Content of 4(5)-methylimidazole, caffeine and chlorogenic acid in commercial coffee brands

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F70883521%3A28610%2F15%3A43874651" target="_blank" >RIV/70883521:28610/15:43874651 - isvavai.cz</a>

Result on the web

<a href="http://www.potravinarstvo.com/journal1/index.php/potravinarstvo/article/view/422" target="_blank" >http://www.potravinarstvo.com/journal1/index.php/potravinarstvo/article/view/422</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5219/422" target="_blank" >10.5219/422</a>

Result language

angličtina

Original language name

Content of 4(5)-methylimidazole, caffeine and chlorogenic acid in commercial coffee brands

Original language description

Content of 4(5)-methylimidazole (4-MeI), caffeine and chlorogenic acid in commercial coffee brands were determined using high-performance liquid chromatography (HPLC) with UV DAD and MS detectors. Positive ion ESI mass spectra of the 4-MeI standard yielded intense signals corresponding to [M+H]+ (83.0604) and [2M+H]+ ions (165.1115). Also, adducts of 4-MeI with acetonitrile from mobile were detected - [M+ACN]+ ions (124.0849). The LOD of 2.5 ng mL-1 and LOQ of 8.4 ng.mL-1 were calculated according to the following formulas: LOD = 3.SD/S, and LOQ = 10.SD/S, where S is the slope of the calibration curve and SD is the standard deviation of the noise. The caffeine content was compared to the results of the standard addition, 1st derivative and liquid-liquid extraction spectrophotometry. 4-MeI was in tens μg g-1 in the Vietnamese coffees while in units μg.g-1 in all Czech and Brazilian coffees (<2.4 μg.g-1 and <4.9 μg.g-1, respectively). The results for caffeine were within the documented range (0.31 - 2.20%) in all coffee samples. The lower content of caffeine and chlorogenic acid was observed in Vietnamese coffees. All the methods used for determination of caffeine in the Czech and Brazilian coffees gave acceptable precision and accuracy. However, there were significant differences in the results in Vietnamese coffees. The caffeine extractability (100 oC, 3 min brewing) almost reached 100% in Czech and Brazilian coffees, while it was less than 90% in Vietnamese coffees. The Czech and Brazilian coffees tend to produce more caffeine in brews than the Vietnamese coffee because of the different composition of blends and the particle size degree.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

GM - Food industry

OECD FORD branch

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Project

—

Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2015

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Potravinárstvo

ISSN

1338-0230

e-ISSN

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Volume of the periodical

9

Issue of the periodical within the volume

1

Country of publishing house

SK - SLOVAKIA

Number of pages

8

Pages from-to

31-38

UT code for WoS article

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EID of the result in the Scopus database

2-s2.0-84983528037