Method for preparing soluble collagen

The present invention belongs to the collagen / gelatin field, particularly to a method for producing a bone gelatin enzymatic degradation of soluble collagen. After the addition of acid protease degradation control after bone gelatin of the present invention is a dual alkali process 90 Preparation bone gelatin obtained, the pH is adjusted 90 bis bone gelatin solution with a mineral acid, or the pH is adjusted with an inorganic base and neutral or alkaline protease bone gelatin protease degradation control; the addition of a protease bone gelatin solution was adjusted with an inorganic base or inorganic acid after the reaction at room temperature the reaction solution after the pH is 5 to 6.5; then the temperature is raised to a temperature of 65 ~ 75 ℃ heat pump mention that the enzyme in a water bath to kill 95 ~ 100 ℃ for 5 to 15 minutes, using ultrafiltration and spray drying, and final purified soluble collagen obtained dried powder product. The method of the present invention, soluble collagen obtained may be used for health care products, cosmetics, food additives and the like.