The aim of the invention is to provide a method for producing protein hydrolysates that have defined molecular weight limits without carrying out enzymatic or pH-adjusting process steps. For this purpose, the method for producing protein hydrolysates from proteinaceous plant and animal materials is characterized by splitting the materials up in an aqueous medium under a targeted pressure build-up in a reaction chamber, the temperature and reaction being controlled by a characteristic curve of the system, and separating the suspension after splitting into a sediment containing the insoluble components of the starting material, and an aqueous supernatant in which the cleavage products of the materials are dissolved.