Abstract: To establish a quantitative method for denatured collagen based on protease tolerance of collagen, 6 groups of denatured/non-denatured collagen samples with known content ratios were prepared，then pepsin was added in the mass ratio of 1∶5 to liquid collagen at pH value of about 2.0, the denatured collagen in the samples was digested at 30 ℃ for 24 h. The non-denatured collagen was recovered by adding sodium chloride solution with final concentration of 2 mol/L. Result showed that the recovery rates of non-denatured collagen in the 6 groups of samples were 89.96%-99.24%, indicating that this method could be used to quantitatively analyze the content ratio of denatured collagen in liquid or sponge, powder and other acid soluble collagen-based raw materials and products.

Key words: collagen, denatured collagen, pepsin tolerance, quantitative analysis