T-A/T-T under oxidative conditions TA/TT mechanisms - non-oxidative Creativity and innovation leads to discovery You are here Anthocyanins and Procyanidins Tannins and the Structure of the main procyanidin Oak and Oxygen
Proposed role of co-pigmentation
1. Anthocyanins contain aromatic rings (hydrophobic) which are highly hydroxylated (hydrophillic).

2. The sugar esterified to the 3 position of the C ring helps to maintain solubility

3. Must conditions favor water soluble compounds; wine conditions are more favorable for hydrophobic compounds.

4. Other compounds present with similar properties will tend to aggregate and stack to protect the hydrophobic centers.

5. Conditions during later fermentation (increasing alcohol and temperature) favor disruption of these aggregated or stacked complexes.

6. Presence of crosslinkers and close proximity of anthocyanins and phenolics polymers (co-pigmentation) favors the crosslinking reaction.

7. Toasted oak provides compounds able to both co-pigment (stack) and crosslink, favoring the formation of stabilized pigments.


A pictorial of tannins and anthocyanins solubilizing is on the left; stabilizing themselves through stacking and aggregation is in the middle. On the right, (depending on conditions), tannins and anthocyanins will either bond directly or crosslink if acetaldehyde, furfural, HMF or 5-methyl furfural are present.
  It is the relative proximity and orientation of the molecules that may be the most important role of co-pigmentation. This closeness and arrangement of the molecules may aid in the crosslinking reaction, much in the manner that enzymes work when catalyzing reactions between molecules.