A process is provided for obtaining proteins from native substance mixtures, wherein a native substance mixture is first finely disintegrated and optionally processed to form a flowable slurry (I) by adding liquid. The process includes the following steps: (i) setting the pH value of the slurry (I) in an alkaline range (ii) adding at least one water-soluble organic solvent after setting the pH value of the slurry according to step (i) and (iii) separating a protein phase (VI) from the slurry after step (ii)