Roasted Coffee Beans Research Articles

Extraction of Diterpene-Phytochemicals in Raw and Roasted Coffee Beans and Beverage Preparations and Their Relationship.

Cafestol and kahweol are expressive furane-diterpenoids from the lipid fraction of coffee beans with relevant pharmacological properties for human health. Due to their thermolability, they suffer degradation during roasting, whose products are poorly studied regarding their identity and content in the roasted coffee beans and beverages. This article describes the extraction of these diterpenes, from the raw bean to coffee beverages, identifying them and understanding the kinetics of formation and degradation in roasting (light, medium and dark roasts) as the extraction rate for different beverages of coffee (filtered, Moka, French press, Turkish and boiled). Sixteen compounds were identified as degradation products, ten derived from kahweol and six from cafestol, produced by oxidation and inter and intramolecular elimination reactions, with the roasting degree (relationship between time and temperature) being the main factor for thermodegradation and the way of preparing the beverage responsible for the content of these substances in them.

Properties and Anti-Inflammatory Effects of Fermented Product Using Yeast on Roasted Coffee Beans Extracts

Properties and Anti-Inflammatory Effects of Fermented Product Using Yeast on Roasted Coffee Beans Extracts

Exploring correlations between green coffee bean components and thermal contaminants in roasted coffee beans

This study evaluated chemical compositions of green coffee beans from multi-production regions and correlated this information with thermal contaminants in roasted coffee. Using multivariate statistical techniques, formation of 5-hydroxymethylfurfural (5-HMF), furan, 2- and 3-methylfuran were positively correlated with lipid, sucrose, glutamic acid, phenylalanine, margaric acid, linolenic acid and trigonelline in green coffee beans. Moreover, significant positive correlations between acrylamide (AA) levels with aspartic acid, serine, alanine, histidine, asparagine, protein, and caffeine was found in green beans. Despite this, 5-HMF, furan, 2- and 3-methylfuran showed negative correlations with active constitutes (neochlorogenic acid, cryptochlorogenic acid, caffeine, total phenolics (TPC) and total flavonoids contents (TFC)), and several amino acids, and there were slight negative relationships between AA and myristic acid, palmitic acid, chlorogenic acid, sucrose, lipid, TPC and TFC. This study provides valuable enlightenment for the selection of proper coffee beans for production of coffee with high nutrition and low chemical hazardous risks.

Effect of different drying airflows and harvest periods on the quality of specialty coffee (Coffea arabica L.)

Coffee is one of the most consumed commercial beverages worldwide, and coffee growers are constantly seeking innovative processing techniques to improve the quality of the final product. This study evaluated the influence of four drying airflows and three harvest periods on the chemical composition of green and roasted specialty coffee beans. The samples were obtained from the Hacienda La Papaya in Loja, Ecuador. Liquid and gas chromatographic techniques characterized the chemical profile of coffee beans, and sensory analysis was performed using the Specialty Coffee Association of America methodology. In total, 49 compounds were described, 29 in green beans and 20 in roasted beans. A significant (p<0.05) effect of the harvest period was observed in all phenolic compounds except for chlorogenic acid. The drying type significantly affected the levels of rutin and trigonelline. In addition, samples from different harvest periods observed significant differences in the levels of the amino acids serine, arginine, phenylalanine and leucine. Similarly, the drying type significantly influenced glycine, alanine, valine and isoleucine levels. For all drying-harvest combinations, the final cupping score was higher than 85/100, as the different drying processes slightly influenced the cupping attributes. Drying with minimal airflow was characterized by a low balance and intense flavor while drying with medium airflow presented a high ratio and soft body. The harvest period and drying type cannot be used as cupping predictors since no clear trends were observed to classify specialty coffee organoleptic attributes. Therefore, other variables involved in specialty coffee processing should be explored to evaluate higher sensitivity toward flavor prediction and innovation. Keywords: chromatographic analysis, Coffea arabica L., sensory analysis, specialty coffee.

Variation of bioactive compounds and 5-hydroxymethyl furfural in coffee beans during the roasting process using kinetics approach

This study investigated the changes in major bioactive compounds and 5-hydroxymethyl furfural (5-HMF) in coffee beans during the roasting process. A Kinetics model was employed to simulate these changes and investigated the thermostability, and the Pearson correlation analysis was applied to indicate the relationship between bioactive compounds and 5-HMF. The research found that three Caffeoylquinic acids (3-CQA, 5-CQA, 4-CQA), and 5-HMF followed a dynamic pattern of increase in the early stage of the roasting process and decrease afterward, which was described by the combination of zero-order and first-order kinetics model. All fitting models fit well and the rate constant (k) of all models follows the Arrhenius law. Therefore, to obtain a higher concentration of bioactive compounds and lower levels of 5-HMF, light or medium roasted coffee beans are recommended. The Pearson correlation analysis indicated that the high levels of 3-CQA, 4-CQA, and caffeine may correspond to higher levels of 5-HMF after roasting.

Physical and Oxidative Stabilization of Oil-In-Water Emulsions by Roasted Coffee Fractions: Interface- and Continuous Phase-Related Effects.

Emulsions fortified with polyunsaturated fatty acids are highly relevant from a nutritional perspective; however, such products are prone to lipid oxidation. In the current work, this is mitigated by the use of natural antioxidants occurring in coffee. Coffee fractions with different molecular weights were extracted from roasted coffee beans. These components were positioned either at the interface or in the continuous phase of emulsions where they contributed to emulsion stability via different pathways. Coffee brew as a whole, and its high-molecular-weight fraction (HMWF), was able to form emulsions with good physical stability and excellent oxidative stability. When added post-homogenization to the continuous phase of dairy protein-stabilized emulsions, all coffee fractions were able to slow down lipid oxidation considerably without altering the physical stability of emulsions, though HMWF was more effective in retarding lipid oxidation than whole coffee brew or low-molecular-weight fraction. This is caused by various effects, such as the antioxidant properties of coffee extracts, the partitioning of components in the emulsions, and the nature of the phenolic compounds. Our research shows that coffee extracts can be used effectively as multifunctional stabilizers in dispersed systems leading to emulsion products with high chemical and physical stability.

On the radiotoxic 210Po in coffee beans worldwide and the impact of roasting and brewing on its extraction into beverages: from the experiments to 210Po content prediction

We determined radiotoxic 210Po in roasted coffee beans from different regions worldwide, the beverages, and tried to create the prediction model of 210Po content based on its growth location. Additionally, the experiments on 210Po losses and extraction were performed to describe the actual exposure to 210Po. 210Po concentrations in coffee beans and brews tuned out low (maximally of 0.20 Bq∙kg−1 and 2.31 Bq∙L−1, respectively). We assessed the impact of the roasting process on 210Po content and its losses at a maximum of 56.7%. During infusion experiments, we estimated the extraction of 210Po to the coffee brew at a maximum of 40.6%. The amount of 210Po in the coffee brew depended on the infusion style and water type. We calculated the effective radiation doses from the coffee drink ingestion. Coffee drinking does not contribute significantly to the annual effective radiation dose worldwide.Graphical

Comparison of Antibacterial Effectiveness of Arabica Coffee Bean Extract (Coffea arabica L.) Roasted and Non-Roasted Against Bacteria Enterococcus faecalis

Background: Dental caries that are not handled properly cause cavities and open the dental pulp so that it becomes a pathway for microorganisms to enter the root canals. The most common microorganisms found in root canal infections are Enterococcus faecalis. Arabica coffee beans have bioactive compounds such as alkaloids, saponins, and tannins, which inhibit the growth of bacteria. This study aimed to compare the antibacterial effectiveness of roasted and non-roasted Arabica coffee bean extracts against bacteria Enterococcus faecalis.
 Methods: This study was an in vitro experimental study. This research uses culture Enterococcus faecalis, which were divided into 10 groups (2 control groups, 4 treatment groups of roasted coffee beans, and 4 groups of non-roasted coffee beans). Inhibition zone diameter analysis was carried out with the help of SPSS using univariate and bivariate.
 Results: Non-roasted Arabica coffee bean extract showed better effectiveness in inhibiting bacterial growth Enterococcus faecalis, along with increasing the concentration of the extract.
 Conclusion: Non-roasted Arabica coffee bean extract is more effective as an antibacterial against the bacteria Enterococcus faecalis compared to roasted Arabica coffee bean extract.

Advanced Assessment of Biomass Materials Degradation in Pneumatic Conveying Systems: Challenges and Applications

In this study, the degradation of wood pellets and dry roasted coffee beans in a pneumatic conveyor was evaluated for high-speed impacts. The change in particle size and generation of fine particles were used as an indicating parameter for the degradation. A four-bends industrial scale conveying system was used for the degradation study in lean phase pneumatic conveying. The effects of operating parameters on the degradation were investigated, including the conveying velocity of particles and particle concentration. The experimental results showed that the degradation and the fines generation increased with an increase in particle velocity. An opposite trend was observed with an increased solid concentration in the pipeline. It was found that the two types of wood pellets traveled at different particle velocities with the same operating conditions, which resulted in significant differences in the degradation. Compared to the wood pellets, roasted coffee beans were found to travel at air velocity. In conclusion, the degradation in a pneumatic conveying system is complex and challenging to evaluate because there are many influential factors, such as the type of materials, equipment, and operation conditions. Early assessments in a laboratory will be beneficial to evaluate the degradation at all controlled operative conditions.

Chemical sensory investigation in green and roasted beans Coffea arabica L. (cv. Yellow Bourbon) by various brewing methods using electronic sensors.

This study investigated the effects of four brewing methods (cold and hot brew, espresso, and cezve) on the chemical sensory properties of green and roasted coffee beans (cv. Yellow Bourbon) extract. The caffeine and chlorogenic acid contents of the coffee were analyzed using HPLC. The taste and volatile aromatic compounds of coffee were analyzed using an electronic tongue and nose, respectively, and the results were analyzed using principal component analysis. For the taste components analyzed using the electronic tongue, the degree of separation was relatively large depending on the extraction method, and the degree of separation was larger depending on roasting for the volatile compounds analyzed using the electronic nose. Our findings provide basic data for the coffee industry. PRACTICAL APPLICATION: The use of an electronic sensor will provide flavor characteristics for four different types of coffee extracted from green beans and roasted beans. In this study, it was confirmed that the extraction method had a greater effect on the taste of coffee, and in the case of the volatile aromatic compounds of coffee, there was a large difference depending on the green beans and roasted beans. Therefore, our findings will provide data based on the sensory properties of coffee.

Concentrations of polycyclic aromatic hydrocarbons in Vietnamese takeaway coffee: effects of coffee variety, roasting temperature and time

The research goal was to estimate the level of risk to human health posed by polycyclic aromatic hydrocarbons (PAHs) in Vietnamese takeaway coffee. A variety of roasted coffee beans were collected and tested for the presence of PAHs in various takeaway locations throughout Vietnam. Furthermore, the effect of roasting conditions on PAH concentrations in Vietnamese Robusta coffee was also studied and demonstrated. Gas chromatography-mass spectrometry, a modern, accurate, and fast method, was used to determine the research results. Six PAHs, namely naphthalene, anthracene, pyrene, fluorene, phenanthrene, and benz[a]anthracene, were found in the 100 collected samples, with average concentrations (μg/kg dry weight) of 943.7 ± 40.3, 195.1 ± 4.9, 36.1 ± 1.1, 33.3 ± 2.2, 28.2 ± 1.7, and 2.0 ± 0.1, respectively. It was found that the tested samples were almost free of PAH4 contamination. The research showed that the total value of PAH quantifications in Robusta coffee increased with increasing roasting temperature and decreased with increasing roasting time. In addition, the calculated value of the total hazard quotient (THQ) was less than 1, and the obtained value of the incremental lifetime carcinogenic risk (ILCR) did not exceed 1·10−5, meaning that coffee consumers in Vietnam are safe from exposure to PAHs present in the investigated coffee beans.

Pan indijska studija preseka među studentima medicine o terapijskom dejstvu kafe na tenzionu glavobolju

Introduction/Objective Tension-type headache (TTH) is the most frequent type of headache, affecting approximately 1.89 billion individuals globally. It is characterised by dull, agonising head discomfort, a sensation of tightness within the head, and tenderness of the scalp, neck, and shoulders. Coffee is a beverage made from roasted coffee beans. Coffee constituents can act as CNS stimulants, scavengers of free radicals, and have antioxidant properties. The major goal of this study is to assess the relationship between TTH and coffee consumption among medical students. This study also intends to inquire about medical students' daily coffee consumption form and amount, as well as their preference for coffee over other pharmacological treatments in headache relief. Methods Between August 31, 2023, and September 21, 2023, a pan-India cross-sectional analysis was carried out across several medical colleges in India. A self-administered questionnaire was utilised to collect data using Web-based links. Results 80% of the students experienced headaches in their everyday lives and 51.82% of students used coffee to relieve those headaches. The prevalence of TTH in coffee users was 13.06%. The prevalence of TTH in students who do not consume coffee was 12%. About 57% of students consumed about 1 tablespoon of coffee per day. In addition to that, 26.13% of students believed that coffee was equally as effective as pharmacological agents in treating headache and 11.06% of students believed that coffee was more effective than pharmacological agents. Conclusion Based on these results, we were not able to confirm a therapeutic effect of coffee on tension-type headache (TTH). On the contrary, the prevalence of TTH headaches was found to be marginally higher in coffee consumers.

Proteomic and computational analyses followed by functional validation of protective effects of trigonelline against calcium oxalate-induced renal cell deteriorations

Trigonelline is a phytoalkaloid commonly found in green and roasted coffee beans. It is also found in decaffeinated coffee. Previous report has shown that extract from trigonelline-rich plant exhibits anti-lithiatic effects in a nephrolithiatic rat model. Nevertheless, cellular mechanisms underlying the anti-lithiatic properties of trigonelline remain hazy. Herein, we used nanoLC-ESI-Qq-TOF MS/MS and MaxQuant-based quantitative proteomics to identify trigonelline-induced changes in protein expression in MDCK renal cells. From a total of 1006 and 1011 proteins identified from control and trigonelline-treated cells, respectively, levels of 62 (23 upregulated and 39 downregulated) proteins were significantly changed by trigonelline. Functional enrichment and reactome pathway analyses suggested that these 62 altered proteins were related to stress response, cell cycle and cell polarity. Functional validation by corresponding experimental assays revealed that trigonelline prevented calcium oxalate monohydrate crystal-induced renal cell deteriorations by inhibiting crystal-induced overproduction of intracellular reactive oxygen species, G0/G1 to G2/M cell cycle shift, tight junction disruption, and epithelial-mesenchymal transition. These findings provide cellular mechanisms and convincing evidence for the renoprotective effects of trigonelline, particularly in kidney stone prevention.

Differences in chemical characteristics due to different roasting of robusta coffee beans

Differences in chemical characteristics due to different roasting of robusta coffee beans

Roasted coffee beans characterization through optoelectronic color sensing

Roasted coffee beans characterization through optoelectronic color sensing

COMPETITIVE ANALYSIS OF THE WORLD COFFEE MARKET

The research is directed to systematization of information on trends in the development of the world coffee market in order to identify problems for the period from 2016 to 2021. That is why the authors not only systematize information, but also conduct competitive analysis based on statistical databases. The subject of the research is a competitive analysis of the world coffee market. The goal of the article is research and analysis of the current state of the world coffee market, identification of key players on it who are the main founders of its development processes, building a profile of their competitiveness. The following tasks are solved in the article: analysis of the current state of the world coffee market and determination of the trend of its development; identification of key players in the global coffee market and analysis of their financial indicators; assessment of the competitiveness of the largest coffee production companies in the world according to certain parameters. The methods used are: analysis and synthesis, comparison and grouping, comprehensive assessment. The results have been obtained: determining the current state and trends in the world coffee market, prices for green coffee beans, world volumes of domestic coffee production (harvest) and exports, main countries-importers and exporters of coffee beans, retail prices of roasted coffee beans among the countries of the world, volumes of sales of ready-made coffee beans, soluble products in the world, shares of the retail market trade of the world’s largest producers of grain and instant coffee products, the ratio of sales of finished coffee products in the world by geographical indication. An assessment of the competitiveness of the researched companies for the production of ready-made coffee products was carried out according to parameters, which made it possible to identify three leaders in the world market. Conclusions. The results of the competitive analysis of the global coffee market can be used in the work of consulting companies, business analysts and coffee business owners. The practical benefit of this research lies in the determination of key indicators of market functioning and the formation of a structural approach to conducting a competitive analysis of not only the world, but also the national coffee market, based on information from statistical databases.

Understanding the Effects of Self-Induced Anaerobic Fermentation on Coffee Beans Quality: Microbiological, Metabolic, and Sensory Studies.

In this study, an investigation of the microbial community structure and chemical changes in different layers of a static coffee beans fermentation tank (named self-induced anaerobic fermentation-SIAF) was conducted at different times (24, 48, and 72 h). The microbial taxonomic composition comprised a high prevalence of Enterobacteriaceae and Nectriaceae and low prevalence of lactic acid bacteria and yeast, which greatly differs from the traditional process performed in open tanks. No major variation in bacterial and fungal diversity was observed between the bottom, middle, and top layers of the fermentation tank. On the other hand, the metabolism of these microorganisms varied significantly, showing a higher consumption of pulp sugar and production of metabolites in the bottom and middle layers compared to the top part of the fermentation tank. Extended processes (48 and 72 h) allowed a higher production of key-metabolites during fermentation (e.g., 3-octanol, ethyl acetate, and amyl acetate), accumulation in roasted coffee beans (acetic acid, pyrazine, methyl, 2-propanone, 1-hydroxy), and diversification of sensory profiles of coffee beverages compared to 24 h of fermentation process. In summary, this study demonstrated that SIAF harbored radically different dominant microbial groups compared to traditional coffee processing, and diversification of fermentation time could be an important tool to provide coffee beverages with novel and desirable flavor profiles.

How to Identify Roast Defects in Coffee Beans Based on the Volatile Compound Profile

The aim of this study was to detect and identify the volatile compounds in coffee that was obtained in defect roast processes versus standard roasting and to determine the type and strength of the correlations between the roast defects and the volatile compound profile in roasted coffee beans. In order to achieve this goal, the process of coffee bean roasting was set to produce an underdeveloped coffee defect, an overdeveloped coffee defect, and defectless coffee. The "Typica" variety of Arabica coffee beans was used in this study. The study material originated from a plantation that is located at an altitude of 1400-2000 m a.s.l. in Huehuetenango Department, Guatemala. The analyses were carried out with the use of gas chromatography/mass spectrometry (GC-MS) and an electronic nose. This study revealed a correlation between the identified groups of volatile compounds and the following coffee roasting parameters: the time to the first crack, the drying time, and the mean temperatures of the coffee beans and the heating air. The electronic nose helped to identify the roast defects.

Characteristics of roasting arabica and robusta coffee beans with rotary cylinder tube roast machine with electric heat source

Arabica and Robusta coffee beans have physical differences in general. In the process of roasting coffee beans with different physical forms, it is possible that there will be differences in the roasting temperature and water content of the beans after the roasting process. Arabica and Robusta coffee beans have physical differences in general. In the process of roasting coffee beans with different physical forms, it is possible that there will be differences in the roasting temperature and water content of the beans after the roasting process. In brewing coffee, it can also be affected by the roasting process. There are several factors that need to be considered in the roasting coffea bean namely early moisture of coffea beans, temperature in the roaster and the time it takes for the coffee beans to ripen as desired. The use of heat energy to get a specific aroma and taste in coffee beans is very necessary. The objective of the research is to determine how the criteria of the roast of Arabica coffea beans and Robusta coffee beans using cylindrical roaster rotates with electrical energy as its heat source. The results obtained at the treatment temperature of 205°C using a rotating cylinder tube coffee roaster using an electric heat source takes 78 minutes to reach coffee maturity with a dark roast level of maturity. Analysis of the color of coffee beans after roasting, it was found that Arabica coffee and Robusta coffee were more dominant, showing on the color track-60 with the Agtron Color Classification System scale, where the initial moisture content of dry robusta beans is 12.50% reduced to 3.66% after roasting, while the initial moisture content of arabica beans is 12.36% reduced to 3.54%.

Optimization of QuEChERS and high performance liquid chromatography-fluorescence detection conditions to assess the impact of preparation procedures on EU priority PAHs in coffee samples and their PAHs consumption risk.

The good performance conditions for determination of EU priority PAHs in coffee samples were established to evaluate the effects of roasting degree on the PAHs in coffee beans and the brewing methods on the PAHs transfer from coffee beans to their brews. The consumption risk of the PAHs in coffee products was also assessed. The PAHs levels of the roasted coffee beans were in the order: 923.65 ng/g (dark roast) > 132.20 ng/g (medium roast) > 69.28 ng/g (light roast). Compared with general brewing with the drip bag (PAHs content, 0.30-0.62 ng/mL in coffee brews), the coffee machine brewing (set at 4 bar) induced higher PAHs release into coffee brews (PAHs content, 0.36-2.14 ng/g). The PAHs amounts of the commercial brewed and canned coffee products were 0.32-1.23 ng/g and 0.16-0.46 ng/g, respectively. The consumption risk of the PAHs in the coffee brews and products is a low level of concern.