Process for extracting minor fatty compounds from a substance of biological origin

A process for extracting minor fatty compounds selected from the group consisting of steroids, fatty alcohols, fat soluble vitamins, pigments, hydrocarbons and flavouring compounds from a substance of biological origin containing fatty substances, comprising the steps of:

• selecting a substance of biological origin containing said minor fatty compounds and fatty substances;
• selecting a cyclodextrin in pulverulent form capable of forming inclusion complexes with said minor fatty compounds, from the group consisting of substituted and unsubstituted alpha, beta and gamma cyclodextrin;
• providing an amount of said cyclodextrin of from 0.5 to 15% relative to the dry matter of the substance of biological origin to be treated;
• contacting the amount of cyclodextrin with the substance of biological origin in an aqueous reaction medium at a temperature about 10.degree. C. to 25.degree. C. and maintaining the water content of the reaction medium so as to obtain a saturation level of cyclodextrin in water equal to or greater than 1.67 at the reaction temperature and so that the cyclodextrin is in a partially undissolved form;
• mixing during 10 to 120 minutes the cyclodextrin with the substance of biological origin so as to obtain a pasty mixture and to allow the formation of the said inclusion complexes;
• separating, the said inclusion complexes formed during the contacting step from the said substance of biological origin by centrifugation, by decantation, or by heating the mixture obtained to a temperature at which not more than 1% of the fatty substances present in the substance of biological origin are in a solid or crystalline state;
• and
• recovering the substance of biological origin with a reduced content of minor fatty compounds.