process for extracting xanthophyll crystals from a plant extract

摘要

The process for extracting xanthophyll crystals from a xanthophyll diester containing plant extract (oleoresin) comprises: a) admixing the oleoresin with propylene glycol with heating to a temperature to a temperature of 50 to 60oC to form a homogeneous liquid; b) admixing an aqueous alkali solution of sodium or potassium hydroxide with the liquid from step a) to form a saponification reaction mixture that consists essentially of 35 to 50 wt% oleoresin, 30 to 45 wt% propylene glycol, 5 to 10 wt% alkali as sodium or potassium hydroxide and 7 to 15 wt% water as initially admixed components wherein the total weight of the oleoresin and propylene glycol constitutes at least 75 wt% of the reaction mixture; c) maintaining the mixture of step b) at a temperature of 65 to 80oC for a time period to saponify the xanthophyll diester and form a saponified reaction mixture containing xanthophyll crystals; d) admixing 3 to 19 volumes of water at a temperature of 60 to 800C per volume of the mixture of step c) to form a diluted reaction mixture containing xanthophyll crystals; e) gently admixing the diluted reaction mixture until homogeneous; f) collecting the xanthophyll crystals from the diluted mixture of step e) and g) washing and then drying the collected xanthophyll crystals.