A continuous process for production of protein hydrolysates is proposed, in which proteins are submitted to enzymatic hydrolysis in aqueous solution, and (i) the reaction vessel is aerated from the bottom, thereby producing convection, (ii) the reaction mixture, moving as a result of convection, is led through a seaweed UF membrane present in the reaction vessel, (iii) the resultant permeate containing the hydrolysis products is withdrawn immediately after passing through the membrane and is discharged from the reactor, whereas the retentate, containing unreacted proteins and enzymes, remains in the reaction vessel, and (iv) the amount of permeate withdrawn is compensated by continuous feed of fresh starting product. The invention also relates to a device for carrying out the process.