Green Coffee Beans Research Articles

Safety evaluation of the food enzyme endo-polygalacturonase from the non-genetically modified Aspergillus tubingensis strain MUCL 55013.

The food enzyme endo-polygalacturonase ((1→4)-α-d-galacturonan glycanohydrolase (endo-cleaving); EC 3.2.1.15)) is produced with the non-genetically modified Aspergillus tubingensis strain MUCL 55013 by Soufflet Biotechnologies. The food enzyme is free from viable cells of the production organism. It is intended to be used in 10 food manufacturing processes: processing of fruits and vegetables for the production of juices, other fruit and vegetable products, wine, distilled spirits from wine, alcoholic beverages other than grape wine; processing of plant-derived products for the production of refined and unrefined sugar, edible oils from plants, green coffee beans by demucilation, coffee extracts and tea and other herbal and fruit infusions. Since residual amounts of total organic solids (TOS) are removed in three processes, dietary exposure was calculated only for the remaining seven food manufacturing processes. Exposure was estimated to be up to 7.834 mg TOS/kg body weight (bw) per day in European populations. Genotoxicity tests did not indicate a safety concern. The systemic toxicity was assessed by a repeated dose 90-day oral toxicity study in rats. The Panel identified a no observed adverse effect level of 2,097 mg TOS/kg bw per day, the highest dose tested, resulting in a margin of exposure of at least 268. A search for the similarity of the amino acid sequence of the food enzyme to known allergens found 14 matches, one of which was to a food allergen. The Panel considered that the risk of allergic reactions upon dietary exposure to this food enzyme cannot be excluded, in particular for individuals sensitised to papaya, but that the risk will not exceed that of consumption of papaya. In addition, oral allergy reactions cannot be excluded in pollen-sensitised individuals. Based on the data provided, the Panel concluded that this food enzyme does not give rise to safety concerns, under the intended conditions of use.

Characterizing the formation of process contaminants during coffee roasting by multivariate statistical analysis.

Coffee is a relevant source of dietary exposure for neoformed furan, alkyl furans and acrylamide. In this study, different statistical methods (hierarchical cluster analysis, correlation analysis, partial least squares regression analysis) were used for characterizing the formation of these process contaminants in green coffee beans roasted under the same standardized conditions. The results displayed a strong correlation between sucrose levels and furans in relation to the other sugars analyzed, while acrylamide formation was strongly related to the free asparagine. The data suggest that a sufficiently large amino acid pool in green coffee favors Maillard-induced acrylamide formation from asparagine, while reactions amongst the carbonyl-containing sugar fragmentation products leading to furan formation are suppressed. If the pool of free amino acids is small, it is depleted faster during roasting, thus favoring the formation of furans by caramelization, basically a sugar degradation process in which reactive carbonyl substances are generated and react together.

Spectrophotometry and chromatography analyses combined with chemometrics tools to differentiate green coffee beans into special or traditional.

Green coffee is the hulled coffee bean, rich in chemical compounds indicative of quality before roasting, making the classification special or traditional. This work aimed to determine compounds in green coffee beans and find the differentiation of green coffee beans into special or traditional ones through chemometrics. For that, the levels of phenolic compounds, reducing, nonreducing, and total sugars were quantified by spectrophotometry: caffeine, trigonelline, 5-hydroxymethylfurfural (5-HMF), 3-hydroxybenzoic, 4-hydroxybenzoic, chlorogenic, caffeic, and nicotinic acids (NAs) by high-performance liquid chromatography-UV-Vis; acetaldehyde, acetone, methanol, ethanol, and isoamyl by HS-GC-FID. Principal component analysis (PCA) was used to differentiate green coffee beans through the levels obtained in spectrophotometric and chromatographic analyses. Statistically, the contents of total phenolic compounds, caffeine, nonreducing sugars, total sugars, NA, 5-HMF, acetaldehyde, ethanol, and ethanol/methanol showed significant differences. The PCA made it possible to classify green coffee beans into special and traditional, in addition to understanding the attributes that influenced the differentiation between coffees. In addition, it was possible to classify green coffee beans into special and traditional, either using all parameters evaluated or only using spectrophotometric analyses. In this way, some advantages allow classification without using a trained and experienced evaluator as their previous experience can influence the results due to their expertise in a certain type of coffee, in addition to being faster and cheaper, especially regarding spectrophotometric analyses.

Identification of potential quality markers in Indonesia’s Arabica specialty coffee using GC/MS-based metabolomics approach

IntroductionThe cupping test is a widely used method for quality assessment of Arabica coffee. However, the cupping test is limited by the low number of certified panelists and the low throughput. Therefore, an analytical-based quality assessment may be a promising tool to complement the cupping test. A present, there is no report investigating quality marker candidates, focusing only on “specialty” grade Arabica coffee from Indonesia.ObjectiveThis study identified the potential quality marker(s) in Arabica Specialty coffee at different stages (green beans, roasted beans, and brewed coffee.MethodsThe metabolite profiles of ten different Arabica specialty-grade coffees were analyzed with different cup scores using gas chromatography–mass spectrometry (GC/MS). From the ten samples, green coffee beans, roasted coffee beans, and brewed coffee were selected. In addition, an orthogonal projection to latent structure (OPLS) regression analysis was conducted to obtain a potential quality marker based on the variable importance in projection (VIP). The potential quality marker(s) were validated by GC/MS metabolome profiling and OPLS analysis of different sets of samples consisting of 35 Arabica specialty-grade coffee samples.ResultsIn Arabica coffee samples, the OPLS model of the three stages showed galactinol to have a high VIP score. Galactinol showed a consistent positive correlation with cup scores at all stages of coffee production (green beans, roasted beans, and brewed coffee). The correlation suggests galactinol is a potential quality marker after further validation using different samples.ConclusionGC/MS combined with OPLS regression analysis suggested galactinol as a quality marker and provide an early screening method for Arabica coffee quality that complements the cupping test performed by certified panelists.

Natural fermentation with delayed inoculation of the yeast Torulaspora delbrueckii: Impact on the chemical composition and sensory profile of natural coffee

All coffee production stages occur in a microbiome, which is generally composed of bacteria, yeasts, and filamentous fungi. The use of starter cultures in post-harvest processing stages is an interesting alternative, since they promote faster removal of mucilage and incorporation of compounds that improve sensory quality, which can result in diverse sensory attributes for the beverage. This study was therefore developed with the objective of evaluating the effect of the following processing procedures on the chemical and sensory characteristics of the coffee beverage: first, fermentation of coffee fruit of the yellow Catucaí variety of Coffea arabica with indigenous microorganisms, followed by inoculation of the starter culture Torulaspora delbrueckii CCMA 0684 during the drying stage. The fruit was divided into two lots, which were differentiated by a natural fermentation process before drying began. The starter culture was inoculated on the coffee at different times during the drying process: at 0 h, 24 h, 48 h, or 72 h after drying began. The sensory attributes, the volatile compound composition of the roasted beans, the organic acid profile, the bioactive compounds, and the fatty acid profile of the green coffee beans were analyzed. The fatty acid and bioactive compound content showed little variation among treatments. Analysis of volatile compounds and organic acids and evaluation of sensory attributes made it possible to distinguish the two treatments. We conclude that natural fermentation of coffee fruit improve the chemical and sensory quality of the coffee beverage. The effect of natural fermentation may be before inoculation of the starter cultures or even during drying.

Enhancing Bioactivity and Conjugation in Green Coffee Bean (Coffea arabica) Extract through Cold Plasma Treatment: Insights into Antioxidant Activity and Phenolic-Protein Conjugates.

Cold plasma technology is gaining attention as a promising approach to enhancing the bioactivity of plant extracts. However, its impact on green coffee bean extracts (GCBEs) still needs to be explored. In this study, an innovative underwater plasma jet system was employed to investigate the effects of cold plasma on Coffea arabica GCBEs, focusing on the conjugation reflected by the change in composition and bioactivity. The DPPH radical scavenging antioxidant activity exhibited a gradual increase with plasma treatment up to 35 min, followed by a decline. Remarkably, at 35 min, the plasma treatment resulted in a significant 66% increase in the DPPH radical scavenging activity of the GCBE. The total phenolic compound content also displayed a similar increasing trend to the DPPH radical scavenging activity. However, the phenolic profile analysis indicated a significant decrease in chlorogenic acids and caffeine. Furthermore, the chemical composition analysis revealed a decrease in free amino acids, while sucrose remained unchanged. Additionally, the SDS-PAGE results suggested a slight increase in protein size. The observed enhancement in antioxidant activity, despite the reduction in the two major antioxidants in the GCBE, along with the increase in protein size, might suggest the occurrence of conjugation processes induced by plasma, particularly involving proteins and phenolic compounds. Notably, the plasma treatment exhibited no adverse effects on the extract's safety, as confirmed by the MTT assay. These findings indicate that cold plasma treatment holds significant promise in improving the functional properties of GCBE while ensuring its safety. Incorporating cold plasma technology into the processing of natural extracts may offer exciting opportunities for developing novel and potent antioxidant-rich products.

Monitoring of Chemical Changes in Coffee Beans during the Roasting Process Using Different Roasting Technologies with Nuclear Magnetic Resonance Spectroscopy

The roasting process is an important step in coffee production, leading to important physical and chemical changes that are responsible for the sensory quality of a coffee beverage. Besides the commonly used drum roasters, a newly developed infrared roaster can be used to roast green coffee beans. In this study, 1H nuclear magnetic resonance (NMR) spectroscopy was used to analyze the fat and aqueous extracts of coffee beans roasted to different degrees of roasting using a professional drum roaster, a hot air fluidized bed sample roaster and an infrared roaster. Caffeine-containing and decaffeinated Coffea arabica coffee samples were used to monitor the roasting process in the different roasters. Compared with the drum-roasted coffee sample, the formation and degradation of NMR-detectable components in the coffee sample roasted with the infrared roaster and the hot air roaster were time-dependent. In the decaffeinated coffee sample, compounds such as kahweol, caffeoylquinic acid and trigonelline were found to occur at lower levels. The formation and degradation of the NMR-detectable compounds in the decaffeinated coffee sample also occurred with a time lag or to a lesser extent than in the caffeine-containing coffee sample.

Perbandingan Asam Fenolat dan Total Fenolik Kopi Arabika Bogor dari Pengolahan Pascapanen dan Tingkat Sangrai Berbeda

Coffee is rich in phenolic compounds, which can be evaluated by the total phenolic or specific individual phenolics. The composition and concentration of phenolics in coffee are affected by various factors, including postharvest and roasting. This study aimed to compare the ratio of phenolic acid (measured as chlorogenic acid) to total phenolic in Bogor arabica coffee, considering different postharvest treatments and roasting levels. The coffee samples were treated with different postharvest (dry, wet, and honey) and roasting processes (light and dark). Green coffee bean was used as a control. The roasting process involved heating the coffee at temperatures ranging from 147.9 to 178.8°C for light roasting, and 190.2 to 200°C for dark roasting (10 minutes each). The color of the coffee beans, concentration of phenolic acid in the coffee extract, and total phenolic in the coffee extract were analyzed using a colorimeter, HPLC, and spectro-photometer respectively. The results showed that roasting significantly intensified the dark color of Bogor arabica coffee. Among the phenolic acids, the 5-CQA isomer emerged as the most dominant and was also the most susceptible to degradation during roasting. As the roasting level increased, the concentration of phenolic acid consistently decreased. Interestingly, the total phenolic initially increased in light roasted coffee but decreased in dark roasted coffee. Green coffee beans exhibited the highest proportion of phenolic acid (83%), whereas dark roasted coffee had the lowest proportion (19%). Although light roasted coffee had the highest total phenolic, its phenolic acid concentration decreased significantly compared to green coffee beans.

Determination of Lipids and Fatty Acids in Green Coffee Beans (Coffea arabica L.) Harvested in Different Agroclimatic Zones of the Department of Quindío, Colombia

The objective of this work was to quantify and characterize the lipid fraction of coffee beans grown in different agroclimatic zones of the department of Quindío, seeking to provide coffee growers with useful information about the coffee produced on their farms and the ability to determine coffee quality and sensory attributes. The lipid extraction process was carried out using two different methods: Soxhlet and Soxtec. The bias was established through concordance analysis using the Bland–Altman test to determine the correlation between the two extraction methods. The final results were compared for each agroclimatic zone, and no significant differences were found between the values for average lipid content of the coffee, which varied between 12.01% and 12.90%. When characterizing the profile of fatty acids present in the lipid fraction of coffee using the technique of gas chromatography coupled to mass spectrometry, it was evidenced that the major acids present in the green coffee bean were linoleic acid and palmitic acid, with an average content between 39.83–40.83% and 36.92–37.90%, respectively, and that these fatty acid contents presented statistically significant differences in areas with higher elevations, higher relative humidity and less sunlight (zones 3 and 4). Stearic acid presented differences in all of the agroclimatic zones.

Analysis on the Added Value of Excelsa Coffee (Coffea liberica var. dewevrei) in Wonosalam, Jombang

The district of Wonosalam in Jombang, Indonesia, harbors significant potential in the agribusiness sector, with a particular focus on Excelsa coffee. Excelsa coffee is currently being cultivated with the vision of establishing it as a signature commodity of Wonosalam. This study is dedicated to analyzing the value transformation that occurs during the conversion of coffee cherries into green beans, further processing of green beans into roasted beans, and providing recommendations for enhancing added value. The study employed a purposive sampling technique, with data analysis conducted using the Hayami method. Nineteen respondents engaged in Excelsa coffee processing participated in the study. The findings of this study demonstrate that the conversion of cherries into Excelsa coffee green beans and the subsequent transformation of green beans into roasted beans indeed contribute to increased value. Specifically, the added value of green beans for Excelsa coffee amounts to IDR 1,153 per kilogram, while the added value for red-picked Excelsa coffee reaches IDR 4,458 per kilogram. Furthermore, the added value of Random Excelsa coffee roast beans is calculated at IDR 12,525 per kilogram, with red-picked Excelsa coffee roast beans achieving an added value of IDR 35,525 per kilogram. To further enhance the added value of Excelsa coffee, improvements can be made in post-harvest quality and downstream processing of coffee.

PENGARUH JENIS KEMASAN TERHADAP KARAKTERISTIK FISIKOKIMIA DAN SENSORI KOPI ARABIKA GAYO DENGAN METODE PENGOLAHAN SEMI BASAH

<p class="10Judulbab">Indonesia is the 4th largest coffee producer after Brazil, Vietnam and Colombia. The largest Arabica coffee production center in Indonesia is in Central Aceh District. Biophysical factors, such as soil conditions, climate and altitude, which are planted at an altitude of 1,000-1,400 meters above sea level are the factors that make Gayo Arabica coffee green bean known as a special coffee that has a strong coffee taste and characteristics. Coffee has a lot of chemical content in it, for example the content of chlorogenic acid and caffeine. Physicochemical analysis of the samples included moisture content, ash content, fat content, protein content, caffeine content, phenol content, acidity level (pH), and specific volume. This data analysis used a completely randomized design with 3 replications comparing coffee from each coffee processing using five types of storage packaging for 4 months. Semi-wet processed coffee has the characteristics of moderate acidity, sweet taste, medium to low.</p><p class="10Judulbab"> </p><p class="10Judulbab">Keywords:<em> Gayo Arabica, semi washed, green bean, storage, Packaging</em></p>

Pengaruh Metode Pengolahan Kopi Robusta Gumitir Di Kabupaten Jember Terhadap Karakteristik Green Coffee Powder (GCP)

Coffee is a plantation crop commodity that is widely consumed in Indonesia as a refreshing drink. Broadly speaking, coffee processing methods include natural processing, honey processing, semi-wet processing, and wet methods. Green coffee powder (GCP) is unroasted coffee that is ground to a certain particle size. Green coffee powder as a new product processed from green coffee without roasting, so in the processing process it is necessary to analyze the profile of green coffee beans. The differences in the processing methods of natural process coffee, honey process, semi wet process, and wet process are related to the physical and chemical characteristics of green coffee powder. GCP began to be recognized by the public because of its benefits as a functional food product that can increase body metabolism and lose weight. The research method used is Non Factorial Complete Randomized Design (RAL Non Factorial) and descriptive method. The treatment consisted of 4 processing methods, namely natural process, honey process, semi wet process, and wet process, so that 4 treatments were obtained with 5 replicates and 20 experimental units were obtained. The data were analyzed using the ANOVA analysis of variance method and continued with the BNT further test with a confidence level of 95%. The results showed a very significant difference from the effect of processing methods on the parameters of camba density and moisture content. While the effect of processing method did not give a significant difference to the parameters of yield and pH produced. In addition, from the results of chemical characteristics research, there are differences in the amount of caffeine content and volatile compounds from each processing method. Of these compounds that give the strongest aroma to green coffee powder is the compound Pyrazine, methyl- (CAS) Methylpyrazine.

Production of functional Arabica and Robusta green coffee beans: Optimization of fermentation with microbial cocktails to improve antioxidant activity and metabolomic profiles

Currently, growing recognition of the health benefits associated with functional foods and beverages has increased the demand for products that offer more than just basic nutrition. Coffee is a widely consumed beverage, in which fermentation of green coffee beans contributes to the development of a special aroma and higher levels of antioxidants. The objectives of this study were to optimize the fermentation conditions and simultaneously improve antioxidant activity and metabolites. The conditions optimized by Box–Behnken design (BBD) suggested that the highest total esters, total phenolic content (TPC), and antioxidant activity (ABTS, DPPH, FRAP) could be reached by fermentation at 30 °C for 2 days with 13.25% sucrose (w/w) using a microbial cocktail. Two sets of selective microbial starters, Lactiplantibacillus plantarum TISTR 2265 (LP) and a cocktail of TISTR yeasts with LP (YC-LP), were further considered as powerful starters for solid-state fermentation (SSF) of Arabica and Robusta beans, enhancing antioxidant activity within the first 3 days of fermentation. Arabica beans fermented by LP reached 198.03% TPC, 44.21% ABTS, 90.35% DPPH, and 97.13% FRAP, while Robusta beans fermented by YC-LP showed 108.24% TPC, 204.19% ABTS, 170.71% DPPH, and 59.60% FRAP, higher than an uninoculated starter. The analysis of 41 fermented metabolites revealed the different metabolomic profiles for both coffee beans, offering valuable insight into the correlation between chemical constituents and functional characteristics. This study represents the first comprehensive comparison of the metabolomic profiles of fermented Arabica and Robusta green coffee beans.

Support vector regression for prediction of stable isotopes and trace elements using hyperspectral imaging on coffee for origin verification

The potential of using rapid and non-destructive near-infrared – hyperspectral imaging (HSI-NIR) for the prediction of an integrated stable isotope and multi-element dataset was explored for the first time with the help of support vector regression. Speciality green coffee beans sourced from three continents, eight countries, and 22 regions were analysed using a push-broom HSI-NIR (700–1700 nm), together with five isotope ratios (δ13C, δ15N, δ18O, δ2H, and δ34S) and 41 trace elements. Support vector regression with the radial basis function kernel was conducted using X as the HSI-NIR data and Y as the geochemistry markers. Model performance was evaluated using root mean squared error, coefficient of determination, and mean absolute error. Three isotope ratios (δ18O, δ2H, and δ34S) and eight elements (Zn, Mn, Ni, Mo, Cs, Co, Cd, and La) had an R2predicted 0.70 – 0.99 across all origin scales (continent, country, region). All five isotope ratios were well predicted at the country and regional levels. The wavelength regions contributing the most towards each prediction model were highlighted, including a discussion of the correlations across all geochemical parameters. This study demonstrates the feasibility of using HSI-NIR as a rapid and non-destructive method to estimate traditional geochemistry parameters, some of which are origin-discriminating variables related to altitude, temperature, and rainfall differences across origins.

Financial Feasibility Analysis of Arabica Powder Coffee in Drip Bag Packaging (Case Study of Berdikari Farmer Group, Sumedang District)

Arabica coffee powder in drip bag packaging is a new product innovation created to fulfill consumer desires and increase product sales. This study aims to analyze the financial feasibility of arabica coffee powder in drip bag packaging. Primary data was collected through direct observation and interviews while secondary data was collected from published scientific references. Financial analysis is carried out to obtain information on Production Costs (BP), Cost of Production (HPP), Net Present Value (NPV), Benefit Cost Ratio (BCR), Internal Rate of Return (IRR) and Payback Period (PBP). The results showed that natural processing of coffee beans with a production capacity of 84,143 drip bag packages per month and raw materials for green coffee beans with a moisture content of 30% - 40% resulted in a production cost of IDR 143,603,885.74 per month and HPP of IDR 1 .706.67 per drip bag. At a product selling price of IDR 2,500.00 per drip bag packaging, an NPV value of IDR 4,118,480,686 was obtained, a BCR of 1.44, an IRR of 36.00% and PBP occurred in the 3rd month.

A Consumer Assessment of Fermented Green Coffee Beans with Common Beer/Wine Yeast Strains for Novel Flavor Properties

Fermentation is a critical step in the production of coffee when following standard wet processing, one of the most common methods used to remove the mucilage layer from coffee cherries. During this step, the de-pulped coffee cherries undergo fermentation with native yeast that modifies the flavor profile of the resultant coffee. This study aimed to ferment green coffee beans using commercial yeast strains from beer and wine prized for their ability to produce specific flavors, and subsequently evaluate the aroma and flavor of the coffee using coffee consumers. Four Saccharomyces cerevisiae strains were used: Belgian Ale, Sourvisiae, 71 B, and Tropical IPA, along with one non-Saccharomyces, Toluraspora delbrueckii (Biodiva), and a non-inoculated control sample. The green coffee beans underwent a controlled wet fermentation for 72 h, followed by roasting, grinding, and brewing. Results showed that flavor profiles varied broadly by yeast strain, suggesting that producing novel flavors in coffee through fermentation is feasible and that these flavors survive the roasting process; however, higher liking scores were still reported for the control sample compared to the fermented samples. Biodiva, a strain used in wine to produce esters and fruity flavors, resulted in coffee with highly fruity notes, and all strains were rated more floral than the control, while the sample fermented with Sourvisiae yeast used in the brewing of sour ales resulted in coffee that was both perceived as more sour and had the lowest pH, likely due to the degree of lactic acid this strain is engineered to produce. Further, there were significant color differences between the samples. In conclusion, fermenting green coffee beans with brewing and winemaking yeast strains strongly impacted the flavor and aroma of the resultant coffee; however, evaluating larger panels of strains or optimizing strain performance may yield flavor profiles more suitable for coffee.

Effect of storage conditions on the chemical and sensory quality of pulped natural coffee

Due to the social and economic importance of specialty coffees, there is a constant effort to develop storage techniques for green coffee beans that effectively preserve the chemical and sensory quality of the product. The objective of this study was to evaluate how the application of cooling along with the use of high-barrier packaging affects the quality of pulped natural coffee over nine months of storage. Commercial pulped coffee beans (Coffea arabica L.) classified as specialty coffee (82 points on the SCA scale) were purchased. They were stored under two environment conditions (controlled cool temperature, and un-controlled ambient conditions) in two packages (one permeable – jute; and the other impermeable – high barrier to gases, light, and water vapor). The sensory and chemical quality of the stored beans was evaluated at the beginning and at six and nine months during storage. The results of sensory analysis indicate that the quality of the samples stored in a refrigerated environment in high-barrier packaging was preserved, and the beans did not exhibit defects after 9 months of storage. Regarding chemical quality of the beans, the high-barrier packaging was able to preserve the fatty acid composition of the green coffee beans, regardless of the storage environment. However, only the refrigerated environment along with this packaging preserved the bioactive compounds of the green coffee beans. The results are promising for creating better storage conditions of the beans, provided by the packaging and/or temperature conditions over time.

Analysis of volatile and nonvolatile compounds in decaffeinated and regular coffee prepared under various roasting conditions

This study investigated the effect of various roasting conditions on regular and decaffeinated green beans. Regular and decaffeinated green beans from Guatemala, Brazil, Ethiopia, and Colombia were prepared under light, medium, and dark roasting conditions. Analysis of the decaffeination-induced changes in nonvolatile compounds revealed that decaffeinated green coffee beans had significantly lower concentrations of trigonelline (25%) and total carbohydrates (16%) but a higher chlorogenic acid content (10–14%) than regular green coffee beans (bothp < 0.05). Flavor differences between regular and decaffeinated coffee were investigated by analysis of the volatile and nonvolatile compounds in roasted coffee beans. From the odor impact ratio values, 3-ethyl-2,5-dimethyl pyrazine, 5-methyl furfural, and guaiacol were primarily responsible for coffee flavor. 3-Ethyl-2,5-dimethyl pyrazine had 58% lower concentration in decaffeinated coffee than in regular coffee. This study is valuable in providing the chemical composition of decaffeinated coffee and way to improve the quality of decaffeinated coffee.

Discovery of ACE Inhibitory Peptides Derived from Green Coffee Using In Silico and In Vitro Methods.

Inhibition of angiotensin-I converting enzyme (ACE) is an important means of treating hypertension since it plays an important regulatory function in the renin-angiotensin system. The aim of this study was to investigate the ACE inhibitory effect of bioactive peptides from green coffee beans using in silico and in vitro methods. Alcalase and thermolysin were employed to hydrolyze protein extract from coffee beans. Bioactive peptides were identified by LC-MS/MS analysis coupled with database searching. The potential bioactivities of peptides were predicted by in silico screening, among which five novel peptides may have ACE inhibitory activity. In vitro assay was carried out to determine the ACE inhibitory degree. Two peptides (IIPNEVY, ITPPVMLPP) were obtained with IC50 values of 57.54 and 40.37 μM, respectively. Furthermore, it was found that two inhibitors bound to the receptor protein on similar sites near the S1 active pocket of ACE to form stable enzyme-peptide complexes through molecular docking, and the Lineweaver-Burk plot showed that IIPNEVY was a noncompetitive inhibitor, and ITPPVMLPP was suggested to be a mixed-type inhibitor. Our study demonstrated that two peptides isolated from coffee have potential applications as antihypertensive agents.

Chlorogenic acid in green bean coffee on body weight: a systematic review and meta-analysis of randomized controlled trials

BackgroundSupplemental green bean coffee extract (GBCE) with caffeine has been shown to prevent weight gain. There are different dosages of GBCE that contain chlorogenic acid (CGA), and the data for their effectiveness in preventing weight gain (500 mg/day) is currently out of date. To better understand the effects of GBCE containing CGA on body weight, the present study sets out to perform a systematic review and meta-analysis of these studies.MethodsUsing electronic databases, including Scopus, Embase, PubMed, and Cochrane Library databases, literature was searched up to October 13, 2022. For the meta-analysis examining the impact of GBCE containing CGA (500 mg/day) on body weight with a random-effects model, the randomized controlled trials (RCTs) were considered. We calculated weighted mean differences and 95% confidence intervals (CIs). To gauge study heterogeneity, the Cochran Q statistic and I-squared tests (I2) were employed.ResultsThe meta-analysis includes three RCTs with 103 individuals (case = 51, control = 52). The combined findings of GBCE with CGA at least 500 mg/day result in body weight reduction (WMD: − 1.30 and 95% CI: − 2.07 to − 0.52, p = 0.001) without study heterogeneity (I2 = 0%, p = 0.904) and without publication bias estimated using Egger’s and Begger’s test (p = 0.752 and p = 0.602, respectively).ConclusionsAccording to the meta-analysis, GBCE with CGA 500 mg/day lowers body weight. Nevertheless, despite its limited sample size and short-term study, this study was successful. Long-term research on the effectiveness and safety of GBCE and CGA on body weight require more clinical trials.Systematic review registrationPROSPERO CRD42021254916.