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European Food Research and Technology

, Volume 216, Issue 6, pp 539–543 | Cite as

Quantification of quality parameters for reliable evaluation of green rooibos (Aspalathus linearis)

  • Hartwig Schulz
  • Elizabeth Joubert
  • Wolfgang Schütze
Original Paper

Abstract

An LC-MS/UV-Vis method was developed for the reliable identification of the most relevant flavonoids occurring in rooibos. The amounts of the dihydrochalcones aspalathin, (2′,3,4,4′,6′-pentahydroxy-3-C-β-d-glucopyranosyldihydrochalcone), nothofagin (2′,3,4′,6′-tetrahydroxy-3-C-β-d-glucopyranosyldihydrochalcone) and other flavonoids were determined in unfermented and fermented samples, collected at different locations in South Africa. Generally, a substantial loss of both dihydrochalcones was observed after the fermentation process. An NIR spectroscopic method was developed to discriminate between unfermented and fermented rooibos and to predict the aspalathin content in unfermented rooibos. The total antioxidative activity, determined according to the ABTS·+ scavenging method, was found to correlate very good with the aspalathin content in the unfermented plant material (R2=0.812).

Keywords

Rooibos Aspalathus linearis Aspalathin HPLC quantification NIRS Antioxidant activity 

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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Hartwig Schulz
    • 1
  • Elizabeth Joubert
    • 2
  • Wolfgang Schütze
    • 1
  1. 1.Federal Centre for Breeding Research on Cultivated PlantsInstitute of Plant AnalysisQuedlinburgGermany
  2. 2.ARC Infruitec-NietvoorbijStellenboschSouth Africa

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