Method for recovering peptides/amino acids and oil/fat from one or more protein-containing raw materials, products produced by the method, and use of the products

A method for recovering peptides/amino acids and oil/fat from a protein-containing raw material, wherein the method comprises:

• a. grinding the raw materials;
• b. heating the ground raw materials to temperatures in the range of 40-62° C.;
• c. optionally before and/or after the heating step, separating oil/fat from the raw materials in order to obtain a first oil product;
• d. adding water which has approximately the same or the same temperature as the raw materials, and wherein the pH of the water is adjusted by adding calcium;
• e. hydrolysing the raw materials with endogenous enzymes in order to prepare a hydrolysate;
• f. optionally during the hydrolysation step, adding a pH adjuster in order to maintain the desired pH value of the hydrolysate;
• g. removing solid particles and non-hydrolysed proteins which can be returned to the hydrolysis from the hydrolysate;
• h. periodically or continually separating off fat/oil in order to obtain a second oil product;
• i. optionally treating the hydrolysate against microorganism growth, with UV treatment;
• j. separating off the molecular weight fraction of peptides/amino acids desired by membrane filtration, of crossflow type;
• k. routing the portions of the hydrolysate that do not penetrate the membrane filter in point j back to the hydrolysis in step e;
• l. concentrating and optionally drying the permeate in order to obtain peptides/amino acids;
• and
• m. wholly or partly returning the distillate from the concentration to the permeate side of the membrane filter.