The invention relates to a method for producing a dehydrated food with a high content of hydrolysed proteins from fish stickwater. To this end, the insoluble solids and the traces of fat are separated from the stickwater, the stickwater is then subjected to a process of demineralisation by means of electrodialysis, and the temperature and pH thereof are subsequently adjusted so as to proceed with the enzymatic hydrolysis, which allows the protein to be fractionated, said protein then being concentrated and dried by atomisation in a dehydrator such as a spray dryer, and lastly the dry product is suitably packaged
