title: Application of High Resolution-Continuum Source Flame Atomic Absorption Spectrometry (HR-CS FAAS): determination of trace elements in tea and tisanes.
abstract: A new application of HR-CS FAAS (High Resolution-Continuum Source Flame Atomic Absorption Spectrometry) has been developed for the determination of several trace elements (Ca, Co, Cu, Fe, Mn, Ni, Na and Zn) in infusions made from tea, rooibos and tea with seaweed samples. The proposed methods are fast, inexpensive and show good performances: the mean analytical recovery was approximately 100%. The mean limit of detection was 29.4 μg/l, and the mean limit of quantification was 98.0 μg/l (both limits refer to the brewed samples). Due to the matrix effect observed, the standard addition method had to be applied. Preliminary classification (based on metal contents) using chemometric techniques such as PCA (Principal Component Analysis) and CA (Cluster Analysis), was successful for infusions made from rooibos and tea with seaweed, but inconclusive for black and green teas.
authors.affiliation: University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, School of Sciences, 15782 Lugo, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Paz-Rodríguez
authors.affiliation: University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, School of Sciences, 15782 Lugo, Spain.
authors.forename: María Raquel
authors.initials: MR
authors.lastname: Domínguez-González
authors.affiliation: University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, School of Sciences, 15782 Lugo, Spain. Electronic address: m.aboal@usc.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Aboal-Somoza
authors.affiliation: University of Santiago de Compostela, Department of Analytical Chemistry, Nutrition and Bromatology, School of Chemistry, 1782 Santiago de Compostela (La Coruña), Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Bermejo-Barrera
mesh_terms: D036903:Aspalathus / Q000737:chemistry; D016000:Cluster Analysis; D005524:Food Technology / Q000295:instrumentation / Q000379:methods*; D006851:Hydrochloric Acid / Q000737:chemistry; D025341:Principal Component Analysis; D012624:Seaweed / Q000737:chemistry; D013054:Spectrophotometry, Atomic; D013662:Tea / Q000737:chemistry*; D014131:Trace Elements / Q000032:analysis*
chemical_list: D013662:Tea; D014131:Trace Elements; D006851:Hydrochloric Acid
keywords: Brewed sample; Flame atomization; HR-CS AAS; Tea; Tea with seaweed; Trace element