+ Site Statistics
References:
54,258,434
Abstracts:
29,560,870
PMIDs:
28,072,757
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Translate
+ Recently Requested

Determination of the 2H/1H and 15N/14N ratios of Alkylpyrazines from coffee beans (Coffea arabica L. and Coffea canephoravar. robusta) by isotope ratio mass spectrometry



Determination of the 2H/1H and 15N/14N ratios of Alkylpyrazines from coffee beans (Coffea arabica L. and Coffea canephoravar. robusta) by isotope ratio mass spectrometry



Journal of Agricultural and Food Chemistry 53(20): 7925-7930



The delta15N(AIR) and delta2H(VSMOW) data for several alkylpyrazines formed during the roasting process of coffee are reported. Samples of commercially available roasted (n = 9) as well as self-roasted (n = 8) coffee beans (Coffea arabica L. and Coffea canephora var. robusta) of different origins were investigated. By use of extracts prepared by simultaneous distillation extraction (SDE) and subsequently fractionated by liquid chromatography on silica gel, on-line capillary gas chromatography-isotope ratio mass spectrometry was employed in the combustion (C) and pyrolysis (P) modes (HRGC-C/P-IRMS) to determine the delta15N(AIR) and delta2H(VSMOW) values, respectively. In addition to the constituents of coffee beans, data for commercial synthetic alkylpyrazines and substances declared to be "natural" were determined. The delta15N(AIR) data for coffee alkylpyrazines under study-2-ethyl-5-methylpyrazine (1) and 2-ethyl-6-methylpyrazine (2) (measured as sum 1/2), 2-ethyl-3-methylpyrazine (3), 2-methylpyrazine (4), 2,5-dimethylpyrazine (5) and 2,6-dimethylpyrazine (6) (measured as sum 5/6), and 2,3-dimethylpyrazine (7), as well as 2,3,5-trimethylpyrazine (8)-varied in the range from +8.3 to -10.2 per thousand, thus revealing their biogeneration from amino acids (delta15N(AIR) ranging from +8 per thousand to -10 per thousand). The delta2H(VSMOW) values were determined in the range from -5 per thousand to -127 per thousand. Owing to the analytical differentiation observed between coffee alkylpyrazines and synthetic/"natural" samples of 3, 4, and 7, authenticity assessment of coffee-flavored products seems to be promising, provided that extended data will be available in the future. In the literature, there were no IRMS data available for the alkylpyrazines (1-8) under study.

(PDF emailed within 0-6 h: $19.90)

Accession: 048753880

Download citation: RISBibTeXText

PMID: 16190651

DOI: 10.1021/jf0509613


Related references

Determination of the 2H/1H and 15N/14N Ratios of Alkylpyrazines from Coffee Beans (Coffea arabica L. and Coffea canephora var. robusta) by Isotope Ratio Mass Spectrometry. Journal of Agricultural and Food Chemistry 53(20): 25-30, 2005

Stubby roots of coffee d seedlings caused by rotylenchulus reniformis di chloro propene di chloro propane pestic coffea arabica d coffea robusta d coffea excelsa d. Philippine Agriculturist 51(8): 36-43, 1968

Discrimination between Coffea arabica and Coffea canephora variant robusta beans using infrared spectroscopy. Food Chemistry. 54(3): 321-326, 1995

Cytology of polyploids in coffea robusta x coffea arabica hybrids of coffee. Journal of Coffee Research 14(3): 75-84, 1984

Quantification of Coffea arabica and Coffea canephora var. robusta in roasted and ground coffee blends. Talanta 106: 169-173, 2013

The transpiration of three Coffea-species, measured in different ways Coffea arabica, Coffea liberica, Coffea bengalensis, coffee.1. Flora morphologie geobotanik oekophysiologie72(2): 180-192, 1982

Homostachydrine (pipecolic acid betaine) as authentication marker of roasted blends of Coffea arabica and Coffea canephora (Robusta) beans. Food Chemistry 205: 52-57, 2016

Evaluation of callus growth in coffee species, Coffea canephora (variety Robusta) and Coffea arabica (variety 9722), in three culture media. Cultivos Tropicales 15(2): 80-83, 1994

Differential regulation of caffeine metabolism in Coffea arabica (Arabica) and Coffea canephora (Robusta). Planta 241(1): 179-191, 2016

Differential regulation of grain sucrose accumulation and metabolism in Coffea arabica (Arabica) and Coffea canephora (Robusta) revealed through gene expression and enzyme activity analysis. New Phytologist 178(4): 781-797, 2008

Screening for 16-O-methylcafestol in roasted coffee by high-performance thin-layer chromatography-fluorescence detection - Determination of Coffea canephora admixtures to Coffea arabica. Journal of Chromatography. a 1525: 173-180, 2017

Attractives to africanized hone bees and pollination in coffee flowers Coffea arabica L Atrativo para as abelhas Apis mellifera e polinizacao em cafe Coffea arabica L. Brazilian Journal of Veterinary Research and Animal Science, 401-6: 272-278, 2003

3,4-Dimethoxycinnamic acid levels as a tool for differentiation of Coffea canephora var. robusta and Coffea arabica. Food Chemistry 61(4): 511-514, 1998

Research on the presence of coffea arabica in mixtures with coffea robusta. Rivista della Societa Italiana di Scienza dell'Alimentazione 20(6): 427-429, 1991

`Top working` of Coffea canephora `Robusta` cv. S.274 with Coffea arabica cv. `Cauvery`. Journal of Coffee Research 23(2): 121-125, 1993