Planta Med 2014; 80(12): 1023-1028
DOI: 10.1055/s-0034-1382904
Analytical Studies
Original Papers
Georg Thieme Verlag KG Stuttgart · New York

Herbal Tea Identification Using Mid-Infrared Spectroscopy

Meta Kokalj
Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
,
Karmen Štih
Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
,
Samo Kreft
Faculty of Pharmacy, University of Ljubljana, Ljubljana, Slovenia
› Author Affiliations
Further Information

Publication History

received 21 November 2013
revised 25 April 2014

accepted 30 June 2014

Publication Date:
06 August 2014 (online)

Abstract

Herbal teas and other herbal preparations are becoming more and more popular, and it is essential to ensure their quality. Quality control methods that are simple, fast, and of low cost are needed by the producers and by inspections. Infrared spectroscopy coupled with multivariate mathematical methods has been shown to be useful for the identification and characterization of plant samples. In this work, we developed a method for the identification of herbal drugs in different herbal teas. 100 one-component herbal teas were first used to build an identification algorithm, which showed 100 % correct classification. In the next validation step, 13 samples from 7 herbal mixtures were analyzed, confirming high accurate results for classification. The influence of using different number of components in the principal component analysis is also explored. Infrared spectroscopy coupled with analysis of variance, principal component analysis, and discriminant analysis was shown to be highly applicable for quality control procedures.

Supporting Information

 
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