Studies on the acetaldehyde-induced condensation of (-)-epicatechin and malvidin 3-O-glucoside in a model solution system

J Agric Food Chem. 1999 May;47(5):2096-102. doi: 10.1021/jf9806309.


The reaction between (-)-epicatechin, malvidin 3-O-glucoside, and acetaldehyde was studied in a model solution system. Ethyl-linked flavanol oligomers and anthocyanin-flavanol derivatives were observed, showing that the two polyphenols competed in the condensation process. Among the anthocyanin-ethyl-flavanol adducts, dimeric compounds in which the flavanol was linked to the anthocyanin with CH(3)-CH bridges were observed. In addition, trimeric and tetrameric products containing one anthocyanin and one, two, or three flavanols units were detected. A tetrameric product containing two anthocyanin and two flavanol units was also found as a doubly charged ion. No compound containing more than two malvidin 3-O-glucosides was detected, suggesting that only one anthocyanin A ring summit can be included in the polymerization process, which thus stops when both ends are occupied by an anthocyanin moiety. Thioacidolysis of the two isolated anthocyanin-ethyl-flavanol dimeric derivatives showed that anthocyanin-ethyl linkage was not sensitive to such reactants, whereas the flavanol-ethyl one was. In addition, flavanol-ethyl linkages involved in anthocyanin-ethyl-flavanol adducts were found to be less sensitive to those involved in flavan-ethyl dimers.

MeSH terms

  • Acetaldehyde*
  • Anthocyanins / chemistry*
  • Catechin / chemistry*
  • Chromatography, High Pressure Liquid
  • Flavonoids / chemistry
  • Models, Chemical


  • Anthocyanins
  • Flavonoids
  • Catechin
  • Acetaldehyde