Abstract: A method is disclosed for making a water-soluble hydrolyzate of a keratinaceous starting material which comprises first subjecting said starting material to acid treatment at a pH of 2 or below and at an elevated temperature above 80.degree. C. to effect mild hydrolysis thereof and then enzymatically degrading said acid-treated material in an aqueous bath in the presence of urea with an alkaline proteinase having an activity optimum in a range between pH 9 and pH 13, the initial pH of the enzymatic treatment being within the pH range optimum for the enzyme employed.
July 9, 1979
Date of Patent:
November 4, 1980
Firma Carl Freudenberg, R/hm GmbH
Klaus Braeumer, Zdenek Eckmayer, Alexander Berg, Rolf Monsheimer, Ernst Pfleiderer