Collagen was separated from the skin of a 2 months old calf by liming, bating and alk. hydrolysis and then studied for chem. properties (hydroxyproline content, pH, dry matter, ash, relative viscosity) and stability during storage at 22 degrees C, 4 degrees C and -20 degrees C for 60 days by microbia test. All the tested hydrolyzates were stable in the study period regardless of pH changes (3.7-6.0).