Procedure for the extraction of phenolic compounds from olive vegetation water and preparation of extract valued in olive and grape polyphenols

摘要

Procedure for preparing a composition enriched in phenolic compounds of mlolecular mass less than or equal to 400 Da from olives vegetation waters characterized in that it consists of: (a0) an optional stage of acidification of the vegetation waters to reach a lower pH or equal to 4.3; (a) a stage of clarification of said vegetation waters by filtration, centrifugation or decantation; optionally the following three stages (a1) to (a3): (a1) the concentration of acidified and clarified marginals for storage; (a2) storage of concentrated acidified marginals; then (a3) dilution in a solvent of the concentrated acidified marginals with about 4% dry matter before putting stage (b) into practice; (b) a stage of tangential ultrafiltration of the clarified vegetation waters obtained in stage (a) in a tubular ceramic membrane with a discriminatory threshold between 100 and 200 kDa, and recovery of the permeate; (c) a nanofiltration stage of said permeate obtained in step (b) in a spiral organic membrane with discriminatory threshold between 150 and 400 Da at a pressure between 1 and 3 MPa; said membrane is such that it comprises an active layer comprising at least 50% polyamide and which allows to obtain a retention comprising at least 80% of the dry matter contained in said vegetation waters and more than 25% of hydroxytyrosol; (d) an adsorption step of the phenolic compounds contained in the permeate obtained in step (c) by passage over a polymer matrix, followed by elution of the phenolic compounds adsorbed on said matrix with an organic polar solvent and obtaining an eluted; (e) a concentration stage by vacuum distillation of the eluate obtained in step (d) leading to a concentrate called composition A; and a drying stage of said composition A.