as starter in the first batch to provide a rich microbiota. Two strategies were applied: using 10% fermented solids as inoculum in 48 h batches (SB90) and using 50% solids in 24 h batches (SB50). A consistent and robust production process was achieved by sequential batch operation. Similar cellulase activities around 10 Filter Paper Units per gram of dry solids were obtained through both strategies. Microbial diversity in the starting materials and in the final fermented solids was characterized by next generation sequencing. Microbial composition of both fermented solids was similar but the relative abundance of families and species was affected by the operation strategy used. Main bacteria in the final solids came from compost (families Sphingobacteriaceae , Paenibacillaceae and Xanthomonadaceae ), while main fungi families came from coffee husk (families Phaffomycetaceae , Dipodascaceae and two unidentified families of the class of Tramellomycetes ). There was a high presence of non-identified mycobiota in the fermented solids. Main identified species were the bacteria Pseudoxanthonomas taiwanensis (12.3% in SB50 and 6.1% in SB90) and Sphingobacterium composti (6.1% in SB50 and 2.6% in SB90) and the yeasts Cyberlindnera jardinii and Barnettozyma californica (17.8 and 4.1% respectively in SB50 and 34 and 9.1% in SB90), all four previously described as lignocellulose degraders. The development of these operational strategies and further biological characterization of the end product could eventually benefit the process economics by providing a standard and specialized inoculum for a continuous SSF for cellulases production. [ABSTRACT FROM AUTHOR]

The generation of waste is a necessary process related to the production and consumption of coffee. One of the wastes associated with the production of coffee is the husk, which separates from the beans when it is roasted. The waste from the consumption of coffee is spent coffee grounds generated during the coffee brewing process. The study aimed to determine the possibility of coffee production and consumption waste conversion in the anaerobic digestion process. The tested parameters were, among others, biogas efficiency, methane efficiency, and methane content in biogas. The experiment was conducted under anaerobic digestion conditions using DIN 38414/S8 norm. The total solids content of the coffee husk was 93.37%, with the organic matter content at 93.34%. The biogas efficiency in terms of fresh matter was 329.50 m3‧Mg−1. The total solids content of all three analyzed grounds samples ranged from 41.27 to 45.72%. The high volatile solids content, in the 97.91–98.41% range, confirmed the biogas potential. In all three samples of coffee grounds, biogas efficiency was in the range of 225.45–270.97 m3‧Mg−1. The obtained results allow concluding that analyzed coffee production and consumption waste have a high potential for biogas production. [Display omitted] • Biogas efficiency of coffee husk was 329.50 m3‧Mg−1 fresh matter. • Biogas efficiency of spent coffee grounds was in range of 225.45–270.97 m3‧Mg−1 FM. • Both substrates were characterized by similar methane concentrations 52.68–54.50%. • Coffee waste (especially coffee grounds) has short HRT favorable for biogas plants. [ABSTRACT FROM AUTHOR]

• Identified novel compounds that contribute to coffee brew bitterness. • The mixture of compounds enhanced bitterness. • Compounds were reported to function as bitter enhancers with no intrinsic bitter taste. • All compounds were thermal reaction products generated during coffee roasting. The bitterness perception of coffee is a key attribute that impacts consumer acceptance. Nontargeted liquid chromatography/mass spectrometry (LC/MS) flavoromics analysis was applied to identify compounds that enhance the bitter perception of roasted coffee brew. Orthogonal partial least squares (OPLS) analysis was used to model the comprehensive chemical profiles and sensory bitter intensity ratings of fourteen coffee brews with good fit and predictivity. Five compounds that were highly predictive and positively correlated to bitter intensity were selected from the OPLS model, further isolated, and purified using preparative LC fractionation. Sensory recombination testing demonstrated that five compounds significantly enhanced the bitter perception of coffee when presented as a mixture, but not when presented individually. In addition, a set of roasting experiments revealed the five compounds were generated during the coffee roasting process. [ABSTRACT FROM AUTHOR]

Coffee fermentation process to specialty coffee production. [Display omitted] • Coffee fermentation is a multifactorial and rudimentary process. • Fermentation must be considered a separate step in coffee processing. • The fermentation protocols can help variables control and reproducibility of results. • Oxygen availability should be a controlled variable during coffee processing. • Starter cultures can promote changes in epiphytic microbiota during fermentation. In recent years, the importance of controlling coffee fermentation in the final quality of the beverage has been recognized. The literature review was conducted in the Science Direct and Springer databases, considering studies published in the last ten years, 74 references were selected. Several studies have been developed to evaluate and propose fermentation conditions that result in sensory improvements in coffee. So, this review aims to describe detailed the different protocols for conducting the coffee fermentation step and how they could influence the sensory quality of coffee based on the Specialty Coffee Association protocol. We propose a new way to identify coffee post-harvest processing not based on the already known wet, dry and semi-dry processing. The new identification is focused on considering fermentation as a step influenced by the coffee fruit treatment, availability of oxygen, water addition, and starter culture utilization. The findings of this survey showed that each type of coffee fermentation protocol can influence the microbiota development and consequently the coffee beverage. There is a migration from the use of processes in open environments to closed environments with controlled anaerobic conditions. However, it is not possible yet to define a single process capable of increasing coffee quality or developing a specific sensory pattern in any environmental condition. The use of starter cultures plays an important role in the sensory differentiation of coffee and can be influenced by the fermentation protocol applied. The application of fermentation protocols well defined is essential in order to have a good product also in terms of food safety. More research is needed to develop and implement environmental control conditions, such as temperature and aeration, to guarantee the reproducibility of the results. [ABSTRACT FROM AUTHOR]

• Emerging processing methods (EPMs) for coffee bean processing are focused. • Effect of EPMs on properties of coffee beans and regular coffee beans are compared. • EPMs induce formation of flavor precursors in coffee beans. • Strategies to resolve the disadvantages of EPMs are discussed. Emerging processing methods have been applied in coffee bean processing for improved sensory quality. The processes focus on optimizing the fermentation process of the coffee cherries and beans. This involves various pathways, including the formation of volatiles, flavor precursors and organic acids and the reduction in the concentrations of bioactive compounds. Comprehensive information regarding the effect of these emerging processes on the chemical, biological and sensory properties of the coffee beans is summarized. Emerging processes affected the coffee bean to various degrees depending on the raw material and the method used. The emerging methods promoted the reduction of bioactives such as caffeine and phenolics in coffee beans. Substantial improvement of these processes is needed to obtain coffee beans with improved biological activities. Effort to simplify the methods and optimize the post-fermentation process is crucial for the methods to be easily accessible by the producers and to produce defect-free coffee beans. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effect of air flow in coffee roasting for antioxidant activity and phenolic compound content. Roasting was conducted in various combinations of temperature (180–200 °C), time (13–17 min) and volume flow rate (VFR; −0.271–0.271 L/s) using Box-Behnken design. The results of DPPH, ORAC and total polyphenol content (TPC) were fitted to the response surface methodology models (R 2 = 0.9936–0.9869). Increasing temperature and time were negatively influenced for functional properties of roasted coffee with significances ( P < 0.05). The quadratic effect of VFR was observed in DPPH and ORAC assays. Higher DPPH and ORAC values were shown in high or low VFR than the centre point of VFR at the same temperature or time. On the other hand, TPC was decreased from high to low VFR at the same temperature or time. The VFR was a significant parameter for antioxidant activity and TPC in coffee roasting. Manipulation of air flow by increasing or decreasing VFR can deliver higher antioxidants and phenolic compounds from the same amount of coffee beans to consumers. [ABSTRACT FROM AUTHOR]

The effect of roasting conditions on the NIR and HPLC profiles of coffee samples was systematically evaluated by ANOVA-simultaneous component analysis (ASCA), also as a function of the varietal origin (Arabica or Robusta) of the beans. With respect to previously published paper, the use of ASCA allowed not to limit the characterization to individual analytes or specific family of compounds, by extending it to whole instrumental profiles, thus providing a holistic characterization of the roasting process, also in terms of how it changes depending on the species of the raw material. In particular, it was evidenced that both the species and the roasting time have a significant effect on the fingerprints and that, only in the case of NIR spectra, their interaction is significant as well. Moreover, it was possible to highlight what are the main variations in the experimental profiles ascribable to the effects of the controlled factors and in particular, in the case of roasting time, to discover a major longitudinal monotonic trend which is accompanied by a minor one that can be associated to the formation of intermediates. In a successive stage, based on the outcomes of ASCA, partial least squares-discriminant analysis (PLS-DA) and soft independent modeling of class analogies (SIMCA) have been used to build classification models to authenticate the varietal origin of coffee beans by NIR spectroscopy. PLS-DA resulted in about 98% correct classification rate on the test set (100% for Arabica and 95% for Robusta), while sensitivity and specificity values almost always above 90% were achieved with SIMCA (93% and 96%, respectively, for Arabica and 77% and 96% for Robusta). [ABSTRACT FROM AUTHOR]

Two main types of processing are applied to coffee: the dry and wet processes. The aim of this study was to measure the impact of post-harvest processing on coffee microbial ecology and search for microbial markers of process discrimination. Coffee samples were collected in three farms in two locations of West Cameroon (Bafoussam and Dschang). Samples of Coffea arabica were collected along wet and dry methods and Coffea canephora samples were collected only during treatment using the dry method. Bacterial and fungal communities present on coffee beans were determined by using a molecular method PCR-DGGE (Denaturing Gradient Gel Electrophoresis) generating 16S rDNA and 26S rDNA profiles for bacteria and fungi. Results showed that microbial ecology structures were different depending on three main parameters: i) the method applied, ii) the coffee species and iii) their geographical origin. Statistical analysis applied allowed to measure the impact of all parameters and showed that the method was the major parameter influencing microbial communities' structure. Microbial DNA markers that appear specific of coffee origin, species or treatment were identified, such as lactic acid bacteria (LAB) which were detected only during wet process. They are specific of the fermentation step. DNA from Wallemia sp. was only detected in Robusta coffee beans ( Coffea canephora ). The study of microbial communities at the molecular level appears as a promising approach to discriminate between coffee processing types. [ABSTRACT FROM AUTHOR]

This study describes a simple and rapid sampling method employing a polymeric ionic liquid (PIL) sorbent coating in direct immersion solid-phase microextraction (SPME) for the trace-level analysis of acrylamide in brewed coffee and coffee powder. The crosslinked PIL sorbent coating demonstrated superior sensitivity in the extraction of acrylamide compared to all commercially available SPME coatings. A spin coating method was developed to evenly distribute the PIL coating on the SPME support and reproducibly produce fibers with a large film thickness. Ninhydrin was employed as a quenching reagent during extraction to inhibit the production of interfering acrylamide. The PIL fiber produced a limit of quantitation for acrylamide of 10 μg L −1 and achieved comparable results to the ISO method in the analysis of six coffee powder samples. [ABSTRACT FROM AUTHOR]

As coffee is becoming a daily beverage, the coffee processing industry keeps expanding due to the perpetual demands from the global community. Alas, this great demand has also led to large production of wastewater. Coffee processing mill effluent is characterised as acidic wastewater, with high content of organic compounds, pungent odours and colours. It threatens aquatic life, human health and the environment. Thus, there is an urge to seek appropriate methods to treat the effluents so that they comply with regulated environmental limits before dismissal. Realising the importance of green technology and sustainability, the United Nations have initiated a proactive plan known as Sustainable Development Goals to be implemented by nations around the globe to ensure better future for tomorrow. This manuscript outlines a review of coffee processing and its generated wastes, conventional wastewater treatments and current practices. Based on the compiled data, this review aims to highlight the valorisation of coffee processing mill effluent treatment by introducing an environmentally friendly integrated treatment system while adopting the 'zero-waste discharge concept'. This integrated system consists of natural coagulation-flocculation, natural adsorption and phytoremediation to treat specific contaminants in respective effluents. Highlighting the 'zero-waste discharge concept', all by-products from the proposed system can be reclaimed as secondary resources. [ABSTRACT FROM AUTHOR]

• Norharman shows anaerobic fermentation-specific profile. • Effect size of post-harvest processing method was maximal in light roasting. • Characteristic profile of temperature-based brewing method was most preserved in dark roasting. • Light roasted coffee bean was most affected more by pressure-based brewing method. • 9,10 and 12,13-DiHOME, previously unidentified in coffee, was first reported. Our study aims to characterize metabolite profiles, varying by major determinants in brewed coffee as follows: three post-harvest processing, three roasting degrees, and two brewing methods for C. arabica cv. Geisha. The major discriminant factor was the roasting degree, explaining 58.84% of the total variance of metabolite profiles. Despite a lesser degree of influence, specific metabolite profiles were retained in temperature-based brewing (Light, 11.11%; Medium, 12.01%; Dark, 22.15%) and post-harvest processing (Light, 35.29%; Medium, 29.64%; Dark, 22.03%), respectively. The effect of pressure application on the coffee metabolome was significant only for the light roasted beans (9.88%). Of note, the post-harvest processing method was featured by norharman (anaerobic), pimelic acid (natural), and xanthine (washed). In addition, our study proposed novel compounds, DiHOMEs, associated with potential health benefits, which will step-up the coffee values and suggest future direction of the development of coffee processing. [ABSTRACT FROM AUTHOR]

Coffee extract was freeze-concentrated through block and falling-film techniques. Solute retention and concentration efficiency were determined after one stage of these processes. Ice morphology was characterized through image analysis. Preservation of volatile compounds was determined through GC–MS. The effect of coffee extract on flavour was determined after freeze concentration through sensory evaluation. Solute occlusion was higher for falling-film than for block freeze-concentration, with an average distribution coefficient of 0.45 and 0.29, respectively. The ice crystal size was lower for the falling-film technique; this explains the higher solute occlusion. The dewatering capacity was higher for the falling-film technique, as this process is faster than block freeze-concentration. The most abundant volatile compounds of the coffee extracts were preserved after freeze concentration with both techniques. In the same way, no differences were found in most of the sensory attributes of the freeze-concentrated extract obtained using both techniques. Our results confirm the benefits of the block and falling-film freeze concentration techniques in preserving the quality of coffee extracts. [ABSTRACT FROM AUTHOR]

Chitosan beads were prepared, using glutaraldehyde as a crosslinking agent for the immobilization of soybean hull peroxidase (SBP). The activity of free and immobilized SBP was studied. The optimum pH was 6.0 for both the free and immobilized enzyme; however, enzyme activity became more dependent on the temperature after immobilization. This study evaluated the potential use of immobilized and free enzyme in the oxidation of caffeic acid, of synthetic phenolic solution (SPS) and of total phenolic compounds in coffee processing wastewater (CPW). Some factors, such as reaction time, amount of H 2 O 2 and caffeic acid were evaluated, in order to determine the optimum conditions for enzyme performance. Both enzymes showed a potential in the removal of caffeic acid, SPS and CPW, and immobilized SBP had the highest oxidation performance. The immobilized enzyme showed a potential of 50% in the oxidation of caffeic acid after 4 consecutive cycles. [ABSTRACT FROM AUTHOR]

This study was conducted to assess how the Fairtrade label interacts with the perception of intrinsic product characteristics on liking and purchase decisions and to estimate the evolution of this interaction after exposure to coffees and/or exposure to ethical information. In the first session, 119 consumers gave liking scores for 2 regular and 2 Fairtrade coffees under a blind tasting condition. Then, they were asked to indicate the maximum price they would pay for each product in 2 auctions taking place under different information conditions. In the first auction, participants saw the packaging but did not taste the coffee; in the second auction, they could both taste the coffee and see the packaging. After the first session, the consumers were randomly split into 4 groups, and these groups were exposed for one month to different conditions before returning to the lab for exactly the same measurements as in the first session. The first of the 4 groups was not exposed to sensory characteristics or ethical information. Each consumer of the second group was only exposed to sensory characteristics of the coffees (one packet of his/her least liked regular and ethical coffees delivered in blind packaging for home consumption). The third group was exposed to sensory characteristics and ethical information (the same as the second group but using the original coffee packaging showing fair trade information). The final group was only exposed to ethical information. Results showed that the hedonic scores of the least liked ethical and regular products increased from sessions 1 to 2, but not significantly more when consumers were exposed to these products between the sessions. However, while consumers offered lower prices for ethical products at the first session, those who were exposed to ethical information increased their willingness to pay for ethical products. This effect became statistically significant when consumers could taste the products before making their bid. The effect of exposure to ethical information was also transferred to the willingness to pay for the ethical product to which the consumers were not exposed. This study highlights the interest of a design, which makes it possible to assess the impact over time of sensory and external information on the willingness to pay. [ABSTRACT FROM AUTHOR]