| abstract |
The invention provides a method for the solvent-extraction of β-carotene from an aqueous algal biomass suspension, whereby a vegetable oil which is immiscible with water is mixed with an aqueous biomass suspension, the biomass containing the β-carotene, to form a mixture of the organic phase and the aqueous suspension, whereby the β-carotene is caused to dissolve in the organic phase. This is followed by separation of the organic phase from the aqueous phase by passing the organic phase containing the dissolved β-carotene through a semi-permeable membrane to effect microfiltration or ultrafiltration of the organic phase. The membrane is of a material which is hydrophobic and the organic phase is passed through the membrane with a pressure drop across the membrane which is lower than that which causes the aqueous phase to pass through the membrane. |