In black currants the contents of quercetin- and especially of myricetin glycosides increased during ripeness very considerably. The myricetin level in ripe fruits of cultivated blueberries and the quercetin level in ripe berries of privet was higher than in unripe. However, the concentrations of kaempferol and quercetin glycosides were in most of the fruits (e.g. red and white currants, sour cherries, plums, cultivated blueberries, elderberries) smaller than in unripe fruits. Anthocyanin formation is therefore not combined with an accumulation of flavonols (perhaps with the exception of myricetin).