Journal of Chemical Technology and Biotechnology, Vol.60, No.4, 397-403, 1994
Preparation of Spherically Agglomerated Crystals of the 3,5-Diglucoside of Cyanidin (Cyanin)
Suitable proportions of the solvent mixture benzene:methanol:aqueous hydrochloric acid to yield the spherically agglomerated crystals of cyanin have been found. The physicochemical properties and dissolution rate of the agglomerates, in comparison with the crystals obtained by a conventional method, have been analysed. No change in the crystalline form of the basic crystals was found in acid conditions, after agglomeration. The dissolution rate of spherical agglomerates did not decrease as much as predicted from their low specific surface areas because of their improved wettability. The crystallization speed would not only avoid colour loss during the isolation and purification of anthocyanins from their natural sources, but also would increase production, save time and cost. On the other hand, a decrease in the specific surface areas will reduce powder hygroscopicity with subsequent technological and stability advantages.
Keywords:CRYSTALLIZATION