Decolouration of Cyanophyce algae by solvent extn - using an aliphatic hydrocarbon, alcohol or ketone or an aromatic hydrocarbon and drying the residue

摘要

The decolouration of Cyanophyce algae by extn. of the pigment content comprises (a) contacting the previously dried algae with at least one substantially anhydrous solvent chosen from aliphatic-alcohols, -ketones or -hydrocarbons (satd) or satd. alicyclic hydrocarbons opt. halogenated, and opt. halogenated aromatic hydrocarbons which are permitted to be used by the food regulations in force; (b) sepn. of the algae from the solvent and (c) drying of the algae. The starting material pref. contains less than 12% water. Suitable solvents are ethanol, isopropanol, acetone, hexane, heptane and 1, 2-dichlorethane. A mixt. of acetone and alcohol (20:80 vol. %) is also suitable. The extn. is pref. conducted at 20-150 degrees C e.g. at the reflux temp. of the solvent. In step (c) the algae is pref. dried until it contains less than 150 ppm of solvent used. Pref. algae are of the genera Oscillatopica and Spirulina. The dry powers obtd. are used in the prodn. of foodstuff compsns. The process gives improved decolouration cf. the parent process.