title: Multivariate data reduction and discrimination of black and green teas due to the physical fractionation pattern of selected metals determined in their infusions.
abstract: An analytical scheme for the physical fractionation of Al, Ba, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Sr and Zn in black and green teas infusions was proposed. It was based on the ultrafiltration/centrifugation through five membranes having molecular weight cut-offs of 100, 50, 30, 10 and 5kDa. The concentrations of the studied metals in the highest and the lowest molecular weight fractions were found to classify and discriminate the analyzed teas infusions much better than the total metals concentrations. The differences in the physical fractionation patterns of these metals assessed for both tea varieties was profound and let to simply classify the infusions of different black and green teas by principal component analysis and linear discriminant analysis.
authors: Wroclaw University of Technology, Faculty of Chemistry, Division of Analytic Chemistry and Chemical Metallurgy, Wybrzeze Wyspianskiego 27, Wroclaw, 50-370 Poland. Electronic address: pawel.pohl@pwr.edu.pl.
authors: Pawel
authors: P
authors: Pohl
authors: Wroclaw University of Technology, Faculty of Chemistry, Division of Analytic Chemistry and Chemical Metallurgy, Wybrzeze Wyspianskiego 27, Wroclaw, 50-370 Poland.
authors: Anna
authors: A
authors: Szymczycha-Madeja
authors: Wroclaw University of Technology, Faculty of Chemistry, Division of Analytic Chemistry and Chemical Metallurgy, Wybrzeze Wyspianskiego 27, Wroclaw, 50-370 Poland.
authors: Ewelina
authors: E
authors: Stelmach
authors: Wroclaw University of Technology, Faculty of Chemistry, Division of Analytic Chemistry and Chemical Metallurgy, Wybrzeze Wyspianskiego 27, Wroclaw, 50-370 Poland.
authors: Maja
authors: M
authors: Welna
mesh_terms: D016002:Discriminant Analysis; D008670:Metals / Q000032:analysis* / Q000737:chemistry; D025341:Principal Component Analysis; D013054:Spectrophotometry, Atomic; D013662:Tea / Q000737:chemistry*
chemical_list: D008670:Metals; D013662:Tea
keywords: Black tea; Green tea; Infusions; Metals; Physical fractionation; Ultrafiltration