Evaluation of the physiochemical and metabolite of different region coffee beans by using UHPLC-QE-MS untargeted-metabonomics approaches

This paper reports on the chemical compounds in arabica coffee beans with a high Specialty Coffee Association (SCA) cupping score, especially those in specialty coffee beans. We investigated the relationship between the chemical compounds and cupping scores by considering 16 types of Coffea arabica (arabica coffee) beans from Guatemala (SCA cupping score of 76.5–89.0 points). Non-targeted gas chromatography-mass spectrometry-based chemometric profiling indicated that specialty beans with a high cupping score contained considerable amounts of methyl-esterified compounds (MECs), including 3-methylbutanoic acid methyl ester (3-MBM), and other fatty acid methyl esters. The effect of MECs on flavor quality was verified by spiking the coffee brew with 3-MBM, which was the top-ranked component, as obtained through a regression model associated with cupping scores. Notably, 3-MBM was responsible for the fresh-fruity aroma and cleanness of the coffee brew. Although cleanness is a significant factor for specialty beans, the identification of compounds that contribute to cleanness has not been reported in previous research. The chemometric profiling approach coupled with spiking test validation will improve the identification and characterization of 3-MBM commonly found in arabica specialty beans. Therefore, 3-MBM, either alone or together with MECs, can be used as a marker in coffee production.

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Heavy-Metal Contents and the Impact of Roasting on Polyphenols, Caffeine, and Acrylamide in Specialty Coffee Beans

Foods ◽

10.3390/foods10061310 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1310

Author(s):

Matúš Várady ◽

Sylwester Ślusarczyk ◽

Jana Boržíkova ◽

Katarína Hanková ◽

Michaela Vieriková ◽

...

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Dry Matter ◽

Green Beans ◽

Caffeoylquinic Acids ◽

Coffee Beans ◽

Metal Contents ◽

Specialty Coffee ◽

Quantitative Analyses ◽

The Impact

The aim of this study was to determine the effect of roasting on the contents of polyphenols (PPH), acrylamide (AA), and caffeine (CAF) and to analyze heavy metals in specialty coffee beans from Colombia (COL) and Nicaragua (NIC). Samples of NIC were naturally processed and COL was fermented anaerobically. Green beans from COL (COL-GR) and NIC (NIC-GR) were roasted at two levels, light roasting (COL-LIGHT and NIC-LIGHT) and darker roasting (COL-DARK and NIC-DARK), at final temperatures of 210 °C (10 min) and 215 °C (12 min), respectively. Quantitative analyses of PPH identified caffeoylquinic acids (CQA), feruloylquinic acids, and dicaffeoylquinic acids. Isomer 5-CQA was present at the highest levels and reached 60.8 and 57.7% in COL-GR and NIC-GR, 23.4 and 29.3% in COL-LIGHT and NIC-LIGHT, and 18 and 24.2% in COL-DARK and NIC-DARK, respectively, of the total PPH. The total PPH contents were highest in COL-GR (59.76 mg/g dry matter, DM). Roasting affected the contents of PPH, CAF, and AA (p < 0.001, p < 0.011 and p < 0.001, respectively). Nickel and cadmium contents were significantly higher in the COL-GR than in the NIC-GR beans. Darker roasting decreased AA content, but light roasting maintained similar amounts of CAF and total PPH.

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Characterization of Penicillium crustosum l-asparaginase and its acrylamide alleviation efficiency in roasted coffee beans at non-cytotoxic levels

Archives of Microbiology ◽

10.1007/s00203-021-02198-6 ◽

2021 ◽

Author(s):

Neveen M. Khalil ◽

Susana Rodríguez-Couto ◽

Mohamed N. Abd El-Ghany

Keyword(s):

Roasted Coffee ◽

Coffee Beans ◽

Penicillium Crustosum ◽

Roasted Coffee Beans

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Analysis of Volatile Compounds in Coffee Prepared by Various Brewing and Roasting Methods

Foods ◽

10.3390/foods10061347 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1347

Author(s):

Ja-Myung Yu ◽

Mingi Chu ◽

Hyunbeen Park ◽

Jooyeon Park ◽

Kwang-Geun Lee

Keyword(s):

Volatile Compounds ◽

Extraction Methods ◽

Measured Signal ◽

Roasted Coffee ◽

Green Coffee Beans ◽

Coffee Beans ◽

Espresso Coffee ◽

Roasting Temperature ◽

Roasted Coffee Beans ◽

Significant Factors

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.

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