a method for the treatment of a bioflavonoid composition , comprising the contacting of the bioflavonoid composition with ethanol of at least 90 % purity at a temperature of from 10 to 80 ° c . for a period of at least 0 . 5 hour , followed by separation of the ethanol and the bioflavonoid , wherein the contacting comprises the solubilisation of the bioflavonoid in the ethanol and whereby the separation involves the recrystallisation of the bioflavonoid and whereby the contacting takes place in the presence of active carbon in an amount of 1 - 10 wt % based on the bioflavonoid .