Naslov
VOLTAMMETRIC DETERMINATION OF CHLOROGENIC ACIDS CONTENT IN COFFEE

Autori
Tomac, Ivana ; Jurić, Marijana ; Lacković, Mario ; Jakobek, Lidija

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts 17th Ružička Days / Tomas, Srećko ; Ačkar, Đurđica - Osijek : Zagreb : Prehrambeno tehnološki fakultet Sveučilišta Josipa Jurja Strossmayera u Osijeku ; Hrvatsko društvo kemijskih inženjera i tehnologa (HDKI), 2018, 70-70

ISBN
978-953-7005-57-3

Skup
17. Ružičkini dani "Danas znanost - sutra industrija"

Mjesto i datum
Vukovar, Hrvatska, 19.09.2018. - 21.09.2018

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
electrochemical methods, ground coffee, instant coffee, chlorogenic acids

Sažetak
The voltammetric determination of chlorogenic acids content in eight different brands of coffee (four different brands of ground coffee and four different brands of instant coffee) was investigated. The main chlorogenic acid isomer in coffee samples is 5-O-caffeoylquinic acid (5-CQA) and because of that is chosen as a standard. Before the determination of chlorogenic acids content, the electrochemical properties of the 5-CQA were analysed by the square-wave voltammetry (SWV) and differential pulse voltammetry (DPV). The voltammetric measurements of the 5-CQA have provided information about oxidation mechanism of dominant chlorogenic acid isomer in coffee samples that occur on the surface of the glassy carbon electrode (GCE). The quantification of the total chlorogenic acids content in different brands of coffee was performed by the SWV and DPV using calibration curves. The voltammetric characterization of 5-CQA and coffee samples in 0.1 M phosphate buffer pH 7 were performed. All coffee samples were showed net peak signals at almost the same potential as 5-CQA (Ep = 0.223 V for SWV and Ep = 0.187 V for DPV). Additionally, spectrophotometric method was performed in order to compare the total content of chlorogenic acids in coffee samples with performed voltammetric methods. The total content of chlorogenic acids obtained by the SWV, DPV and Folin-Ciocalteu methods in coffee samples was expressed as mg 5-CQA per 100g of coffee.

Izvorni jezik
Hrvatski

Znanstvena područja
Kemija, Prehrambena tehnologija

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