Protein isolate

Abstract

A process for producing a protein isolate from an oilseed meal, and the isolate thus obtained, said isolate comprising proteins and an amount of 4 wt % or less of phytic acid, said amount of phytic acid being by weight of proteins in said isolate. The process may comprise the following steps: a) providing an oilseed meal; b) mixing the oilseed meal with a first aqueous solvent to form a slurry at a pH ranging from 6 to 7.8, said slurry having a solid phase; c) separating said solid phase from said slurry, d) mixing said separated solid phase with a second aqueous solvent at a pH ranging from 1 to 3.5, preferably from 2 to 3, to form a mixture said mixture having a liquid phase; e) separating said liquid phase from said mixture formed in step d); f) f1) mixing the separated liquid phase to a phytase at a temperature and a pH suitable for phytase activity to obtain a mixture having a liquid phase and a solid phase; and/or f2) mixing the separated liquid to a salt, to obtain a resulting liquid composition having a molar concentration of said salt ranging from 0.05 M to 0.5 M, at a temperature ranging from 40° C. to 70° C., to obtain a mixture having a liquid phase and a solid phase; g) precipitating a solid phase from the liquid of step f) for example by a cooling down step of the mixture to a temperature of 30° C. or less; h) separating said solid precipitate from the liquid of step g) said liquid comprising a water-rich liquid phase and an oil-rich liquid phase; i) separating said water-rich liquid phase from said oil-rich liquid phase, j) subjecting said water-rich liquid phase obtained in step i) to one or several membrane filtration(s) to obtain a protein isolate; and k) optionally, drying said protein isolate to obtain a dry protein isolate.