The present invention is directed a process for the manufacture of a
powder comprising vegetation water rich in water-soluble polyphenols,
especially rich in hydroxytyrosol, as well as to the powders themselves
and dietary supplements, especially in form of tablets, food, feed and
cosmetic preparations containing such powders. The process comprises the
following steps: A) providing vegetation water (concentrate) containing
water-soluble polyphenols; B) (optionally) modifying the water content of
the vegetation water (concentrate); C) optionally centrifuging the
vegetation water (concentrate) and separating the water-soluble part; D)
spray-drying or granulating the (water-soluble part of the) vegetation
water (concentrate), preferably in presence of an adjuvant; E) optionally
washing the thus obtained powder comprising vegetation water rich in
water-soluble polyphenols with an organic solvent.