Patent ID: 7439377

Claim:
A method for preparing a concentrate which is enriched with a desired isomer (a) starting from a mixture (A) selected from the group consisting of a mixture comprising at least two isomers of a C 16 or higher conjugated unsaturated fatty acid and a mixture comprising at least two cis-isomers of a C 16 or higher unsaturated fatty acid having a double bond involved in the cis-configuration thereof, wherein the method comprises a step of mixing the mixture (A) with at least one C 4 -C 14 saturated fatty acid (B) to thus form a mixed solution containing the desired isomer (a) dissolved therein; a crystallization and precipitation step in which crystals enriched with the isomer (a) are separated from the mixed solution or crystals having the reduced concentration of the isomer (a) are separated from the mixed solution; and a solid-liquid separation step for recovering crystals enriched with the isomer (a) or for removing the crystals having the reduced concentration of the isomer (a) to thus recover a solution enriched with the isomer (a).