Evaluation of ice-tea quality by DART-TOF/MS.
DART (Direct Analysis in Real Time) coupled with Time-of-Flight Mass Spectrometry (TOF/MS) has been used for analyses of ice-teas. The article focuses on quality and authenticity of ice-teas as one of the most important tea-based products on the market. Twenty-one samples of ice-teas (black and green) were analysed. Selected compounds of ice-teas were determined: theobromine, caffeine, total phenolic compounds, total soluble solids, total amino acid concentration, preservatives and saccharides were determined. Fingerprints of DART-TOF/MS spectra were used for comprehensive assessment of the ice-tea samples. The DART-TOF/MS method was used for monitoring the following compounds: citric acid, caffeine, saccharides, artificial sweeteners (saccharin, acesulphame K), and preservatives (sorbic and benzoic acid), phosphoric acid and phenolic compounds. The measured data were subjected to a principal components analysis. The HPLC and DART-TOF/MS methods were compared in terms of determination of selected compounds (caffeine, benzoic acid, sorbic acid and saccharides) in the ice-teas. The DART-TOF/MS technique seems to be a suitable method for fast screening, testing quality and authenticity of tea-based products.
Department of Food Preservation, University of Chemistry and Technology Prague, Technicka 5, 160 28, Prague 6, Czech Republic.
Aleš
A
Rajchl
Department of Food Preservation, University of Chemistry and Technology Prague, Technicka 5, 160 28, Prague 6, Czech Republic.
Jana
J
Prchalová
Department of Food Preservation, University of Chemistry and Technology Prague, Technicka 5, 160 28, Prague 6, Czech Republic.
Vojtěch
V
Kružík
Department of Food Preservation, University of Chemistry and Technology Prague, Technicka 5, 160 28, Prague 6, Czech Republic.
Rudolf
R
Ševčík
Department of Food Preservation, University of Chemistry and Technology Prague, Technicka 5, 160 28, Prague 6, Czech Republic.
Helena
H
Čížková
DART; PCA analysis; TOF; ice-tea; quality