scholarly journals Comparison of the Antioxidant Activities and Volatile Compounds of Coffee Beans Obtained Using Digestive Bio-Processing (Elephant Dung Coffee) and Commonly Known Processing Methods

Antioxidants ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 408
Author(s):  
Mesfin Haile ◽  
Hyung Min Bae ◽  
Won Hee Kang

There are different types of coffee processing methods. The wet (WP) and dry processing (DP) methods are widely practiced in different parts of coffee-growing countries. There is also a digestive bioprocessing method in which the most expensive coffee is produced. The elephant dung coffee is produced using the digestive bioprocessing method. In the present experiment, the antioxidant activity and volatile compounds of coffee that have been processed using different methods were compared. The antioxidant activity, total phenolic content (TPC), total flavonoid content (TFC), and total tannin content (TTC) of green coffee beans from all treatments were higher as compared to roasted coffee beans. Regarding the green coffee beans, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of elephant dung coffee beans was higher as compared to that of the DP and WP coffee beans. The green coffee beans had higher DPPH activity and ferric reducing antioxidant power (FRAP) value compared to the roasted coffee beans. The green beans of elephant dung coffee had a high TPC than the beans obtained by WP and DP methods. TFC in elephant dung coffee in both green and roasted condition was improved in contrast to the beans processed using dry and wet methods. The elephant dung coffee had an increased TTC in comparison to the DP and WP coffee (green beans). About 37 volatile compounds of acids, alcohols, aldehydes, amide, esters, ethers, furans, furanones, ketones, phenols, pyrazines, pyridines, Heterocyclic N, and pyrroles functional classes have been found. Some of the most abundant volatile compounds detected in all treatments of coffee were 2-furanmethanol, acetic acid, 2-methylpyrazine, 2,6-dimethylpyrazine, pyridine, and 5-methylfurfural. Few volatile compounds have been detected only in elephant dung coffee. The principal component analysis (PCAs) was performed using the percentage of relative peak areas of the volatile compound classes and individual volatile compounds. This study will provide a better understanding of the impacts of processing methods on the antioxidants and volatile compounds of coffee.

Foods ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1347
Author(s):  
Ja-Myung Yu ◽  
Mingi Chu ◽  
Hyunbeen Park ◽  
Jooyeon Park ◽  
Kwang-Geun Lee

Volatile compounds of coffee brewed under various roasting conditions and by different brewing methods were analyzed. Green coffee beans (Coffea arabica) were roasted at 235 °C for 13 min, 240 °C for 15 min, and 245 °C for 17 min. Roasted coffee beans were ground into particles of three different sizes (710, 500, and 355 μm) and brewed by an espresso coffee machine and the cold brew method. Three types of water (filtered, tap, and bottled) were used for coffee extraction. SPME-GC-MS results indicated that increasing the roasting temperature and time increased the levels of 2,2′-methylene-bis-furan, guaiacol, and 4-ethylguaiacol (p < 0.05) and decreased the levels of furfural (p < 0.05). Grind size was inversely proportional to the measured signal of volatiles by GC-MS (p < 0.05). The measured GC/MS intensities of 2-methylpyrazine, 2,5-dimethylpyrazine, and 2-methoxy-4-vinylphenol were significantly higher in coffee brewed with filtered water (p < 0.05) than tap and bottled water. 2-Methylpyrazine, 1-methylpyrrole, and 2-acetylfuran were the most abundant components in the cold brew. Overall, roasting conditions and extraction methods were determined to be significant factors for volatile compounds in coffee. This is the first study showing the analysis of volatile compounds in coffee according to various types of water and extraction methods, such as espresso and cold brew coffee.


2017 ◽  
pp. 261-268
Author(s):  
F. Kulapichitr ◽  
C. Borompichaichartkul ◽  
S. Pratontep ◽  
K. Lopetcharat ◽  
S. Boonbumrung ◽  
...  

Fermentation ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 29 ◽  
Author(s):  
Mesfin Haile ◽  
Won Kang

We examined the antioxidant activity, total polyphenol content (TPC), total flavonoid content (TFC), total tannin content (TTC) and physical characteristics of green coffee beans fermented with selected yeasts. There was no significant (p > 0.05) interaction effect between yeast-fermented coffee extracts and duration of fermentation on antioxidant activity (oxygen radical absorbance capacity [ORAC] and superoxide dismutase-like [SOD-like] activity). However, the mean of the antioxidant activity (ORAC and SOD-like activity) significantly (p < 0.05) increased in the fermented coffee extracts compared to unfermented coffee. There were significant (p < 0.05) interaction effects between yeast-fermented coffee extracts and duration of fermentation (24 h and 48 h) on the TPC, TFC, TTC and pH of the fermented solution and on the colors of the ground-roasted coffee. The TPC showed a pattern of increase in samples Ferm-1 and Ferm-3 as fermentation time increased from 24 h to 48 h. However, a decreasing TPC trend was observed in Ferm-2 as the number of fermentation hours increased from 24 to 48. The fermented coffee beans had a significantly higher flavonoid content than the unfermented coffee beans, while fermentation significantly decreased the tannin content compared to that in unfermented coffee.


2021 ◽  
Vol 306 ◽  
pp. 03024
Author(s):  
Adnan ◽  
Martina Sri Lestari

Drying and sortation are the most important steps to improve green coffee beans and cup quality. However, farmers very often neglect these steps. Therefore, a simple technique and soft approach are required to encourage farmers to implement drying and sortation technology. The study aim is to assess suitable drying and sortation technology to improve green coffee beans and cup quality to local culture in Jayawijaya Regency, Papua. The study was conducted using 2 factors; a. Combination of drying floor using a tarp and without sortation (DFWTS), b. Combination of drying tables and with sortation (DTWS). Drying tables were designed as two separate parts. The first part was the permanent tables, and the second part was removable boxes in dimension 80 x 80 cm located on top of the permanent tables. Descriptive analysis was conducted based on SNI 01-2907-2008 by the Indonesian Coffee and Cocoa Research Institute. The results show DTWS produce green coffee beans in compliance with SNI 01-2907-2008 at 4a grade, compared to DFWTS is rejected. Green coffee beans quality is likely to affect cup quality. DTWS obtain cup quality score 83.0 compare to DFWTS is 81.25. In conclusion, DTWS improve green coffee beans and cup quality.


Antioxidants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 93 ◽  
Author(s):  
Robert Acidri ◽  
Yumiko Sawai ◽  
Yuko Sugimoto ◽  
Takuo Handa ◽  
Daisuke Sasagawa ◽  
...  

The current study investigates the phytochemical composition of coffee plant organs and their corresponding antioxidant capacities compared to green and roasted coffee beans. HPLC analysis indicated that the investigated compounds were present in all organs except mangiferin, which was absent in roots, stems and seeds, and caffeine, which was absent in stems and roots. Total phytochemicals were highest in the green beans (GB) at 9.70 mg g−1 dry weight (DW), while roasting caused a 66% decline in the roasted beans (RB). This decline resulted more from 5–CQA and sucrose decomposition by 68% and 97%, respectively, while caffeine and trigonelline were not significantly thermally affected. Roasting increased the total phenolic content (TPC) by 20.8% which was associated with an increase of 68.8%, 47.5% and 13.4% in the antioxidant capacity (TEAC) determined by 2,2–diphenyl–1–picryl hydrazyl radical (DPPH), 2,2–azino bis (3–ethyl benzothiazoline–6–sulphonic acid) radical (ABTS) and Ferric ion reducing antioxidant power (FRAP) assays, respectively. Amongst the leaves, the youngest (L1) contained the highest content at 8.23 mg g−1 DW, which gradually reduced with leaf age to 5.57 mg g−1 DW in the oldest (L6). Leaves also contained the highest TPC (over 60 mg g−1 GAE) and exhibited high TEAC, the latter being highest in L1 at 328.0, 345.7 and 1097.4, and least in L6 at 304.6, 294.5 and 755.1 µmol Trolox g−1 sample for the respective assays. Phytochemical accumulation, TPC and TEAC were least in woody stem (WS) at 1.42 mg g−1 DW; 8.7 mg g−1 GAE; 21.9, 24.9 and 110.0 µmol Trolox g−1 sample; while herbaceous stem (HS) contained up to 4.37 mg g−1 DW; 27.8 mg g−1 GAE; 110.9, 124.8 and 469.7 µmol Trolox g−1 sample, respectively. Roots contained up to 1.85 mg g−1 DW, 15.8 mg−1 GAE and TEAC of 36.8, 41.5 and 156.7 µmol Trolox g−1 sample. Amongst the organs, therefore, coffee leaves possessed higher values than roasted beans on the basis of phytochemicals, TPC and TEAC. Leaves also contain carotenoids and chlorophylls pigments with potent health benefits. With appropriate processing methods, a beverage prepared from leaves (coffee leaf tea) could be a rich source of phytochemicals and antioxidants with therapeutic and pharmacological values for human health.


Author(s):  
Deepti Bajaj ◽  
Suhas Ballal

Coffee, one of the most commonly consumed beverages is a very rich source of antioxidants alongside various other health benefits. The roasted beans of coffee are the seed of berry obtained from coffea species. These roasted coffee beans are utilized to prepare coffee. India is today producer of 16 unique varieties of coffee most of which originate from southern India. The goodness of coffee and Ganoderma can do wonders to human health. This study is aimed to have an analysis of antioxidant properties of instant coffee, filter coffee, coffee with Ganoderma extracts and ginger coffee by estimating the Ascorbic Acid equivalents (AAE). The essence of the study is the presence of additions and the antioxidant activity of the coffee samples in their presence. The two infusions used in the study are extracts of Ganoderma and ginger. The study also aims to have a inter group analysis of antioxidant properties of all the samples. The study was conducted using basic colorimetric techniques.


2021 ◽  
Vol 10 (6) ◽  
pp. 3072-3082
Author(s):  
Yohanssen Pratama ◽  
I Gde Eka Dirgayussa ◽  
Paian Fernando Simarmata ◽  
Mia Hotmaria Tambunan

Coffee roasting is the process by which raw coffee beans (green beans) are roasted until they reach a certain roast level. In general, the roast level of roasted coffee beans is divided into 3 levels, namely the roast level of light, medium and dark. One way to find out the roast level of roasted coffee beans is to see the color change of the coffee beans. However, it is very difficult to know the exact color conditions of each roast level of roasted coffee beans and this can be overcome by build an automatic coffee roasting equipment. In this research, an automatic coffee roaster was done with a system that is able to control the roasting temperature and stirring of coffee beans. This tool can also monitor the change in color of the coffee beans during the roasting process. The system that has been implemented can detect color changes and classify the level of dark roast of roasted coffee beans using the Euclidean distance algorithm. The Euclidean distance give a threshold to classified the roast level. The system accuracy for predicting coffee beans color at the level of dark roast is 90% and 80% for overall.


2020 ◽  
Vol 8 (9) ◽  
pp. 1268 ◽  
Author(s):  
Asya Akbar ◽  
Angel Medina ◽  
Naresh Magan

We examined the resilience of strains of Aspergillus westerdijkiae in terms of growth and ochratoxin A (OTA) production in relation to: (a) two-way interacting climate-related abiotic factors of water activity (aw, 0.99–0.90) × temperature (25–37 °C) on green coffee and roasted coffee-based media; (b) three-way climate-related abiotic factors (temperature, 30 vs. 35 °C; water stress, 0.98–0.90 aw; CO2, 400 vs. 1000 ppm) on growth and OTA production on a 6% green coffee extract-based matrix; and (c) the effect of three-way climate-related abiotic factors on OTA production in stored green coffee beans. Four strains of A. westerdijkiae grew equally well on green or roasted coffee-based media with optimum 0.98 aw and 25–30 °C. Growth was significantly slower on roasted than green coffee-based media at 35 °C, regardless of aw level. Interestingly, on green coffee-based media OTA production was optimum at 0.98–0.95 aw and 30 °C. However, on roasted coffee-based media very little OTA was produced. Three-way climate-related abiotic factors were examined on two of these strains. These interacting factors significantly reduced growth of the A. westerdijkiae strains, especially at 35 °C × 1000 ppm CO2 and all aw levels when compared to 30 °C. At 35 °C × 1000 ppm CO2 there was some stimulation of OTA production by the two A. westerdijkiae strains, especially under water stress. In stored green coffee beans optimum OTA was produced at 0.95–0.97 aw/30 °C. In elevated CO2 and 35 °C, OTA production was stimulated at 0.95–0.90 aw.


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