Journal of Chemical Ecology

, Volume 19, Issue 4, pp 613–621 | Cite as

Vanillin-HCl method for condensed tannins: Effect of organic solvents used for extraction of tannins

  • H. P. S. Makkar
  • K. Becker
Article

Abstract

Tannins are generally extracted using aqueous organic solvents, mainly methanol and acetone. The presence of various concentrations of methanol in the sample containing catechin or tannins did not alter the kinetics of their reaction, but the absorbance depended on the amount of methanol in the sample; the higher the methanol, the higher was the absorbance. Acetone reacted with acidified vanillin to produce a chromogen with λmax at 548 nm, which produce a substantial error in the determination of condensed tannins. In the presence of acetone, the time courses of the reaction for catechin and tannins were different, which depended on the acetone concentration and the reaction temperature. Reaction conditions for catechin and tannins that enable their measurement in the presence of acetone are presented.

Key Words

Condensed tannins catechin vanillin-HCl method organic solvents methanol acetone 

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Copyright information

© Plenum Publishing Corporation 1993

Authors and Affiliations

  • H. P. S. Makkar
    • 1
  • K. Becker
    • 1
  1. 1.Institute for Animal Production in the Tropics and Subtropics (480)University of HohenheimStuttgart 70Germany

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