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Complete and unequivocal 1H and 13C NMR assignments for a range of green tea polyphenols [epiafzelechin, catechin, epicatechin, gallocatechin, epigallocatechin, catechin‐3‐O‐gallate, epicatechin‐3‐O‐gallate, gallocatechin‐3‐O‐gallate, epigallocatechin‐3‐O‐gallate and epigallocatechin‐3‐O‐(3′‐O‐methyl)‐gallate] in acetone‐d6 solvent have been achieved using the 2D proton–carbon correlation experiments HMQC and HMBC and also 1D NOE difference spectroscopy.

Anthocyanin co-pigmentation is reviewed and its relevance to the colour and appearance of young red wines is outlined. Reactions between flavan-3-ols, such as are present in red wines, and the anthocyanin malvin to give yellow-orange pigments (1 -440 nm) are reported. Possible structures for these new pigments are discussed as is their probable contribution to the changing hues of red wines as they age.

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