▎ 摘　　要

NOVELTY - Method for producing collagen tripeptide by cow skin involves obtaining fresh cow skin, washing the skin, removing hair, cutting into small blocks, adding the small blocks into sodium chloride solution, soaking blocks, drying, adding dried blocks to sodium hydroxide solution, washing with water, mixing the pre-treated cow leather and water, heating the mixture, filtering the residue, adding the modified cowhide to the excitation liquid, naturally cooling, washing by water, drying the mixture, crushing, uniformly mixing the excited cow leather powder and water, cooling, increasing the temperature to 50°C, adjusting pH of the formic acid to 6, adding protease and accelerant to the mixture, performing enzymolysis, adding alkaline protease, performing enzymolysis, inactivating the collagen tripeptide solution, centrifuging the solution, collecting supernatant, decoloring and deodorizing by K15 activated carbon column, and spray-drying collagen tripeptide. USE - The method is useful for producing collagen tripeptide. ADVANTAGE - The method provides high collagen tripeptide yield, high hydroxyproline content, total nitrogen content, less ash content, fine finished product and good water solubility and is suitable for mass production. DETAILED DESCRIPTION - Method for producing collagen tripeptide by cow skin involves obtaining fresh cow skin, washing the skin, removing hair, cutting into small blocks of ≯ 4×4 mm, adding the small blocks into sodium chloride solution with mass fraction of 3-7%, soaking blocks at normal temperature for 1 hour, drying water, adding dried blocks to 0.1 mol/l sodium hydroxide solution, uniformly stirring the solution at 3-5°C, soaking for 2-4 days, washing with water for 3-5 times to obtain pre-treated cow leather, mixing the pre-treated cow leather and water in a mass ratio of 1:5 under condition of 0.8-1 MPa, heating the mixture at 100°C for 20-30 minutes, cooling to 50-60°C, filtering the residue by double-layer gauze to obtain modified cow leather, adding the modified cowhide to the excitation liquid, soaking at 35-45°C for 30-50 minutes, increasing the temperature to 80-85°C, maintaining for 3-5 minutes, naturally cooling to room temperature, washing by water, drying the mixture, crushing and sieving by 80-100 meshes sieve to obtain excited cow leather powder, uniformly mixing the excited cow leather powder and water in a weight ratio of 1:5, cooling to -10°C for 5 minutes, increasing the temperature to 50°C, adjusting pH of the formic acid to 6, adding protease and accelerant to the mixture, performing enzymolysis at 50°C for 3-5 hours, adding alkaline protease, performing enzymolysis at 60°C for 2-3 hours to obtain collagen tripeptide liquid, inactivating the collagen tripeptide solution, centrifuging the solution, collecting supernatant, decoloring and deodorizing by K15 activated carbon column, and spray-drying collagen tripeptide.