DETERMINATION OF CAFFEINE CONTENTS IN VIETNAMESE AND CZECH COFFEE

Kód výsledku v IS VaVaI

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Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

DETERMINATION OF CAFFEINE CONTENTS IN VIETNAMESE AND CZECH COFFEE

Popis výsledku v původním jazyce

Caffeine contents were determined in 10 commercial coffee brands (5 Vietnamese and 5 Czech) using 3 different methods, including direct conventional UV/VIS spectrophotometry at 273.2 nm, 1st order derivative UV/VIS spectrophotometry of the sample solution using peak to peak method, and liquid-liquid extraction using chloroform (CHCl3) as an extracting solvent. Caffeine contents measured by conventional UV/VIS spectrophotometry fall out of the documented range (2.9 ? 0.05 - 15 ? 0.07 %) while those determined by derivative spectrophotometry and by CHCl3 were found to be within the documented range (0.48 ? 0.01 ? 3.47 ? 0.08 %) in all coffee samples. The 1st order derivative UV/VIS spectrophotometry and CHCl3 extraction can be used for determination of caffeine in Czech coffee brands (2.16 ? 0.04 and 2.06 ? 0.06 %, respectively). However, there were significant differences in the results between the two methods in Vietnamese coffee brands due to interference of complex matrices (1.62 ? 0

Název v anglickém jazyce

DETERMINATION OF CAFFEINE CONTENTS IN VIETNAMESE AND CZECH COFFEE

Popis výsledku anglicky

Caffeine contents were determined in 10 commercial coffee brands (5 Vietnamese and 5 Czech) using 3 different methods, including direct conventional UV/VIS spectrophotometry at 273.2 nm, 1st order derivative UV/VIS spectrophotometry of the sample solution using peak to peak method, and liquid-liquid extraction using chloroform (CHCl3) as an extracting solvent. Caffeine contents measured by conventional UV/VIS spectrophotometry fall out of the documented range (2.9 ? 0.05 - 15 ? 0.07 %) while those determined by derivative spectrophotometry and by CHCl3 were found to be within the documented range (0.48 ? 0.01 ? 3.47 ? 0.08 %) in all coffee samples. The 1st order derivative UV/VIS spectrophotometry and CHCl3 extraction can be used for determination of caffeine in Czech coffee brands (2.16 ? 0.04 and 2.06 ? 0.06 %, respectively). However, there were significant differences in the results between the two methods in Vietnamese coffee brands due to interference of complex matrices (1.62 ? 0

Druh

D - Stať ve sborníku

CEP obor

GM - Potravinářství

OECD FORD obor

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Projekt

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Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2012

Kód důvěrnosti údajů

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

Název statě ve sborníku

Bezpečnosť a kontrola potravín

ISBN

978-80-552-0769-8

ISSN

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e-ISSN

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Počet stran výsledku

6

Strana od-do

246-251

Název nakladatele

Slovenská poľnohospodárská univerzita v Nitre

Místo vydání

Nitra

Místo konání akce

Nitra

Datum konání akce

28. 3. 2012

Typ akce podle státní příslušnosti

EUR - Evropská akce

Kód UT WoS článku

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